Monitoring temporal-spatial changes of meteorological drought and trend analysis of climatic variables in Khuzestan province from 2000 to 2020

Reducing the effects of drought and optimal management of water resources is affected by the forecast of regional planners of areas affected by the risk of drought, so the evaluation and study of this phenomenon can be very important. Therefore, this study was conducted to Monitor temporal-spatial changes of meteorological drought and trend analysis of climatic variables in Khuzestan province during the period 2000 to 2020 using the SPEI index and ArcMap, XLSTAT, and RStudio software. Two non-parametric methods including Mann-Kendall and Sen's estimator slope methods were used here to analyze the annual trends of data. After calculating the drought, the effect of this phenomenon on the water area of Horul Azim and Shadgan wetlands in 2000, 2006, 2015, and 2020 was investigated. The results showed that there is a direct relationship between the changes in the wetlands cover and the problem of drought, and with the increase of drought, the water cover of the wetlands decreases and with the increase of drought, the area of water in the wetlands increases. The results also showed that the analysis of the trend of changes resulting from Sen’s slope for precipitation and temperature in the stations varied between -1.87 and 3.38 and 0.016 and 2.25, respectively. The highest slope of changes with increasing rainfall was observed in the western and central regions of the province and the slope of negative changes in rainfall has often occurred in the southern regions. Also, temperature analysis with this test showed that the temperature in all stations with a relatively slow slope in the study period had a positive and increasing trend. It is worth mentioning that the existence of increasing and decreasing trends indicates the existence of climate change, so it is necessary to study this issue and provide solutions to water resources management in times of crisis. The increasing and decreasing trend indicates the existence of climatic changes and fluctuations; Therefore, investigating this issue and providing solutions to manage water resources in times of crisis seems essential.