Identifying regional heatwaves, droughts, floods

This research paper introduces a data-driven framework for identifying and mapping localized hotspots and trends for single and compound hydroclimatic hazards, such as heatwaves, droughts, and floods, using locally available data.

• The authors developed a streamlined framework to select optimal environmental indicators for detecting extreme events and analyzing trends in heatwaves, meteorological and hydrological droughts, floods, and compound occurrences. The framework utilizes temperature, precipitation, river discharge, and derived climate indices to analyze hazard intensity, frequency, duration, co-occurrence, and dependence.
• The framework employs specific indices—including the Standardized Precipitation Index, Standardized Precipitation and Evapotranspiration Index (SPEI), Standardized Streamflow Index, heatwave indices (HWIS and HWIE), and the Daily Flood Index (DFI)—with performance validated via receiver operating characteristics (ROC), area under curve (AUC), and accuracy. Compound hazard dependence is measured using a Likelihood Multiplication Factor (LMF).
• Testing the framework in Sweden with daily data from 1922–2021 identified HWIS, SPEI12, and DFI as suitable indices (AUC > 0.83). The results showed increasing occurrences of heatwaves and floods in large areas of Sweden, while droughts showed no significant change trend. Compound drought-heatwave and drought-flood events were found to be positively correlated (LMF > 1), primarily in northern Sweden between June and August.

APA

Stockholm Environment Institute (2024). Identifying regional heatwaves, droughts, floods. https://www.sei.org/publications/identifying-regional-heatwaves-droughts-floods/

Chicago

Stockholm Environment Institute. Identifying regional heatwaves, droughts, floods. 2024. https://www.sei.org/publications/identifying-regional-heatwaves-droughts-floods/.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=Identifying regional heatwaves, droughts, floods |date=11 September 2024 |url=https://www.sei.org/publications/identifying-regional-heatwaves-droughts-floods/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitute2024identifying, author = {{Stockholm Environment Institute}}, title = {{Identifying regional heatwaves, droughts, floods}}, institution = {Stockholm Environment Institute}, year = {2024}, month = sep, url = {https://www.sei.org/publications/identifying-regional-heatwaves-droughts-floods/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }