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  • 1. Adrian, Rita
    et al.
    O`Reilly, Catherine M.
    Zagarese, Horacio
    Baines, Stephen B.
    Hessen, Dag O.
    Keller, Wendel
    Livingstone, David M.
    Sommaruga, Ruben
    Straile, Dietmar
    Van Donk, Ellen
    Weyhenmeyer, Gesa A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Winder, Monika
    Lakes as sentinels of climate change2009In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 54, no 6(2), p. 2283-2297Article in journal (Refereed)
    Abstract [en]

    While there is a general sense that lakes can act as sentinels of climate change, their efficacy has not been thoroughly analyzed. We identified the key response variables within a lake that act as indicators of the effects of climate change on both the lake and the catchment. These variables reflect a wide range of physical, chemical, and biological responses to climate. However, the efficacy of the different indicators is affected by regional response to climate change, characteristics of the catchment, and lake mixing regimes. Thus, particular indicators or combinations of indicators are more effective for different lake types and geographic regions. The extraction of climate signals can be further complicated by the influence of other environmental changes, such as eutrophication or acidification, and the equivalent reverse phenomena, in addition to other land-use influences. In many cases, however, confounding factors can be addressed through analytical tools such as detrending or filtering. Lakes are effective sentinels for climate change because they are sensitive to climate, respond rapidly to change, and integrate information about changes in the catchment.

  • 2.
    Ahlberg, Per Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Sky konspiratörernas dimma - I: Uppsala Nya Tidning (UNT), 27 dec2008Other (Other (popular science, discussion, etc.))
  • 3.
    Ahmed, Engy
    et al.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Parducci, Laura
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Unneberg, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular Evolution.
    Ågren, Rasmus
    Chalmers Univ Technol, Dept Chem & Biol Engn, Sci Life Lab, SE-41296 Gothenburg, Sweden..
    Schenk, Frederik
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Rattray, Jayne E.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Univ Calgary, Biol Sci, 2500 Univ Dr NW, Calgary, AB, Canada..
    Han, Lu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics. Jilin Univ, Coll Life Sci, Ancient DNA Lab, Changchun, Jilin, Peoples R China..
    Muschitiello, Francesco
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Columbia Univ, Lamont Doherty Earth Observ, 61 Route 9NW, Palisades, NY USA..
    Pedersen, Mikkel W.
    Univ Cambridge, Dept Zool, Downing St, Cambridge CB2 3EJ, England..
    Smittenberg, Rienk H.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Yamoah, Kweku Afrifa
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Slotte, Tanja
    Stockholm Univ, Dept Ecol Environm & Plant Sci, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Wohlfarth, Barbara
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Archaeal community changes in Lateglacial lake sediments: Evidence from ancient DNA2018In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 181, p. 19-29Article in journal (Refereed)
    Abstract [en]

    The Lateglacial/early Holocene sediments from the ancient lake at Hasseldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hasseldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerod and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog. (C) 2017 Elsevier Ltd. All rights reserved.

  • 4.
    Albihn, Ann
    et al.
    National Veterinary Institute, Uppsala, Sweden.
    Gustafsson, Hans
    Swedish University of Agricultural Sciences.
    O’Hara Ruiz, Marilyn
    University of Illinois at Urbana-Champaign.
    38. Preparing for Climate Change2012In: Ecology and Animal Health / [ed] Leif Norrgren and Jeffrey Levengood, Uppsala: Baltic University Press , 2012, 1, p. 311-328Chapter in book (Other (popular science, discussion, etc.))
  • 5.
    Andersson, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala, The Baltic University Programme.
    Tol, Richard S.J.
    Max Planck Institute for Meteorology in Hamburg.
    Graham, L. Phil
    Swedish Meteorological and Hydrological Institute.
    Bergström, Sten
    Swedish Meteorological and Hydrological Institute.
    Rydén, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala, The Baltic University Programme.
    Azar, Christian
    University of Gothenburg.
    10. Impacts on the Global Atmosphere: Climate Change and Ozone Depletion2003In: Environmental Science: Understanding, protecting and managing the environment in the Baltic Sea Region / [ed] Lars Rydén, Pawel Migula and Magnus Andersson, Uppsala: Baltic University Press , 2003, 1, p. 294-323Chapter in book (Other (popular science, discussion, etc.))
  • 6.
    Andin, Caroline
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Synoptic Variability of Extreme Snowfall in the St. Elias Mountains, Yukon, Canada2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Glaciers of southwestern Yukon (Canada) and southeastern Alaska (USA) are presently experiencing high rates of annual mass loss. These high melt rates have mainly been investigated with respect to regional temperature trends, but comparatively little is known about how climate variations regulate snow accumulation on these glaciers. This study examines the synoptic weather patterns and air flow trajectories associated with extreme snowfall events in the central St. Elias Mountains (Yukon). The analyses are based on data retrieved from an automated weather station (AWS) between 2003 and 2012, which provide the longest continuous records of surface meteorological data ever obtained from this remote region.

    The AWS data reveal that 47 extreme snowfall events (> 27 cm per 12 hours) occurred during this period, of which 79 % took place during the cold season months. Air flow trajectories associated with these events indicate that a vast majority had their origin in the North Pacific south of 50°N. Less frequent were air masses with a source in the Aleutian Arc/Bering Sea region and the Gulf of Alaska, and in a few rare cases precipitating air was traced to continental source regions in Western Canada and Alaska. Composite maps of sea-level pressure and upper-level winds associated with extreme snowfall events revealed a frequent synoptic pattern with a low-pressure area centered over the Kenai Peninsula (Alaska), which drives strong southerly winds over the Gulf of Alaska towards the St. Elias Mountains. This pattern is consistent with AWS data wind recordings during snow storms. The most typical synoptic configurations of the North Pacific low-pressure area during extreme snowfall events are either elongated, split, or single-centered, and these situations represent possible seasonal analogues for the different states of the Aleutian Low in the subarctic North Pacific. However, neither the geographical position or intensity of negative sea-level pressure anomalies, nor surface pressure gradients associated with extreme snowfall events are good predictors of the actual snowfall SWE amounts recorded in the central St. Elias Mountains. Estimated snowfall and total precipitation gradients with altitude were confirmed to be much steeper (by up to ~30 %) on the continental side (Yukon), than on the coastal side (Alaska) of the St. Elias Mountains, reflecting the strong orographic division between the continental and coastal marine climatic regimes. Finally, patterns of 500-mb geopotential height anomalies associated with extreme snowfall events at Divide were compared with those associated with unusually high accumulation years in an ice core from the nearby Eclipse Icefield. Results confirm previous findings that associate high snow accumulation winters in this region with the presence of a strong dipole pressure structure between western North America and the Aleutian Low region, a structure which resembles the positive phase of the Pacific North American atmospheric circulation pattern. 

  • 7. Basirat, Farzad
    et al.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Perroud, H
    Université de Montpellier.
    Lofi, J.
    Université de Montpellier.
    Denchik, N.
    Université de Montpellier.
    Pezard, P.
    Université de Montpellier.
    Sharma, Prabhakar
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modeling gas transport in the shallow subsurface in the Maguelone field experiment2013Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Developing reliable monitoring techniques to detect and characterize CO2 leakage in shallow subsurface is necessary for the safety of any GCS project. To test different monitoring techniques, shallow injection-monitoring experiment have and are being carried out at the Maguelone, along the Mediterranean lido of the Gulf of Lions, near Montpellier, France. This experimental site was developed in the context of EU FP7 project MUSTANG and is documented in Lofi et al. (2012). Gas injection experiments are being carried out and three techniques of pressure, electrical resistivity and seismic monitoring have been used to detect the nitrogen and CO2 release in the near surface environment. In the present work we use the multiphase and multicomponent TOUGH2/EOS7CA model to simulate the gaseous nitrogen and CO2 transport of the experiments carried out so far. The objective is both to gain understanding of the system performance based on the model analysis as well as to further develop and validate modelling approaches for gas transport in the shallow subsurface, against the well-controlled data sets. Numerical simulation can also be used for the prediction of experimental setup limitations. We expect the simulations to represent the breakthrough time for the different tested injection rates. Based on the hydrogeological formation data beneath the lido, we also expect the vertical heterogeneities in grain size distribution create an effective capillary barrier against upward gas transport in numerical simulations.

  • 8.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Perroud, H
    Université de Montpellier.
    Lofi, J
    Université de Montpellier.
    Denchik, N
    Université de Montpellier.
    Pezard, P
    Université de Montpellier.
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University.
    Modeling gas transport in the shallow subsurface in the Maguelone field experiment2013Conference paper (Refereed)
    Abstract [en]

    Developing reliable monitoring techniques to detect and characterize CO2  leakage in shallow subsurface is necessary for the safety of any GCS project. To test different monitoring techniques, shallow injection-monitoring experiment have and are being carried out at the Maguelone, along the Mediterranean lido of the Gulf of Lions, near Montpellier, France. This experimental site was developed in the context of EU FP7 project MUSTANG and is documented in Lofi et al. (2012). Gas injection experiments are being carried out and three techniques of pressure, electrical resistivity and seismic monitoring have been used to detect the nitrogen and CO2  release in the near surface environment. In the present work we use the multiphase and multicomponent TOUGH2/EOS7CA model to simulate the gaseous nitrogen and CO2  transport of the experiments carried out so far. The objective is both to gain understanding of the system performance based on the model analysis as well as to further develop and validate modelling approaches for gas transport in the shallow subsurface, against the well-controlled data sets. Numerical simulation can also be used for the prediction of experimental setup limitations. We expect the simulations to represent the breakthrough time for the different tested injection rates. Based on the hydrogeological formation data beneath the lido, we also expect the vertical heterogeneities in grain size distribution create an effective capillary barrier against upward gas transport in numerical simulations.

