8th Atmospheric Sciences Symposium, İstanbul, Turkey, 1 - 04 November 2017, pp.556-566
In this study, we have run the RClimDex software to calculate 7 precipitation extreme indices at 6 stations in the Marmara region for the period from 1960 to 2016. These indices have shown decreasing trends in consecutive dry days and increasing trends in annual rainfall, rainfall intensity. The wet spell duration shows an insignificant positive trend over the most study stations of the Marmara which are affected by the fast rate of urbanization such as Istanbul, Bursa, and Tekirdag, while it is decreased for the stations of Kocaeli and Çanakkale. The trend of annual total precipitation indicator shows an insignificant positive trend all over the Marmara region except for the Çanakkale station. Annual precipitation trend was significant only for two urban stations of Sarier and Bursa at 90% level of confidence. The maximum one-day and 5 days and the heavy precipitation revealed a significant positive trend at 5% significant level for Edirne and Tekirdag by a mean rate of 2.8 and 5.4 mm per decades and for Bursa by a mean rate of 0.6 day per decades, respectively. Therefore, a large proportion of study stations have experienced an increase in the annual precipitation, heavy precipitation events, although the percentage of significant trend values was very low. In the Marmara region is expected that the rainfall events tend to change toward shorter and more intense spells of rainfall. Overall, there is a much more mixed pattern of changes in precipitation extreme trends at the station scales.