Climate change, potential evapotranspiration and moisture availability in the mediterranean basin

Abstract

Simple methods for estimating potential evapotranspiration, requiring only temperature and day length data, are compared by reference to the results from the Penman method. A modification of the Blaney and Criddle method, in which the c parameter is calculated from seasonal regression equations with the mean monthly temperature as the independent variable, is proposed and tested. It is found to work sufficiently well in the area of interest, the Mediterranean Basin. For a network of 248 Mediterranean temperature stations, present-day seasonal mean potential evapotranspiration is estimated by this method. Using the results from four equilibrium-mode general circulation models, seasonal mean scenarios of potential evapotranspiration per 1 "C rise in global mean temperature caused by the enhanced greenhouse effect are presented. Comparison of scenarios of the change in potential evapotranspiration and scenarios of the change in precipitation indicates an unfavourable shift in moisture availability due to the enhanced greenhouse effect, throughout the Mediterranean region.

Preliminary reconstructions of spring precipitation in southwestern Turkey from tree‐ring width

“…As trees are natural integrators of both temperature and precipitation, an intriguing avenue for our future research is to attempt reconstruction of potential evapotranspiration (e.g. Palutikof et al, 1994), a key variable for agriculture and water-resource management. advice and suggestions.…”

Climatic change on the Tibetan Plateau: Potential Evapotranspiration Trends from 1961–2000

“…GCMs are however not able to adequately simulate evaporative conditions (Hulme et al, 1992;Chattopadhyay and Hulme, 1997;Palutikof et al, 1994) and are available only at low spatial resolutions (>0.5 • ) that are barely able to resolve the major topographical features of the TP. In view of contrasting climatic trends on the TP any projections, recommendations and subsequent adjustments of crop irrigation will have to be made based on detailed spatial data sets that can portrait seasonal and regional changes in PET and precipitation regimes.…”

Decline in Mediterranean rainfall caused by weakening of Mediterranean cyclones

“…The current scientific assessment is that future climate change is likely to lead to a continuing reduction of moisture availability throughout the whole region (Palutikof et al, 1994). It is essential, therefore, to understand the mechanisms that link changes in the general circulation of a warming global climate and those directly involved in Mediterranean rain events.…”