Droughts as destructive climatic extreme events affect natural environment of an area. Identifying droughts has a vital importance in the planning and management of water resource systems of a river basin. This study investigates the trends of maximum hydrologic drought variables, annual maximum duration (AMD), and annual maximum severity (AMS), by using Mann–Kendall, modified Mann–Kendall, and recently developed Şen's innovative trend analysis (ITA) methods. These methods are applied to the AMD and AMS of nine different stations located in Coruh River Basin, Turkey, in which numerous highly critical power plants have recently been constructed, under construction, or planned. Basic Mann–Kendall test indicated no trend in the investigated stations while the modified Mann–Kendall gave significantly decreasing trend for AMS series of station 2304 and for AMD series of station 2321 at 10% significance level. Modified Mann–Kendall and ITA approaches indicate that the AMS of station 2304 show significantly decreasing trend. According to the ITA method, the peak AMS values of the stations 2315 and 2322 have also significantly decreasing trend after 1986. Both modified MK and ITA methods provide increasing trends in drought severities of the stations 2316 and 2323. It should be noted that some droughts or water stress may be occurred in these stations in the future. Modified Mann–Kendall test provides no significant trend for the seven stations while ITA results indicated some positive or negative trends at these stations. The primary points of interest of Şen's ITA method are that it is not subject to any assumption such as serial relationship, non‐normality, sample size, and trends of low, medium, and high data can be seen by this method easily. The study indicates that the ITA method could be simply and successfully used by hydrologist or water resources decision makers or in identifying droughts to prepare efficient management plans. Copyright © 2016 John Wiley & Sons, Ltd.

No abstract

No abstract

No abstract

Climate change, one of the major environmental challenges facing mankind, has caused intermittent droughts in many regions resulting in reduced water resources. This study investigated the impact of climate change on the characteristics (occurrence, duration, and severity) of meteorological drought across Ankara, Turkey. To this end, the observed monthly rainfall series from five meteorology stations scattered across Ankara Province as well as dynamically downscaled outputs of three global climate models that run under RCP 4.5 and RCP 8.5 scenarios was used to attain the well-known SPI series during the reference period of 1986–2018 and the future period of 2018–2050, respectively. Analyzing drought features in two time periods generally indicated the higher probability of occurrence of drought in the future period. The results showed that the duration of mild droughts may increase, and extreme droughts will occur with longer durations and larger severities. Moreover, joint return period analysis through different copula functions revealed that the return period of mild droughts will remain the same in the near future, while it declines by 12% over extreme droughts in the near future.