Summary/Abstract
Extreme weather events, such as tropical cyclones, often trigger population displacement. The frequency and intensity of tropical cyclones are affected by anthropogenic climate change. However, the effect of historical climate change on displacement risk has so far not been quantified.
In this peer-reviewed study, published in Natural Hazards and Earth System Sciences, the authors show how displacement can be partially attributed to climate change using the example of the 2019 Tropical Cyclone Idai in Mozambique. The authors estimate the population exposed to high water levels following Idai’s landfall using a combination of a 2D hydrodynamical storm surge model and a flood depth estimation algorithm to determine inland flood depths from remote sensing images, factual (climate change) and counterfactual (no climate change) mean sea level, and maximum wind speed conditions. The study’s main estimates indicate that climate change has increased displacement risk from this event by approximately 12,600–14,900 additional displaced persons, corresponding to about 2.7 % to 3.2 % of the observed displacements. The study further finds that the isolated effect of wind speed intensification is double that of sea level rise.