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  • 301.
    Hoyberget, Magne
    et al.
    Rennesveien 14, N-4513 Mandal, Norway..
    Ebbestad, Jan Ove R.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Uppsala University, Music and Museums, Museum of Evolution.
    Funke, Bjorn
    Univ Oslo, Nat Hist Museum, Pb 1172 Blindern, N-0318 Oslo, Norway..
    Funke, May-Liss K.
    Univ Oslo, Nat Hist Museum, Pb 1172 Blindern, N-0318 Oslo, Norway..
    Nakrem, Hans Arne
    Univ Oslo, Nat Hist Museum, Pb 1172 Blindern, N-0318 Oslo, Norway..
    The Skyberg Lagerstatte from the Mjosa area, Norway: a rare window into the late early Cambrian biodiversity of Scandinavia2023In: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 56, no 2, p. 1-28Article in journal (Refereed)
    Abstract [en]

    The Skyberg Biota is a new early Cambrian Konservat-Lagerstatte, documented from a 7.5-m-thick succession of the Skyberg Member, Ringstranda Formation, in the classical Mjosa area of Norway. It displays a high species diversity and contains: algae; sponges; brachiopods; hyoliths; bivalved arthropods; trilobites; palaeoscolecids and other vermiform organisms; weakly sclerotized fragments of unknown affinity; several tubicolous fossils; the enigmatic genus Lapworthella; and a number of additional problematica together with infrequent trace fossils consisting of burrows and faecal pellets. This novel macro-biota encloses the most diverse fossil assemblage known from the Cambrian Series 2 locally in the Mjosa area, and regionally in Baltoscandia, and currently includes around 50 species of 10 major animal groups and macro-algae. The Skyberg Biota contains taxa previously unknown from Norway, several are new to Baltoscandia and also includes a range of new species. The Skyberg biota offers a rare glimpse into the biodiversity of Baltoscandia just prior to the large faunal turnover at the late-middle Cambrian transition.

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  • 302.
    Hu, Yu-Zhi
    et al.
    Australian Natl Univ, Res Sch Earth Sci, Bldg 142 Mills Rd, Canberra, ACT 2601, Australia;Australian Natl Univ, Res Sch Phys & Engn, Bldg 60, Canberra, ACT 2601, Australia.
    Young, G. C.
    Australian Natl Univ, Res Sch Phys & Engn, Bldg 60, Canberra, ACT 2601, Australia.
    Burrow, Carole
    Queensland Museum, Geosci, 122 Gerler Rd, Hendra, Qld 4011, Australia.
    Zhu, You-an
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology. Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, Beijing 100044, Peoples R China.
    Lu, Jing
    Australian Natl Univ, Res Sch Phys & Engn, Bldg 60, Canberra, ACT 2601, Australia;Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, Beijing 100044, Peoples R China;CAS Ctr Excellence Life & Paleoenvironm, Beijing 100044, Peoples R China.
    High resolution XCT scanning reveals complex morphology of gnathal elements in an Early Devonian arthrodire2019In: Palaeoworld, ISSN 1871-174X, E-ISSN 1875-5887, Vol. 28, no 4, p. 525-534Article in journal (Refereed)
    Abstract [en]

    Arthodire placoderms, as a possible sister group of Chinese 'maxillate' placoderms plus crown gnathostomes, provide important information regarding early evolution of jaws and teeth. High-resolution computed tomography and digital dissection on a unique articulated 400 million-year-old buchanosteid arthrodire permitsa detailed description of the three types of gnathal elements in basal arthrodires for the first time, giving insights into their morphology and the organization of the associated dentition. In displaying numerous denticle rows (dental fields), the gnathal element morphology is very different from the much-reduced denticulation of higher brachythoracid arthrodires, even though the latter have been used recently to interpret origin and early evolution of teeth. Ossification centres are anterolateral on the anterior supragnathal (attached to the braincase), anteromesial on the posterior supragnathal (attached to the palatoquadrate), and in the central part of the biting portion of the infragnathal (attached to the meckelian cartilage). The latter bone shows no evidence of two ossification centres as has been interpreted for more advanced arthrodires. Denticle rows radiating from the ossification centre form dental fields in all three elements, and are more similar to the gnathal elements of phlyctaeniid and actinolepid arthrodires than to advanced brachythoracids. The new evidence gives insights into the primitive arthrodire condition for comparison with the dermal jaw bones of Chinese 'maxillate' placoderms that have been homologised with the premaxilla, maxilla, and dentary of osteichthyans. The new details will help clarify the sequence of character acquisition in the evolution of marginal jaw bones in basal gnathostome groups.

  • 303.
    Huang, Yizhang
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Estimating Response to Price Signals in Residential Electricity Consumption2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Based on a previous empirical study of the effect of a residential demand response program in Sala, Sweden, thisproject investigated the economic consequences of consumer behaviour change after a demand-based time ofuse distribution tariff was employed. The economic consequences of consumers were proven to bedisadvantageous in terms of unit electricity price. Consumers could achieve more electricity bill saving throughstabilising their electricity consumption during peak hours, and this way bring least compromising of theircomfort level.In order to estimate the price elasticity of the studies demand response program, a new method of estimationprice elasticity was proposed. With this method, the intensity of demand response of the demand responseprogram was estimated in terms of price elasticity. Regression analysis was also applied to find out the priceincentives of consumer behaviour change. And the results indicated that the rise in electricity supply chargehardly contributes to load reduction, while the demand-based tariff constituted an advantageous solution on loaddemand management. However stronger demand response still

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    Thesis_Yizhang_Huang
  • 304.
    Hybertsen, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Distribution of Sabellidites (Annelida?) in the Basal Cambrian of the Digermulen Peninsula, Arctic Norway2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Digermulen Peninsula, Arctic Norway, offers a unique section of late Ediacaran to Cambrian sediments in an almost complete succession within the Vestertana Group. The proposed annelidan fossil Sabellidites cambriensis is found here, within the Lower Breidvika Member and is believed to exist also in the underlying Manndrapselva Member of the Stáhpogieddi Formation. Three cycles are recognized from the Manndrapselva Member, the uppermost being the third cycle, and the sediment interval of interest for this study ranges from the third cycle of the Manndrapselva Member to the Lower Breidvika Member where the Ediacaran–Cambrian boundary is situated. The distribution of Sabellidites has been investigated in three different localities on the Digermulen Peninsula, and from two of these stratigraphical logs were made and the sections were documented with photographs. The logs were created over sediments from Locality 1: Bárdeluovttjohka and Locality 3: Manndrapselva in the interval of the top of the Manndrapselva Member and Lower Breidvika Member. Previous studies have shown that the stratigraphical distribution of Sabellidites is within the Lower Breidvika Member. New results presented in this study extended the temporal distribution downwards in the third cycle of the Manndrapselva Member and closer to the Ediacaran–Cambrian boundary. The boundary is indicated by the trace fossil Treptichnus pedum. A few samples, collected from the logged sections, were found below the T. pedum level, indicating late Ediacaran origin. Three samples were collected even further down, close to the base of the Manndrapselva log, but these could only loosely be identified as Sabellidites and further analysis is required on these specimens. The Sabellidites distribution range from the Digermulen Peninsula was briefly compared to other locations and a global correlation is possible. The results here indicate that Sabellidites is an excellent reference taxon for the terminal Ediacaran and early Cambrian and that the succession on the Digermulen Peninsula may be one of the most important for global correlation across the Ediacaran-Cambrian boundary.

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  • 305.
    Håkanson, Lars
    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. LUVAL.
    A review of uncertainties in empirical data for operational effect variables and abiotic variables including thresholds for predictive power and practical use.: Deliverable D2.3.2.2007Report (Other scientific)
  • 306.
    Håkanson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A revised dynamic model for suspended particulate matter (SPM) in coastal areas2006In: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 12, no 4, p. 327-364Article in journal (Refereed)
    Abstract [en]

    This paper presents a general, process-based model for suspended particulate matter (SPM) in defined coastal areas (the ecosystem scale). The model is based on ordinary differential equations and the calculation time (dt) is 1 month to reflect seasonal variations. The model has been tested using data from 17 Baltic coastal areas of different character and shown to predict mean monthly SPM-concentrations in water and Secchi depth (a measure of water clarity) very well (generally within the uncertainty bands given by the empirical data). The model is based on processes regulating inflow, outflow and internal fluxes. The separation between the surface-water layer and the deep-water layer is not done in the traditional manner from water temperature data but from sedimentological criteria (from the wave base which regulates where wind/wave-induced resuspension occurs). The model calculates the primary production of SPM (within the coastal areas), resuspension, sedimentation, mixing, mineralization and retention of SPM. The SPM-model is simple to apply in practice since all driving variables may be readily accessed from maps or regular monitoring programs. The model has also been extensively tested by means of sensitivity and uncertainty tests and the most important factor regulating model predictions of SPM-concentrations in coastal water is generally the value used for the SPM-concentration in the sea outside the given coastal area. The obligatory driving variables include four morphometric parameters (coastal area, section area, mean and maximum depth), latitude (to predict surface water and deep water temperatures, stratification and mixing), salinity, chlorophyll and the Secchi depth or SPM-concentration in the sea outside the given coastal area. Many of the structures in the model are general and could potentially be used for coastal areas other than those included in this study, e.g., for open coasts, estuaries or areas influenced by tidal variations.

