نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه علوم و مهندسی آب، دانشکده مهندسی آب و خاک، دانشگاه علوم کشاورزی و منایع طبیعی گرگان، گرگان، ایران.
2 گروه علوم و مهندسی آب، دانشکده کشاورزی دانشگاه فردوسی مشهد. مشهد .ایران
3 دانشیار آبیاری و زهکشی گروه مهندسی آب دانشگاه علوم کشاورزی و منابع طبیعی گرگان.شهر گرگان. ایران
4 گروه اقتصاد کشاورزی، دانشکده کشاورزی، دانشگاه زابل، زابل، ایران
5 شرکت مدیریت منابع آب ایران، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Determining the future climate situation by using climate models seems necessary to consider in the field of adaptation or reducing the adverse effects of climate change. In this research, the temporal trend of rainfall, minimum and maximum temperature in the four stations in the Qarasu basin and in addition to, investigated using Thiessen's interpolation method. Among the five models of the CMIP6, three models were selected as the best models and used for MME. Biass Correction was done with CMHyd software for scenarios SSP2-4.5 and SSP5-8.5 in periods 2026-2050, 2051-2075 and 2076-2100. The trend of variables in the base period (1990-2014) and future were investigated with Mann-Kendall test and sens slope. The results of analysis significant trends annual average maximum and minimum temperature of all stations and in catchment area according to SSP2.4-5 scenario in two near and middle future periods and for SSP5-8.5 scenario in all three future periods have a significant trend at the 99% level. In analysis significant trend seasonal rainfall according to SSP2.4-5 scenario in the summer season distant future all stations and in near future of the station area of Gorgan regional water company at the 95% level and for the SSP5-8.5 scenario only in the winter season in the distant future Ghafarhaji station has a significant trend at the 99% level. The future monthly rainfall in the catchment area according to scenario of SSP2.4-5 in August at the 99% probability level and SSP5-8.5 in March at the 95% probability level have a significant trend.
کلیدواژهها [English]
EXTENDED ABSTRACT
Determining the future climate situation by using climate models with emphasis on temperature and precipitation seems necessary to consider the necessary measures in the field of adaptation or reducing the adverse effects of climate change.
In this research, the temporal trend of rainfall, minimum temperature and maximum temperature in the four stations of Hashemabad, Aqqla, Ghafarhaji and the area of Gorgan Water Department in the Qarasu basin of Golestan province have been investigated. In addition to point methods, Thiessen's interpolation method and geostatistics were used in the regional scale for rainfall and temperature. In this method, in addition to the value of the variable at the measurement station, its relationship with the value and position of the variable at other stations is considered. The performance of the models was evaluated based on the correlation coefficient (R), root mean square error (RMSE), root mean square error (MBE), mean absolute error (MAE), Nash-Sutcliffe Efficiency (NSE) and Kling Gupta Efficiency (KGE). Among the five models of the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6), three models, MIROC-ES2L, ACCESS-CM2, and MIROC6, were selected as the best models and were used by the arithmetic mean method for Multi Model Ensemble (MME). Downscaling Correction was done with CMHyd (Climate Model data for hydrologic modeling) tool for two scenarios SSP2-4.5 and SSP5-8.5 in three periods of the near future (2026-2050), middle (2051-2075) and long term (2076-2100). The trend of the parameters of maximum temperature, minimum temperature and precipitation in the historical period (1990-2014) and the future periods were investigated by Mann-Kendall and sens slope tests.
The results of the analysis of the significant trends of the annual average data of the maximum temperature and the minimum temperature of all stations and in the catchment area according to under the SSP2.4-5 scenario in the two near and middle future periods and for the SSP5-8.5 scenario in all three future periods have a significant trend at the 99% level. The annual average of the precipitation parameter in the observation period and future periods under both scenarios lacks a significant trend. In the analysis of the significant trend of the seasonal average of the maximum and minimum temperature parameters of the SSP2.4-5 scenario in autumn, spring and summer and the SSP5-8.5 scenario in all seasons of the future periods there is a significant trend. seasonal rainfall data under the SSP2.4-5 scenario in the summer season in the distant future of all stations and in the near future of the station of the area of Gorgan regional water company at the 95% level and for the SSP5-8.5 scenario only in the winter season in the distant future Ghafarhaji station has a significant trend at the 99% level. In the analysis of the significant trend of the monthly rainfall data of the SSP2.4-5 and SSP5-8.5 scenarios, the catchment area has a significant trend only in the month of August at the 99% probability level and in the month of March at the 95% probability level respectively.
In general, the investigation of temperature and precipitation in the future of the Gharesou basin under two scenarios and three future periods has brought a significant increase in the level of 95 and 99% for the temperature parameter and different results for the precipitation parameter. As expected, the increase in temperature is more evident in the SSP5-8.5 scenario than in the SSP2-4.5 scenario.