Paper No. JAWRA-10-0049-P of the Journal of the American Water Resources Association (JAWRA). This article is a U.S. Government work and is in the public domain in the USA. Discussions are open until six months from print publication.
Climate Change, Atmospheric Rivers, and Floods in California – A Multimodel Analysis of Storm Frequency and Magnitude Changes1
Article first published online: 1 JUN 2011
© 2011 American Water Resources Association
JAWRA Journal of the American Water Resources Association
Volume 47, Issue 3, pages 514–523, June 2011
How to Cite
Dettinger, M. (2011), Climate Change, Atmospheric Rivers, and Floods in California – A Multimodel Analysis of Storm Frequency and Magnitude Changes. JAWRA Journal of the American Water Resources Association, 47: 514–523. doi: 10.1111/j.1752-1688.2011.00546.x
- Issue published online: 1 JUN 2011
- Article first published online: 1 JUN 2011
- Received April 16, 2010; accepted December 20, 2010.
- climate variability/change;
- atmospheric rivers;
Dettinger, Michael, 2011. Climate Change, Atmospheric Rivers, and Floods in California – A Multimodel Analysis of Storm Frequency and Magnitude Changes. Journal of the American Water Resources Association (JAWRA) 47(3):514-523. DOI: 10.1111/j.1752-1688.2011.00546.x
Abstract: Recent studies have documented the important role that “atmospheric rivers” (ARs) of concentrated near-surface water vapor above the Pacific Ocean play in the storms and floods in California, Oregon, and Washington. By delivering large masses of warm, moist air (sometimes directly from the Tropics), ARs establish conditions for the kinds of high snowlines and copious orographic rainfall that have caused the largest historical storms. In many California rivers, essentially all major historical floods have been associated with AR storms. As an example of the kinds of storm changes that may influence future flood frequencies, the occurrence of such storms in historical observations and in a 7-model ensemble of historical-climate and projected future climate simulations is evaluated. Under an A2 greenhouse-gas emissions scenario (with emissions accelerating throughout the 21st Century), average AR statistics do not change much in most climate models; however, extremes change notably. Years with many AR episodes increase, ARs with higher-than-historical water-vapor transport rates increase, and AR storm-temperatures increase. Furthermore, the peak season within which most ARs occur is commonly projected to lengthen, extending the flood-hazard season. All of these tendencies could increase opportunities for both more frequent and more severe floods in California under projected climate changes.