  • 307.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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.
    Dagens fiskeripolitik leder till katastrof.2006Other (Other (popular scientific, debate etc.))
  • 308.
    Håkanson, Lars
    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. LUVAL.
    Djupt enfaldig plan för Östersjön. UNT-debatt, 2007-11-28.2007Other (Other (popular scientific, debate etc.))
  • 309.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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. LUVA.
    Extended worksheets for case-study areas and variables, including sampling frequency, number of sites and analyzed variables -– a general protocol including methodological aspects related to variations and uncertainties in empirical data needed to run and validate predictive models in coastal management.: Deliverable D2.3.1.2006Report (Other scientific)
  • 310.
    Håkanson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Factors and criteria to quantify coastal area sensitivity/vulnerability to eutrophication: Presentation of a sensitivity index based on morphometrical parameters2008In: International review of hydrobiology, ISSN 1434-2944, E-ISSN 1522-2632, Vol. 93, no 3, p. 372-388Article in journal (Refereed)
    Abstract [en]

    There are major differences in sensitivity or vulnerability to anthropogenic loading of nutrients (eutrophication) among different coastal areas. The aim of this work is to discuss criteria for coastal area sensitivity and to present a sensitivity index (SI). This index is based on two morphometric parameters, which can be determined from simple bathymetric maps. (1) The topographical openness (or exposure) and (2) the dynamic ratio of the coastal area. The exposure is defined by the ratio between the section area of the coast and the enclosed coastal area. The boundaries of the coastal area should not be defined in an arbitrary manner but according to the topographical bottleneck method so that the exposure attains a minimum value. The exposure regulates the theoretical water retention time, which, in turn, regulates the effects of a given nutrient loading. The dynamic ratio is defined by the ratio between the square root of the coastal area and the mean depth. The dynamic ratio influences many fundamental internal transport processes. Coastal management should focus remedial actions on critical coastal areas which are at hand if the nutrient loading is high and/or the sensitivity is high. Testing the sensitivity index using a comprehensive data set including 478 coastal areas from the Baltic Sea. There were 2 (0.4%) extremely sensitive coastal areas (SI > ; 50), 50 (10.5%) very sensitive coastal areas (10 < , SI < , 50), 121 (25.3%) sensitive coastal areas (5 < , SI < , 10), 301 (63.0%) low sensitive coastal areas (1 < , SI < , 5) and 4 (0.8%) not sensitive coastal areas (SI < , 1).

  • 311.
    Håkanson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Factors and criteria to quantify the bioproduction potential of coastal areas and presentation of a simple operational Index of Biological Value (IBV) for coastal management2009In: The Open Marine Biology Journal, E-ISSN 1874-4508, Vol. 3, p. 6-15Article in journal (Refereed)
    Abstract [en]

    There are major differences in the bioproduction potential of different coastal areas. The aim of this work is to review and discuss simple, operational criteria related to the bioproduction potential of coastal areas and to present and motivate an Index of Biological Value (IBV) for coastal management. This index is based on two key variables, which can be determined easily from bathymetric maps and data from standard monitoring programs: (1) the bottom area of the coast above the Secchi depth and (2) the topographical openness (or exposure) of the coastal area. The exposure is defined by the ratio between the section area of the coast and the enclosed coastal area. The boundaries of the coastal area should not be defined in an arbitrary manner but according to the topographical bottleneck method so that the exposure attains a minimum value. IBV is meant to be used to identify coastal areas with a high production potential so that preservation plans and remedial actions can be directed to such areas in a cost-efficient manner. Applying the index using a dataset including 478 coastal areas from the Baltic Sea, there were 5 (1%) extremely productive coastal areas (IBV > 50), 43 (9%) very productive coastal areas (25 < IBV < 50), 209 (43.7%) productive coastal areas (10 < IBV < 25), 214 (63.0%) moderately productive coastal areas (1 < IBV < 10) and 7 (1.5%) low-productive coastal areas (IBV < 1).

  • 312.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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.
    Helhetssyn krävs för fisket.2006Other (Other (popular scientific, debate etc.))
  • 313.
    Håkanson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modeling nutrient fluxes to, within and from the Kattegat to find an optimal, cost-efficient Swedish remedial strategy.2009 (ed. 200)Book (Other (popular science, discussion, etc.))
  • 314.
    Håkanson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modeling of lake ecosystems.2009In: Encyclopedia of Inland Waters, In: Linkens, G.E. (ed.), Oxford: Elsevier , 2009, p. 441-447Chapter in book (Other (popular science, discussion, etc.))
  • 315.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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. LUVA.
    Protocols and motivations for selected operational effect variables to be generally used to address problems and realisitc remedial measures for coastal eutrophication.: Deliverable 2.5.1.2006Report (Other scientific)
  • 316.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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. LUVA.
    Radioaktiva ämnen i insjöfisk – förändringar i tiden.2006In: Strålskyddsnytt, no 1, p. 26-28Article in journal (Refereed)
  • 317.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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. LUVA.
    Report on classification of coastal zones.: Deliverable D6.2.1.2006Report (Other scientific)
  • 318.
    Håkanson, Lars
    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. LUVA.
    Suspended particulate matter in lakes, rivers and marine systems.2006Book (Refereed)
  • 319.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. LUVAL.
    Åtgärder skall inte bygga på överdrifter.2008Other (Other (popular scientific, debate etc.))
  • 320.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bryhn, Andreas C
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Controlling eutrophication in the Baltic Sea and the Kattegat2011In: Eutrophication: causes, consequences and control / [ed] Ansari, A. A., Singh Gill, S., Lanza, G. R. and Rast, W., Springer , 2011, 1, p. 17-67Chapter in book (Other academic)
    Abstract [en]

    Eutrophication continues to be a major global challenge to water quality scientists. The global demand on water resources due to population increases, economic development, and emerging energy development schemes has created new environmental challenges to global sustainability. Eutrophication, causes, consequences, and control provides a current account of many important aspects of the processes of natural and accelerated eutrophication in major aquatic ecosystems around the world. The connections between accelerated eutrophication and climate change, chemical contamination of surface waters, and major environmental and ecological impacts on aquatic ecosystems are discussed. Water quality changes typical of eutrophication events in major climate zones including temperate, tropical, subtropical, and arid regions are included along with current approaches to treat and control increased eutrophication around the world. The book provides many useful new insights to address the challenges of global increases in eutrophication and the increasing threats to biodiversity and water quality.

  • 321.
    Håkanson, Lars
    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. LUVAL.
    Bryhn, Andreas C.
    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. LUVAL.
    Det finns inga genvägar till att rena Östersjön!2007Other (Other (popular scientific, debate etc.))
  • 322.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. LUVAL.
    Bryhn, Andreas C.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. LUVAL.
    Water pollution – methods and criteria to rank, model and remediate chemical threats to aquatic ecosystems, parts 1 and 2, 2nd edition (course compendium).2008Chapter in book (Other (popular scientific, debate etc.))
  • 323.
    Håkanson, Lars
    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. LUVAL.
    Bryhn, Andreas C.
    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. LUVAL.
    Eklund, Jenny M.
    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. LUVAL.
    Stenström-Khalili, Maria I.
    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. LUVAL.
    Practical tests and applications of a validated mass-balance model for phosphorus in coastal areas with a special focus on criteria for thresholds.: Manuscripts related to D.2.5.1 and D.2.5.2. submitted for publication in international journals. Delivery D2.5.32007Report (Other scientific)
  • 324.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Bryhn, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Rydberg, Lars
    Stigebrandt, Anders
    Walin, Gösta
    Karlsson, Magnus
    Malmaeus, Mikael
    Skattemiljarder kastas i Östersjön utan nytta.2006In: DN-debatt, Vol. 11 mars, p. 19Article in journal (Other (popular science, discussion, etc.))
  • 325.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Duarte, Carlos M.
    IMEDEA (CSIC-UIB), Spain.
    Data variability and uncertainty limits the capacity to identify and predict critical changes in coastal systems: A review of key concepts2008In: Ocean and Coastal Management, ISSN 0964-5691, E-ISSN 1873-524X, Vol. 51, no 10, p. 671-688Article in journal (Refereed)
    Abstract [en]