  • 9. Basirat, Farzad
    et al.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Pore-scale modeling of wettability effects on CO2-brine displacement during geological storage2016Conference paper (Refereed)
    Abstract [en]

    Wetting properties of reservoir rocks and caprocks can significantly influence on sequestration of carbon dioxide in deep geological formations. Wettability impacts on the physical and chemical processes that are associated with injecting CO2 underground. Our aim is to understand how wetting properties influence two-phase flow of CO2 and brine in a pore scale domain. We use the phase field method to simulate the two-phase flow of CO2-brine in realistic porous domain geometry. Our focus is on clarifying the pore-scale fluid-fluid displacement mechanisms under different wetting conditions and to quantifying the effect of contact angle on macroscopic parameters such as residual brine saturation, capillary pressure, and specific interfacial area. We could show the phase field method can be applied to a complex porous medium with realistic reservoir permeability. Beside it was shown that it can deal with the conditions with large viscosity contrasts and large wettability (low contact angles) which are difficult to handle with direct numerical approaches. Our simulations results suggest wettability concept cannot be explained just by contact angles. Even though the wettability in pore-scale is defined as the contact angle, there is not any particular relation to link the contact angle to the residual saturations and distribution patterns of CO2 in porous domain. Beside the contact angle, the flow rate and basic properties of fluids which are represent in capillary number and mobility number definitions and also the geometry of porous media are describe the CO2-brine distributions.

  • 10.
    Bergström, Hans
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Nya svenska vindkarteringen2006Other (Other (popular scientific, debate etc.))
  • 11.
    Bergström, Hans
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Moberg, Anders
    Daily air temperature and pressure series for Uppsala 1722-19982002In: Climatic Change, no 53, p. 231-252Article in journal (Refereed)
  • 12. Bliss, Andrew
    et al.
    Hock, Regine
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Radic, Valentina
    Global response of glacier runoff to twenty-first century climate change2014In: J GEOPHYS RES-EARTH, ISSN 2169-9003, Vol. 119, no 4, p. 717-730Article in journal (Refereed)
    Abstract [en]

    The hydrology of many important river systems in the world is influenced by the presence of glaciers in their upper reaches. We assess the global-scale response of glacier runoff to climate change, where glacier runoff is defined as all melt and rain water that runs off the glacierized area without refreezing. With an elevation-dependent glacier mass balance model, we project monthly glacier runoff for all mountain glaciers and ice caps outside Antarctica until 2100 using temperature and precipitation scenarios from 14 global climate models. We aggregate results for 18 glacierized regions. Despite continuous glacier net mass loss in all regions, trends in annual glacier runoff differ significantly among regions depending on the balance between increased glacier melt and reduction in glacier storage as glaciers shrink. While most regions show significant negative runoff trends, some regions exhibit steady increases in runoff (Canadian and Russian Arctic), or increases followed by decreases (Svalbard and Iceland). Annual glacier runoff is dominated by melt in most regions, but rain is a major contributor in the monsoon-affected regions of Asia and maritime regions such as New Zealand and Iceland. Annual net glacier mass loss dominates total glacier melt especially in some high-latitude regions, while seasonal melt is dominant in wetter climate regimes. Our results highlight the variety of glacier runoff responses to climate change and the need to include glacier net mass loss in assessments of future hydrological change.

  • 13.
    Bokhorst, Stef
    et al.
    Norwegian Inst Nat Res NINA, FRAM High North Res Ctr Climate & Environm, POB 6606, N-9296 Tromso, Norway.;Vrije Univ Amsterdam, Dept Ecol Sci, De Boelelaan 1085, NL-1081 HV Amsterdam, Netherlands..
    Pedersen, Stine Hojlund
    Aarhus Univ, Dept Biosci, Arctic Res Ctr, Frederiksborgvej 399, DK-4000 Roskilde, Denmark..
    Brucker, Ludovic
    NASA, GSFC, Cryospher Sci Lab, Code 615, Greenbelt, MD 20771 USA.;Univ Space Res Assoc, Goddard Earth Sci Technol & Res Studies & Invest, Columbia, MD 21044 USA..
    Anisimov, Oleg
    State Hydrol Inst Roshydromet, 23 Second Line VO, St Petersburg 199053, Russia.;North East Fed Univ, Int Ctr Sci & Educ Best, Yakutsk, Russia..
    Bjerke, Jarle W.
    Norwegian Inst Nat Res NINA, FRAM High North Res Ctr Climate & Environm, POB 6606, N-9296 Tromso, Norway..
    Brown, Ross D.
    Environm Canada Ouranos, Div Climate Res, 550 Sherbrooke St West,19th Floor, Montreal, PQ H3A 1B9, Canada..
    Ehrich, Dorothee
    Univ Tromso, Dept Arctic & Marine Biol, N-9037 Tromso, Norway..
    Essery, Richard L. H.
    Univ Edinburgh, Sch GeoSci, Edinburgh, Midlothian, Scotland..
    Heilig, Achim
    Heidelberg Univ, Inst Environm Phys, Neuenheimer Feld 229, D-69120 Heidelberg, Germany..
    Ingvander, Susanne
    Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden..
    Johansson, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Johansson, Margareta
    Lund Univ, Dept Phys Geog & Ecosyst Sci, Solvegatan 12, S-22362 Lund, Sweden.;Royal Swedish Acad Sci, POB 50005, S-10405 Stockholm, Sweden..
    Jonsdottir, Ingibjorg Svala
    Univ Ctr Svalbard, POB 156, N-9171 Longyearbyen, Norway.;Univ Iceland, Fac Life & Environm Sci, Sturlugata 7, IS-101 Reykjavik, Iceland..
    Inga, Niila
    Leavas Sami Commun, Box 53, S-98121 Kiruna, Sweden..
    Luojus, Kari
    Finnish Meteorol Inst, Arctic Res, POB 503, Helsinki 00101, Finland..
    Macelloni, Giovanni
    CNR, IFAC CNR, Inst Appl Phys Nello Carrara, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, FI, Italy..
    Mariash, Heather
    Environm Canada, Natl Wildlife Res Ctr, 1125 Colonel By Dr, Ottawa, ON K1A 0H3, Canada..
    McLennan, Donald
    CHARS, 360 Albert St,Suite 1710, Ottawa, ON K1R 7X7, Canada..
    Rosqvist, Gunhild Ninis
    Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden.;Univ Bergen, Dept Earth Sci, N-5020 Bergen, Norway..
    Sato, Atsushi
    Natl Res Inst Earth Sci & Disaster Prevent, Snow & Ice Res Ctr, 187-16 Suyoshi, Nagaoka, Niigata 9400821, Japan..
    Savela, Hannele
    Univ Oulu, Thule Insitute, POB 7300, Oulu 90014, Finland..
    Schneebeli, Martin
    WSL Inst Snow & Avalanche Res SLF, Fluelastr 11, CH-7260 Davos, Switzerland..
    Sokolov, Aleksandr
    Russian Acad Sci, Arctic Res Stn, Inst Plant & Anim Ecol, Ural Branch, Labytnangi 629400, Russia.;State Org Yamal Nenets Autonomous Dist, Sci Ctr Arctic Studies, Salekhard, Russia..
    Sokratov, Sergey A.
    Moscow MV Lomonosov State Univ, Arctic Environm Lab, Fac Geog, Leninskie Gory 1, Moscow 119991, Russia..
    Terzago, Silvia
    Natl Res Council ISAC CNR, Inst Atmospher Sci & Climate, Corso Fiume 4, I-10133 Turin, Italy..
    Vikhamar-Schuler, Dagrun
    Norwegian Meteorol Inst, Div Model & Climate Anal, R&D Dept, Postboks 43, N-0313 Oslo, Norway..
    Williamson, Scott
    Univ Alberta, Dept Biol Sci, CW 405,Biol Sci Bldg, Edmonton, AB T6G 2E9, Canada..
    Qiu, Yubao
    Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Beijing 100094, Peoples R China.;Cold Reg Initiat, Grp Earth Observat, Geneva, Switzerland..
    Callaghan, Terry V.
    Lund Univ, Dept Phys Geog & Ecosyst Sci, Solvegatan 12, S-22362 Lund, Sweden.;Univ Sheffield, Dept Anim & Plant Sci, Sheffield S10 2TN, S Yorkshire, England.;Natl Res Tomsk Stated Univ, 36 Lenin Ave, Tomsk 634050, Russia..
    Changing Arctic snow cover: A review of recent developments and assessment of future needs for observations, modelling, and impacts2016In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 45, no 5, p. 516-537Article, review/survey (Refereed)
    Abstract [en]

    Snow is a critically important and rapidly changing feature of the Arctic. However, snow-cover and snowpack conditions change through time pose challenges for measuring and prediction of snow. Plausible scenarios of how Arctic snow cover will respond to changing Arctic climate are important for impact assessments and adaptation strategies. Although much progress has been made in understanding and predicting snow-cover changes and their multiple consequences, many uncertainties remain. In this paper, we review advances in snow monitoring and modelling, and the impact of snow changes on ecosystems and society in Arctic regions. Interdisciplinary activities are required to resolve the current limitations on measuring and modelling snow characteristics through the cold season and at different spatial scales to assure human well-being, economic stability, and improve the ability to predict manage and adapt to natural hazards in the Arctic region.

  • 14.
    Bylund Melin, Charlotte
    et al.
    Göteborg University.
    Legnér, Mattias
    Gotland University, School of Culture, Energy and Environment.
    Quantification, the link to relate climate-induced damage to indoor environments in historic buildings2013In: Climate for collections: Standards and uncertainties: Postprints of the Munich Climate Conference 7 to 9 November 2012 / [ed] Jonathan Ashley-Smith, Andreas Burmester and Melanie Eibl, 2013, p. 311-323Conference paper (Refereed)
    Abstract [en]

    This paper describes and applies a method to quantify and related damage of painted wooden pulpits in 16 churches in Gotland, Sweden, to both the current and the historical indoor climate of the twentieth century. In addition, it demonstrates that the energy used to heat a church in the past can be measured and the study alsopoints towards a relationship between damage and heat output. The results suggest that more damage is present in churches with a higher heat output and there is increased damage in churches using background heating compared to churches that do not. However, the method needs to be improved and a larger population is required to validate these results.

  • 15.
    Bäckström, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    The surface energy balance and climate in an urban park and its surroundings2005Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The world’s growing population and the increasing urbanization has made problems related to the urban heat island phenomenon to become more pronounced and since urban parks reduce the stress produced by the urban heat island they can be powerful tools in urban climate design. The temperature near the surface in a park is determined by the energy exchanges between the surface and the air above and it is therefore necessary to understand the surface energy balance of parks to intelligently manage their thermal microclimate. The objectives of this work were to study how the energy balances differ between different surfaces inside parks and in their built-up surroundings and to relate the surface energy balances to temperature differences.

