Climate change, impacts and vulnerability in Europe ... - MemoFin.fr

Changes in the climate systemMap 2.7 Trends in consecutive wet days and consecutive dry days (1960–2012)Consecutive dry daysConsecutive wet days70N70N60N60N50N50N40N40N30N15W 0 15E 30EChange in consecutive dry days (CDD days/decade)WetterDrier– 30 – 20 – 15 – 10 – 5 0 5 10 15 20 30706050403020CDD (days)1955 1965 1975 1985 1995 2005 2015Trend: – 0.38 days per decade (– 1.83 to 1.02)Trend: – 0.37 days per decade (– 1.07 to 0.35)30N15W 0 15E 30EChange in consecutive wet days (CWD days, decade)DrierWetter– 10 – 8 – 6 – 4 – 2 0 2 4 6 8 10CWD (days)1210861955 1965 1975 1985 1995 2005 2015Trend: – 0.27 days per decade (– 0.50 to – 0.03)Trend: 0.10 days per decade (– 0.03 to 0.26)Note:High confidence in a long-term trend is shown by a black dot (if the 5th to 95th percentile slopes are of the same sign).Boxes which have a thick outline contain at least three stations. Area averaged annual time series of percentage changes andtrend lines are shown below each map for one area in northern Europe (blue line, 5.6 to 16.9 °E and 56.2 to 66.2 °N) andone in south-western Europe (red line, 350.6 to 1.9 °E and 36.2 to 43.7 °N).Source: HadEX dataset, updated with data from the ECA&D dataset.ProjectionsModel-based projections for the 21st century showa reduction in the contribution of low rainfall daysto total annual precipitation, and an increase in thecontribution of high rainfall days in most parts ofEurope, with the exception of the Iberian Peninsulaand Mediterranean regions (Boberg et al., 2009). Therecurrence time of intense precipitation is reducedfrom 20 years in the 1961–1990 periods to 6–10 yearsin the 2071–2100 period over northern and easterncentral Europe in summer (Map 2.8 left) and to2–4 years in Scandinavia in winter (Map 2.8 right)(Haugen and Iversen, 2008; Nikulin et al., 2011;Seneviratne et al., 2012).Extreme precipitation events are likely to becomemore frequent in Europe (Solomon et al., 2007).Changes in extreme precipitation depend on theregion, with a high confidence of increased extremeprecipitation in northern, Atlantic (all seasons) andcentral Europe (except in summer) (Seneviratneet al., 2012). Future projections are inconsistentin southern Europe (all seasons) (Sillman andRoeckner, 2008; Boberg et al., 2009; Seneviratneet al., 2012). The number of consecutive dry daysis projected to increase significantly in southernand central Europe, in particular in summer, and todecrease in northern Europe, in particular in winter(IPCC, 2012, figure 3.10).Climate change, impacts and vulnerability in Europe 201269