Calculation of snow drought in Erzurum province using climate data and different index

Drought, which adversely affects water resources and disrupts the hydrological balance as a result of precipitation that is significantly below recorded normal levels, tends to develop slowly over a long period of time. The effects of this natural disaster are widespread and severe. Drought, which has been observed in recent years with increasing temperature and decreasing precipitation due to climate change, has reached a very serious dimension both in the world and in our country. The drought problem in our country constitutes a serious problem affecting human life, especially with its impact on the agricultural sector and ecosystem. In this regard, the drought studies are of great importance. Within the scope of this study, firstly, 45-year (1976-2021) climatic data of 17096/Erzurum Airport, 17666/Ispir, 17668/Oltu, 17688/Tortum, 17690/Horasan and 17740/Hınıs meteorological observation stations located within the borders of Erzurum province in the Eastern Anatolia Region of Türkiye where continental climate characteristics are observed were evaluated. When the trend analysis results of precipitation and temperature data, which are the two basic parameters of drought, are analyzed, a decreasing trend is observed for precipitation data, while an increasing trend is observed for temperature data. In the region where precipitation falls mostly as snow in winter and fall seasons, a decreasing trend is observed in all observation stations when snow height data are examined. In the second stage of the study, using climatic data, the distribution rates of drought categories over the years were determined for Erzurum province with meteorological and agricultural drought indexes SPI (Standardized Precipitation Index), SPEI (Standardized Precipitation Evapotranspiration Index) and SSPI (Standardized SnowPack Index) methods for 1, 3 and 12-month time periods. In addition, the maximum duration, severity and maximum magnitude of drought were determined. For each station, the results of the analysis obtained with different time periods and different drought indexes were compared and the relationships between them were evaluated. When the results of the three indexes in the study region are evaluated, the results are generally similar for the same time periods. It was determined that the duration and severity of drought increased in longer time periods. Drought is more pronounced in all stations after 2000. In general, SPI (Standardized Precipitation Index) and SPEI (Standardized Precipitation Evapotranspiration Index) analyses show drought in the south and northwest of Erzurum province, while SSPI (Standardized SnowPack Index) analysis shows snow drought from the center to the eastern part of the region.