Assessment of an extended version of the Jenkinson–Collison classification on CMIP5 models over Europe

Abstract

the warmer seasons over Southeast and Southwest Europe, respectively. Our results indicate that in winter the Westerly type has significant impacts on positive anomalies of maximum and minimum temperature over most of Europe. Except in winter, the warmer temperatures are linked to Easterlies, Anticyclonic and Low Flow conditions, especially over the Mediterranean area. Furthermore, we show that changes in the frequency of weather types represent a minor contribution of the total change of European temperatures, which would be mainly driven by changes in the temperature anomalies associated with the weather types themselves.

Reductions in daily continental-scale atmospheric circulation biases between generations of global climate models: CMIP5 to CMIP6

“…More generally, regional biases in relevant circulation features have been assessed with the aid of circulation pattern or weather type classifications-automated classification schemes that group daily or sub-daily circulation fields into a small number of dominant modes of high-frequency variability (e.g. McKendry et al 1995, Schoof and Pryor 2006, Otero et al 2017, Stryhal and Huth 2018. These classifications are region-specific, identifying the main circulation patterns that control weather conditions in the region of interest.…”

Past and Projected Weather Pattern Persistence with Associated Multi-Hazards in the British Isles

“…Similarly, summer 2013 in eastern China, was the hottest ever recorded in that region, with persistent and widespread heatwaves and droughts causing severe socio-economic impacts amounting to 59 billion RMB in losses [11]. Conversely, the extremely wet and Previous evaluations for Europe and the BI show that Coupled Model Intercomparison Project Phase 5 (CMIP5) AOGCMs generally reproduce LWTs, calculated using daily sea-level pressure (SLP) fields, but there are recognized biases [53,54]. For example, CMIP5 AOGCMs are not yet able to simulate correctly the number of anticyclonic (A-type) patterns and hence blocking episodes, with the former being underestimated in northern Europe and the BI, but overestimated in southern Europe [53,54,70].…”

“…Conversely, the extremely wet and Previous evaluations for Europe and the BI show that Coupled Model Intercomparison Project Phase 5 (CMIP5) AOGCMs generally reproduce LWTs, calculated using daily sea-level pressure (SLP) fields, but there are recognized biases [53,54]. For example, CMIP5 AOGCMs are not yet able to simulate correctly the number of anticyclonic (A-type) patterns and hence blocking episodes, with the former being underestimated in northern Europe and the BI, but overestimated in southern Europe [53,54,70]. Other biases are found for cyclonic (C-type) and westerly (W-type) occurrences, with both being overestimated across Europe [54].…”

“…For example, CMIP5 AOGCMs are not yet able to simulate correctly the number of anticyclonic (A-type) patterns and hence blocking episodes, with the former being underestimated in northern Europe and the BI, but overestimated in southern Europe [53,54,70]. Other biases are found for cyclonic (C-type) and westerly (W-type) occurrences, with both being overestimated across Europe [54]. These studies also examined future changes in frequency of LWTs and blocking episodes by comparing historical conditions with Representative Concentration Pathway (RCP) 8.5, to determine how such changes might affect European temperatures.…”

“…These studies also examined future changes in frequency of LWTs and blocking episodes by comparing historical conditions with Representative Concentration Pathway (RCP) 8.5, to determine how such changes might affect European temperatures. The A-type is projected to increase significantly over the BI during all seasons except for winter December-January-February (DJF), the C-type to decrease in all seasons, and the W-type to increase except in summer June-July-August (JJA) by the end of the century [54]. Overall, blocking episodes are projected to decrease for the BI in DJF and JJA by 2061-2090 (RCP8.5) [70].…”