Spatial and temporal variations of climatic growing season parameters in Western Anatolia

The temperature increase associated with anthropogenic climate change is expected to result in a number of climatic, meteorological and biological changes. One of these changes is related to the growing season parameters (growing season start, growing season end and growing season length). In this study, daily mean air temperatures from 35 meteorological stations in Western Anatolia were analyzed for the spatio-temporal change of the climatic growing season parameters during the period 1966–2015. Statistical significance of trends were assessed by non-parametric Mann-Kendall test and magnitudes of trends were quantifed by Sen's Slope Estimator. For series having significant serial correlation at %5 level and high coefficient of variation Trend-Free Prewhitening procedure were applied. The results showed that the beginning of the growing season (the end of the growing season) for all three threshold values delays (advances) from the southwest to the northeast. The growing season length increases from the northeast to the southwest. Temporally, the average start of the growing season for 5 °C, 7 °C and 10 °C base temperatures shifted 7.3, 10.0 and 10.5 days earlier, while the average end moved 4.8, 6.1 and 6.2 days later, increasing the length of the growing season by 12.0, 16.6 and 15.9 days, respectively. Key Words: Global warming, growing season parameters, trend analysis, western Anatolia.