Abstract. Trends of Mediterranean extreme temperatures are analysed for the period 1961-1990 based on daily station time series. Increases can be identified in the western Mediterranean area, whereas an opposite trend becomes apparent for the eastern Mediterranean region. Assessments of the 95th percentile of maximum temperatures in summer and of the 5th percentile of minimum temperatures in winter for the 21st century under enhanced greenhouse warming conditions are performed by means of statistical downscaling techniques. Mainly increases of both extreme indices result from these assessments, but considerable differences arise when using different predictors or predictor combinations, respectively. Furthermore, the results give strong indications that changes in temperature extremes do not follow a simple shift of the whole temperature distribution to higher values.

regions with decreasing totals but intensifying extremes, e.g. southern Europe and Turkey in winter and the Balkans in summer. The GPD based return values reveal slightly larger regions of increasing rainfall extremes than quantilebased indices, and the virtual stations from the weather generator show even stronger increases.

Changes of total precipitation, extreme precipitation, and dry periods in the Mediterranean area until the end of the twenty-first century have been assessed by means of statistical downscaling. Generalized linear models using predictors describing the large-scale atmospheric circulation as well as thermodynamic conditions have been applied for the projections under A1B and B1 scenario assumptions. The results mostly point to reductions of total and extreme precipitation over the western and central-northern Mediterranean areas in summer and autumn and to increases in winter. In contrast, over the eastern Mediterranean area widespread precipitation increases are assessed in summer and autumn, whereas reductions dominate in winter. In spring, total and extreme precipitation decreases prevail over the whole Mediterranean area. Total and extreme precipitation decreases mostly come along with increases of the maximum dry period length. Vice versa precipitation increases are commonly accompanied by a shortening of the maximum dry period length.

No abstract

Besides dynamical downscaling by regional climate models, statistical downscaling (SD) is a major tool to derive climate change projections on regional or even local scales. For the Mediterranean area, an increasing number of downscaling studies based on different statistical techniques have been published in the last two decades with a broad range of sometimes differing results relating to different variables and regional domains. This paper gives a short review of these Mediterranean downscaling studies mainly considering the following two aspects: (1) what kind of progress has been realized in this field since the early 1990s? The review addresses the inclusion of extremes in downscaling assessments, the development of probabilistic approaches, the extension of predictor sets, the use of ensembles for both dynamical model simulations and statistical model assessments, the consideration of nonstationarities in the predictor-predictand relationships, and some advances related to synoptic downscaling. (2) What are the main regional climate change signals in the Mediterranean area, considering agreed and controversial points also with respect to dynamical models? Best accordance among future projections can be found in seasonal temperatures with lower rates of warming in winter and spring, and, in most cases, higher ones in summer and autumn. Different results are obtained for the intra-annual range of extreme temperatures, but high-temperature conditions are generally expected to increase. Regarding seasonal precipitation, predominant reductions are indicated for spring, summer, and autumn. For winter, however, projections are distinctly different (GCMs: rainfall decrease; RCMs: increase only in the northernmost parts of the Mediterranean region; SD: widespread increases in the northern and western parts in several studies). Different results are obtained for rainfall extremes, but the entire precipitation distribution tends to shift towards higher and lower values. Apart from some sub-regional deviations, there is a predominant increase in future dry period durations. For near-surface winds, only a few studies are available, and they project some decline mainly for the winter season.