    Measurements were conducted during three clear summer days in the park Humlegården located in central Stockholm. The measuring instruments were mounted on a cart, which was transported from observation site to observation site. The observation sites represented typical surfaces found in an urban park and its surroundings: one shaded and one open grass surface, one open and one shaded gravel surface and two paved surfaces representing streets running in the north-south and east-west directions respectively. The energy fluxes were calculated using air and surface temperatures, wind speed, air humidity and net radiation data.

    The most pronounced differences between the shaded and open surfaces in the park was that the shaded surfaces in general had smaller energy fluxes during daytime and that they had a downward directed sensible heat flux while the open surfaces had an upward directed sensible heat flux during the day. The most significant difference between the grass and the gravel surfaces in the park was that the grass surfaces had a bigger downward directed latent heat flux during the night and a smaller ground heat flux during both day and night. The largest differences between the surfaces inside the park and those in its built-up vicinities were that the paved surfaces had a larger upward directed sensible and ground heat flux during the night than the other surfaces. During the day the north-south directed paved site had a downward directed ground heat flux that was much larger than the ground heat flux for the other sites.

    The coolest site during the night was the non-shaded grass surface, which was the only site with a downward directed sensible heat flux during the night. Compared to the other nonshaded sites the open grass surface had a much smaller ground heat flux. Warmest sites during the night were the paved surfaces, which had a larger upward directed sensible and ground heat flux than the other surfaces. At the built-up sites the walls also contributed with sensible heat flux, i.e. the total sensible heat flux in the built-up area was larger than what comes from the street surface only. During the day the shaded surfaces in the park were the coolest sites. The shaded surfaces had less net radiation compared to the other non-shaded surfaces and were the only sites that had a downward directed sensible heat flux.

  • 16.
    Cardona Shokotko, Vanessa
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Theology, Department of Theology.
    Building Happy and Resilient Communities in the North of the European Union: A case study on Transition Movement in Sweden and its relationship with the EU2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When the world becomes drowned in multiple global problems and citizens do not see any real progressive solutions from their governments, they take the initiative in their own hands and start changing the world on their own. The Transition Town movement was born this way. It is a social movement which aims at building resilient local communities in response to climate change, peak oil and an unfair ecologically destructive economic system which is probably soon to break down. As a potentially strong actor of future social change, it is worth studying emerging local movements in Europe, and hopefully identifying new potentials for success of these grass-root innovations.The study, thus, aims to investigate the relation between the participants of the Transition Movement Sweden and the supranational/intergovernmental entity EU, which plays one of the key roles in economic, environmental and social aspects of Swedish citizens. By conducting interviews with participants of the movement in several Swedish cities, the nature of this relationship is being explored. Using the theory of Multi-Institutional Politics Approach the case study explains the connection between the movement and the EU.

  • 17.
    Charalampidis, Charalampos
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Geological Survey of Denmark and Greenland (GEUS).
    Climatology and firn processes in the lower accumulation area of the Greenland ice sheet2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Greenland ice sheet is the largest Northern Hemisphere store of fresh water, and it is responding rapidly to the warming climate. In situ observations document the changing ice sheet properties in the lower accumulation area, Southwest Greenland. Firn densities from 1840 meters above sea level retrieved in May 2012 revealed the existence of a 5.5-meter-thick, near-surface ice layer in response to the recent increased melt and refreezing in firn. As a consequence, vertical meltwater percolation in the extreme summer 2012 was inefficient, resulting in surface runoff. Meltwater percolated and refroze at six meters depth only after the end of the melt season. This prolonged autumn refreezing under the newly accumulated snowpack resulted in unprecedented firn warming with temperature at ten meters depth increased by more than four degrees Celsius. Simulations confirm that meltwater reached nine meters depth at most. The refrozen meltwater was estimated at 0.23 meters water equivalent, amounting to 25 % of the total 2012 ablation.

    A surface energy balance model was used to evaluate the seasonal and interannual variability of all surface energy fluxes at that elevation in the years 2009 to 2013. Due to the meltwater presence at the surface in 2012, the summer-averaged albedo was significantly reduced (0.71 in 2012; typically 0.78). A sensitivity analysis revealed that 71 % of the subsequent additional solar radiation in 2012 was used for melt, corresponding to 36 % of the total 2012 surface lowering. This interplay between melt and firn properties highlights that the lower accumulation area of the Greenland ice sheet will be responding rapidly in a warming climate.

    List of papers
    1. Automatic weather stations for basic and applied glaciological research
    Open this publication in new window or tab >>Automatic weather stations for basic and applied glaciological research
    Show others...
    2015 (English)In: Geological Survey of Denmark and Greenland Bulletin, ISSN 1811-4598, E-ISSN 1604-8156, Vol. 33, p. 69-72Article in journal (Refereed) Published
    Abstract [en]

    Since the early 1980s, the Geological Survey of Denmark and Greenland (GEUS) glaciology group has developed automatic weather stations (AWSs) and operated them on the Greenland ice sheet and on local glaciers to support glaciological research and monitoring projects (e.g. Olesen & Braithwaite 1989; Ahlstrøm et al. 2008). GEUS has also operated AWSs in connection with consultancy services in relation to mining and hydropower pre-feasibility studies (Colgan et al. 2015). Over the years, the design of the AWS has evolved, partly due to technological advances and partly due to lessons learned in the field. At the same time, we have kept the initial goal in focus: long-term, year-round accurate recording of ice ablation, snow depth and the physical parameters that determine the energy budget of glacierised surfaces. GEUS has an extensive record operating AWSs in the harsh Arctic environment of the diverse ablation areas of the Greenland ice sheet, glaciers and ice caps [...].

    The GEUS AWS model in use now is a reliable tool that is adapted to the environmental and logistical conditions of polar regions. It has a proven record of more than 150 stationyears of deployment in Greenland since its introduction in 2007–2008, and a success rate of c. 90% defined as the fraction of months with more than 80% valid air-temperature measurements over the total deployment time of the 25 stations in the field. The rest of this paper focuses on the technical aspects of the GEUS AWS, and provides an overview of its design and capabilities.

    Keywords
    Greenland, AWS, automatic weather stations
    National Category
    Climate Research Meteorology and Atmospheric Sciences
    Identifiers
    urn:nbn:se:uu:diva-280714 (URN)
    Projects
    Programme for Monitoring of the Greenland Ice Sheet (PROMICE)
    Available from: 2016-03-14 Created: 2016-03-14 Last updated: 2017-11-30
    2. Observed melt-season snowpack evolution on the Greenland ice sheet
    Open this publication in new window or tab >>Observed melt-season snowpack evolution on the Greenland ice sheet
    2015 (English)In: Geological Survey of Denmark and Greenland Bulletin, ISSN 1811-4598, E-ISSN 1604-8156, no 33, p. 65-68Article in journal (Refereed) Published
    Abstract [en]

    Due to recent warm and record-warm summers in Greenland (Nghiem et al. 2012), the melt of the ice-sheet surface and the subsequent runoff are increasing (Shepherd et al. 2012). About 84% of the mass loss from the Greenland ice sheet between 2009 and 2012 resulted from increased surface runoff (Enderlin et al. 2014). The largest melt occurs in the ablation zone, the low marginal area of the ice sheet (Van As et al. 2014), where melt exceeds wintertime accumulation and bare ice is thus exposed during each melt season. In the higher regions of the ice sheet (i.e. the accumulation area), melt is limited and the snow cover persists throughout the year. It is in the vast latter area that models struggle to calculate certain mass fluxes with accuracy. A better understanding of processes such as meltwater percolation and refreezing in snow and firn is crucial for more accurate Greenland ice sheet mass-budget estimates (Van Angelen et al. 2013).

    In May 2012, the field campaign ‘Snow Processes in the Lower Accumulation Zone’ was organized by the Geological Survey of Denmark and Greenland (GEUS) at the KAN_U automatic weather station (67 degrees N, 47 degrees W; 1840 m above sea level), which delivers data to the Programme for Monitoring of the Greenland Ice Sheet (PROMICE; Van As et al. 2013) and is one of the few weather stations located in the lower accumulation area of Greenland. During the expedition, we installed thermistor strings, firn compaction monitors and a snowpack analyzer; we drilled firn cores, performed firn radar measurements, gathered meteorological data, dug snow pits and performed dye-tracing experiments. One important objective of the campaign was to understand the thermal variability in the snowpack during the melt season by monitoring with high-precision temperature probes [...].

    Below, we present observations from the period 02 May to 23 July and interpret the atmosphere–surface interaction and its impact on the subsurface snow layers, with the goal to quantify refreezing in the Greenland accumulation area.

    Keywords
    snow, Greenland, ice sheet, percolation, refreezing
    National Category
    Earth and Related Environmental Sciences
    Identifiers
    urn:nbn:se:uu:diva-261333 (URN)000359477400016 ()
    Projects
    Stability and Variations of Arctic Land Ice (SVALI)Programme for Monitoring of the Greenland Ice Sheet (PROMICE)
    Available from: 2015-09-01 Created: 2015-09-01 Last updated: 2017-12-04
    3. Changing surface-atmosphere energy exchange and refreezing capacity of the lower accumulation area, West Greenland
    Open this publication in new window or tab >>Changing surface-atmosphere energy exchange and refreezing capacity of the lower accumulation area, West Greenland
    Show others...
    2015 (English)In: The Cryosphere, ISSN 1994-0416, E-ISSN 1994-0424, Vol. 9, no 6, p. 2163-2181Article in journal (Refereed) Published
    Abstract [en]

    We present 5 years (2009-2013) of automatic weather station measurements from the lower accumulation area (1840 m a.s.l. - above sea level) of the Greenland ice sheet in the Kangerlussuaq region. Here, the summers of 2010 and 2012 were both exceptionally warm, but only 2012 resulted in a strongly negative surface mass budget (SMB) and surface meltwater run-off. The observed run-off was due to a large ice fraction in the upper 10 m of firn that prevented meltwater from percolating to available pore volume below. Analysis reveals an anomalously low 2012 summer-averaged albedo of 0.71 (typically similar to 0.78), as meltwater was present at the ice sheet surface. Consequently, during the 2012 melt season, the ice sheet surface absorbed 28% (213 MJ m-2) more solar radiation than the average of all other years. A surface energy balance model is used to evaluate the seasonal and interannual variability of all surface energy fluxes. The model reproduces the observed melt rates as well as the SMB for each season. A sensitivity analysis reveals that 71% of the additional solar radiation in 2012 was used for melt, corresponding to 36% (0.64 m) of the 2012 surface lowering. The remaining 64% (1.14 m) of surface lowering resulted from high atmospheric temperatures, up to a + 2.6 degrees C daily average, indicating that 2012 would have been a negative SMB year at this site even without the melt-albedo feedback. Longer time series of SMB, regional temperature, and remotely sensed albedo (MODIS) show that 2012 was the first strongly negative SMB year, with the lowest albedo, at this elevation on record. The warm conditions of recent years have resulted in enhanced melt and reduction of the refreezing capacity in the lower accumulation area. If high temperatures continue, the current lower accumulation area will turn into a region with superimposed ice in coming years.