    How do inherent variations and uncertainties in empirical data constrain approaches to predictions and possibilities to identify critical thresholds and points of no return? This work addresses this question in discussing and reviewing key concepts and methods for coastal ecology and management. The main focus is not on the mechanisms regulating the concentration of a given variable but on patterns in variations in concentrations for many standard variables in entire lagoons, bays, estuaries or fjords (i.e., on variations at the ecosystem scale). We address and review problems related to: (1) The balance between the changes in predictive power and the accumulated uncertainty as models grow in size and include an increasing number of x-variables. (2) An approach to reduce uncertainties in empirical data. (3) Methods to maximize the predictive power of regression models by transformations of model variables and by creating time and area compatible model variables. (4) Patterns in variations within and among coastal systems of standard water variables. (5) Based on the results of the review, we also discuss the concept “Optimal Model Scale” (OMS) and an algorithm to calculate OMS, which accounts for key factors related to the predictive power at different time scales (daily to yearly prediction) and to uncertainties in predictions in relation to access to empirical data and the work (sampling effort) needed to achieve predictive power at different time scales.

  • 326.
    Håkanson, Lars
    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. LUVA.
    Eckhell, Jan
    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. LUVA.
    Suspended particulate matter (SPM) in the Baltic – New empirical data and models.2005In: Ecol. Modelling, Vol. 189, p. 130-150Article in journal (Refereed)
  • 327.
    Håkanson, Lars
    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. LUVAL.
    Eklund, Jenny M.
    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. LUVAL.
    A validated mass-balance model for phosphorus in coastal areas with a special focus on criteria for thresholds.: Delivery D2.5.22007Report (Other scientific)
  • 328.
    Håkanson, Lars
    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. LUVA.
    Gyllenhammar, Andreas
    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. LUVA.
    Setting fish quotas based on holistic ecosystem modelling including environmental factors and foodweb interactions – a new approach.2005In: Aquatic Ecology, Vol. 39, p. 325-352Article in journal (Refereed)
  • 329.
    Håkanson, Lars
    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. LUVAL.
    Lindgren, Dan
    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. LUVAL.
    A protocol (computer codes, equations and motivations) for a general operational foodweb-model for coastal areas which can be run by readily accessible driving variables from maps and monitoring programs incorporating the eutrophication model discussed in WP5. Manuscript related to D.2.7.1. to be submitted for publication in international journal.: Deliverables D2.7.1. and D.2.7.22007Report (Other scientific)
  • 330.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Lindgren, Dan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    On regime shifts and budgets for nutrients in the open Baltic Proper: evaluations based on extensive data between 1974 and 20052008In: Journal of Coastal Research, ISSN 0749-0208, E-ISSN 1551-5036, Vol. 24, no 4C, p. 246-260Article in journal (Refereed)
    Abstract [en]

    Empirical data ultimately form the basis for most environmental studies. This work uses extensive data sets from the Baltic Proper on total phosphorus, total nitrogen, chlorophyll, temperature, and salinity. We present trend analyses to see whether there have been any changes in these variables between 1990 and 2005 (and between 1974 and 2005 for chlorophyll). To put these results into a wider context, we have used data from more than 500 systems throughout the world. Selected results: The total phosphorus and total nitrogen values in the Baltic Proper are fairly stable between 1990 and 2005. There are no major changes in surface-water temperatures or salinities this period. Chlorophyll shows a slowly decreasing trend in the surface-water layer since 1974. Compared to the situation in many other marine areas, the eutrophication in the Baltic Proper is moderate. The total river inflow of total phosphorus to the Baltic Proper is 30 to 40 kt/y, about 14 kt/y of total phosphorus come from the Kattegat and about 160 kt/y from land uplift. The inflow of total nitrogen to the Baltic Proper from the Kattegat is about 120 kt/y, and about 480 kt total nitrogen per year come from land uplift. Denitrification is about 660 kt/y. The total turnover of total phosphorus in phytoplankton is about 488 kt/y. The median monthly total nitrogen/total phosphorus ratio has been higher than 7.2 (the Redfield ratio) all months since 1994, indicating that the primary production in the system is generally limited by phosphorus rather than nitrogen. If the total nitrogen/total phosphorus ratio is lower than 15, there are increasing risks of blooms of cyanobacteria, especially if the water temperature is above 15 degrees C. If the total nitrogen input to the Baltic Proper is lowered, it will mean a lowering of the total nitrogen/total phosphorus ratio and greater risks for blooming of harmful algae.

  • 331.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Lindgren, Dan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Water Transport and Water Retention in Five Connected Subbasins in the Baltic Sea: Simulations using a General Mass-Balance Modeling Approach for Salt and Substances2010In: Journal of Coastal Research, ISSN 0749-0208, E-ISSN 1551-5036, Vol. 26, no 2, p. 241-264Article in journal (Refereed)
    Abstract [en]

    This work presents monthly budgets for water and salt in the Baltic Sea and its five main sub-basins, the Baltic Proper, the Bothnian Sea, the Bothnian Bay, the Gulf of Finland and the Gulf of Riga. This process-based mass-balance modeling uses empirical data (from HELCOM) for the period 1997 to 2005. Previous models of this kind generally use water temperature data to differentiate between different water layers. This model (CoastMab) uses sedimentological criteria related to the theoretical wave base to differentiate between vertical layers. CoastMab stems from a model development in aquatic radioecology and it has previously been validated for many different substances (radionuclides, metals, nutrients, suspended particulate matter and salt) for lakes and relatively small coastal areas but not for such a large and complex system of interconnected basins as the Baltic Sea. New morphometric data for the Baltic Sea and the defined sub-basins and new hypsographic and volume curves based on digitized bathymetric data are also presented and used in this work. The aim has been to present data on the fluxes of water to the system, precipitation and the theoretical retention times for water and salt in the defined sub-basins since those values give fundamental information on how the system reacts to changes in, e.g., nutrient loading. The idea with this modeling, and the results presented in this work, is that these water fluxes, water retention rates and the algorithms to quantify vertical mixing and diffusion should be structured in such a manner that the model also can be used to quantify fluxes of nutrients and toxins. This places certain demands on the structure of the model, which may be different from physical oceanographic models, e.g., in quantifying sedimentation, resuspension, mixing and diffusion and in the requirements regarding the accessibility of the necessary driving variables.

  • 332.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. 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. LUVA.
    Malmaeus, Mikael
    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.
    Samordna åtgärderna runt Östersjön – och satsa på fosfor.2006In: Östersjön – hot och hopp, 2006, p. 101-112Chapter in book (Other (popular scientific, debate etc.))
  • 333.
    Håkanson, Louise
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Strategies for overcoming barriers to implementation of Nature-based Solutions2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 334.
    Högström, Anette
    et al.
    Tromsø universitetsmuseum.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Firsk, Åsa
    Paläontologisches Institut und Museum, Zurich University.
    Om ett dike i Siljansringen – ett historiskt klimatperspektiv2011Other (Other (popular science, discussion, etc.))
  • 335.
    Högström, Anette
    et al.
    Tromsø Universitetsmuseum.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Palacios, Teodor
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Jensen, Sören
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    New olenellid trilobites of the Digermul Peninsula, Finnmark, Northern Norway –Constraints on lower Cambrian biostratigraphy2011Conference paper (Other academic)
    Abstract [en]

    The Ediacaran to Early Ordovician succession on the Digermul Peninsula measures 1500m,mostly consisting of well-preserved siliciclastics. The Ediacaran–Cambrian transitionhere contains a rich suite of trace fossils comparable with that of the GSSP section inNewfoundland. New discoveries of Treptichnus pedum indicate that the upper part ofthe Manndraperelva Member is Cambrian. The first trilobites are found in the Uppermember of the Doulbasgaissa Formation. Previously only a few Kjerulfia lata specimenswere known, but fieldwork in the Summer of 2011 added new material of this species anda new Elliptocephala species. Both Kjerulfia lata and acritarchs place the trilobite-bearinglevel in the Holmia kjerulfia Assemblage Zone. The higher stratigraphic position of theDoulbasgaissa Formation suggested by Nielsen and Schovsbo (2011) is thus contradicted.With three olenellids and other shelly fauna, the Holmia kjerulfia Assemblage Zone in theMjösa area shows a diversity not seen on Digermul. However, the two olenellids in Digermulare unusual in Baltoscandia, where most species are known from isolated occurrences and fewor incomplete specimens. Comparison with the new material and constraints using acritarchsshould provide significant improvements on the correlation of this level in Baltoscandia.

  • 336.
    Högström, Anette
    et al.
    Tromsø Universitetsmuseum.
    Jensen, Sören
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Høyberget, Magne
    Rennesveien 14, N-4513 Mandal, Norway.
    Meinhold, Guido
    Geowissenschaftliches Zentrum der Universität Göttingen, Germany.
    McIlroy, Duncan
    Memorial University of Newfoundland.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Taylor, Wendy L.
    Department of Geological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa.
    Agic, Heda
    Department of Earth Science, University of California at Santa Barbara, Santa Barbara, USA.
    Palacios, Teodor
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Palaeopascichnus from the Ediacaran of the Digermulen Peninsula, Arctic Norway and the age of the Varanger Ice Age2018In: 5th International Palaeontological Conference, 2018, p. 292-Conference paper (Refereed)
    Abstract [en]

    Palaeopascichnids are possibly the longest-ranging macroscopic Ediacaran fossils (ca. 565-542 Ma).They are bedding plane-parallel modular fossils composed of series of closely spaced millimeter sizedcircular, sausage- or kidney- shaped units. Earlier regarded as trace fossils, they are now seen as bodyfossils: possible xenophyophoran protists or protists of uncertain affinities. The Cryogenian to lower Cambrian succession (Vestertana group) exposed on the Digermulen Peninsula starts with the glacial Smalfjorden, interglacial Nyborg and glacial Mortensnes fms, collectively known as the Varanger Ice Age.Together with the succeeding Stáhpogieddi Fm. they reflect changes from global icehouse to greenhouse conditions. The Stáhpogieddi Fm. starts with the Lillevannet Mbr. followed by the Indreelva Mbr., yielding Ediacara-type fossils. The highest member in the Stáhpogieddi Fm, the Manndrapselva Mbr, contains the Ediacaran- Cambrian boundary. Palaeopascichnus is found at three horizons within the Stáhpogieddi Fm. The youngest, within the Manndrapselva Mbr., is latest Ediacaran, based on associated trace fossils, as well as occurring below trace fossils from the Treptichnus pedum ichnozone. Palaeopascichnus is also present near the base of the Manndrapselva Mbr. The oldest occurrence is from a horizon transitional between the Lillevannet and Indreelva Mbrs. Age constraints on the Varangerian glacial deposits are poor and their relationship to Neoproterozoic glacial events is equivocal. Studies over the last several decades have placed the Smalfjorden Fm. within the globally developed Marinoan glaciation (ca. 645–635 Ma) based on the presence of cap dolostones. The Mortensnes Fm. has been aligned within the Ediacaran Gaskiers glaciation(ca. 580 Ma) on the basis of carbon isotope stratigraphy. However, alternative interpretations exist,including that of a Marinoan affinity for all of the Varanger ice age. Palaeopascichnus at the Lillevannet Mbr. to Indreelva Mbr. transition indicates that this part of the succession is younger than 565 Ma. Because the transition between the Mortensnes Fm. and the succeeding Stáhpogieddi Fm. is seemingly without major breaks in sedimentation, this is consistent with a Gaskiers, or younger age for the Mortensnes Fm. An older age (Marinoan) requires the discovery of major breaks in the sedimentary record.

  • 337.
    Högström, Anette
    et al.
    Tromsø Universitetsmuseum.
    Taylor, Wendy L.
    Department of Geological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa.
    Jensen, Sören
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Høyberget, Magne
    Rennesveien 14, N-4513 Mandal, Norway.
    Meinhold, Guido
    Geowissenschaftliches Zentrum der Universität Göttingen, Germany.
    Palacios, Teodor
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Novis, Linn
    Tromsø Universitetsmuseum.
    Ou, Zhiji
    Tromsø Universitetsmuseum.
    Exploring the Ediacaran Biota of the Digermulen Peninsula, Northern Norway2015In: Geological Society of America Abstracts with Programs, vol 47, no 7., 2015, Vol. 47Conference paper (Other academic)
    Abstract [en]

    The Digermulen Peninsula in northern Norway is the only locality that has yielded Ediacara-type fossils inScandinavia. The Peninsula exhibits an Ediacaran to Lower Ordovician succession consisting of roughly 3000 mof siliciclastic deposits formed in a foreland basin marginal to Baltica. In 2011 a restudy of the Ediacaran deposits(1000 m thick) was launched resulting in new finds that promise to establish the Digermulen Peninsula as asignificant new Ediacaran biota locality. First described in the 1990´s the assemblage is dominated by medusoidtypefossils, such as Cyclomedusa, Ediacaria?, Beltanella and Nimbia? now possibly reinterpreted astaphomorphs of the broadly defined Aspidella as exemplified by the Fermeuse assemblage in Newfoundland.Previous field seasons have produced abundant new material of discoidal forms (tentatively Aspidella), the lowestin stratigraphic proximity to the glacial Mortensnes diamictite (tentatively c. 580 Ma). Recent fieldwork during thesummer of 2015 yielded the first specimen of a multi-vaned Ediacara-type fossil from the Innerelva Member of theStáhpogiedde Formation not far from where the first discoidal fossils were found in the 90´s. Reconstructed toreach approximately 7.5 – 8 cm above the sediment surface this organism appears to have a roughly sphericalshape with three or more vanes, but more detailed study is needed. We know little of the holdfast structure but itappears to possess a generalized Aspidella-like morphology, emphasizing the variety of organisms that may havehad very similar holdfasts. In addition to Aspidella sp., well-preserved Hiemalora are present in these beds.Another important find are several specimens of Palaeopascichnus from near the base of the Innerelva Membermaking them the oldest non-stromatolite macroscopic fossils in Scandinavia. Future work for the DigermulenEarly Life Research Group will focus on extensive excavation and sampling of this important interval to increasethe understanding of the Ediacaran record on the Peninsula.

  • 338.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Coal and Oil: The Dark Monarchs of Global Energy: Understanding Supply and Extraction Patterns and their Importance for Future Production2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The formation of modern society has been dominated by coal and oil, and together these two fossil fuels account for nearly two thirds of all primary energy used by mankind.  This makes future production a key question for future social development and this thesis attempts to answer whether it is possible to rely on an assumption of ever increasing production of coal and oil. Both coal and oil are finite resources, created over long time scales by geological processes. It is thus impossible to extract more fossil fuels than geologically available. In other words, there are limits to growth imposed by nature.

    The concept of depletion and exhaustion of recoverable resources is a fundamental question for the future extraction of coal and oil. Historical experience shows that peaking is a well established phenomenon in production of various natural resources. Coal and oil are no exceptions, and historical data shows that easily exploitable resources are exhausted while more challenging deposits are left for the future.

    For oil, depletion can also be tied directly to the physical laws governing fluid flows in reservoirs. Understanding and predicting behaviour of individual fields, in particularly giant fields, are essential for understanding future production. Based on comprehensive databases with reserve and production data for hundreds of oilfields, typical patterns were found. Alternatively, depletion can manifest itself indirectly through various mechanisms. This has been studied for coal.

    Over 60% of the global crude oil production is derived from only around 330 giant oilfields, where many of them are becoming increasingly mature. The annual decline in existing oil production has been determined to be around 6% and it is unrealistic that this will be offset by new field developments, additional discoveries or unconventional oil. This implies that the peak of the oil age is here.

    For coal a similar picture emerges, where 90% of the global coal production originates from only 6 countries. Some of them, such as the USA show signs of increasing maturity and exhaustion of the recoverable amounts. However, there is a greater uncertainty about the recoverable reserves and coal production may yield a global maximum somewhere between 2030 and 2060.

    This analysis shows that the global production peaks of both oil and coal can be expected comparatively soon. This has significant consequences for the global energy supply and society, economy and environment. The results of this thesis indicate that these challenges should not be taken lightly.

    List of papers
    1. A decline rate study of Norwegian oil production
    Open this publication in new window or tab >>A decline rate study of Norwegian oil production
    2008 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 36, no 11, p. 4262-4271Article in journal (Refereed) Published
    Abstract [en]

    Norway has been a very important oil exporter for the world and an important supplier for Europe. Oil was first discovered in the North Sea in late 1960s and the rapid expansion of Norwegian oil production lead to the low oil prices in the beginning of the 1990s. In 2001 Norway reached its peak production and began to decline.

