The costs of extreme weather events in RCP-SSP future pathways – From individual damages to effects on national GDP

Organizers: Katja Frieler (PIK), Christian Otto (PIK), Matthias Kalkuhl (Mercator Research Institute)


In the last decades, weather related extreme events have on average caused a global annual economic damage of 100 billion US$ (MunichRe, NatCatServiceTool). Though already large, temporal and spatial average numbers hide the potentially disruptive nature that actually emerges from the large spatial and temporal fluctuation of those events. So far, comprehensive temporally and spatially explicit projections of aggregated damages were hampered by the diversity of events (e.g. tropical cyclones, agricultural damages induced by droughts or heat waves, river or coastal flooding, and wildfires) that wereare individually addressed in different research disciplines. Recent interdisciplinary research efforts - fostered by large-scale model comparison exercises such as the Intersectoral Impact Model Intercomparison Project (ISIMIP) - have opened up the possibility to generate individual potential realizations of national time series of annual damages aggregated across the main event categories. These projections could enable further projections of macroeconomic effects leading to RCP-specific deviations from SSP-based GDP projections that currently do not account for climate change impacts. This session is dedicated to a synthesis of i) the current status of projections of direct damages aggregated across different types of weather related extreme events and ii) macroeconomic modelling approaches that allow for the
translation of direct damages related to individual RCPs into deviations from national SSPbased GDP time series resolving potential non-linear effects and recovery dynamics associated with year-to-year fluctuations of damages.