    Keywords
    energy balance, Greenland, ice sheet, melt, albedo, feedback, percolation, refreezing
    National Category
    Earth and Related Environmental Sciences
    Identifiers
    urn:nbn:se:uu:diva-275890 (URN)10.5194/tc-9-2163-2015 (DOI)000367523400010 ()
    Projects
    Stability and Variations of Arctic Land Ice (SVALI)Programme for Monitoring of the Greenland Ice Sheet (PROMICE)Greenland Analogue Project (GAP)
    Available from: 2016-02-08 Created: 2016-02-08 Last updated: 2017-11-30
    4. Greenland meltwater storage in firn limited by near-surface ice formation
    Open this publication in new window or tab >>Greenland meltwater storage in firn limited by near-surface ice formation
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    2016 (English)In: Nature Climate Change, ISSN 1758-678X, E-ISSN 1758-6798, Vol. 6, no 4, p. 390-393Article in journal, Letter (Refereed) Published
    Abstract [en]

    Approximately half of Greenland's current annual mass loss is attributed to runoff from surface melt. At higher elevations, however, melt does not necessarily equal runoff, because meltwater can refreeze in the porous near-surface snow and firn. Two recent studies suggest that all or most of Greenland's firn pore space is available for meltwater storage, making the firn an important buffer against contribution to sea level rise for decades to come. Here, we employ in situ observations and historical legacy data to demonstrate that surface runoff begins to dominate over meltwater storage well before firn pore space has been completely filled. Our observations frame the recent exceptional melt summers in 2010 and 2012, revealing significant changes in firn structure at different elevations caused by successive intensive melt events. In the upper regions (more than similar to 1,900 m above sea level), firn has undergone substantial densification, while at lower elevations, where melt is most abundant, porous firn has lost most of its capability to retain meltwater. Here, the formation of near-surface ice layers renders deep pore space difficult to access, forcing meltwater to enter an efficient surface discharge system and intensifying ice sheet mass loss earlier than previously suggested.

    Keywords
    Greenland, ice sheet, refreezing, percolation, melt, firn
    National Category
    Climate Research
    Identifiers
    urn:nbn:se:uu:diva-280716 (URN)10.1038/nclimate2899 (DOI)000373060000016 ()
    Projects
    Stability and Variations of Arctic Land Ice (SVALI)Programme for Monitoring of the Greenland Ice Sheet (PROMICE)
    Available from: 2016-03-14 Created: 2016-03-14 Last updated: 2017-11-30
    5. Thermal tracing of retained meltwater in the lower accumulation area of the Southwestern Greenland ice sheet
    Open this publication in new window or tab >>Thermal tracing of retained meltwater in the lower accumulation area of the Southwestern Greenland ice sheet
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    2016 (English)In: Annals of Glaciology, ISSN 0260-3055, E-ISSN 1727-5644, Vol. 57, no 72, p. 1-10, article id 6000021Article in journal (Refereed) Published
    Abstract [en]

    We present in situ firn temperatures from the extreme 2012 melt season in the southwestern lower accumulation area of the Greenland ice sheet. The upper 2.5 m of snow and firn was temperate during the melt season, when vertical meltwater percolation was inefficient due to a c. 5.5 m thick ice layer underlying the temperate firn. Meltwater percolation and refreezing beneath 2.5 m depth only occurred after the melt season. Deviations from temperatures predicted by pure conductivity suggest that meltwater refroze in discrete bands at depths of 2.0–2.5, 5.0–6.0 and 8.0–9.0 m. While we find no indication of meltwater percolation below 9 m depth or complete filling of pore volume above, firn at 10 and 15 m depth was respectively 4.2–4.5 degrees C and 1.7 degrees C higher than in a conductivity-only simulation. Even though meltwater percolation in 2012 was inefficient, firn between 2 and 15 m depth the following winter was on average 4.7 degrees C warmer due to meltwater refreezing. Our observations also suggest that the 2012 firn conditions were preconditioned by two warm summers and ice layer formation in 2010 and 2011. Overall, firn temperatures during the years 2009–13 increased by 0.6 degrees C.

    Keywords
    Greenland ice sheet, accumulation area, firn, percolation, refreezing, superimposed ice
    National Category
    Climate Research
    Identifiers
    urn:nbn:se:uu:diva-284357 (URN)10.1017/aog.2016.2 (DOI)000385592800002 ()
    Projects
    Stability and Variations of Arctic Land Ice (SVALI)Programme for Monitiring of the Greenland Ice Sheet (PROMICE)Greenland Analogue Project (GAP)
    Available from: 2016-04-17 Created: 2016-04-17 Last updated: 2017-11-30Bibliographically approved
    6. Regional climate-model performance in Greenland firn derived from in situ observations
    Open this publication in new window or tab >>Regional climate-model performance in Greenland firn derived from in situ observations
    Show others...
    2016 (English)In: Geological Survey of Denmark and Greenland Bulletin, ISSN 1811-4598, E-ISSN 1604-8156, Vol. 35, p. 75-78Article in journal (Refereed) Published
    Place, publisher, year, edition, pages
    Copenahgen, Denmark: , 2016
    Keywords
    Regional climate model, RCM, Greenland ice sheet, firn, automatic weather stations, AWS
    National Category
    Environmental Sciences
    Identifiers
    urn:nbn:se:uu:diva-284359 (URN)000383915800018 ()
    Projects
    Stability and Variations of Arctic Land Ice (SVALI)Programme for Monitoring of the Greenland Ice Sheet (PROMICE)Understanding and predicting non-linear change in the permeability of Greenland firn (RETAIN)
    Available from: 2016-04-17 Created: 2016-04-17 Last updated: 2017-11-30Bibliographically approved
  • 18.
    Charalampidis, Charalampos
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Institute for Marine and Atmospheric Research in Utrecht (IMAU).
    Response of the ice cap Langfjordjøkelen in northern Norway to climate change2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
  • 19.
    Charalampidis, Charalampos
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Geol Survey Denmark & Greenland GEUS, Oster Voldgade 10, DK-1350 Copenhagen K, Denmark.
    van As, Dirk
    Geol Survey Denmark & Greenland GEUS, Oster Voldgade 10, DK-1350 Copenhagen K, Denmark.
    Colgan, William T.
    Geol Survey Denmark & Greenland GEUS, Oster Voldgade 10, DK-1350 Copenhagen K, Denmark.; York Univ, Dept Earth & Space Sci & Engn, 4700 Keele St, Toronto, ON M3J 1P3, Canada.
    Fausto, Robert S.
    Geol Survey Denmark & Greenland GEUS, Oster Voldgade 10, DK-1350 Copenhagen K, Denmark.
    MacFerrin, Michael
    Univ Colorado, CIRES, 216 UCB, Boulder, CO 80309 USA.
    Machguth, Horst
    Geol Survey Denmark & Greenland GEUS, Oster Voldgade 10, DK-1350 Copenhagen K, Denmark.; Tech Univ Denmark, Arctic Technol Ctr ARTEK, Byg 118, DK-2800 Lyngby, Denmark.
    Thermal tracing of retained meltwater in the lower accumulation area of the Southwestern Greenland ice sheet2016In: Annals of Glaciology, ISSN 0260-3055, E-ISSN 1727-5644, Vol. 57, no 72, p. 1-10, article id 6000021Article in journal (Refereed)
    Abstract [en]

    We present in situ firn temperatures from the extreme 2012 melt season in the southwestern lower accumulation area of the Greenland ice sheet. The upper 2.5 m of snow and firn was temperate during the melt season, when vertical meltwater percolation was inefficient due to a c. 5.5 m thick ice layer underlying the temperate firn. Meltwater percolation and refreezing beneath 2.5 m depth only occurred after the melt season. Deviations from temperatures predicted by pure conductivity suggest that meltwater refroze in discrete bands at depths of 2.0–2.5, 5.0–6.0 and 8.0–9.0 m. While we find no indication of meltwater percolation below 9 m depth or complete filling of pore volume above, firn at 10 and 15 m depth was respectively 4.2–4.5 degrees C and 1.7 degrees C higher than in a conductivity-only simulation. Even though meltwater percolation in 2012 was inefficient, firn between 2 and 15 m depth the following winter was on average 4.7 degrees C warmer due to meltwater refreezing. Our observations also suggest that the 2012 firn conditions were preconditioned by two warm summers and ice layer formation in 2010 and 2011. Overall, firn temperatures during the years 2009–13 increased by 0.6 degrees C.

