Method for the quantification of impact-relevant (multi-)hazard durations
Author(s): Kelley De Polt, Philip J Ward, Marleen de Ruiter, Ekaterina Bogdanovich, Markus Reichstein, Dorothea Frank and René Orth
Organisation(s)/Authors: Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany; Institute for Environmental Studies, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
Description:
This method pinpoints impact-relevant durations for single and multi-hazards by De Polt et al. 2023. Utilisation of the methodology can inform and suggest the choice of time scales at which hazard characteristics (e.g., hourly high temperature, daily mean soil moisture) should be aggregated to ensure it is most representative to the impact or response metric of interest (e.g., monthly time scales vs daily or seasonal time scales), enabling more comparable and informed research and impact assessments.
Abstract excerpt for application of method within case analysis of societal responses to heatwaves in Germany:
"Heatwaves are weather hazards that can influence societal and natural systems. Recently, heatwaves have increased in frequency, duration, and intensity, and this trend is projected to continue as a consequence of climate change. The study of heatwaves is hampered by the lack of a common definition, which limits comparability between studies. This applies in particular to the considered time scale for utilised metrics. Here, we study which durations of heatwaves are most impact-relevant for various types of impacts. For this purpose, we analyse societal metrics related to health (heat-related hospitalisations, mortality) and public attention (Google trends, news articles) in Germany. Country-averaged temperatures are calculated for the period of 2010–2019 and the warmest periods of all time scales between 1 and 90 days are selected. Then, we assess and compare the societal response during those periods to identify the heatwave durations with the most pronounced impacts. Note that these durations are based on average temperatures across the given time frame while individual days may be less warm. The results differ slightly between the considered societal metrics but indicate overall that heatwaves induce the strongest societal response at durations between 2 weeks and 2 months for Germany. Finally, we show that heatwave duration affects the societal response independent of, and additionally to, heatwave temperatures. This finding highlights the relevance of making informed choices on the considered time scale in heatwave analyses. The approach we introduce here can be extended to other societal indices, countries, and hazard types to reveal more meaningful definitions of climate extremes to guide future research on these events." (De Polt et al., 2023; ERL)
Corresponding Author: Kelley De Polt (kdepolt@bgc-jena.mpg.de)
Technical Considerations:
Key Words:
hazard characteristics, impact assessment, method