Logo: to the web site of Uppsala University

uu.sePublications from Uppsala University
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Earthquake disaster fatality data: Temporally stable power-law behavior and effects of underreporting
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics. (Seismologi)ORCID iD: 0000-0002-6337-7839
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.ORCID iD: 0000-0001-7251-0059
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.ORCID iD: 0000-0002-2511-187X
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.ORCID iD: 0000-0002-0789-5949
(English)In: Seismological Research Letters, ISSN 0895-0695, E-ISSN 1938-2057Article in journal (Refereed) Submitted
Abstract [en]

We investigate changes in the global reported fatalities from earthquake disasters in theleading global disaster database EM-DAT. Drawing parallels with the Gutenberg-Richterfrequency-magnitude analysis, in terms of disaster frequency versus the number of casual-ties, we see a significant overlap of the curves and improving levels of completeness oversix 20-year periods. This implies a decrease in underreporting with time. We find that theapparent strong upwards trend in the number of (reported) earthquake disasters in EM-DATis caused by a gradually improved reporting primarily of events killing fewer than 10 peo-ple. An implication of our findings is that the true (reported and unreported) number ofearthquake disasters, according to the EM-DAT definition, has been surprisingly constantover, at least, the last 100 years. We also show that the average annual number of peoplekilled in earthquake disasters is relatively unaffected by spurious trends in reporting, and hasremained remarkably constant, at least since the 1960s, despite population increase.

National Category
Geophysics
Identifiers
URN: urn:nbn:se:uu:diva-517254OAI: oai:DiVA.org:uu-517254DiVA, id: diva2:1817354
Available from: 2023-12-06 Created: 2023-12-06 Last updated: 2023-12-13
In thesis
1. Bias-adjusted analysis of global natural disaster records and an assessment of seismic hazard in Sweden
Open this publication in new window or tab >>Bias-adjusted analysis of global natural disaster records and an assessment of seismic hazard in Sweden
2024 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Natural disasters pose significant challenges today and demand efficient allocation of society’s limited resources for disaster risk reduction. This relies on analysis of natural disaster records, which are prone to (reporting) biases that can affect the inferences drawn from their analysis. Data incompleteness is common in earthquake seismology, and, with a starting point in the Gutenberg-Richter law, this thesis studies the power-law behaviour between fatalities and the frequency of global natural disasters recorded by EM-DAT from 1900 to 2020. 

Analysing, first, the power-law behaviour of global earthquake frequency and magnitude reveals overlapping patterns, and apparent improved reporting completeness over the studied periods, implying any increase in recorded earthquakes is a reporting artefact. Similarly, “frequency-magnitude” analysis of earthquake disasters shows power-law behaviour and an almost-unchanged distribution of fatalities over time, which also implies improved reporting. Similar analysis of hydro-meteorological disasters in EM-DAT shows their substantially increased number with time to be a reporting artefact driven by improved reporting of low-fatality disasters. The increasing gradient of the power-law part of the frequency-magnitude graphs implies that the worst events have become less fatal on average.  

Climate-related disaster risk reduction actions have thus been very successful, resulting in a continuous decline in aggregate associated fatalities, to the extent that earthquakes have been the most fatal natural disasters over the last few decades.  Notably, while the earthquake magnitude distribution is dominated by earthquakes in high-seismicity zones, fatalities predominantly occur in low-seismicity intraplate regions. This implies that seismic hazard in Sweden, an intraplate area, may be significant, especially as earthquakes as large as M8 have occurred in its recent deglaciation phase. Hazard analysis based on data from the recently expanded Swedish seismic network clearly unveils significant hazard posed by Post-Glacial faults in the North. 

This research advances our understanding of natural disaster dynamics, emphasizing the necessity for non-conventional methodologies to analyze historical data. It offers important insights to help form effective disaster risk reduction strategies, particularly in the context of seismic hazard assessment for specific regions like Sweden.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2024. p. 73
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 2347
Keywords
Power-law, Natural-disasters, Seismic-hazard assessment.
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-517257 (URN)978-91-513-1985-8 (ISBN)
Public defence
2024-03-01, Hambergsalen, Geocentrum, Villavägen 16, Uppsala, 13:00 (English)
Opponent
Supervisors
Available from: 2024-02-07 Created: 2023-12-06 Last updated: 2024-02-07

Open Access in DiVA

No full text in DiVA

Authority records

Roberts, RolandTryggvason, AriLund, Björn

Search in DiVA

By author/editor
Joshi, NiranjanRoberts, RolandTryggvason, AriLund, Björn
By organisation
Geophysics
In the same journal
Seismological Research Letters
Geophysics

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 104 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf