Prediction of meteorological and hydrological drought under climate change in Minab Dam watershed

Document Type : Research

Authors

1 دانشگاه هرمزگاه خوابگاه دخترانه فاطمیه

2 University of Hormozgan

3 دانشگاه هرمزگان

4 Assistant Professor, Department of Statistics, Faculty of Basic Sciences, University of Hormozgan

10.22092/wmrj.2023.364078.1554

Abstract

One of the famous rainfall-runoff models that does not require a lot of input data is IHACRES. The aim of the current research is to investigate the effects of climate change on meteorological and hydrological drought in Minab Dam watershed. In this study, climatic and hydrological data related to the region including daily precipitation, average daily temperature and average daily discharge for modeling and simulating the daily discharge of the watershed. Minab was used during the statistical period from 1989 to 2018. From the Canadian model of the sixth report and three climate change scenarios SSP-1-2.5, SSP-3-7.5 and SSP-5-8.5, from the IHACRES model for predicting river flow for the future period from 2019 to 2040 and from the LARS-model WG was used for microscale precipitation and temperature. The Standardized Rainfall/Runoff Index (SPI/SRI) was used to study the drought and finally, the non-parametric Mann Kendall test was used to analyze the drought trend and its characteristics in the base and future periods. The IHACRES model was calibrated and after the appropriate performance of the model in the recalibration stage, the validation model and runoff were predicted for a period in the future using three scenarios of the 6th report. Then SPI and SRI values and drought characteristics including severity, duration, magnitude and peak were estimated for the past and future and their changes compared to the future period were compared. The results showed that the trend of rainfall changes for three scenarios in the autumn and winter season was decreasing, so that the most changes were related to the month of November using the three scenarios compared to the observation period, but in the summer season, these changes are increasing. Regarding temperature changes, all three scenarios predicted temperature changes, especially from August to December, up to 40% compared to the base period. Also, regarding the flow of the river, its trend is decreasing due to the decrease of rainfall and these changes are mostly related to the autumn and winter seasons, but its changes in the summer season have an increasing trend compared to the base period. In general, the trend of changes in precipitation and discharge in the entire period has an increasing slope. Investigating the effect of climate and meteorological drought in the study area showed that the hydrological and meteorological drought values have been increasing in the past, but in the future, in most scenarios, the drought trend is decreasing, which generally does not have a statistically significant trend.

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Articles in Press, Accepted Manuscript
Available Online from 21 December 2023
  • Receive Date: 12 November 2023
  • Revise Date: 03 December 2023
  • Accept Date: 21 December 2023