1- Ph.D. Student, Climatology, University of Isfahan, Isfahan, Iran
Abstract: (5963 Views)
This paper used the relevant data to study the frequency of thunderstorm occurrence in Tabriz as a sample of North West Iran’s climate. Where required, the methods such as Spearman rank correlation, linear and sixth order polynomial trend, as well as the cluster analysis according to the average linkage (within group) has also been applied utilizing the block distance standard for the monthly classification of the thunderstorm occurrence. The obtained results showed that the month of May, during various monthly time scales, and the spring season in seasonal intervals, undergo the majority of thunderstorm occurrences. The methodological statistics show that, secondary climatic features like hails, heavy showers, floods, and lightening are dominant climatic features in Tabriz during the thunderstorm occurrence. The above-mentioned climatic hazards are part of the characteristics of Tabriz climate and all of North West Iran, which bring about many economic, social and environmental damages, particularly for the farmers and animals farms. The probability distribution of thunderstorm occurrence in Tabriz indicates the irreversibility of their occurrence chiefly in short time return periods. Therefore, thunderstorms and their resulting secondary features are regarded to be a permanent hazard in Tabriz.
Received: 1901/12/14 | Accepted: 1901/12/14 | Published: 2009/07/26