Linking increases in hourly precipitation extremes to atmospheric temperature and moisture changes
Open Access
- 16 April 2010
- journal article
- research article
- Published by IOP Publishing in Environmental Research Letters
Abstract
Relations between hourly precipitation extremes and atmospheric temperature and moisture derived for the present-day climate are studied with the aim of understanding the behavior (and the uncertainty in predictions) of hourly precipitation extremes in a changing climate. A dependency of hourly precipitation extremes on the daily mean 2 m temperature of approximately two times the Clausius-Clapeyron (CC) relation is found for temperatures above 10 degrees C. This is a robust relation obtained in four observational records across western Europe. A dependency following the CC relation can be explained by the observed increase in atmospheric (absolute) humidity with temperature, whereas the enhanced dependency (compared to the CC relation) appears to be caused by dynamical feedbacks owing to excess latent heat release in extreme showers. Integrations with the KNMI regional climate model RACMO2 at 25 km grid spacing show that changes in hourly precipitation extremes may indeed considerably exceed the prediction from the CC relation. The results suggests that increases of +70% or even more are possible by the end of this century. However, a different regional model (CLM operated at ETHZ) predicts much smaller increases; this is probably caused by a too strong sensitivity of this model to a decrease in relative humidity.Keywords
This publication has 17 references indexed in Scilit:
- The Soil Moisture–Precipitation Feedback in Simulations with Explicit and Parameterized ConvectionJournal of Climate, 2009
- The physical basis for increases in precipitation extremes in simulations of 21st-century climate changeProceedings of the National Academy of Sciences of the United States of America, 2009
- Unexpected rise in extreme precipitation caused by a shift in rain type?Nature Geoscience, 2009
- Unexpected rise in extreme precipitation caused by a shift in rain type?Nature Geoscience, 2009
- Increase in hourly precipitation extremes beyond expectations from temperature changesNature Geoscience, 2008
- Large-scale atmospheric circulation biases and changes in global climate model simulations and their importance for climate change in Central EuropeAtmospheric Chemistry and Physics, 2006
- The ERA‐40 re‐analysisQuarterly Journal of the Royal Meteorological Society, 2005
- Dynamic and thermodynamic changes in mean and extreme precipitation under changed climateGeophysical Research Letters, 2005
- The Changing Character of PrecipitationBulletin of the American Meteorological Society, 2003
- Constraints on future changes in climate and the hydrologic cycleNature, 2002