  • 20.
    Citterio, Michele
    et al.
    Geological Survey of Denmark and Greenland (GEUS).
    van As, Dirk
    Geological Survey of Denmark and Greenland (GEUS).
    Ahlstrøm, Andreas P.
    Geological Survey of Denmark and Greenland (GEUS).
    Andersen, Morten L.
    Geological Survey of Denmark and Greenland (GEUS).
    Andersen, Signe B.
    Geological Survey of Denmark and Greenland (GEUS).
    Box, Jason E.
    Geological Survey of Denmark and Greenland (GEUS).
    Charalampidis, Charalampos
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Geological Survey of Denmark and Greenland (GEUS).
    Colgan, William T.
    Geological Survey of Denmark and Greenland (GEUS).
    Fausto, Robert S.
    Geological Survey of Denmark and Greenland (GEUS).
    Nielsen, Søren
    Geological Survey of Denmark and Greenland (GEUS).
    Veicherts, Martin
    Geological Survey of Denmark and Greenland (GEUS).
    Automatic weather stations for basic and applied glaciological research2015In: Geological Survey of Denmark and Greenland Bulletin, ISSN 1811-4598, E-ISSN 1604-8156, Vol. 33, p. 69-72Article in journal (Refereed)
    Abstract [en]

    Since the early 1980s, the Geological Survey of Denmark and Greenland (GEUS) glaciology group has developed automatic weather stations (AWSs) and operated them on the Greenland ice sheet and on local glaciers to support glaciological research and monitoring projects (e.g. Olesen & Braithwaite 1989; Ahlstrøm et al. 2008). GEUS has also operated AWSs in connection with consultancy services in relation to mining and hydropower pre-feasibility studies (Colgan et al. 2015). Over the years, the design of the AWS has evolved, partly due to technological advances and partly due to lessons learned in the field. At the same time, we have kept the initial goal in focus: long-term, year-round accurate recording of ice ablation, snow depth and the physical parameters that determine the energy budget of glacierised surfaces. GEUS has an extensive record operating AWSs in the harsh Arctic environment of the diverse ablation areas of the Greenland ice sheet, glaciers and ice caps [...].

    The GEUS AWS model in use now is a reliable tool that is adapted to the environmental and logistical conditions of polar regions. It has a proven record of more than 150 stationyears of deployment in Greenland since its introduction in 2007–2008, and a success rate of c. 90% defined as the fraction of months with more than 80% valid air-temperature measurements over the total deployment time of the 25 stations in the field. The rest of this paper focuses on the technical aspects of the GEUS AWS, and provides an overview of its design and capabilities.

  • 21. Doyle, Sam H
    et al.
    Hubbard, Alun H
    Dow, Christine F
    Jones, Glenn A
    Fitzpatrick, Andrew
    Gusmeroli, Alessio
    Kulessa, Bernd
    Lindbäck, Katrin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Pettersson, Rickard
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Box, Jason E
    Ice tectonic deformation during the rapid in situ drainage of a supraglacial lake on the Greenland Ice Sheet2013In: The Cryosphere, ISSN 1994-0416, E-ISSN 1994-0424, Vol. 7, no 1, p. 129-140Article in journal (Refereed)
    Abstract [en]

    We present detailed records of lake discharge, ice motion and passive seismicity capturing the behaviour and processes preceding, during and following the rapid drainage of a 4 km2 supraglacial lake through 1.1-km-thick ice on the western margin of the Greenland Ice Sheet. Peak discharge of 3300 m3 s−1 coincident with maximal rates of vertical uplift indicates that surface water accessed the ice–bed interface causing widespread hydraulic separation and enhanced basal motion. The differential motion of four global positioning system (GPS) receivers located around the lake record the opening and closure of the fractures through which the lake drained. We hypothesise that the majority of discharge occurred through a 3-km-long fracture with a peak width averaged across its wetted length of 0.4 m. We argue that the fracture's kilometre-scale length allowed rapid discharge to be achieved by combining reasonable water velocities with sub-metre fracture widths. These observations add to the currently limited knowledge of in situ supraglacial lake drainage events, which rapidly deliver large volumes of water to the ice–bed interface.

  • 22.
    Drake, Alexandra
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Separating Acetate, Formate and MSA from natural samples using ion chromatography2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Anions from three short organic acids: acetate, formate and MSA are interesting to measure since they can be used for different environmental studies. The ion-chromatographer at the Department of Earth Sciences is currently not able to separate these three substances; therefore six new methods were developed in this project to solve this problem. Short organic test 5 ended up to be the best method, where acetate and formate were separated. The result was considered good, even if MSA were not separated.

    Method 5 was then tested on a couple of natural water, snow and ice samples. All these samples showed a larger amount of formate than of acetate, which in some cases was not even found. The results seemed plausible; not many of them were sticking out compared to others of the same phase. The shallowest sample from the Lomonosovfonna ice cap did however differ quite a lot in amount of formate compared with samples from other depths of this ice core; probably because of contamination which could have occurred at both the ice cap and in the lab during the handling of the samples.

    MSA can however also be measured if the amount of acetate and formate in the sample is known. This is done by adding known amounts of MSA to the same sample in subsequent runs to then be able to calculate the concentration of MSA in the sample. The problem with the use of this method is that the concentration of MSA needs to be high enough in contrast to acetate and formate in order to get reliable results, which was not the case in the samples measured in this project.

  • 23.
    Ekberg, Linus
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Social and Economic Geography.
    Världsarvet Karlskronas uppbyggnad: Hur ska det förvaltas och utvecklas?2016Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats är skriven för att visa hur ett av världsarven på vår jord har byggts upp och hur vi ska kunna förvalta, bevara och utveckla staden Karlskrona. För att kunna göra detta har Karlskronas historia studerats. Varför är den byggd som den är? Hur arbetar Karlskrona kommun för att minska skadorna i möjligt kommande naturkatastrofer? Uppsatsen innehåller kvalitativa metoder som bland annat är intervjuer med personer inom Karlskronas kommun. Uppsatsen har även skrivits med hjälp av litteraturgranskning för att få en bra uppfattning av vad som har gjort Karlskrona till ett världsarv.

    Resultatet av denna studie visar på hur Karlskrona kommer att utvecklas vidare som stad samt hur man ska lyckas bevara den kultur och historia som finns i staden. Resultatet visar vilket ansvar kommunen har för att bevara det som gör staden till ett världsarv. Hur Karlskrona arbetar för att skydda sig mot möjliga kommande naturkatastrofer kommer också att redovisas.

  • 24.
    Ekblom, Anneli
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, African and Comparative Archaeology. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala.
    Gillson, Lindsey
    Univ Cape Town, Rondebosch, South Africa.
    Notelid, Michel
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, African and Comparative Archaeology.
    Water flow, ecological dynamics, and management in the lower Limpopo Valley: a long‐term vie2017In: WIREs Water, ISSN 0935-879X, E-ISSN 2049-1948, Vol. 4, no 5, article id e1228Article in journal (Refereed)
    Abstract [en]

    In this contribution, we review long-term (millennial-decadal scale) river-flow changes, climate interactions, and interlinkage with vegetation dynamics, as well as society and policy, focusing on the lower Limpopo Valley (from the South African border through Mozambique). Drawing on paleoecological data, we address the valley's potential for defining critical ecological thresholds and managing an adaptive ecological landscape, by focusing on the dynamic relationship between different drivers (fire, hydrology, and grass/tree relationships). We briefly review the long-term interactions between water flow, climate variability, and society using archeological records and written sources. Lastly, we analyze the social and political context of water management, focusing on the last 100 years and transboundary water management. We also discuss planning and mitigation in relation to climate change and rainfall extremes that are projected to increase. It is stressed that forward-thinking policies must heed long-term climate variability, hydrology and biological and social impact and to plan and mitigate for environmental events. The discussion also brings to the fore the importance of an adaptable and equitable strategy in cross-border water sharing.

  • 25.
    Fagerlund, Fritjof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Ahlkrona, Josefin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Holmgren, Hanna
    Nielsen, Kristin
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Kreiss, Gunilla
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Analysis of boundary conditions in numerical simulations of geological CO2 storage2011In: 8th EGU General Assembly, Göttingen, Germany: Copernicus Publications , 2011, p. EGU2011-7410-Conference paper (Other academic)
    Abstract
  • 26.
    Fausto, Robert S.
    et al.
    Geological Survey of Denmark and Greenland (GEUS).
    van As, Dirk
    Geological Survey of Denmark and Greenland (GEUS).
    Antoft, Jens A.
    Box, Jason E.
    Geological Survey of Denmark and Greenland (GEUS).
    Colgan, William T.
    Geological Survey of Denmark and Greenland (GEUS).
    Andersen, Signe B.
    Geological Survey of Denmark and Greenland (GEUS).
    Ahlstrøm, Andreas P.
    Geological Survey of Denmark and Greenland (GEUS).
    Andersen, Morten L.
    Geological Survey of Denmark and Greenland (GEUS).
    Citterio, Michele
    Geological Survey of Denmark and Greenland (GEUS).
    Charalampidis, Charalampos
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Geological Survey of Denmark and Greenland (GEUS).
    Edelvang, Karen
    Geological Survey of Denmark and Greenland (GEUS).
    Haubner, Konstanze
    Geological Survey of Denmark and Greenland (GEUS).
    Larsen, Signe H.
    Geological Survey of Denmark and Greenland (GEUS).
    Veicherts, Martin
    Geological Survey of Denmark and Greenland (GEUS).
    Weidick, Anker
    Geological Survey of Denmark and Greenland (GEUS).
    Greenland ice sheet melt area from MODIS (2000–2014)2015In: Geological Survey of Denmark and Greenland Bulletin, ISSN 1811-4598, E-ISSN 1604-8156, Vol. 33, p. 57-60Article in journal (Refereed)
    Abstract [en]

    The Greenland ice sheet is an excellent observatory for global climate change. Meltwater from the 1.8 million km2 large ice sheet influences oceanic temperature and salinity, nutrient fluxes and global sea level (IPCC 2013). Surface reflectivity is a key driver of surface melt rates (Box et al. 2012). Mapping of different ice-sheet surface types provides a clear indicator of where changes in ice-sheet surface reflectivity are most prominent. Here, we present an updated version of a surface classification algorithm that utilises NASA’s Moderateresolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite to systematically monitor ice-sheet surface melt (Fausto et al. 2007). Our aim is to determine the areal extent of three surface types over the 2000–2014 period: glacier ice, melting snow (including percolation areas) and dry snow (Cuff ey & Paterson 2010). Monthly 1 km2 resolution surface-type grids can be downloaded via the CryoClim internet portal (www.cryoclim.net). In this report, we briefly describe the updated classification algorithm, validation of surface types and inter-annual variability in surface types.

