Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Iran → Statistical synoptic analysis of early heat waves of in northwest Iran during the past the last half century

University of Mohaghegh Ardabili (2017)

Statistical synoptic analysis of early heat waves of in northwest Iran during the past the last half century

Hooshyar, Mahmood

Titre : Statistical synoptic analysis of early heat waves of in northwest Iran during the past the last half century

تحلیل آماری ـ سینوپتیکی امواج گرمایی زودرس شمال غرب ایران طی نیمقرن اخیر

Auteur : Hooshyar, Mahmood

Université de soutenance : University of Mohaghegh Ardabili

Grade : Doctoral Thesis 2017

Résumé
The phenomenon of early heat waves is one of the climatological events which has greatly damaged natural resources including farming products and fruits, and decreased production and increased herbal pesticide. It has also affected human resources particularly human health. Given this, it is imperative to deal with the damage of this phenomenon by recognizing the characteristics of heat waves. The purpose of this study is to identify early hot waves and atmospheric systems which play a role in the phenomenon of early heat waves of North-east of Iran in a constant scale. In so doing, the data of the daily maximum temperature of the Month of Esfand of 14 Sino Petic stations in North-east of Iran was used in solar statistical periods of 1333-1392. Then based on the defined threshold of Baldy Index 61 days of heat were chosen. All the statistical characteristics of the data were processed in SPSS software program. Prior to the factor analysis, and identification of patterns , the course of early of heat in North-east of Iran was investigated. The findings showed that extreme temperatures in all target stations were increasing. Following this, the altitude data of middle alignment of the atmosphere were extracted on a network equal to 2.5×2.5 degree an arch in an area from 0 to 70 degree eastern latitude and from 0 to 60 degree north latitude from NCEP/NCAR data bases. A matrix in 864 columns in 40 rows was formed on which days with heat waves and the altitude data of middle alignment of the atmosphere were placed on rows and columns respectively. Then 10 components which accounted for 93 out of 500 hPa of alignment of changes of height of pressure were identified. In order to identify the patterns in a constant scale on the scores of the components, cluster analysis was performed through WARD method. Totally, 5 patterns of productive pressure of early hot waves were identified. The results of the study showed that heat waves in North-east of Iran was the result of high latitude in South Saudi Arabia, Aden Strait and Sudan center at 500 hPa level, and forming low pressure in Sudan at sea level as well as pulling them toward North and North-east of the region (North-east of Iran) under the study

Présentation

Version intégrale (1 Mb)

Page publiée le 19 avril 2020