Scientific- Research Quarterly of Geographical Data (SEPEHR)

Scientific- Research Quarterly of Geographical Data (SEPEHR)

Monitoring and Evaluation of Frost Indexes and Prediction of the Beginning of Autumn Frosts in Iran (Case Study: Hamedan Province)

Document Type : Research Paper

Authors
Mehrdad Hosseini 1
Reza Borhani 1
Maryam Khattar 2
1 Master of Meteorology
2 Bachelor of Applied Physics
Abstract
In this research, in order to investigate the frosts occurred at Ekbatan station (Hamedan), the minimum daily temperatures of this station were studied. In general, the frosts were divided into three weak (mild), moderate, and severe categories. Next, the range of changes in the time of occurrence of these frosts was determined and the frequency of their occurrence was calculated. It was also attempted to obtain an experimental formula for the first autumn frost in a particular year based on the date of the last frosts of the spring of that year, and to determine the probability of occurrence of temperature thresholds between 0 and -15 ° C in different months of year by calculating different statistical parameters. In addition, it has been tried by dividing the the year into 36 distinct decades (ten days) to calculate the temperatures that are possible to occur with different percentages of probability.
Keywords
minimum of temperature
frost
Correlation
date of occurrence
Frequency
Ecbatan Station
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Scientific- Research Quarterly of Geographical Data (SEPEHR)
Volume 15, Issue 58
Summer 2006
Pages 22-27