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

Climate impacts on environmental systemsFigure 3.72.52.01.51.00.50A1B. Meehl et al. (2007)Note:Sea-level rise (m)A2. Meehl et al. (2007)Range of high-end estimates ofglobal sea-level rise publishedafter the IPCC AR4Rahmstorf et al. (2007)A1Fl. Meehl et. al (2007)Rohling et al. (2008)Vellinga et al. (2008)Grinsted et al. (2009)Pfeffer et al. (2008)Kopp et al. (2009)Vermeer and Rahmstorf (2009)Range of high-end global sea-level rise (metre percentury) estimates published after the IPCC FourthAssessment Report (AR4). AR4 results are shown forcomparison in the three left-most columns.Source: Nicholls et al., 2010.sea-level rise of 0.55 to 1.15 m. However, theyagain concluded that although the probability oflarger increases is small, it was still not possible torule out increases approaching around 2 m basedon palaeo‐climatic evidence (Rohling et al., 2008).In summary, the highest projections available inthe scientific literature should not be treated aslikely increases in 21st century sea level, but theyare useful for vulnerability tests against floodingin regions where there is a large risk aversionto flooding, or the consequences of flooding areparticularly catastrophic.Specific projections for regional seasFuture projections of the spatial pattern of sea-levelrise also remain highly uncertain. There was littleimprovement in reducing this uncertainty betweenthe IPCC Third and Fourth Assessment Report.Recent model improvements, however, may reducethis uncertainty in the future. One study producedestimates of sea-level rise around the UnitedKingdom based on results from the IPCC AR4(Lowe et al., 2009). This study estimates absolutesea-level rise (which exclude changes in land level)around the United Kingdom for the 21st centuryin the range of 12 cm (the lower bound of the Lowemission scenario) to about 76 cm (the upper boundof the High emission scenario). Larger rises couldresult from an additional ice sheet term, but thisis more uncertain. Another study estimated theplausible high-end scenario for 21st century sea-levelrise on the North Sea coast of the Netherlands in therange 40 to 105 cm (Katsman et al., 2011). Makingmulti-decadal regional projections for relativelysmall isolated and semi‐isolated basins, such asthe Mediterranean, is even more difficult thanfor the global ocean. One study made projectionsfor the Mediterranean Sea based on the output of12 global climate models for 3 emission scenarios(Marcos and Tsimplis, 2008). The results project anocean temperature-driven sea-level rise during the21st century between 3 and 61 cm over the basin,which needs to be combined with a salinity-drivensea‐level change between – 22 and + 31 cm.Climate change, impacts and vulnerability in Europe 2012107