Temperature and precipitation extremes’ variability in Turkey

Extreme weather events have become more frequent since the second half of the twentieth century. This study examines the long-term changes in temperature and precipitation extremes in two sequential periods over the period 1960–2019 using daily maximum, minimum, and mean temperatures and total precipitation for the four conventional seasons in Turkey. First, the Probability Density Function (PDF) for the mean temperature and precipitation are analyzed for the sequential periods. Second, extreme and relative value indices of the Expert Team on Climate Change Detection and Indices (ETCCDI) are used to evaluate changes in climate regions of Turkey for the considered period. A general upward trend in temperature indices is seen over the regions, but precipitation indices have more variable outcomes. The monthly minimum value of the daily maximum temperature (TXn) index has a 2 °C decades⁻¹ increase, and except for five stations, there is a 1 °C decades⁻¹ increase between the two sequential periods. While the annual total precipitation (RR ≥ 1 mm) (PRCPTOT) index has increased by 50 mm in the Black Sea, Continental-b and, Continental-c regions it has decreased in Mediterranean, Continental-a, and Transition regions. Similarly, very wet days (RR > 95th percentile) (R95p) and extremely wet days (RR > 99th percentile) (R99p) indices confirmed that the regions have not experienced an increase in extreme precipitation during the second half.