A blocking diagnosis method and its application in the blocking system over Europe in the Summer of 2010

Abstract

The blocking phenomenon has received considerable attention from many researchers due to its impact on weather and human life. This paper aims to provide a new blocking definition with applicability to observations. The daily National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data for the Northern Hemisphere of geopotential height at a level of 500 hPa during the summer season of 2010 was used in this study. Additionally, observations for several meteorological variables over the Northern Hemisphere, including Europe, through that period were collected and analyzed. By applying the new blocking definition over the Northern Hemisphere, three blocking events persisted over Europe for a duration of 5, 17 and 36 days. The exact total days of blocking events that persisted over Europe was 58 days in the summer of 2010. Moreover, during the blocking events in the summer of 2010 abnormal weather conditions, extremely hot, dry and increased pressure over Europe observed.