Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation

The aim of this study is to assess some synoptic characteristics of heavy precipitations in southwestern parts of Iran and evaluate the relationship between them with the Madden-Julian Oscillation (MJO). Research is conducted with regard to distribution of precipitation per month and identifying the...

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Main Authors: S.M.J. Nazemosadat, K. Shahgholian
Format: Article
Language:fas
Published: Ferdowsi University of Mashhad 2015-06-01
Series:مجله آب و خاک
Subjects:
Online Access:http://jsw.um.ac.ir/index.php/jsw/article/view/28595
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author S.M.J. Nazemosadat
K. Shahgholian
author_facet S.M.J. Nazemosadat
K. Shahgholian
author_sort S.M.J. Nazemosadat
collection DOAJ
description The aim of this study is to assess some synoptic characteristics of heavy precipitations in southwestern parts of Iran and evaluate the relationship between them with the Madden-Julian Oscillation (MJO). Research is conducted with regard to distribution of precipitation per month and identifying their steam sources. Daily records of the November-April precipitation data in Abadan, Ahwaz, Bandar-Abbas, Bushehr, Shahr-e-kord and Shiraz stations for the 1975- 2011 period are collected as well as same panel data for Yasuj station from 1990 to 2011. Rainfall data are sorted in descending order and precipitation values that were fallen within the 5% and 10% of highest records are categorized as the heavy precipitation. The most frequent precipitations occurred in January, February and December. The most frequent heavy precipitations in Ahwaz, Bandar-Abbas, Bushehr, Shahr-e-kord and Shiraz stations occurred in phase 8, while in Abadan station occurred in phases 7 and 8. Apparently, due to the short duration precipitations data at Yasuj station, the most frequent heavy precipitation observed in phase 2.Synoptic maps show that harmonized with eastward movement of convective precipitation in Indian or pacific oceans.Heavy precipitation forms in the west region of Iran and moves toward southwest and south Central of Iran and then appears to Afghanistan.Formation of a cyclonic circulation that encompasses the Mediterranean Sea, Red Sea and Persian Gulf plays an important role for moisture supplement of these storm activities. The synoptic maps have indicated that main sources of these heavy rainfalls are moisture produced at the Arab sea and western parts of the Indian Ocean.
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spelling doaj.art-f2180fd211924abdafe38f18df072c012022-12-21T22:53:43ZfasFerdowsi University of Mashhadمجله آب و خاک2008-47572423-396X2015-06-012851072108310.22067/jsw.v0i0.285958321Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian OscillationS.M.J. Nazemosadat0K. Shahgholian1Shiraz UniversityShiraz UniversityThe aim of this study is to assess some synoptic characteristics of heavy precipitations in southwestern parts of Iran and evaluate the relationship between them with the Madden-Julian Oscillation (MJO). Research is conducted with regard to distribution of precipitation per month and identifying their steam sources. Daily records of the November-April precipitation data in Abadan, Ahwaz, Bandar-Abbas, Bushehr, Shahr-e-kord and Shiraz stations for the 1975- 2011 period are collected as well as same panel data for Yasuj station from 1990 to 2011. Rainfall data are sorted in descending order and precipitation values that were fallen within the 5% and 10% of highest records are categorized as the heavy precipitation. The most frequent precipitations occurred in January, February and December. The most frequent heavy precipitations in Ahwaz, Bandar-Abbas, Bushehr, Shahr-e-kord and Shiraz stations occurred in phase 8, while in Abadan station occurred in phases 7 and 8. Apparently, due to the short duration precipitations data at Yasuj station, the most frequent heavy precipitation observed in phase 2.Synoptic maps show that harmonized with eastward movement of convective precipitation in Indian or pacific oceans.Heavy precipitation forms in the west region of Iran and moves toward southwest and south Central of Iran and then appears to Afghanistan.Formation of a cyclonic circulation that encompasses the Mediterranean Sea, Red Sea and Persian Gulf plays an important role for moisture supplement of these storm activities. The synoptic maps have indicated that main sources of these heavy rainfalls are moisture produced at the Arab sea and western parts of the Indian Ocean.http://jsw.um.ac.ir/index.php/jsw/article/view/28595IranMJO, Persian GulfPrecipitationVector winds
spellingShingle S.M.J. Nazemosadat
K. Shahgholian
Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
مجله آب و خاک
Iran
MJO, Persian Gulf
Precipitation
Vector winds
title Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
title_full Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
title_fullStr Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
title_full_unstemmed Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
title_short Formation of Heavy Precipitations in Southwestern Part of Iran and its Association with the Madden-Julian Oscillation
title_sort formation of heavy precipitations in southwestern part of iran and its association with the madden julian oscillation
topic Iran
MJO, Persian Gulf
Precipitation
Vector winds
url http://jsw.um.ac.ir/index.php/jsw/article/view/28595
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AT kshahgholian formationofheavyprecipitationsinsouthwesternpartofirananditsassociationwiththemaddenjulianoscillation