    The Norwegian oil production can be broken up into four subclasses; giant oil fields, smaller oil fields, natural gas liquids and condensate. The production of each subclass was analyzed to find typical behaviour and decline rates. The typical decline rates of giant oil fields were found to be -13% annually. The other subclasses decline equally fast or even faster, especially condensate with typical decline rates of -40% annually. The conclusion from the forecast is that Norway will have dramatically reduced export volume of oil by 2030.

    Keywords
    Future Norwegian oil production, peak oil, decline rate, field-by-field analysis, oil production policy
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-100952 (URN)10.1016/j.enpol.2008.07.039 (DOI)000261020100028 ()
    Available from: 2009-04-14 Created: 2009-04-14 Last updated: 2017-12-13Bibliographically approved
    2. The evolution of giant oil field production behaviour
    Open this publication in new window or tab >>The evolution of giant oil field production behaviour
    2009 (English)In: Natural Resources Research, ISSN 1520-7439, E-ISSN 1573-8981, Vol. 18, no 1, p. 39-56Article in journal (Refereed) Published
    Abstract [en]

    The giant oil fields of the world are only a small fraction of the total number of fields, but their importance is huge. Over 50% of the world oil production came from giants by 2005 and more than haft of the worlds ultimate reserves are found in giants. Based on this it is reasonable to assume that the future development of the giant oil fields will have a significant impact on the world oil supply.

    In order to better understand the giant fields and their future behaviour one must first understand their history. This study has used a comprehensive database on giant oil fields in order to determine their typical parameters, such as the average decline rate and life-times of giants. The evolution of giant oil field behaviour has been investigated to better understand future behaviour. One conclusion is that new technology and production methods have generally lead to high depletion rate and rapid decline. The historical trend points towards high decline rates of fields currently on plateau production.

    The peak production generally occurs before half the ultimate reserves have been produced in giant oil fields. A strong correlation between depletion-at-peak and average decline rate is also found, verifying that high depletion rate leads to rapid decline. Our result also implies that depletion analysis can be used to rule out unrealistic production expectations from a known reserve, or to connect an estimated production level to a needed reserve base.

    Keywords
    Giant oil fields, field behaviour, peak oil, depletion
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-100954 (URN)10.1007/s11053-009-9087-z (DOI)
    Available from: 2009-04-14 Created: 2009-04-14 Last updated: 2022-01-28Bibliographically approved
    3. Giant oil field decline rates and their influence on world oil production
    Open this publication in new window or tab >>Giant oil field decline rates and their influence on world oil production
    2009 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 37, no 6, p. 2262-2272Article in journal (Refereed) Published
    Abstract [en]

    The most important contributors to the world's total oil production are the giant oil fields. Using a comprehensive database of giant oil field production, the average decline rates of the world's giant oil fields are estimated. Separating subclasses was necessary, since there are large differences between land and offshore fields, as well as between non-OPEC and OPEC fields. The evolution of decline rates over past decades includes the impact of new technologies and production techniques and clearly shows that the average decline rate for individual giant fields is increasing with time. These factors have significant implications for the future, since the most important world oil production base - giant fields - will decline more rapidly in the future, according to our findings. Our conclusion is that the world faces an increasing oil supply challenge, as the decline in existing production is not only high now but will be increasing in the future.

    Keywords
    Giant oil fields, decline rates, peak oil, future oil production
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-106701 (URN)10.1016/j.enpol.2009.02.020 (DOI)000266233300030 ()
    Available from: 2009-06-27 Created: 2009-06-27 Last updated: 2017-12-13Bibliographically approved
    4. How reasonable are oil production scenarios from public agencies?
    Open this publication in new window or tab >>How reasonable are oil production scenarios from public agencies?
    2009 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 37, no 11, p. 4809-4818Article in journal (Refereed) Published
    Abstract [en]

    According to the long term scenarios of the International Energy Agency (IEA) and the U.S. Energy Information Administration (EIA), conventional oil production is expected to grow until at least 2030. EIA has published results from a resource constrained production model which ostensibly supports such a scenario. The model is here described and analyzed in detail. However, it is shown that the model, although sound in principle, has been misapplied due to a confusion of resource categories. A correction of this methodological error reveals that EIA’s scenario requires rather extreme and implausible assumptions regarding future global decline rates. This result puts into question the basis for the conclusion that global "peak oil" would not occur before 2030.

    Keywords
    Peak oil, Depletion rate, R/P ratio
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-109736 (URN)10.1016/j.enpol.2009.06.042 (DOI)000271824600063 ()
    Available from: 2009-10-23 Created: 2009-10-23 Last updated: 2022-01-28Bibliographically approved
    5. Future Danish oil and gas export
    Open this publication in new window or tab >>Future Danish oil and gas export
    2009 (English)In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 34, no 11, p. 1826-1834Article in journal (Refereed) Published
    Abstract [en]

    Denmark possesses only a small share of the exploitation rights to North Sea oil and is a minor producer when compared to Norway and the UK. However, Denmark is still an oil exporter and a very important supplier of oil for certain countries, in particular Sweden.

    A field-by-field analysis of the Danish oil and gas fields, combined with estimated production contribution from new field developments, enhanced oil recovery and undiscovered fields, provides a future production outlook. The conclusion from this analysis is that by 2030 Denmark will no longer be an oil or gas exporter at all. Our results are also in agreement with the Danish Energy Authority’s own forecast, and may be seen as an independent confirmation of their general statements.

    Decreasing Danish oil production, coupled with a rapid decline in Norway’s oil output, will force Sweden to import oil from more distant markets in the future, dramatically reducing Swedish energy security. If no new gas suppliers are introduced to the Swedish grid, then Swedish gas consumption is clearly predestined to crumble alongside declining Danish production. Future hydrocarbon production from Denmark displays a clear link to Sweden’s future energy security.

    Keywords
    Future Danish oil and gas production, Field-by-field analysis, Swedish energy security
    National Category
    Physical Sciences Environmental Analysis and Construction Information Technology Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-109738 (URN)10.1016/j.energy.2009.07.028 (DOI)000272008200009 ()
    Available from: 2009-10-23 Created: 2009-10-23 Last updated: 2022-01-28Bibliographically approved
    6. The Peak of the Oil Age: Analyzing the world oil production Reference Scenario in World Energy Outlook 2008
    Open this publication in new window or tab >>The Peak of the Oil Age: Analyzing the world oil production Reference Scenario in World Energy Outlook 2008
    Show others...
    2010 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 38, no 3, p. 1398-1414Article in journal (Refereed) Published
    Abstract [en]

    The assessment of future global oil production presented in the IEA’s World Energy Outlook 2008 (WEO 2008) is divided in to 6 fractions; four relate to crude oil, one to non-conventional oil, and the final fraction is natural-gas-liquids (NGL). Using the production parameter, depletion-rate-of-recoverable- resources, we have analyzed the four crude oil fractions and found that the 75 Mb/d of crude oil production forecast for year 2030 appears significantly overstated, and is more likely to be in the region of 55 Mb/d. Moreover, an alysis of the other fractions strongly suggests lower than expected production levels. In total, our analysis points to a world oil supply in 2030 of 75Mb/d, some 26 Mb/d lower than the IEA predicts. The connection between economic growth and energy use is fundamental in the IEA’s present modeling approach. Since our forecast sees little chance of a significant increase in global oil production, our findings suggest that the ‘‘policy makers, investors and end users’’ to whom WEO 2008 is addressed should rethink their future plans for economic growth. The fact that global oil production has very probably passed its maximum implies that we have reached the Peak of the Oil Age.

    Place, publisher, year, edition, pages
    Oxford: Elsevier Ltd, 2010
    Keywords
    Future oil supply, Peak oil, World Energy Outlook 2008
    National Category
    Physical Sciences Environmental Analysis and Construction Information Technology Other Earth and Related Environmental Sciences
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-112219 (URN)10.1016/j.enpol.2009.11.021 (DOI)000274500000019 ()
    Available from: 2010-01-11 Created: 2010-01-11 Last updated: 2022-01-28
    7. Development journey and outlook of Chinese giant oilfields
    Open this publication in new window or tab >>Development journey and outlook of Chinese giant oilfields
    2010 (English)In: Petroleum Exploration and Development, ISSN 1876-3804, Vol. 37, no 2, p. 237-249Article in journal (Refereed) Published
    Abstract [en]

    Over 70% of China’s domestic oil production is obtained from nine giant oilfields. Understanding the behaviour of these fields is essential to both domestic oil production and future Chinese oil imports. This study utilizes decline curves and depletion rate analysis to create some future production outlooks for the Chinese giants. Based on our study, we can only conclude that China’s future domestic oil production faces a significant challenge caused by maturing and declining giant fields. Evidence also indicates that the extensive use of water flooding and enhanced oil recovery methods may be masking increasing scarcity and may result in even steeper future decline rates than the ones currently being seen. Our results suggest that a considerable drop in oil production from the Chinese giants can be expected over the next decades.

