جستاري پيرامون سختي اقليم زمستاني تبريز و ارتباط آن با نوسانات شمالگان

A Query on the Severity of Winter Climate in Tabriz and Its Relationship with Arctic Oscillations

Arctic Oscillations (AO) are regarded as the influential factors in the changing climatic pattern of winters in northern hemisphere. In this research, we studied the relationship between winter severity in Tabriz and the climatic pattern using the data for winter climatic variables and the Sea Level Pressure (SLP) fluctuations index in the Arctic Ocean. The Spearman rank correlation was applied in order to find the relationship between the winter severity and the pattern. The results indicated the existence of a teleconnection correlation. After the calculation of the Winter Severity Index (WSI) for Tabriz, its polynomial trend was graphed, which shows a reducing trend indicating a reduction in the severity of winters and changing into temperate climate in Tabriz. Other reason for such a reduction is the declining trend of climatic factors like the number of snowy and freezing days, as well as the increasing trend of winter temperature. Based on the significant correlation between the AO Index and the climatic factors such as temperature, precipitation, snowy days and WSI. we might attribute the AO to the severity and/or temperateness of winters in Tabriz.