Evaluation of Relationship between Oscillations of Selected North Hemisphere's Teleconnection Indices with Evapotranspiration Variations in Southern Section of Aras River Basin

Due to the Earthchr('39')s climate is systemic, the Large-scale atmospheric patterns, are considered as one of the most important factors that affects the climate in different regions of the world. This issue indicates necessity of investigating these patterns and their effects on climate areas beyond a given region. In this study, the relationship between North Hemispherechr('39')s teleconnection indices and Evapotranspiration (ET) at synoptic stations in south of the Aras River basin during the 26-years statistical period (1992-2017) was investigated.  Run test was used to evaluate the sequence and homogeneity of data. Pearson correlation coefficient was used to assess the relationship status between these patterns and the changes in the studied variable. The highest significant correlation coefficient calculated between ET stations and some patterns was obtained with non-delayed mode, with 1, 2 and 3-months delay which are weak in terms of intensity.While in different, the highest significant correlation coefficients was observed that it was Calculated at Ahar station (in winter, spring and autumn seasons with EA, SCA, NAO and EA indices, respectively, amount 0.79*, -0.53**, -0.49** and -0.43*), at Ardabil (in spring with SCA, in summer and autumn with POL (-0.54**, 0.44* and -0.56**) and at Parsabad (in autumn with EP/NP 0.46*). Significant correlation between phases of EA, EA/WR and EP/NP, SCA positive phase and PNA negative phase with Z-Scores of some stationchr('39')s was observed low to moderate intensity at the confidence level of 0.95 and above. The results  of the backward regression model, in addition to introducing the most effective  indices in the modeling of stationchr('39')s ET, showed that  they do not have the explain this variable in Aras basin.