    Place, publisher, year, edition, pages
    Elsevier, 2010
    Keywords
    Giant oil fields, future Chinese oil production, decline curve analysis, production modelling, oil production strategy
    National Category
    Physical Sciences Environmental Analysis and Construction Information Technology Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-126678 (URN)10.1016/S1876-3804(10)60030-4 (DOI)
    Available from: 2010-06-21 Created: 2010-06-21 Last updated: 2015-01-08Bibliographically approved
    8. Historical trends in American coal production and a possible future outlook
    Open this publication in new window or tab >>Historical trends in American coal production and a possible future outlook
    2009 (English)In: International Journal of Coal Geology, ISSN 0166-5162, E-ISSN 1872-7840, Vol. 78, no 3, p. 201-216Article in journal (Refereed) Published
    Abstract [en]

    The United States has a vast supply of coal, with almost 30% of world reserves and more than 1600 Gt (short) as remaining coal resources. The US is also the world’s second largest coal producer after China and annually produces more than twice as much coal as India, the third largest producer.

    The reserves are concentrated in a few states, giving them a major influence on future production. Historically many states have also shown a dramatic reduction in recoverable coal volumes and this has been closely investigated. Current recoverable estimates may also be too high, especially if further restrictions are imposed. The average calorific value of US coals has decreased from 29.2 MJ/kg in 1950 to 23.6 MJ/kg in 2007 as U.S. production moved to subbituminous western coals. This has also been examined in more detail.

    This study also uses established analysis methods from oil and gas production forecasting, such as Hubbert linearization and logistic curves, to create some possible future outlooks for U.S. coal production. In one case, the production stabilizes at 1400 Mt annually and remains there until the end of the century, provided that Montana dramatically increases coal output. The second case, which ignores mining restrictions, forecasts a maximum production of 2500 Mt annually by the end of the century.

    Keywords
    USA, future coal production, peak coal, coal reserves, logistic model
    National Category
    Physical Sciences Environmental Analysis and Construction Information Technology Other Earth and Related Environmental Sciences
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-100953 (URN)10.1016/j.coal.2009.03.002 (DOI)000266178900003 ()
    Available from: 2009-04-14 Created: 2009-04-14 Last updated: 2022-01-28Bibliographically approved
    9. Trends in U.S. recoverable coal supply estimates and future production outlooks
    Open this publication in new window or tab >>Trends in U.S. recoverable coal supply estimates and future production outlooks
    2010 (English)In: Natural Resources Research, ISSN 1520-7439, E-ISSN 1573-8981, Vol. 19, no 3, p. 189-208Article in journal (Refereed) Published
    Abstract [en]

    The geological coal resource of the U.S. is abundant and proved coal reserves are listed as the world’s largest. However, the reserves are unevenly distributed and located in a small number of states, giving them major influence over future production. A long history of coal mining provides detailed time series of production and reserve estimates, which can be used to identify historical trends. In reviewing the historical evolution of coal reserves, one can state that the trend here does not point towards any major increases in available recoverable reserves; rather the opposite is true due to restrictions and increased focus on environmental impacts from coal extraction. Future coal production will not be entirely determined by what is geologically available, but rather by the fraction of that amount that is practically recoverable. Consequently, the historical trend towards reduced recoverable amounts is likely to continue into the future, with even stricter regulations imposed by increased environmental concern.

    Long-term outlooks can be created in many ways, but ultimately the production must be limited by recoverable volumes since coal is a finite resource. The geologic amounts of coal are of much less importance to future production than the practically recoverable volumes. The geological coal supply might be vast, but the important question is how large the share that can be extracted under present restrictions are and how those restrictions will develop in the future. Production limitations might therefore appear much sooner than previously expected.

    Keywords
    US coal reserves, future production, peak coal
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Environmental Analysis and Construction Information Technology
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-125519 (URN)10.1007/s11053-010-9121-1 (DOI)
    Note
    This is a slightly revised and improved version of the conference paper that was presented in 2009Available from: 2010-05-20 Created: 2010-05-20 Last updated: 2017-12-12Bibliographically approved
    10. Global coal production outlooks based on a logistic model
    Open this publication in new window or tab >>Global coal production outlooks based on a logistic model
    2010 (English)In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 89, no 11, p. 3546-3558Article in journal (Refereed) Published
    Abstract [en]

    A small number of nations control the vast majority of the world’s coal reserves. The geologically available amounts of coal are vast, but geological availability is not enough to ensure future production since economics and restrictions also play an important role. Historical trends in reserve and resource assessments can provide some insight about future coal supply and provide reasonable limits for modelling. This study uses a logistic model to create long-term outlooks for global coal production. A global peak in coal production can be expected between 2020 and 2050, depending on estimates of recoverable volumes. This is also compared with other forecasts. The overall conclusion is that the global coal production could reach a maximum level much sooner than most observers expect.

    Keywords
    Future coal production, peak coal, logistic model, historical reserve and resource assessments
    National Category
    Physical Sciences Environmental Analysis and Construction Information Technology Other Earth and Related Environmental Sciences
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-127196 (URN)10.1016/j.fuel.2010.06.013 (DOI)000280604000050 ()
    Available from: 2010-07-07 Created: 2010-07-07 Last updated: 2017-12-12Bibliographically approved
    Download full text (pdf)
    FULLTEXT01
  • 339.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Coal and Peat: global resources and future supply2012In: Encyclopedia of Sustainability Science and Technology / [ed] R.A. Mayer, New York: Springer , 2012Chapter in book (Other academic)
    Abstract [en]

    Coal is the second most important fuel currently used by mankind, accounting for over 25% of the world’s primary energy supply. It provides 41% of global electricity supplies and is a vital fuel or production input for the steel, cement and chemical industries. However, coal is a fossil fuel formed from organic material by geological processes over millions of years. Hence, coal is a finite resource in terms of human time scales and its continued availability is important to the world economy.

    Peat is a related substance, but is classified somewhere between a fossil fuel and biomass. The energy sector uses peat as a fuel to generate electricity and heat. It also has applications in industrial, residential and other sectors but global consumption of peat is insignificant in comparison to coal. Peat shares many similarities with coal and is increasingly often grouped with coal for resource estimates in reports and assessments by public agencies.

    Knowing how coal and peat are created is vital to understanding how deposits are formed and what their basic properties are. Geology provides models and methodologies for describing deposits and where to find them. Exploration, drilling and surveys provide the data necessary to map deposits and assess the resources they contain. Classification schemes are also central to understanding how the terms relate to the underlying data.

    Future production of coal and peat is essential for the development of global energy supplies. It is only the produced volumes that can be used in human activities and a detailed appreciation of the production process is essential in understanding future supply developments. Factors such as economy, technology, legal and environmental constraints affect the recoverable share of the available resources, i.e. the reserves. Understanding the complexity and the greater whole of the production mechanism and the limitations that are imposed on it require a wide variety of approaches and conceptual infrastructures.

  • 340.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Depletion and decline curve analysis in crude oil production2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Oil is the black blood that runs through the veins of the modern global energy system. While being the dominant source of energy, oil has also brought wealth and power to the western world. Future supply for oil is unsure or even expected to decrease due to limitations imposed by peak oil. Energy is fundamental to all parts of society. The enormous growth and development of society in the last two-hundred years has been driven by rapid increase in the extraction of fossil fuels. In the foresee-able future, the majority of energy will still come from fossil fuels. Consequently, reliable methods for forecasting their production, especially crude oil, are crucial. Forecasting crude oil production can be done in many different ways, but in order to provide realistic outlooks, one must be mindful of the physical laws that affect extraction of hydrocarbons from a reser-voir. Decline curve analysis is a long established tool for developing future outlooks for oil production from an individual well or an entire oilfield. Depletion has a fundamental role in the extraction of finite resources and is one of the driving mechanisms for oil flows within a reservoir. Depletion rate also can be connected to decline curves. Consequently, depletion analysis is a useful tool for analysis and forecasting crude oil production. Based on comprehensive databases with reserve and production data for hundreds of oil fields, it has been possible to identify typical behaviours and properties. Using a combination of depletion and decline rate analysis gives a better tool for describing future oil production on a field-by-field level. Reliable and reasonable forecasts are essential for planning and nec-essary in order to understand likely future world oil production.

