Bromand Salahi; Mahnaz Saber; Abbas Mofidi
Abstract
In this study, the perspective of reference crop evapotranspiration (ETo) in the southern part of the Aras River Basin under climate change condition was drawn using SDSM downscaling. For this purpose, meteorological data of selected synoptic stations located in this basin were used and after receiving ...
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In this study, the perspective of reference crop evapotranspiration (ETo) in the southern part of the Aras River Basin under climate change condition was drawn using SDSM downscaling. For this purpose, meteorological data of selected synoptic stations located in this basin were used and after receiving the downscaling outputs for the parameters required for estimating ETo by Penman-Monteith FAO-56, basin ETo was calculated for the near future (2021-2050). In this regard, daily reanalysis NCEP data and station daily data include: maximum and minimum temperature, wind speed, relative humidity and sunshine hours as well as output data on CanESM2 model under RCPs scenarios were used to generate future station data for estimate Aras Basin ETo. The studied stations included: Ahar, Ardabil, Parsabad, Jolfa, Khoy and Makoo and the base period for the data was considered 1985-2005. First, the efficiency of SDSM in simulating the parameters required for ETo estimation was evaluated by comparing NCEP simulated data with station data. Their comparison indicated the appropriate performance of the model in simulating data. Therefore, climatic parameters were simulated using the CanESM2 model under RCPs scenarios for the future. After calculating their monthly values, in CROPWAT was entered to estimate the basin ETo and trend of the variable for the next three decades were calculated. The results showed that the basin ETo in the future period compared to the base period will increase by an average of about 7 mm per year. In terms of stations, there will be an increase in Parsabad (102 mm) and Jolfa (66 mm). This increase also means an increase in the water needs of plants. Also, the future trends of ETo in Khoy, Makoo, Ahar and Ardabil will be decreasing.
Abdorrahim Fazeli khiavi; Bromand Salahi; Masoud Goodarzi
Abstract
Climate change is an effective phenomenon on many natural processes, including hydrologic cycle. The evapotranspiration as one of the parts of the hydrologic cycle will be at the forefront of these changes. Due to the importance of evapotranspiration in water resources management and agricultural planning, ...
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Climate change is an effective phenomenon on many natural processes, including hydrologic cycle. The evapotranspiration as one of the parts of the hydrologic cycle will be at the forefront of these changes. Due to the importance of evapotranspiration in water resources management and agricultural planning, the present study was conducted to investigate the effect of climate change on this parameter in Moghan Plain. For this purpose, the HadGEM2 atmospheric and oceanic circulation model was used under RCPS and Lars-WG6 downscaling in 2011-2030 and 2030-2060 periods. Also, Penman-Monteith and Hargreaves-Samani methods were used to calculate evapotranspiration. This study showed an increase of 6 to 8.4% of calculated evapotranspiration with Penman-Monteith method in each of the scenarios in 2030-2011 and 2030-2060 periods compared to the observed years. Also, calculated evapotranspiration of the Hargreaves-Samani method will increase from 4.5 to 7.7% in each scenario in 2030-2011 and 2030-2030 periods compared to the observation years. These increases affects on water demands of Moghan and Khodafarin irrigation and drainage networks in the maximum months, which requires appropriate solutions to adapt to climate change conditions.
Boroumand Salahi; Massoud Goudarzi; Seyed Asaad Hosseini
Abstract
Predicting the temperature and precipitation changes is necessary for assessing the change in the future and to mitigate the harmful impacts of climate change on water resources and agriculture, environmental, economic and social issues. Accordingly atmospheric general circulation models (GCMs) have ...
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Predicting the temperature and precipitation changes is necessary for assessing the change in the future and to mitigate the harmful impacts of climate change on water resources and agriculture, environmental, economic and social issues. Accordingly atmospheric general circulation models (GCMs) have been developed for simulation of climatic parameters. In this research, output data of HadCM3 general circulation model (with three climate change scenarios A1B, A2 and B1) were downscaled using LARS-WG Statistical Model in selected stations of the Urmia Lake Basin and Results has been evaluated and analyzed from three selected synoptic stations, including Saghez, Tabriz and Urmia stations in the base period (1961-1990) and the 2050 (2046-2065) for three variables minimum temperature, maximum temperature and precipitation. In LARS-WG model analysis, evaluation of the amount of MSE, RMSE, MAE indexes were done and correlation coefficients were determined. The conclusion can be presented herein that: the model was fit for the region. The overall results for 20 years of 2050s, indicate a decrease of 12.1 percent in precipitation and also 1.3 Celsius degrees would be increased in temperature compared to the base period. In the study area, the highest maximum temperature increase would be in Tabriz synoptic stations and the highest minimum temperature and highest decries precipitation would occur in Urmia station. The results of this study would help enormous the policymakers and planners for water resources in the future.
