Simulating storms that cause extreme rainfall accumulations has been a long-standing challenge in weather and climate modeling. Tremendous improvements have been made over recent decades due to advances in models and computational resources that nowadays allow us to explicitly simulate storm-scale dynamics within models. This results in a step-improvement in simulating heavy rainfall producing storms and allows unprecedented insights into climate change impacts on rainfall extremes. This talk will exemplify the added value of simulating extreme rainfall producing storms in kilometer-scale models compared to coarser-resolution models. It will be shown how the most important storm characteristics that are associated with flooding (e.g., rainfall rates, storm movement speed, and storm spatial extent) are realistically simulated in kilometer-scale models. For the first time, these models allow us to assess how storm characteristics are changing in future climates. Our current understanding of climate change impacts on precipitation extremes will be summarized and remaining challenges and opportunities will be highlighted.
Contact: Andreas F. Prein