Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades

Precipitation is one of the most changeable meteorological and hydrological phenomena. Estimating the  average annual number and the manner of rain fall time changes for management  and planning  changes of water resources in different regions is a necessary subject, So that the maximum or minimum e...

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Main Authors: Fatemeh Teimouri, omolbanin bazrafshan
Format: Article
Language:fas
Published: University of Sistan and Baluchestan 2017-09-01
Series:جغرافیا و توسعه
Subjects:
Online Access:https://gdij.usb.ac.ir/article_3367_c891900ae4915d9d7bdbb205c9e134d0.pdf
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author Fatemeh Teimouri
omolbanin bazrafshan
author_facet Fatemeh Teimouri
omolbanin bazrafshan
author_sort Fatemeh Teimouri
collection DOAJ
description Precipitation is one of the most changeable meteorological and hydrological phenomena. Estimating the  average annual number and the manner of rain fall time changes for management  and planning  changes of water resources in different regions is a necessary subject, So that the maximum or minimum exponential number with different objectives in water resources management has an important cultural, social and political consequences  in a country. In many resources, always numerical value of 240 to 250 mm of rainfall in the past few decades has been introduced. So on this basis to explore the accuracy of the above number; the aim of this study was to calculate the mean and variance of rainfall during the final decades in Iran. In this study, changes in precipitation over the last four decades in 33 synoptic stations with proper spatial distribution were studied. For temporal analysis of precipitation data , firstly their preliminary nature from the view of the uniformity, adequacy and stochastic were statistically analyzed And the average precipitation was calculated by Thiessen polygons and Isohyetal in different ways of Kriging interpolation, inverse distance and natural neighborhood, and using Leuven statistics, the heterogeneity of variances were compared  in different decades . Based on the results obtained, the average rainfall in Iran over the past four decades was estimated 421 mm  in Thiessen polygons method, 232 mm in Kriging method, IDW 715 mm and  Natural Neighbor Interpolation 715.5 mm .The results of the study of heterogeneity of variance in four decades showed that the variances are homogeneous and does not show a significant difference.Accordingly, it is proposed that the nominated method for estimating precipitation on the surface to be selected based on  the considered objective and accuracy.
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spelling doaj.art-e7e7b8024bc1491799872baae729c6072023-06-13T20:21:59ZfasUniversity of Sistan and Baluchestanجغرافیا و توسعه1735-07352676-77912017-09-01154817118810.22111/gdij.2017.33673367Analysis of Temporal Distribution of Rainfall in Iran Over the Past four DecadesFatemeh Teimouri0omolbanin bazrafshan1دانش‌آموخته کارشناسی ارشد،علوم ومهندسی آبخیزداری،دانشکده کشاورزی و منابع‌طبیعی،دانشگاه هرمزگان،بندرعباس ایرانfhormozgan univercityPrecipitation is one of the most changeable meteorological and hydrological phenomena. Estimating the  average annual number and the manner of rain fall time changes for management  and planning  changes of water resources in different regions is a necessary subject, So that the maximum or minimum exponential number with different objectives in water resources management has an important cultural, social and political consequences  in a country. In many resources, always numerical value of 240 to 250 mm of rainfall in the past few decades has been introduced. So on this basis to explore the accuracy of the above number; the aim of this study was to calculate the mean and variance of rainfall during the final decades in Iran. In this study, changes in precipitation over the last four decades in 33 synoptic stations with proper spatial distribution were studied. For temporal analysis of precipitation data , firstly their preliminary nature from the view of the uniformity, adequacy and stochastic were statistically analyzed And the average precipitation was calculated by Thiessen polygons and Isohyetal in different ways of Kriging interpolation, inverse distance and natural neighborhood, and using Leuven statistics, the heterogeneity of variances were compared  in different decades . Based on the results obtained, the average rainfall in Iran over the past four decades was estimated 421 mm  in Thiessen polygons method, 232 mm in Kriging method, IDW 715 mm and  Natural Neighbor Interpolation 715.5 mm .The results of the study of heterogeneity of variance in four decades showed that the variances are homogeneous and does not show a significant difference.Accordingly, it is proposed that the nominated method for estimating precipitation on the surface to be selected based on  the considered objective and accuracy.https://gdij.usb.ac.ir/article_3367_c891900ae4915d9d7bdbb205c9e134d0.pdfprecipitationtemporal distributionthiessen polygonsisohyetalheterogeneity of variances
spellingShingle Fatemeh Teimouri
omolbanin bazrafshan
Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
جغرافیا و توسعه
precipitation
temporal distribution
thiessen polygons
isohyetal
heterogeneity of variances
title Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
title_full Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
title_fullStr Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
title_full_unstemmed Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
title_short Analysis of Temporal Distribution of Rainfall in Iran Over the Past four Decades
title_sort analysis of temporal distribution of rainfall in iran over the past four decades
topic precipitation
temporal distribution
thiessen polygons
isohyetal
heterogeneity of variances
url https://gdij.usb.ac.ir/article_3367_c891900ae4915d9d7bdbb205c9e134d0.pdf
work_keys_str_mv AT fatemehteimouri analysisoftemporaldistributionofrainfalliniranoverthepastfourdecades
AT omolbaninbazrafshan analysisoftemporaldistributionofrainfalliniranoverthepastfourdecades