The C20C+ Detection and Attribution Project

Thursday, 17 December 2015
Poster Hall (Moscone South)
Dáithí A Stone1, Oliver Marc Angélil1, Shreyas Cholia1, Nikolaos Christidis2, Andrea Jennifer Dittus3, Christopher Kenneth Folland4, Andrew King3, James L Kinter5, Hari Krishnan1, Seung-Ki Min6, Hideo Shiogama7, Michael F Wehner1 and Piotr Wolski8, (1)Lawrence Berkeley National Laboratory, Berkeley, CA, United States, (2)Met Office Hadley center for Climate Change, Exeter, EX1, United Kingdom, (3)University of Melbourne, Parkville, VIC, Australia, (4)Met Office Hadley center for Climate Change, Exeter, United Kingdom, (5)George Mason University Fairfax, Fairfax, VA, United States, (6)POSTECH, Pohang, South Korea, (7)NIES National Institute for Environmental Studies, Tsukuba, Japan, (8)University of Cape Town, Cape Town, South Africa
Over the past decade there has been a remarkable growth in interest concerning the effects of anthropogenic emissions on extreme weather. However, research has been constrained by the lack of a public climate-model-based data product optimised for investigation of extreme weather in the context of climate change, relying instead on products designed for other purposes or on bespoke simulations designed for the particular study and not generally applicable to other extremes. The international Climate of the 20th Century Plus (C20C+) Detection and Attribution Project is filling this gap by producing the first large ensemble, multi-model, multi-year, and multi-scenario historical climate data product, specifically designed for resolving variations in the occurrence and characteristics of extreme weather from year to year and their differences from what might have been in the absence of anthropogenic emissions. Updates on project status and tens of terabytes of simulation output are available at http://portal.nersc.gov/c20c.

Here we describe the experimental design of the first phase of the project, conducted with six atmospheric climate models, and discuss its various strengths and weaknesses with respect to various types of extreme weather. We also present analyses of the relative importance of climate model, estimate of anthropogenic ocean warming, spatial and temporal scale, and aspects of experimental design on estimates of how much emissions have affected extreme weather.