Analysis of Greenhouse Gas Emission Scenariosin the Plains Part of Haraz Watershed in Mazandaran Province

In order to achieve the objectives of this study and according to the statistics of existing stations, for research about the phenomenon of climate change in the plains of Haraz watershed of Mazandaran province have been used LARS-WG5 model and three scenarios A1B, A2, B1 and each in three series 2011, 2065-2046 and 2099-2080. By determining the 30-year base year from the statistics of the nearest synoptic station to this study area, the average monthly precipitation and temperature were simulated.According to the results of this study, very irregularly increasing changes in rainfall in October, November and January and decreasing changes in August in the period of 2095-2080 are expected in the area. In the case of temperature changes in the watershed of Haraz plains area in the period 2095-2080 for scenarios A1B, A2 and B1, the trend of increasing the average monthly temperature shows even more than the two previously studied periods, so that the average temperature of July and August in the next period 2099-2080 by scenario A1B with 30/44 and 31/03, respectively, that it will reach 30 higher degrees Celsius and the average temperature in January and December will increase to 11.08 and 12.55 with an increase compared to the base period. The increase in temperature in the summer months, which coincides with the decrease in rainfall, has a significant role in the agriculture of this region, which is one of the important rice production areas of the country, and affects the downstream hydrological cycle of Haraz watershed. On the other hand, winter temperature changes can affect the time of snow melting in the basin, which has a significant effect on the peak flood discharge downstream of the watershed.