  • 27. Ferrari, Maud C.O.
    et al.
    McCormick, Mark I.
    Munday, P. L.
    Meekan, Mark G.
    Dixson, Danielle D.
    Lönnstedt, Oona M.
    ARC Centre of Excellence for Coral Reef Studies, and School of Marine and Tropical Biology, James Cook University, Townsville, Australia.
    Chivers, Douglas P.
    Putting prey and predator into the CO2 equation - quantitative and qualitative effects of ocean acidification on predator-prey interactions2011In: Ecology Letters, ISSN 1461-023X, E-ISSN 1461-0248, Vol. 14, no 11, p. 1143-1148Article in journal (Refereed)
  • 28. Ferrari, Maud C.O.
    et al.
    McCormick, Mark I.
    Munday, Phil L.
    Meekan, Mark G.
    Dixson, Danielle D.
    Lönnstedt, Oona M.
    Chivers, Douglas P.
    Effects of ocean acidification on visual risk assessment by coral reef fishes2012In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 26, no 3, p. 553-558Article in journal (Refereed)
  • 29.
    Finné, Martin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, Classical archaeology and ancient history. Stockholm Univ, Dept Phys Geog, Stockholm, Sweden.;Navarino Environm Observ, Costa Navarino, Messinia, Greece..
    Holmgren, Karin
    Stockholm Univ, Dept Phys Geog, Stockholm, Sweden.;Navarino Environm Observ, Costa Navarino, Messinia, Greece.;Swedish Univ Agr Sci, Uppsala, Sweden..
    Shen, Chuan-Chou
    Natl Taiwan Univ, High Precis Mass Spectrometry & Environm Change L, Dept Geosci, Taipei, Taiwan..
    Hu, Hsun-Ming
    Natl Taiwan Univ, High Precis Mass Spectrometry & Environm Change L, Dept Geosci, Taipei, Taiwan..
    Boyd, Meighan
    Stockholm Univ, Dept Phys Geog, Stockholm, Sweden.;Navarino Environm Observ, Costa Navarino, Messinia, Greece.;Royal Holloway Univ London, Dept Earth Sci, Egham, Surrey, England..
    Stocker, Sharon
    Univ Cincinnati, Dept Class, 410 Blegen Lib, Cincinnati, OH USA..
    Late Bronze Age climate change and the destruction of the Mycenaean Palace of Nestor at Pylos2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 12, article id e0189447Article in journal (Refereed)
    Abstract [en]

    This paper offers new high-resolution oxygen and carbon isotope data from Stalagmite S1 from Mavri Trypa Cave, SW Peloponnese. Our data provide the climate background to the destruction of the nearby Mycenaean Palace of Nestor at Pylos at the transition from Late Helladic (LH) IIIB to LH IIIC, similar to 3150-3130 years before present (before AD 1950, hereafter yrs BP) and the subsequent period. S1 is dated by 24 U-Th dates with an averaged precision of +/- 26 yrs (2s), providing one of the most robust paleoclimate records from the eastern Mediterranean for the end of the Late Bronze Age (LBA). The delta O-18 record shows generally wetter conditions at the time when the Palace of Nestor at Pylos was destroyed, but a brief period of drier conditions around 3200 yrs BP may have disrupted the Mycenaean agricultural system that at the time was likely operating close to its limit. Gradually developing aridity after 3150 yrs BP, i.e. subsequent to the destruction, probably reduced crop yields and helped to erode the basis for the reinstitution of a central authority and the Palace itself.

  • 30.
    Finné, Martin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Holmgren, Karin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Sundqvist, Hanna S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Weiberg, Erika
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, Classical archaeology and ancient history.
    Lindblom, Michael
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, Classical archaeology and ancient history.
    Climate in the eastern Mediterranean, and adjacent regions, during the past 6000 years: A review2011In: Journal of Archaeological Science, ISSN 0305-4403, E-ISSN 1095-9238, Vol. 38, no 12, p. 3153-3173Article, review/survey (Refereed)
    Abstract [en]

    The eastern Mediterranean, with its long archaeological and historical records, provides a unique opportunity to study human responses to climate variability. We review paleoclimate data and reconstructions from the region with a focus on the last 6000 years. We aim to provide an up-to-date source of information on climate variability and to outline present limitations and future opportunities. The review work is threefold: (1) literature review, (2) spatial and temporal analysis of proxy records, and (3) statistical estimation of uncertainties in present paleoclimate reconstructions (temperature, °C). On a regional scale the review reveals a wetter situation from 6000 to 5400 yrs BP (note: all ages in this paper are in calibrated years before present (i.e. before 1950), abbreviated yrs BP, unless otherwise stated). This is followed by a less wet period leading up to one of fully-developed aridity from c. 4600 yrs BP. There is a need for more high-resolution paleoclimate records, in order to (i) better understand regional patterns and trends versus local climate variability and to (ii) fill the gap of data from some regions, such as the Near East, Greece and Egypt. Further, we evaluate the regional occurrence of a proposed widespread climate event at 4200 yrs BP. This proposed climate anomaly has been used to explain profound changes in human societies at different locations in the region around this time. We suggest that although aridity was widespread around 4200 yrs BP in the eastern Mediterranean region, there is not enough evidence to support the notion of a climate event with rapidly drying conditions in this region.

  • 31.
    Fiola, Markus L.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Influence of Sample Preparation on Portable XRF-analyses of Aeolian Sediments: a Case Study2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The geochemical composition of aeolian sediments like windblown dust particles is of major importance for the exploration of dust origin and weathering conditions. This allows for the reconstruction of dust transport pathways and thus wind directions and palaeoclimate conditions. The loess deposits of the Carpathian Basin are the most complete terrestrial sediment climate archive in Europe, yet their development is still not fully understood. With the advancement of accurate field portable X-ray fluorescence (XRF) spectrometers, field applications have become possible, allowing in-situ geochemical analysis and potential advances in understanding the source of Carpathian Basin loess. However, previous work has failed to address the question of sample preparation and device interchangeability in the context of loess analyses.

    This study uses both Bruker Tracer 5i and Titan S1, as well as secondary data obtained with an Ametek SpectroXepos, to investigate sample preparation influences on aeolian sediment samples from Irig (Serbia) and Madaras (Hungary). Results showed that although absolute values deviate substantially between devices using different calibrations, some elemental ratios like Ca/Ti or Rb/Sr can still be compared when only relative changes are interpreted. Absolute concentrations of light elements, such as magnesium and calcium, were strongly influenced by milling or acid treatment. Absolute concentrations of light elements were also strongly influenced by changes in sample moisture, whereas the effect on the absolute concentrations of heavier elements was comparably small. Results also show that the influence of sample moisture needs to be considered when computing paleoclimatic indicator ratios involving aluminium or strontium, as sample moisture has a strong effect on the absolute concentration of these elements.

    Most deviations in measured absolute concentrations between untreated and prepared samples were attributed to the special nature of compositional data and could be removed through the application of additive or centred log-ratio transformations. This highlights the importance of considering the closure effect, using proper and robust statistical analyses in sediment provenance research.The geochemical data provided in this study shed light on dust provenance and the paleoclimatic development of the southeast European loess and highlight the effects of analysis technique on interpretation of this geochemical data.

    The full text will be freely available from 2019-08-01 08:01
  • 32.
    Ghaffar, Nausherwan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    What determines a Climate Pledge?: The case of China and the EU2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    This thesis compares two pledges to reduce or delimit greenhouse gas emissions by two keynegotiation parties in conjunction with the United Nations Conference of Parties held atCopenhagen in December 2009. The two parties covered here are the EU and China. Thetwo key questions that I have dealt with are: what do the conditions and targets in thepledge actually mean? and what were the driving forces behind each pledge?. I have relied,mostly on qualitative research methods, including interviews.The key points to note are that the EU and China, both, leave some prominent areas ofconcern open to interpretation. This seems to be to allow for future political manoeuvring.Furthermore, the EU (when comparing the pledges) comes out to be much more ambitiousthan China in terms of cutting carbon emissions (based on various assumptions). As for thedriving forces, various similarities and differences are noted. Yet, what one issue means toone party might mean something completely different for the other.

  • 33.
    Grinsted, Aslak
    et al.
    State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, China.
    Moore, John C
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Jevrejeva, Svetlana
    State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, China.
    Homogeneous record of Atlantic hurricane surge threat since 19232012In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 48, p. 19601-19605Article in journal (Refereed)
    Abstract [en]

    Detection and attribution of past changes in cyclone activity are hampered by biased cyclone records due to changes in observational capabilities. Here we construct an independent record of Atlantic tropical cyclone activity on the basis of storm surge statistics from tide gauges. We demonstrate that the major events in our surge index record can be attributed to landfalling tropical cyclones; these events also correspond with the most economically damaging Atlantic cyclones. We find that warm years in general were more active in all cyclone size ranges than cold years. The largest cyclones are most affected by warmer conditions and we detect a statistically significant trend in the frequency of large surge events (roughly corresponding to tropical storm size) since 1923. In particular, we estimate that Katrina-magnitude events have been twice as frequent in warm years compared with cold years (P < 0.02).

  • 34. Guglielmin, Mauro
    et al.
    Donatelli, Marco
    Semplice, Matteo
    Serra Capizzano, Stefano
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Ground surface temperature reconstruction for the last 500 years obtained from permafrost temperatures observed in the Stelvio Share borehole, Italian Alps2017In: Climate of the Past Discussions, ISSN 1814-9340, E-ISSN 1814-9359Article in journal (Other academic)
  • 35.
    Gustafsson, Eric
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Institutionen för mark och miljö (SLU).
    Dimensionering av markavvattningssystem för jordbruksmark i nuvarande och framtida klimat: En pilotstudie på olika typjordar2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    About half of Sweden’s cultivated lands are estimated to be using artificial subsurface drainage. Earlier studies have shown that several of these drainage systems are obsolete and ill-equipped to handle the present climate conditions. Sweden has used a drain depth of 1.2 meters for the drainage systems as a guideline value, although studies have suggested it is necessary to be re-evaluated. Poorly dimensioned drainage systems in combination with an expected increase in precipitation due to climate change puts Sweden into challenges to adapt current drainage systems for the future. A well-drained soil is a crucial fundament to minimize nitrogen-losses and maximize crop yields to sustain a growing population.

