Relationships of surface air temperature anomalies over Europe to persistence of atmospheric circulation patterns conducive to heat waves

摘要

Heat waves are among natural hazards with the most severe consequences forhuman society, including pronounced mortality impacts in mid-latitudes.Recent studies have hypothesized that the enhanced persistence ofatmospheric circulation mayaffect surface climatic extremes, mainly the frequency and severity of heatwaves. In this paper we examine relationships between the persistence of theHess-Brezowsky circulation types conducive to summer heat waves and airtemperature anomalies at stations over most of the European continent. Wealso evaluate differences between temperature anomalies during late andearly stages of warm circulation types in all seasons. Results show thatmore persistent circulation patterns tend to enhance the severity of heatwaves and support more pronounced temperature anomalies. Recent sharplyrising trends in positive temperature extremes over Europe may be related tothe greater persistence of the circulation types, and if similar changestowards enhanced persistence affect other mid-latitudinal regions, analogousconsequences and implications for temperature extremes may be expected.