Razieh Saboohi; Hossein Barani; Morteza Khodagholi; Ahmad Abedi Sarvestani; Asghar Tahmasebi
Abstract
Climate change is one of the most important phenomena in recent years have been affected on natural resources and especially the communities whose livelihoods in relation to natural resources, as well as prediction of climate parameters in order to achieve future changes and regard to adaptations to ...
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Climate change is one of the most important phenomena in recent years have been affected on natural resources and especially the communities whose livelihoods in relation to natural resources, as well as prediction of climate parameters in order to achieve future changes and regard to adaptations to deal with climate change is interest of researchers. Therefore, in this study with purpose of previous trend analysis and prediction of precipitation, mean minimum and maximum temperature were used non-parametric Mann-Kendall test and General Circulation Models, HadCM3, respectively. For this purpose, the output data of HadCM3 with three scenarios A1B, A2 and B1 by LARS-WG model were downscale in Semirom region. The results showed that temperature parameters (mean temperature, mean minimum and mean maximum temperature) had increased trend in winter, autumn seasons and annual scale in six studied stations and temperature parameters showed different trend in spring and summer seasons and the annual precipitation is showed negative trend in most of the stations. Also, the results of minimum temperature prediction showed that minimum temperature will generally increase with three scenarios during 21 century and the largest increase in mean minimum temperature compared to the current period is observed in November with more than 0.8 °C increase. The maximum temperature prediction represents a change in the maximum temperature threshold and warming this century in all months of the year, except January and precipitation will increase in all months except June and September using all three scenarios.
Bahare Shirani; Morteza Khodagholi; Majid Montazeri
Abstract
Among the widespread studies have made on drought, rangelands drought has just received little attention. This study investigates the effect of drought on rangelands of Isfahan province. For this, Standardized Precipitation Index (SPI), Rainfall Anomally Index(RAI), Percentage of difference between the ...
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Among the widespread studies have made on drought, rangelands drought has just received little attention. This study investigates the effect of drought on rangelands of Isfahan province. For this, Standardized Precipitation Index (SPI), Rainfall Anomally Index(RAI), Percentage of difference between the measured rainfall and Statistical Index Annual Precipitation(SIAP) were assessed in different time periods and their relation with these type of rangelands production in Isfahan province were studied. In this study, the monthly precipitation data in Esfahan, Meyme and Shahreza stations and forage production data in Charmshahr, Moote, Gardaneshadian rangelands in the period 1998-2007 were used. To investigate the relationship between indices and pastures production, the Pearson correlation was used. The results showed that only in Moote pasture, there were significant relationship and in the other pastures due to the special conditions, there was no correlation between these two variables The results indicate that effect of time periods were more than effect of indexes and spring rains have the greatest effect on the production of rangelands with Artemisia sieberi type in Isfahan province. Finally, the percentage of difference between rainfall in the range 3 month with 0.867 and then RAI 3 with 0.863 and SPI 3 with 0.802 were determined as the most appropriate index of drought.
