CASCADE team members Chris Paciorek and Michael Wehner prepared this figure describing changes in extreme temperature and precipitation for review articles in the Bulletin of the American Meteorological Society as source material for the 3rd US National Climate Assessment.
The figure set shows change over 1950-2007 in estimated 20-year return value (oC) for (a) upper tail of daily maximum temperature, max(Tmax) (b) lower tail of daily maximum temperature, min(Tmax) (c) upper tail of daily minimum temperature, max(Tmin) and (d) lower tail of daily minimum temperature, min(Tmin). Results are based on fitting extreme value statistical models with a linear trend in the location parameter to exceedances of a location-specific threshold (greater than the 99th percentile for upper tail and less than the 1th percentile for lower tail). Circles indicate z-score for the estimated change (estimate divided by its standard error), with absolute z-scores exceeding 1, 2, and 3 indicated by open circles of increasing size.
Source: Peterson, et al. (2013) Monitoring and Understanding Changes in Heatwaves, Coldwaves, Floods and Droughts in the United States: State of Knowledge, Bulletin of the American Meteorological Society June 2013, 821-834, DOI: 10.1175/BAMS-D-12-00066.1, Supplement DOI: 10.1175/BAMS-D-12-00066.2