Hydrology
fatemeh ghavidel; Majid R.Banafsheh; Gholam Hasan Mohammadi
Abstract
The purpose of this research is to investigate the temporal changes and spatial distribution of the total cloud cover of the sky in the Ormia Lake drainage basin. In order to achieve the goals of this research, observational data on total cloud cover of the sky at five selected meteorological stations ...
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The purpose of this research is to investigate the temporal changes and spatial distribution of the total cloud cover of the sky in the Ormia Lake drainage basin. In order to achieve the goals of this research, observational data on total cloud cover of the sky at five selected meteorological stations and the product of total cloud cover of the sky (CFFCM) from MODIS sensors (Tera and Aqua) were used. The observed cloudiness values according to the ICAO standard were classified into five classes: cloudless sky, slightly cloudy, partly cloudy, semi-cloudy, and full cloudy, and the sky cloudiness changes were investigated. Pearson's correlation test was also used in order to investigate the relationship between the total cloud cover of the sky and the elements of precipitation, temperature, evaporation, and sunshine hours.The findings of the research showed that in the study area, the sky is mostly clear (28.7%) and slightly cloudy (23.9%), and only about 30% of the cases are semi-cloudy and full cloudy.In the examination of the frequency of occurrence of each of the cloudy classes, it was found that, in most cases, there was an increasing trend in the clear and slightly cloudy classes and a decreasing trend in the semi-cloudy and full cloudy classes.The study of the correlation coefficients between the total cloud cover of the sky and climatic parameters showed that there is a direct and significant relationship between the cloudiness of the sky and annual precipitation and an inverse relationship with temperature, evaporation, and sunshine hours, which is weaker in the case of annual temperature than the rest of the parameters, and also that the relationships established with observational data are more logical than those established with those established with satellite data. Investigating the spatial distribution of average seasonal cloudiness showed that cloudiness in winter and autumn is different from spring and especially summer. The highest amount of winter (summer) cloudiness is observed in the southern (northern) half of the Ormia Lake drainage basin, and this arrangement is consistent with the seasonal synoptic currents and the distribution of altitudes.
Mejid Rezaee Banafshe; Reza Abedi
Volume 2, Issue 4 , January 2017, , Pages 57-77
Abstract
Majid Rezaee Banafshe[1]* Reza Abedi[2] Abstract The process of deposition of sediment in the drainage basin which is the basic problems in the management of the drainage basin, has the nature of complex and needs to consider certain factors in the occurrence that can be To this end, in the present investigation ...
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Majid Rezaee Banafshe[1]* Reza Abedi[2] Abstract The process of deposition of sediment in the drainage basin which is the basic problems in the management of the drainage basin, has the nature of complex and needs to consider certain factors in the occurrence that can be To this end, in the present investigation ,initially suspended sediment discharge for days that data was not done, estimated by using flow discharge and sediment in genetic programming. And with the use of the criteria of assessment, genetic programming the most accurate method for estimating suspended sediment in the watershed case study towards the fitting curve exponent of the discharge of sediment had selected. Then fitting regression functions between the parameters of precipitation and an average discharge of flow with an average discharge of sediment in the program of SPSS 16 and modelling in genetic programming at seasonal studied. The results showed an average discharge of variable flow and suspended sediment discharge caused significant along with solidarity over 90% in most of the time intervals exist about study And between the variable precipitation and sediment discharge of suspended is established effect meaningful together with low correlation toward the hydrometric parameter (an average flow). The highest amount of correlation between precipitation and discharge of suspended sediment has been in the spring and the lowest amount of correlation between precipitation and suspended sediment discharge has been for the seasons of fall and winter. In planning the genetics3rd Brigade was used to model And according to the criteria of evaluation of the second model (The average flow of the discharge and suspended sediment discharge) Was shown The most accurate model than the models of the first (Precipitation and sediment discharge) and the third (The average flow of the discharge and rainfall with Discharge of suspended sediment). in most cases, Enter the variable rainfall combined with an average discharge of flow in model The accuracy of the model is to reduce. [1]- Associate Prof.; Faculty of Climatology; University of Tabriz (Corresponding author), Email:mrbanafsheh@yahoo.com. [2]- M.A Student; Department of Geography; University of Tabriz.
