environment
vahid safarian zengir; BATOL Zenali; Leyla Jafarzadeh Aliabad
Abstract
y in Ardabil province analyzed the precipitation data of 30 years from 1987 to 2016. Most of the precipitation occurred on 09/12/1991.Synoptic atmospheric maps of this date at a level of 500 Millibars were prepared by sea level elevation maps, geopotential heights, wind speed and direction, humidity, ...
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y in Ardabil province analyzed the precipitation data of 30 years from 1987 to 2016. Most of the precipitation occurred on 09/12/1991.Synoptic atmospheric maps of this date at a level of 500 Millibars were prepared by sea level elevation maps, geopotential heights, wind speed and direction, humidity, temperature, perceptible water on ground level and blocking (omega), using satellite images from NCEP/NCAR databases which Affiliating to the National Oceanographic Organization of the United States. The research method is a circular environmental approach. The results showed that in addition to the ground and climate conditions that have been effective in causing heavy rainfall during this history, the internal situation with the external pattern, such as the seas around and adjacent to Iran like the Black Sea and the Mediterranean has been affected. The monthly precipitation of Khalkhal station as a region that is more prevalent in the south of Ardebil province and southwest of the Caspian Sea in the three months of the spring season is more than February (1321/8 mm), March (1716.7 mm) and April (1448 mm). The most natural atmospheric hazards affected by heavy rainfall and flood damage in Khalkhal, inland, village, river and agricultural damages occurred during these months.
Batool Zeinali; Sayyad Sayyad Asghari- Saraskanrod
Volume 3, Issue 6 , October 2012, , Pages 103-116
Abstract
The purpose of this study was to investigate the changes in Urmia Lake water level as well as to determine the main factors in the reduction of Urmia Lake water through the multivariate statistical method of principal component analysis (PCA) and its effect on the urban around of Lake. For this purpose, ...
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The purpose of this study was to investigate the changes in Urmia Lake water level as well as to determine the main factors in the reduction of Urmia Lake water through the multivariate statistical method of principal component analysis (PCA) and its effect on the urban around of Lake. For this purpose, Landsat satellite images besides the data obtained from 29 variables in the statistical periods between 1970 and 2005 have been used. These variables include climate data, and monthly discharge of total basin and tourism situation of basin urban certainly Urmia. From the images, it can be recognized that the coastline has receded, particularly in East and South East, over the past 35 years (1975-2009). By the use of principal component analysis, six components with %78.8 of the total variance among the factors under study were identified as the main factors in the reduction of Urmia Lake water. The discharges in January, February, March, November, and December with %38.8 of the total variance were determined as the first component. Result indicated that The reduction of water level in Urmia Lake will cause many problems spatially in urban that are in distance of 40 KM Urmia Lake and also theirs that have wind direction of west and south west and are in east of lake. Grade of Urmia tourism has changed from one to four.
