Geomorphology
Leila Aghayary; Sayyad Asghari Saraskanrood; Batool Zeinali
Abstract
Flood is one of the most common natural hazards that causes many human and financial losses all over the world every year. In order to reduce the damages caused by floods and flood management, it is necessary to assess the possibility of danger and prepare maps of possible danger areas. Flood-flooding ...
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Flood is one of the most common natural hazards that causes many human and financial losses all over the world every year. In order to reduce the damages caused by floods and flood management, it is necessary to assess the possibility of danger and prepare maps of possible danger areas. Flood-flooding potential zoning is one of the methods that can be adopted to reduce the risks caused by floods. In recent years, many destructive floods have occurred in Garami county. For this reason, in order to manage floods, reduce damages and use water resources correctly, the flood potential of Germi county has been studied. In this study, 9 factors of slope, slope direction, height, precipitation, distance from the river, density of the river, lithology, distance from the city and village and land use were identified as effective factors for causing floods in the region. Standardization of maps was done using fuzzy method and zoning of prone areas was done with Aras multi-criteria algorithm in Edrisi software environment and according to the results of flood risk zoning; The criteria of lithology, land use, slope, distance from the river are the most important factors involved in creating the risk of subsidence of the study area with the weight coefficient of 0.853, 0.808, 0.674 and 0.4867 respectively, and 189.70 and 189.70 respectively. 20/388 square kilometers of the area has a very high probability of danger.
Mitra Amini; Hasan Lashkary; Mostafa Karampour; Zahra Hojaty
Volume 17, Issue 43 , October 2013, , Pages 1-20
Abstract
The aim of present study is the synoptic analysis of systems having by heavy precipitation on the Kashkan basin. After study of 34-years statistics from stations for basin and its environments three storms by maximum precipitation were selected. The results of study of weather maps, humidity, earth surface ...
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The aim of present study is the synoptic analysis of systems having by heavy precipitation on the Kashkan basin. After study of 34-years statistics from stations for basin and its environments three storms by maximum precipitation were selected. The results of study of weather maps, humidity, earth surface pressure difference and 850 hPa of 48 hours before and after storms, showed that with regard to the fact that three selected storms have out of heavy storms during statistics period occurred in various seasons of the year, their generating system was equal and Sudan-Mediterranean merger system pattern generated maximum precipitation. Synoptic conditions in three chosen storms are: 1-High pressure over Europe northwest and influx of the cold weather in higher latitudes toward low pressure that is situated in east Mediterranean, 2-Sudan low pressure nutrition and motion toward northeast. 3-Days that maximum precipitation has occurred in the basin. These low pressure systems are merged with each other in east of Iraq, and high pressure situated on east of Iran with influx of cold weather over Oman and Arab seas on the one hand and presence of anticyclone in Arabia have caused humidity transfer inside low pressure system situated over west of Iran and generated maximum precipitation.