Extreme events and their simulation in climate models

Extreme climate and weather events have pronounced impacts on the natural environment and human society, and they are receiving increasing attention in connection with the ongoing changes in the climate system.

We evaluate outputs of climate models by comparing them to the observed data/reanalyses, study spatial and temporal characteristics of extremes, and examine the role of atmospheric circulation and other meteorological factors in their initiation and development. For precipitation extremes, we develop extreme value models to improve estimates of growth curves and design values for high return levels, with focus on different processes leading to heavy precipitation.

We analyse past changes in heat waves’ and cold spells’ characteristics and evaluate climate change scenarios of extremes and associated uncertainties. We also study compound extremes, e.g. relationships between heat waves and droughts or high-impact winter weather.