Feb 8, 2016

Understanding climate change projections for precipitation over western Europe with a weather typing approach

Santos, João A., Belo‐Pereira, Margarida, Fraga, Helder, Pinto, Joaquim G.
Journal of Geophysical Research: Atmospheres
  • States that precipitation over western Europe (WE) is projected to increase (decrease) roughly northward (equatorward) of 50°N during the 21st century
  • States these changes are generally attributed to alterations in the regional large-scale circulation, e.g., jet stream, cyclone activity, and blocking frequencies
  • Uses a novel weather typing within the sector (30°W–10°E, 25–70°N) for a more comprehensive dynamical interpretation of precipitation changes
  • Identifies eight weather types: S1, S2, S3 (summertime types), W1, W2, W3 (wintertime types), B1, and B2 (blocking-like types)—their distinctive dynamical characteristics allow identifying the main large-scale precipitation-driving mechanisms
  • Identifies an overestimation of weather type frequencies associated with zonal airflow
  • Finds the frequencies of the three driest types (S1, B2, and W3) are projected to increase (mainly S1, +4%) in detriment of the rainiest types, particularly W1 (−3%)