ارزیابی و پایش پدیده خشکسالی بر اساس دو شاخص SPI و SPEI در استان تهران

A drought is a long period of dryness in the natural climate cycle that can occur in any region of the world. This phenomenon appears gradually due to the decrease in rainfall, but factors such as poverty and improper use of land have also increased the vulnerability to drought. According to the objectives of the research, the data related to climatic factors affecting the phenomenon of dust (temperature, humidity, precipitation, evaporation, wind, number of days of dust) were collected, reconstructed, extended and completed in the form of SPI drought indicators. , SPEI was investigated and analyzed at the Mehrabad weather station in Tehran. . In this section, the days with dust as a dependent variable during the study period are compared with the simultaneous data of temperature, evaporation and rainfall as independent variables. The results of this part of the study will show the relationship of these variables from the aspect of climate effect on the dust phenomenon. In order to investigate dry and wet years and its effects on the increase or decrease of days with dust, using the SPI and SPEI indexes, the situation of drought years and periods are also investigated.