Prof. Philip D. Jones

CRU, University of East Anglia

10 am, 3 June, 2015

Room 319, Building 40, IAP

This talk expands on the first addressing a number of issues only discussed briefly. These include: Absolute Temperatures, Comparisons with Reanalyses, National Averages and European Extremes. Most users of the gridded temperature products are happy to use temperatures expressed as anomalies, but some such as climate modellers would like absolute temperatures. Reanalyses have dramatically improved in the recent decade, so spatial comparisons can show where there can be issues with absolute and anomaly temperatures. Despite papers for the gridded products being highly cited, more citations are evident for the CRU TS 3.22 dataset (which is at 0.5° by 0.5° latitude/longitude), which is spatially infilled, as opposed to CRUTEM4. Here we show national averages computed for some of the 198 recognized countries of the UN from both CRU TS 3.22 and CRUTEM4. Both these datasets are at the monthly scale, but it is possible to look at changes in extremes at this timescale, but only for the CRUTEM4v dataset. The final part of the talk looks at daily data across Europe for trends in a number of temperature metrics and compares results with ERA-Interim.