    The aim was to model two different types of soils’ drainage systems with the hydrology model DRAINMOD and adapt these for today’s and the future’s climate.

    DRAINMOD simulates the hydrology of a soil for long periods of climatological records. The model predicts water table, soil water regime, drainage, run-off and crop yields associated with a certain drainage system design. Several different drainage depths and spaces for each of the two soils were analysed and evaluated. For the field located in the county of Östergötland, a drainage depth of 1.2 m and spacing of 25–50 m were sufficient to minimize drainage losses and maximize crop yield. Furthermore, a depth of 0.9 m and spacings of 20–50 m would be sufficient for the second field located in the county of Skåne.

  • 36.
    Hansson, Caroline
    SLU, Institutionen för energi och teknik,.
    Analys av skillnader och likheter i EU-länders långsiktiga klimatstrategier2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The international climate negotiations are to find solutions to stabilize concentrations of greenhouse gases in the atmosphere and to achieve the two degree target. To achieve this goal there are various emission targets to aim for. One is a ceiling in which each country must not emit more than two tons CO2-ekv/capita per year for two degree target to be achieved. Another emission target is to reduce national emissions by a certain percentage. EU's part in the reduction is 80-95 % by 2050.

    As a step towards the target in March 2011 the European Union launched a roadmap to a low carbon economy. It sets out measures for five different sectors and the size of the emission reductions estimated for each sector. The energy sector is the sector that is expected to decrease most, and is expected to almost reach a zero level. Also housing and service is expected to reduce their emissions significantly. The agricultural sector is the sector that is expected to decrease the least. The roadmap urges each member country to develop a national roadmap for 2050. This examination work aims to analyze a number of national roadmaps to find out what resources and opportunities that have a significant impact on the roadmap.

    The results show that all the countries have adopted the same target as the EU, namely 80%. If all countries reduce by 80% by 2050, only Slovenia will reach the limit of two tons CO2-ekv/capita, all other countries are above the limit. The ways to reduce emissions are primarily low-carbon energy technologies, energy efficiency and increased use of electricity because it has the potential to be emission-free. Wind power is the technology that many of the countries are choosing to invest in, mainly at sea when the space on land is limited. Nuclear power is an energy source where the opinion is split in two. Some countries consider it a good low-carbon energy source and favorable climate, while others argue that it is uncertain in both economy and safety. CCS (carbon capture and storage) is taken up by all the countries studied as a possible measure to reduce emissions. To reduce use of fossil fuels in the transport sector, it is primarily biofuels and electricity to be used.

    Conclusions to be drawn from this work are that CCS with the right conditions will be on a larger scale in 2050 than today. Electric cars play a big role in the transport sector. Nuclear power and renewable alternatives are techniques that will play a major role in the energy 2050. To reach the two-degree target requires international agreements that also reduce the risk of carbon leakage.

  • 37.
    Henderiks, Jorijntje
    et al.
    Stockholm University.
    Pagani, Mark
    Coccolithophore cell size and the Paleogene decline in atmospheric CO22008In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 269, no 3-4, p. 576-584Article in journal (Refereed)
  • 38.
    Henderiks, Jorijntje
    et al.
    Stockholm University.
    Pagani, Mark
    Refining ancient carbon dioxide estimates: Significance of coccolithophore cell size for alkenone-based pCO2 records2007In: Paleoceanography, ISSN 0883-8305, E-ISSN 1944-9186, Vol. 22, no 3, p. PA3202-Article in journal (Refereed)
  • 39.
    Hidalgo, H. G.
    et al.
    Univ Costa Rica, Sch Phys, San Pedro 2060, Costa Rica.;Univ Costa Rica, Ctr Geophys Res, San Pedro 2060, Costa Rica..
    Alfaro, E. J.
    Univ Costa Rica, Sch Phys, San Pedro 2060, Costa Rica.;Univ Costa Rica, Ctr Geophys Res, San Pedro 2060, Costa Rica.;Univ Costa Rica, Ctr Res Marine Sci & Limnol, San Pedro 2060, Costa Rica..
    Quesada Montano, Beatriz
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Costa Rica, Ctr Geophys Res, San Pedro 2060, Costa Rica..
    Observed (1970-1999) climate variability in Central America using a high-resolution meteorological dataset with implication to climate change studies2017In: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 141, no 1, p. 13-28Article in journal (Refereed)
    Abstract [en]

    High spatial resolution of precipitation (P) and average air temperature (Tavg) datasets are ideal for determining the spatial patterns associated with large-scale atmospheric and oceanic indexes, and climate change and variability studies, however such datasets are not usually available. Those datasets are particularly important for Central America because they allow the conception of climate variability and climate change studies in a region of high climatic heterogeneity and at the same time aid the decisionmaking process at the local scale (municipalities and districts). Tavg data from stations and complementary gridded datasets at 50 km resolution were used to generate a high-resolution (5 km grid) dataset for Central America from 1970 to 1999. A highresolution P dataset was used along with the new Tavg dataset to study climate variability and a climate change application. Consistently with other studies, it was found that the 1970-1999 trends in P are generally non-significant, with the exception of a few small locations. In the case of Tavg, there were significant warming trends in most of Central America, and cooling trends in Honduras and northern Panama. When the sea surface temperature anomalies between the Tropical Pacific and the Tropical Atlantic have different (same) sign, they are a good indicator of the sign of P (Tavg) annual anomalies. Even with non-significant trends in precipitation, the significant warming trends in Tavg in most of Central America can have severe consequences in the hydrology and water availability of the region, as the warming would bring increases in evapotranspiration, drier soils and higher aridity.

  • 40.
    Hoang, Cham
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Stangefelt, Moa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Possible Impact from Alaskan Forest Fires on Glaciers of St. Elias Mountains, Yukon Canada2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    How great potential effect does the Black carbon emitted from the boreal forest fire region of Alaska have on the retreating glaciers of the St. Elias Mountains? In this study climate and forest fire history data of Alaska was run in the HYSPLIT wind trajectory model to generate trajectories originated from large occurring fires in Alaska from 2005 to 2014. Results show a small percentage of trajectories passing the St. Elias Mountains and an expected pattern of a correlation between passing trajectories and density of amount forest fires. Interdisciplinary climate research is indicating an increase in global temperatures with consequences such as an upswing of forest fires in the Northern Hemisphere. Inner Alaska is fire prone due to a combination of prevailing droughts during the summer season and frequent lightning ignition as a result from homogeneous vegetation and topography. Downwind from Alaska’s forest fire region is the ice field of the St. Elias Mountains, these glaciers are one of the fastest retreating due to increasing global temperatures and possible deposition of soot from Alaskan forest fires. Forest fire emits black carbon, which when deposited on snow or ice surfaces will decrease the albedo and accelerate the melting rate. Previous studies on ice cores from the St. Elias have investigated traces of combustion products from biomass burning. This indicates a possible record of historic forest fires in ice cores. The small percentage of passing trajectories in this study suggests that most large forest fires in Alaska might not be registered in the St. Elias ice cores.

  • 41.
    Hock, Regine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Huss, Matthias
    ETH Zurich.
    A new model for global glacier change and sea-level rise2015In: frontiers in earth science, Vol. 3, p. 1-22, article id 54Article in journal (Refereed)
    Abstract [en]

    The anticipated retreat of glaciers around the globe will pose far-reaching challenges to the management of fresh water resources and significantly contribute to sea-level rise within the coming decades. Here, we present a new model for calculating the twenty-first century mass changes of all glaciers on Earth outside the ice sheets. The Global Glacier Evolution Model (GloGEM) includes mass loss due to frontal ablation at marine-terminating glacier fronts and accounts for glacier advance/retreat and surface elevation changes. Simulations are driven with monthly near-surface air temperature and precipitation from 14 Global Circulation Models forced by RCP2.6, RCP4.5, and RCP8.5 emission scenarios. Depending on the scenario, the model yields a global glacier volume loss of 25–48% between 2010 and 2100. For calculating glacier contribution to sea-level rise, we account for ice located below sea-level presently displacing ocean water. This effect reduces the glacier contribution by 11–14%, so that our model predicts a sea-level equivalent (multi-model mean ±1 standard deviation) of 79±24 mm (RCP2.6), 108±28 mm (RCP4.5), and 157±31 mm (RCP8.5). Mass losses by frontal ablation account for 10% of total ablation globally, and up to ∼30% regionally. Regional equilibrium line altitudes are projected to rise by ∼100–800 m until 2100, but the effect on ice wastage depends on initial glacier hypsometries.

  • 42.
    Häkkinen, Kirsti
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Akrami, Nazar
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Ideology and climate change denial2014In: Personality and Individual Differences, ISSN 0191-8869, E-ISSN 1873-3549, Vol. 70, p. 62-65Article in journal (Refereed)
    Abstract [en]

    Examining the relation between ideological variables and climate change denial, we found social dominance orientation (SDO) to outperform right-wing authoritarianism and left-right political orientation in predicting denial (Study 1 and 2). In Study 2, where we experimentally altered the level of denial by a newscast communicating supporting evidence for climate change, we demonstrated that the relation between the ideology variables and denial remains stable across conditions (newscast vs. control). Thus, the results showed that denial can be altered by communicating climate change evidence regardless of peoples' position on ideology variables, in particular social dominance. We discuss the outcome in terms of core elements of SDO - dominance and system-justification motives - and encourage researchers on climate change denial to focus on these elements. 

  • 43.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Future coal production outlooks in the IPCC Emission Scenarios: Are they plausible?2011In: Energy and Environment, ISSN 0958-305X, E-ISSN 2048-4070, Vol. 22, no 7, p. 837-858Article in journal (Refereed)
    Abstract [en]

    Anthropogenic climate change caused by CO2 emissions is strongly linked to the future energy production, specifically coal. The Special Report on Emission Scenarios (SRES) contains 40 scenarios for future fossil fuel production and is used by the IPCC to assess future climate change. This study examines the SRES coal production outlooks. Fundamental assumptions regarding coal availability and production in SRES was also compared with recent studies on reasonable future production outlooks. It was found that SRES puts unreasonable expectation on just a few countries. Is it reasonable to expect that China, already accounting for 46% of the global output, would increase their production by a factor of 8 over the next 90 years, as implied by certain SRES scenarios? It is concluded that SRES is underpinned by a paradigm of perpetual growth and technological optimism as well as old and outdated resource estimates. This has resulted in overoptimistic production outlooks.

