The temporal variability of precipitation in southern Spain was analysed to detect trends and cycles. The objectives of this study were (1) to determine whether there has been a decrease in precipitation in southern Spain and (2) to evaluate if any decrease is related to temporal cycles or is a well‐defined trend. The study was based on analysis of data series from nine monitoring stations in the Andalusia area of the Spanish Mediterranean. The Pettit test and temporal variability analyses were carried out using the temporal databases (1960–2006) from the selected stations. The results indicate that (1) there were significant differences in precipitation throughout the study period based on the location of the stations; (2) a negative trend in precipitation was observed for the east coast and inland stations, and an increasing trend in precipitation was observed for stations on the west coast; and (3) a general decreasing trend in seasonal precipitation, especially in winter, autumn, and spring, was observed for all stations except those on the west coast. Copyright © 2010 Royal Meteorological Society

Small portable rainfall simulators are considered a useful tool to analyze soil erosion processes in cultivated lands. European research groups in Spain (Valencia, Málaga, Lleida, Madrid and La Rioja), France (Reims) and Germany (Trier) have used different rainfall simulators (varying in drop size distribution and fall velocities, kinetic energy, plot forms and sizes, and field of application) to study soil loss, surface flow, runoff and infiltration coefficients in different experimental plots (Valencia, Montes de Málaga, Penedès, Campo Real and La Rioja in Spain, Champagne in France and Mosel-Ruwer valley in Germany). The measurements and experiments developed by these research teams give an overview of the variety of methodologies used in rainfall simulations to study the problem of soil erosion and describe the erosion features in different climatic environments, management practices and soil types. The aims of this study are: (i) to investigate where, how and why researchers from different wine-growing regions applied rainfall simulations with successful results as a tool to measure soil erosion processes; (ii) to make a qualitative comparison about the general soil erosion processes in European terroirs; (iii) to demonstrate the importance of the development of standard method for measurement of soil erosion processes in vineyards, using rainfall simulators; and (iv) and to analyze the key factors that should be taken into account to carry out rainfall simulations. The rainfall simulations in all cases allowed infiltration capacity, susceptibility of the soil to detachment and generation of sediment loads to runoff to be determined. Despite using small plots, the experiments were useful to analyze the influence of soil cover to reduce soil erosion, to make comparisons between different locations, and to evaluate the influence of different soil characteristics. The comparative analysis of the studies performed in different study areas points out the need to define an operational methodology to carry out rainfall simulations, which allows us to obtain representative and comparable results and to avoid errors in the interpretation in order to achieve comparable information about runoff and soil loss.

In southern Spain a longitudinal pluviometric gradient occurs under Mediterranean climatic conditions in an area that has at least two months of drought each year and very irregular rainfall. From the Strait of Gibraltar to the Cabo de Gata in Almería there is a reduction of more than 1,000 mm year⁻¹ in the mean annual rainfall. Analysis of the frequency and intensity of drought periods is necessary in regions where water resources are scarce and the ecosystem is highly dependent on water availability. Drought periods in the region described above were analysed using the DDSLR (Dry Days Since Last Rain) index to i) characterize trends in number of dry days and the amount of rainfall along the pluviometric gradient, ii) assess how the DDSLR index changes along the gradient from semiarid to humid Mediterranean regions, and iii) contribute to studies addressing the importance of climatic gradients in relation to the dynamics of various ecosystems. The DDSLR method enables calculation of the probability of the occurrence of dry days (days without rain) at any time of the year, assessment of the risk of water deficits for vegetation during plant growth periods, and evaluation of the temporal variability of hydrological/geomorphological processes that depend on soil moisture throughout the year. The results showed that there is a critical period of rainfall scarcity during September and October, which has implications for the availability of soil water resources for vegetation.In short‐term, the major problems are predicted for the Spanish Southern Mediterranean due to the increasing irregularity in precipitations: the number of days with no rains and drought periods are increased, but also a significant increment in the probabilities of extreme rainfalls exceeding 30 mm day⁻¹. Copyright © 2011 Royal Meteorological Society

In the Mediterranean environment, drought is one of the extreme phenomena that has most direct consequences and complexity. It also has a direct social impact through the mass media, whose analysis, typology and characterization should be a priority in strategies to plan and mitigate effects. The appearance of droughts is slow, their occurrence is often not recognized until human activity and the environment have already been significantly affected, and drought effects persist for a long time after the drought has ended. The spatial distribution of droughts is highly complex, and significant variation in drought conditions is common between different locations. This makes it difficult to identify similar regions, especially in areas of climate transition, where the atmospheric influences are complex. This is the situation in the Iberian Peninsula (particularly the south of the peninsula), which straddles both temperate and sub‐tropical climates and in which precipitation is highly variable and spatial variability is substantial. In this study, we analysed rainfall anomalies (Standardized Precipitation Index, SPI) over the last 50 years at four representative meteorological stations in southern Spain, two on the coast (Málaga and Algarrobo) and two at the headwaters of river basins regulated by dams (Antequera and Periana). The aims of the study were to (1) analyse the types of drought, and their frequency and intensity and (2) establish the dynamics and evolution of the social perception of droughts in the context of global change, brought about by the communications media. The results showed the SPI was a useful tool for identifying dry anomalies that may feature in our field of study of meteorological and hydrological drought, depending on its duration. Meteorological drought impact on the eco‐geomorphological system is common and has had a particular development since the 1980s. Hydrological droughts are those that have had the greatest effect on water reserves, particularly when they occur in the headwaters of the watershed covered by reservoirs. Their importance has increased since the 1980s. Determination of drought periods and its impact mass media could have extraordinary relevance as a mechanism to establish the levels of awareness on sustainable use of resources. For future research, other socioeconomic and demographic variables should be considered to know the link between drought and water deficit. Copyright © 2012 Royal Meteorological Society