Variability of weather regimes in the North Atlantic‐European area: past and future

• Published in: Atmospheric Science Letters
• Main Authors: Hertig, Elke, Jacobeit, Jucundus
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2014
• Subjects: North Atlantic; North Atlantic oscillation
• Online Access: http://dx.doi.org/10.1002/asl2.505; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fasl2.505; https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/asl2.505

Abstract The concept of weather regimes represents a process‐oriented method of organizing the varying states of the atmospheric circulation. We define weather regimes as preferred, or recurrent, circulation patterns. We use a suite of reanalysis products and general circulation model ( GCM ) simulations to assess the reproducibility and variability of the regimes. We find distinct variability of the regimes in observational periods as well as in future projections. Most notable is the high variability of the North Atlantic Oscillation (NAO) regime anomaly patterns in the GCM simulations which is not evident in reanalyses, and the substantial increase of variability regarding the frequency of occurrence of the Atlantic ridge regime and the NAO + regime .