Temporal and Spatial Variability in Surface Air Temperature and Diurnal Temperature Range in Spain over the Period 1950–2011

Abstract

Maximum (Tmax), minimum (Tmin), mean (Tmean) air temperature and diurnal temperature range (DTR) trends on a seasonal and annual time scale are evaluated from data recorded at nine Spanish weather stations during the period 1950–2011. Temporal and spatial variability in temperatures and in the diurnal temperature range (DTR) are presented. The non-parametric Theil-Sen approach and the Mann-Kendall test are used to evaluate anomaly temperature trends and their statistical significance, respectively. An air temperature reduction in Spain between 1950 and 1980 emerges and significant warming is observed between 1980 and 2011. On a seasonal scale, the weakest trends (mostly insignificant at the 5% confidence level) are noted during autumn, while the strongest warming rates were found during summer and spring. The rate of change between 1950 and 2011 in Tmax, Tmin and Tmean was 1.6 °C, 1.1 °C and 1.3 °C, respectively. DTR trends showed a decrease on the Mediterranean coast and a small change in northern, Atlantic and rural areas. The spatial distribution of annual and seasonal trends was plotted as isoline maps and strong trend gradients from the south to the north of the country are observed. DTR values were negatively correlated with relative humidity and precipitation and positively correlated with sunshine hours.

Erythemal Solar Irradiance, UVER, and UV Index from Ground-Based Data in Central Spain

“…In addition, between the maximum UVI below two and the daily dose above 2.5 SED, there are many days where the maximum UVI is below two but the daily dose is above 2.5 SED. Figure 7 shows that the damage threshold for fair skin is exceeded almost every day, including those for which maximum UVI is in the range 0.5 to 3 [23,24]. It can be seen that there are many days when UVI is below 3.0, but that the daily dose is above 10 SEDs and that on a few occasions it even reaches 14 SEDs.…”

“…for estimating UVER, UVI, cumulative doses, and sun protection impact when UVI is below three. Although the authors previously performed a study of radiative and meteorological variables in the same region in a rural area [23,24], the new characteristics and novelties of this work are that the present UVB measurement station is located in the city of Valladolid itself. Data were recorded every minute, with this being the first time that such research has been performed in this area using one-minute data as a measurement timescale.…”

Spatiotemporal Analysis of Diurnal Temperature Range: Effect of Urbanization, Cloud Cover, Solar Radiation, and Precipitation

“…Whan et al [20] focused on the effect of soil moisture on extreme maximum temperatures in southern-central and southeastern Europe for years 1984-2013 and found a 2-4 • C increase under dry soil moisture conditions compared to wet conditions [20]. A DTR analysis in Spain for the years 1950-2011 revealed a high decreasing DTR trend (−0.11 • C to −0.29 • C per decade) for stations located by the Mediterranean Sea [21]. Price et al [22] analyzed the long-term temperature data in Nicosia and Limassol in Cyprus for 1900-2000 showing a decrease of the DTR trend of −0.5 • C/100 years in the beginning of the century to −3.5 • C/100 years [22] by the end of the century, depending on the location.…”

Impact of Olive Trees on the Microclimatic and Edaphic Environment of the Understorey Durum Wheat in an Alley Orchard of the Mediterranean Area

“…Besides, there is an increasing need to improve the resilience of wheat to climate change, while providing ecosystem services in agreement with the requirements of the European Agricultural Policy. This is particularly relevant in the Mediterranean area, which has been identified as one of the most prominent "Hot-Spots" in future climate change projections [3,4], consisting of a marked decrease in precipitations, particularly during summer [5,6], associated with greater occurrence of spring/summer heat and drought stresses. The inter-annual weather variability is also expected to increase [7][8][9], while warming will enhance evapotranspiration and the potential incidence and severity of drought [10].…”