    List of papers
    1. A decline rate study of Norwegian oil production
    Open this publication in new window or tab >>A decline rate study of Norwegian oil production
    2008 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 36, no 11, p. 4262-4271Article in journal (Refereed) Published
    Abstract [en]

    Norway has been a very important oil exporter for the world and an important supplier for Europe. Oil was first discovered in the North Sea in late 1960s and the rapid expansion of Norwegian oil production lead to the low oil prices in the beginning of the 1990s. In 2001 Norway reached its peak production and began to decline.

    The Norwegian oil production can be broken up into four subclasses; giant oil fields, smaller oil fields, natural gas liquids and condensate. The production of each subclass was analyzed to find typical behaviour and decline rates. The typical decline rates of giant oil fields were found to be -13% annually. The other subclasses decline equally fast or even faster, especially condensate with typical decline rates of -40% annually. The conclusion from the forecast is that Norway will have dramatically reduced export volume of oil by 2030.

    Keywords
    Future Norwegian oil production, peak oil, decline rate, field-by-field analysis, oil production policy
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-100952 (URN)10.1016/j.enpol.2008.07.039 (DOI)000261020100028 ()
    Available from: 2009-04-14 Created: 2009-04-14 Last updated: 2017-12-13Bibliographically approved
    2. The evolution of giant oil field production behaviour
    Open this publication in new window or tab >>The evolution of giant oil field production behaviour
    2009 (English)In: Natural Resources Research, ISSN 1520-7439, E-ISSN 1573-8981, Vol. 18, no 1, p. 39-56Article in journal (Refereed) Published
    Abstract [en]

    The giant oil fields of the world are only a small fraction of the total number of fields, but their importance is huge. Over 50% of the world oil production came from giants by 2005 and more than haft of the worlds ultimate reserves are found in giants. Based on this it is reasonable to assume that the future development of the giant oil fields will have a significant impact on the world oil supply.

    In order to better understand the giant fields and their future behaviour one must first understand their history. This study has used a comprehensive database on giant oil fields in order to determine their typical parameters, such as the average decline rate and life-times of giants. The evolution of giant oil field behaviour has been investigated to better understand future behaviour. One conclusion is that new technology and production methods have generally lead to high depletion rate and rapid decline. The historical trend points towards high decline rates of fields currently on plateau production.

    The peak production generally occurs before half the ultimate reserves have been produced in giant oil fields. A strong correlation between depletion-at-peak and average decline rate is also found, verifying that high depletion rate leads to rapid decline. Our result also implies that depletion analysis can be used to rule out unrealistic production expectations from a known reserve, or to connect an estimated production level to a needed reserve base.

    Keywords
    Giant oil fields, field behaviour, peak oil, depletion
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-100954 (URN)10.1007/s11053-009-9087-z (DOI)
    Available from: 2009-04-14 Created: 2009-04-14 Last updated: 2022-01-28Bibliographically approved
    3. Giant oil field decline rates and their influence on world oil production
    Open this publication in new window or tab >>Giant oil field decline rates and their influence on world oil production
    2009 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 37, no 6, p. 2262-2272Article in journal (Refereed) Published
    Abstract [en]

    The most important contributors to the world's total oil production are the giant oil fields. Using a comprehensive database of giant oil field production, the average decline rates of the world's giant oil fields are estimated. Separating subclasses was necessary, since there are large differences between land and offshore fields, as well as between non-OPEC and OPEC fields. The evolution of decline rates over past decades includes the impact of new technologies and production techniques and clearly shows that the average decline rate for individual giant fields is increasing with time. These factors have significant implications for the future, since the most important world oil production base - giant fields - will decline more rapidly in the future, according to our findings. Our conclusion is that the world faces an increasing oil supply challenge, as the decline in existing production is not only high now but will be increasing in the future.

    Keywords
    Giant oil fields, decline rates, peak oil, future oil production
    National Category
    Physical Sciences Other Earth and Related Environmental Sciences Other Engineering and Technologies not elsewhere specified
    Research subject
    Physics with specialization in Global Energy Resources
    Identifiers
    urn:nbn:se:uu:diva-106701 (URN)10.1016/j.enpol.2009.02.020 (DOI)000266233300030 ()
    Available from: 2009-06-27 Created: 2009-06-27 Last updated: 2017-12-13Bibliographically approved
    Download full text (pdf)
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  • 341.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Global Energy Systems.
    Depletion rate analysis of fields and regions: a methodological foundation2014In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 121, no 4, p. 95-108Article in journal (Refereed)
    Abstract [en]

    This paper presents a comprehensive mathematical framework for depletion rate analysis and ties it to the physics of depletion. Theory was compared with empirical data from 1036 fields and a number of regions. Strong agreement between theory and practice was found, indicating that the framework is plausible. Both single fields and entire regions exhibit similar depletion rate patterns, showing the generality of the approach. The maximum depletion rates for fields were found to be well described by a Weibull distribution.

    Depletion rates were also found to strongly correlate with decline rates. In particular, the depletion rate at peak was shown to be useful for predicting the future decline rate. Studies of regions indicate that a depletion rate of remaining recoverable resources in the range of 2–3% is consistent with historical experience. This agrees well with earlier “peak oil” forecasts and indicates that they rest on a solid scientific ground. 

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    fulltext
  • 342.
    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?2010In: Twenty Seventh Annual International Pittsburgh Coal Conference: October 11 - 14, 2010, 2010Conference paper (Other academic)
    Abstract [en]

    Anthropogenic climate change caused by CO

    The assumptions on resource availability are in SRES based on Rogner’s assessment of world hydrocarbon resources from 1997, where it is stated that "the sheer size of the fossil resource base makes fossil sources an energy supply option for many centuries to come". Regarding the future coal production it is simply assumed to be dependent on economics, accessibility, and environmental acceptance. It is also generally assumed that coal is abundant, and will thus take a dominating part in the future energy system. Depletion, geographical location and geological parameters are not given much influence in the scenario storylines.

    This study quantifies what the coal production projection in SRES would imply in reality. SRES is riddled with future production projections that would put unreasonable expectation on just a few countries or regions. Is it reasonable to expect that China, among the world’s largest coal reserve and resource holder and producer, would increase their production by a factor of 8 over the next 90 years, as implied by certain scenarios? Can massive increases in global coal output really be justified from historical trends or will reality rule out some production outlooks as implausible?

    The fundamental assumptions regarding future fossil fuel production in SRES was investigated and compared with scientific methodology regarding reasonable future production trajectories. Historical data from the past 20 years was used to test how well the production scenarios agree with actual reality. Some of the scenarios turned out to mismatch with reality, and should be ruled out. Given the importance of coal utilization as a source of anthropogenic GHG emissions it is necessary to use realistic production trajectories that incorporate geological and physical data as well as socioeconomic parameters. SRES is underpinned by a paradigm of perpetual growth and technological optimism as well as old and outdated estimates regarding the availability of fossil energy. This has resulted in overoptimistic production outlooks.

    2 emissions is strongly and fundamentally linked to the 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. Coal, with its 26% share of world energy, is a major source of greenhouse gas emissions and commonly seen as a key contributor to anthropogenic climate change. SRES contains a wide array of different coal production outlooks, ranging from a complete coal phase-out by 2100 to a roughly tenfold increase from present world production levels. Scenarios with high levels of global warming also have high expectations on future fossil fuel production.

    Download full text (pdf)
    fulltext
  • 343.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Mapping Chinese Supply2018In: Nature Energy, E-ISSN 2058-7546, Vol. 3, no 3, p. 166-167Article in journal (Other academic)
    Abstract [en]

    Documenting the emissions and net energy of a crude supply could be essential to meeting national emission and energy security targets. Using data from hundreds of fields worldwide, a well-to-refinery study presents a high-granularity profile of China’s crude oil supply in terms of emissions and energy return on input.

    Download full text (pdf)
    fulltext
  • 344.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Global Energy Systems.
    Movement for the Emancipation of the Niger Delta (MEND)2011Other (Other (popular science, discussion, etc.))
    Download full text (pdf)
    MEND
  • 345.
    Höök, Mikael
    et al.
    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.
    A decline rate study of Norwegian oil production2008In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 36, no 11, p. 4262-4271Article in journal (Refereed)
    Abstract [en]

    Norway has been a very important oil exporter for the world and an important supplier for Europe. Oil was first discovered in the North Sea in late 1960s and the rapid expansion of Norwegian oil production lead to the low oil prices in the beginning of the 1990s. In 2001 Norway reached its peak production and began to decline.

