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A new monthly precipitation database has been developed for conterminous provinces in Spain by exploiting the total amount of data available at Spanish Meteorological Agency (AEMET, formerly INM). The new MOPREDAS (monthly precipitation database of Spain) database has been constructed by using all 6821 original data series that have been recorded for at least 10 years. These provide a total of 2670 complete, homogeneous series for the period 1946-2005, and are the most complete and extensive monthly precipitation dataset available in Spain at present. MOPREDAS has been created with the aim of analysing the behaviour of precipitation in the conterminous provinces of Spain, and to help validate the downscaling of climate models on a detailed spatial level. To this end, the station data were also interpolated on a regular grid, at 1/10 of degree of resolution, over the whole Spain. Trend analysis confirms great spatial and temporal variability in the behaviour of precipitation across Spain. The monthly precipitation trends vary from month to month, from coherent spatial trend patterns in March, June (both with a general and significant negative trend) and October (general positive trends), to highly regionalized trend patterns in July (with positive trends in north-west and mainly negative in the remainder), February and April (positive and negative trends in the south-east, respectively). These results suggest that both global and local factors affect the spatial distribution of trends in the Iberian Peninsula. Mountain ranges seem to be the most significant geographical factor in determining the spatial distribution of monthly trends on a detailed, sub-regional spatial scale. These results show that it is possible to accurately delineate the areas affected by different precipitation trends if a dense spatial database is available. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Abstract: We reviewed daily soil erosion data (mainly by rainfall erosion) in Western Mediterranean areas by compiling the data taken from the bibliography. Although soil erosion varies from site to site, and from year to year, annual amount of soil eroded depends on a few daily erosive events. Each year the three highest daily erosive events (ranked by magnitude) represent more than 50% of annual soil eroded, regardless of the total amount. This ratio is also evident on a supra-annual scale. The similarity of results from different environments, field methods and rainfall conditions suggests that the interpretation of annual average erosion rates should be viewed with caution. The dependence of soil erosion on a few daily erosive events should also be borne in mind when reconstructing the past, and suggests a new scenario in which historical geomorphology is replaced by a new catastrophism. [Copyright &y& Elsevier]