  • 44.
    Höök, Mikael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Sivertsson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Aleklett, Kjell
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Validity of the fossil fuel production outlooks in the IPCC Emission Scenarios2010In: Natural Resources Research, ISSN 1520-7439, E-ISSN 1573-8981, Vol. 19, no 2, p. 63-81Article in journal (Refereed)
    Abstract [en]

    Anthropogenic global warming caused by CO2 emissions is strongly and fundamentally linked to future energy production. The Special Report on Emission Scenarios (SRES) from 2000 contains 40 scenarios for future fossil fuel production and is used by the IPCC to assess future climate change. Previous scenarios were withdrawn after exaggerating one or several trends. This study investigates underlying assumptions on resource availability and future production expectations to determine whether exaggerations can be found in the present set of emission scenarios as well.

    It is found that the SRES unnecessarily takes an overoptimistic stance and that future production expectations are leaning towards spectacular increases from present output levels. In summary, we can only encourage the IPCC to involve more resource experts and natural science in future emission scenarios. The current set, SRES, is biased toward exaggerated resource availability and unrealistic expectations on future production outputs from fossil fuels.

  • 45.
    Höök, Mikael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Global Energy Systems.
    Tang, Xu
    China University of Petroleum - Beijing.
    Depletion of fossil fuels and anthropogenic climate change: a review2013In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 52, p. 797-809Article, review/survey (Refereed)
    Abstract [en]

    Future scenarios with significant anthropogenic climate change also display large increases in world production of fossil fuels, the principal CO2 emission source. Meanwhile, fossil fuel depletion has also been identified as a future challenge. This chapter reviews the connection between these two issues and concludes that limits to availability of fossil fuels will set a limit for mankind’s ability to affect the climate. However, this limit is unclear as various studies have reached quite different conclusions regarding future atmospheric CO2 concentrations caused by fossil fuel limitations.

    It is concluded that the current set of emission scenarios used by the IPCC and others is perforated by optimistic expectations on future fossil fuel production that are improbable or even unrealistic. The current situation, where climate models largely rely on emission scenarios detached from the reality of supply and its inherent problems is problematic. In fact, it may even mislead planners and politicians into making decisions that mitigate one problem but make the other one worse. It is important to understand that the fossil energy problem and the anthropogenic climate change problem are tightly connected and need to be treated as two interwoven challenges necessitating a holistic solution.

  • 46.
    Inceoglu, F.
    et al.
    Aarhus Univ, Dept Phys & Astron, Stellar Astrophys Ctr, Aarhus, Denmark.;Aarhus Univ, Dept Geosci, Aarhus, Denmark..
    Knudsen, M. F.
    Aarhus Univ, Dept Geosci, Aarhus, Denmark..
    Olsen, J.
    Aarhus Univ, Dept Phys, AMS, Dating Ctr 14C, Aarhus, Denmark..
    Karoff, C.
    Aarhus Univ, Dept Phys & Astron, Stellar Astrophys Ctr, Aarhus, Denmark.;Aarhus Univ, Dept Geosci, Aarhus, Denmark..
    Herren, P. -A
    Schwikowski, M.
    Paul Scherrer Inst, Villigen, Switzerland.;Univ Bern, Oeschger Ctr Climate Change Res, Bern, Switzerland..
    Aldahan, Ala
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. United Arab Emirates Univ, Dept Geol, Al Ain, U Arab Emirates..
    Possnert, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, För teknisk-naturvetenskapliga fakulteten gemensamma enheter, Tandem Laboratory.
    A continuous ice-core Be-10 record from Mongolian mid-latitudes: Influences of solar variability and local climate2016In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 437, p. 47-56Article in journal (Refereed)
    Abstract [en]

    High-resolution Be-10 records used for studies of detailed changes in atmospheric Be-10 production rates predominantly derive from polar ice cores. In this study, we present the first Be-10 record from a mid latitude ice core. The ice core derives from the Tsambagarav mountain range located in the Mongolian Altai region. The new Be-10 concentration record spans the period from AD 1550 to 2009, while the flux record extends from AD 1816 to 2009. The Be-10 concentration in the Tsambagarav ice core ranges between similar to 1.5 x 10(4) and similar to 10 x 10(4) atoms g(-1), whereas the Be-10 flux changes from similar to 0.02 to similar to 0.15 atoms cm(-2) s(-1) The average Be-10 flux at Tsambagarav is four times higher than the average Be-10 flux recorded in the NGRIP and Dome Fuji ice cores, which is in accordance with model predictions. In general, the long-term trends observed in the Tsambagarav Be-10 concentration and flux records are reasonably similar to those observed in the NGRIP ice core. A comparison between the Tsambagarav Be-10 record, group sunspot numbers (GSNs), and solar modulation potentials based on C-14 in tree rings suggests that the Maunder Minimum was associated with a prolonged maximum in Be-10 concentrations at Tsambagarav, whereas the Dalton Minimum was associated with a minor increase in the Be-10 concentration and flux that was delayed relative to the primary minimum in GSNs. The sulphate record from Tsambagarav shows that large positive anomalies in the sulphate concentration are associated with negative anomalies in the Be-10 concentration. A concurrent positive sulphate anomaly may explain why the main phase of the Dalton Minimum is subdued in the Be-10 record from Tsambagaray. Spectral analysis indicates that the 11-yr solar-cycle signal may have influenced the new Be-10 record, but the evidence supporting a direct link is ambiguous. Local and regional climatic changes, such as cyclonic versus anticyclonic conditions and related storm tracks, most likely played a significant role for the Be-10 deposition in the Tsambagarav region.

  • 47.
    Jevrejeva, S
    et al.
    Beijing Normal University.
    Moore, John C
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Grinsted, A.
    Potential for bias in 21st century semiempirical sea level projections2012In: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 117, p. D20116-Article in journal (Refereed)
    Abstract [en]

    We examine the limitations of a semiempirical model characterized by a sea level projection of 73 cm with RCP4.5 scenario by 2100. Calibrating the model with data to 1990 and then simulating the period 1993–2009 produces sea level in close agreement with acceleration in sea level rise observed by satellite altimetry. Nonradiative forcing contributors, such as long-term adjustment of Greenland and Antarctica ice sheets since Last Glacial Maximum, abyssal ocean warming, and terrestrial water storage, may bias model calibration which, if corrected for, tend to reduce median sea level projections at 2100 by 2–10 cm, though this is within the confidence interval. We apply the semiempirical approach to simulate individual contributions from thermal expansion and small glacier melting. Steric sea level projections agree within 3 cm of output from process-based climate models. In contrast, semiempirical simulation of melting from glaciers is 26 cm, which is twice large as estimates from some process-based models; however, all process models lack simulation of calving, which likely accounts for 50% of small glacier mass loss worldwide. Furthermore, we suggest that changes in surface mass balance and dynamics of Greenland ice sheet made contributions to the sea level rise in the early 20th century and therefore are included within the semiempirical model calibration period and hence are included in semiempirical sea level projections by 2100. Antarctic response is probably absent from semiempirical models, which will lead to a underestimate in sea level rise if, as is probable, Antarctica loses mass by 2100.

  • 48.
    Jidetorp, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Sjöars känslighet för klimatförändringar – vilka faktorer påverkar?2006Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Earths climate is changing at a higher rate, i.e between 1861 and 1994 the annual mean temperature in Scandinavia increased with 0,68º C and according to recent climate models the annual mean temperature is likely to rise with another 3º C during this century.

    A warmer climate in many ways is associated with changing conditions for lake ecosystems. An expected higher water temperature and a stronger summer stratification of the water column increases the risk of anoxic conditions at the lake bottom. Thus anoxic conditions are likely to cause a phosphate leakage from the sediment, i.e. a higher internal loading of phosphate.

    In this project, the extremely warm summer of 2002 has been used as an example for a possible scenario for a future climate. By comparing levels of phosphorus in the summer of 2002 with a ten-year median value, a phosphorus related sensitivity to climate change has been analyzed for 55 Swedish lakes. This sensitivity has then been related to several parameters of which in particular the lake morphometry and the land use in the catchment of the lake influenced the climatic sensitivity of the lake to climatic change.

  • 49. Jones, Phil D.
    et al.
    Briffa, K.R.
    Osborn, T.J.
    Moberg, Anders
    Bergström, Hans
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Relationships between circulation strength and the variability of growing-season and cold-season climate in northern and central Europe2002In: The Holocene, Vol. 12, no 6, p. 643-656Article in journal (Refereed)
  • 50.
    Jungqvist, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Oni, Stephen K.
    Teutschbein, Claudia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Futter, Martyn N.
    Effect of Climate Change on Soil Temperature in Swedish Boreal Forests2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 4, p. e93957-Article in journal (Refereed)
    Abstract [en]

    Complex non-linear relationships exist between air and soil temperature responses to climate change. Despite its influence on hydrological and biogeochemical processes, soil temperature has received less attention in climate impact studies. Here we present and apply an empirical soil temperature model to four forest sites along a climatic gradient of Sweden. Future air and soil temperature were projected using an ensemble of regional climate models. Annual average air and soil temperatures were projected to increase, but complex dynamics were projected on a seasonal scale. Future changes in winter soil temperature were strongly dependent on projected snow cover. At the northernmost site, winter soil temperatures changed very little due to insulating effects of snow cover but southern sites with little or no snow cover showed the largest projected winter soil warming. Projected soil warming was greatest in the spring (up to 4°C) in the north, suggesting earlier snowmelt, extension of growing season length and possible northward shifts in the boreal biome. This showed that the projected effects of climate change on soil temperature in snow dominated regions are complex and general assumptions of future soil temperature responses to climate change based on air temperature alone are inadequate and should be avoided in boreal regions.

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