The Analysis of the Effect of Patterns and Teleconnection Indicators on Drought in the Province of Golestan

Drought is a natural disaster which has tremendouly affected many countries. It can create problems in the economic, social, political and cultural sections of a country. Different factors such as teleconnection and climate indicators can cause drought in a region. In the current study, precipitation data of 39 rain gauges and meteorological stations in the province of Golestan, which had long-term statistics with 33 common year (1982-2014), were used to detect drought and wet years using teleconnection indices and Z indicator. The findings indicated that in April with 5% significance of the stations, in March with 15%, in December with 31%, in May with 41%, and in August with 55% of sinficance of reseach statations, the process of change in the Z precipitation indicator of rainfall, was significantly decresing. This indicated that drought had incresed in the the studied months in the stations of the province. The results also showed that the positive (negative) phases of North Atlantic Oscillation, polar patterns, Atlantic Oscillation in the recent decades,EastAtlantic/Western Russiateleconnectionpattern, North Sea Oscillation, and Scandinavian pattern had strengthened wet years (droughts). While the positive (negative) phases of the Antarctic oscillation, the eastern Atlantic pattern, and the sea surface temperature of the tropical North Atlantic were associated with the drought (wet year) occurrence. The findings of the present study can be a step forward to help control and manage the water resources of the province. In fact, by the proper recognition of the relationship between teleconnection patterns and rainfall in the province of Golestan, a proper prediction of the rainfall variation in the coming seasons can be presented so that the risks of drought and wet years can be managed.