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Despite the recent popularity of studying the effects of climate change on critical regions worldwide, there is a paucity of data documenting the results from trend analysis for these regions based on hydro‐climatic variables such as precipitation and temperature. The purpose of this study was to undertake a spatio‐temporal precipitation and temperature trend analysis for the Seyhan and Ceyhan River Basins located in the south of Turkey. The data for the seasonal and annual temperature variations (minimum, maximum and mean) and the total precipitation outputs obtained from the 14 stations in these basins are considered. The non‐parametric Mann–Kendall and the Mann–Kendall rank correlation tests are employed to determine the trend and its year of initiation. The linear slopes of the trends are calculated by using Sen's slope estimation technique and the spatial distributions for the slope of trends are presented. The results show that statistically significant upward trends exist for these basins based on the annual maximum temperature values, and the years of initiation of the trends are determined as mid‐1990 and mid‐2000. [ABSTRACT FROM AUTHOR]

ABSTRACT This study examines the spatial and temporal dynamics of wind speeds over Turkey by analysing data from 206 weather stations for a 32-year period (1975-2006). Trends in annual, seasonal, and monthly average wind speeds were determined using the Mann-Kendall trend test with the trend-free pre-whitening procedure. The strengths of trends were estimated by calculating the Sen's slope. The possible causes of wind speed changes were discussed. The analysis showed that the majority of the stations (73%) in Turkey had average wind speeds between 1.6 and 3.3 m s−1 during the 32-year period. From 1975 to 2006, 72% of stations had downward trends in annual average wind speeds. Downward trends were statistically significant at the 0.05 level for 62%. Significant upward trends were detected in only 16% of 206 stations. The rate of change in annual average wind speed data was on average −0.014 m s−1 year−1. The trends detected in monthly average wind speed data were mostly downward with an average strength between −0.007 and −0.017 m s−1 year−1. The directions and strengths of wind speed trends identified for the 1975-2006 period over Turkey are similar to the trends detected in wind speeds in many other regions over the earth. The changes in wind speeds in Turkey are most strongly related with the changes in general circulation patterns and air temperatures. The effects associated with changes in surface roughness and data quality are minor compared to other two factors. [ABSTRACT FROM AUTHOR]