    The Norwegian oil production can be broken up into four subclasses; giant oil fields, smaller oil fields, natural gas liquids and condensate. The production of each subclass was analyzed to find typical behaviour and decline rates. The typical decline rates of giant oil fields were found to be -13% annually. The other subclasses decline equally fast or even faster, especially condensate with typical decline rates of -40% annually. The conclusion from the forecast is that Norway will have dramatically reduced export volume of oil by 2030.

    Download full text (pdf)
    fulltext
  • 346.
    Höök, Mikael
    et al.
    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.
    Historical trends in American coal production and a possible future outlook2009In: International Journal of Coal Geology, ISSN 0166-5162, E-ISSN 1872-7840, Vol. 78, no 3, p. 201-216Article in journal (Refereed)
    Abstract [en]

    The United States has a vast supply of coal, with almost 30% of world reserves and more than 1600 Gt (short) as remaining coal resources. The US is also the world’s second largest coal producer after China and annually produces more than twice as much coal as India, the third largest producer.

    The reserves are concentrated in a few states, giving them a major influence on future production. Historically many states have also shown a dramatic reduction in recoverable coal volumes and this has been closely investigated. Current recoverable estimates may also be too high, especially if further restrictions are imposed. The average calorific value of US coals has decreased from 29.2 MJ/kg in 1950 to 23.6 MJ/kg in 2007 as U.S. production moved to subbituminous western coals. This has also been examined in more detail.

    This study also uses established analysis methods from oil and gas production forecasting, such as Hubbert linearization and logistic curves, to create some possible future outlooks for U.S. coal production. In one case, the production stabilizes at 1400 Mt annually and remains there until the end of the century, provided that Montana dramatically increases coal output. The second case, which ignores mining restrictions, forecasts a maximum production of 2500 Mt annually by the end of the century.

  • 347.
    Höök, Mikael
    et al.
    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.
    Trends in U.S. recoverable coal supply estimates and future production outlooks2009In: Twenty Sixth Annual International Pittsburgh Coal Conference: September 20-23, 2009, Pittsburgh: University of Pittsburgh , 2009Conference paper (Refereed)
    Abstract [en]

    The geological coal resource of the U.S. is abundant and proved coal reserves are listed as the world’s largest. However, the reserves are unevenly distributed and located in a small number of states, giving them major influence over future production. A long history of coal mining provides detailed time series of production and reserve estimates, which can be used to identify historical trends. Compilation of data from United States Geological Survey, Energy Information Administration, U.S. Bureau of Mines and others reveal how the recoverable volumes have been decreased since before the 1950s. The exact cause of this reduction is probably a multitude of factors, including depletion, changes in economic conditions, land-use restrictions, environmental protection and social acceptance.

    In reviewing the historical evolution of coal reserves, one can state that the trend here does not point towards any major increases in available recoverable reserves; rather the opposite is true due to restrictions and increased focus on environmental impacts from coal extraction. The development of new even stricter regulations and environmental laws is also a reasonable assumption and this will further limit the amount of recoverable coal. Future coal production will not be entirely determined by what is geologically available, but rather by the fraction of that amount that is practically recoverable. Consequently, the historical trend towards reduced recoverable amounts is likely to continue into the future, with even stricter regulations imposed by increased environmental concern.

    Long-term outlooks can be created in many ways, but ultimately the production must be limited by recoverable volumes since coal is a finite resource. Various models, such as the logistic, Hubbert or Gompertz curves, can be used to provide reasonable long-term outlooks for future production. However, such long-term life-cycle projections should not be used as a substitute for meticulous economic studies to forecast perturbations in coal production over the next few years or decades. Based on a logistic model, using the recoverable reserves as an estimate of what is realistically available for production, results in a coal output of around 1400 Mt by 2030 through the rest of the century.

    The geologic amounts of coal are of much less importance to future production than the practically recoverable volumes. The geological coal supply might be vast, but the important question is how large the share that can be extracted under present restrictions are and how those restrictions will develop in the future. Production limitations might therefore appear much sooner than previously expected.

    Download full text (pdf)
    fulltext
  • 348.
    Höök, Mikael
    et al.
    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.
    Trends in U.S. recoverable coal supply estimates and future production outlooks2010In: Natural Resources Research, ISSN 1520-7439, E-ISSN 1573-8981, Vol. 19, no 3, p. 189-208Article in journal (Refereed)
    Abstract [en]

    The geological coal resource of the U.S. is abundant and proved coal reserves are listed as the world’s largest. However, the reserves are unevenly distributed and located in a small number of states, giving them major influence over future production. A long history of coal mining provides detailed time series of production and reserve estimates, which can be used to identify historical trends. In reviewing the historical evolution of coal reserves, one can state that the trend here does not point towards any major increases in available recoverable reserves; rather the opposite is true due to restrictions and increased focus on environmental impacts from coal extraction. Future coal production will not be entirely determined by what is geologically available, but rather by the fraction of that amount that is practically recoverable. Consequently, the historical trend towards reduced recoverable amounts is likely to continue into the future, with even stricter regulations imposed by increased environmental concern.

    Long-term outlooks can be created in many ways, but ultimately the production must be limited by recoverable volumes since coal is a finite resource. The geologic amounts of coal are of much less importance to future production than the practically recoverable volumes. The geological coal supply might be vast, but the important question is how large the share that can be extracted under present restrictions are and how those restrictions will develop in the future. Production limitations might therefore appear much sooner than previously expected.

    Download full text (pdf)
    fulltext
  • 349.
    Höök, Mikael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Bardi, Ugo
    University of Firenze.
    Feng, Lianyong
    China University of Petroleum - Beijing.
    Pang, Xiongqi
    China University of Petroleum - Beijing.
    Development of oil formation theories and their importance for peak oil2010In: Marine and Petroleum Geology, ISSN 0264-8172, E-ISSN 1873-4073, Vol. 27, no 9, p. 1995-2004Article in journal (Refereed)
    Abstract [en]

    This paper reviews the historical development of both biogenic and non-biogenic petroleum formation. It also examines the recent claim that the so-called “abiotic” oil formation theory undermines the concept of “peak oil,” i.e. the notion that world oil production is destined to reach a maximum that will be followed by an irreversible decline. We show that peak oil is first and foremost a matter of production flows. Consequently, the mechanism of oil formation does not strongly affect depletion. We would need to revise the theory beyond peak oil only for the extreme — and unlikely — hypothesis of abiotic petroleum formation.

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  • 350.
    Höök, Mikael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Global Energy Systems.
    Dean, Fantazzini
    Moscow State University.
    André, Angelantoni
    Post Peak Living.
    Simon, Snowden
    University of Liverpool.
    Coal-to-Liquids: viability as a peak oil mitigation strategy2012In: Twenty Ninth Annual International Pittsburgh Coal Conference, 2012Conference paper (Refereed)
    Abstract [en]

    Converting coal to a liquid, commonly known as coal-to-liquids (CTL), can supply liquid fuels and has been successfully used in several countries, particularly in South Africa. However, it has not become a major contributor to the global oil supply. Increasing awareness of the scarcity of oil and rising oil prices has increased the interest in coal liquefaction. This paper surveys CTL technology, economics and environmental performance. Understanding the fundamental aspects of coal liquefaction technologies is vital for planning and policy-making since future CTL production will be integrated in a much larger global energy and liquid fuel production system.

    The economic analysis shows that many CTL studies assume conditions that are optimistic at best. In addition, the strong risk for a CTL plant to become a financial black hole is highlighted. This helps to explain why China has recently slowed down the development of its CTL program.

    The technical analysis investigates the coal consumption of CTL. Generally, a yield of between 1–2 barrels/ton coal can be achieved while the technical limit seems to be 3 barrels/ton coal. This puts a strict limit on future CTL capacity imposed by future coal production, regardless of other factors such as economic viability, emissions or environmental concern. For example, assuming that 10% of world coal production can be diverted to CTL, the contribution to the liquid fuel supply will be limited to only a few million barrels per day (Mb/d). This prevents CTL from becoming a viable mitigation plan for liquid fuel shortage on a global scale.

    However, it is still possible for individual nations to derive a significant share of their fuel supply from CTL but those nations must also have access to equally significant coal production capacity. It is unrealistic to claim that CTL provides a feasible solution to liquid fuels shortages created by peak oil. At best, it can be only a minor contributor and must be combined with other strategies to ensure future liquid fuel supply.

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