US CLIVAR Extremes Working Group Results, Recommendations, and Recourses

Abstract:

The topic of extreme weather and climate is very broad. One can easily list a dozen different types of atmospheric extreme phenomena. In addition, some extreme phenomena have multiple types of extremes as well as categories of extremes. The first US CLIVAR working group on extremes (EWG) chose to narrow the extreme phenomena to temperature and precipitation extremes having a time scale of a few days to a week. The primary extremes considered were short term heat waves, cold air outbreaks, and extreme precipitation not from tropical cyclones. All of these have produced multi-billion dollar losses in recent years. Even this subset of extremes is very broad, so additional focus was placed upon the large scale meteorological patterns (LSMPs) that accompany these extremes. This working group was most active from its inception in 2012 until its nominal ending in 2015. Additional work continues, including follow-on activities spawned or informed by the EWG. In this talk, the EWG activities are summarized in four areas: data for extremes, statistical analyses applicable to extremes, synoptic-dynamics of these extremes, and simulation of these extremes in climate models. The emphasis will be upon knowledge gaps and recommended further actions in these four areas. The recommendations span basic science through applications. The EWG participation included input into the US CLIVAR science plan, as one of the four research challenges there being ‘extremes’. A scientific session at this AGU meeting was a direct outgrowth of the EWG 2013 workshop. Other follow-on work includes consultation with various national and international efforts in extremes. Finally, some possible future applications of the EWG efforts, such as adequate datasets and climate model diagnostic tools, will be mentioned that may inform providers of information having direct interest to end-users.