Evaluating the effect of simultaneous occurrence of Quasi-Biennial Oscillation phases with North Atlantic Oscillation and Arctic Oscillation phases on Iran's winter temperature

Fluctuations in temperature are more or less influenced by teleconnections. The aim of this study is to investigate the simultaneous role of the North Atlantic Oscillation and the Arctic Oscillation with Quasi-Biennial Oscillation on the winter season temperature in Iran. For this purpose, the temperature data of 100 meteorological stations were used in the statistical period of 1988-2019. Correlation coefficients between QBO, NAO, and AO teleconnections data were calculated with monthly temperature. Then the possible states for the simultaneous occurrence of the teleconnection patterns were determined and the temperature anomaly for the determined states was analyzed by drawing a diagram and a map in the GIS environment. The results showed that there is an inverse and significant correlation between the positive QBO phases and February temperature in most of the northern and western regions, so the highest correlation coefficient was calculated at Ilam station as -0.81. An inverse and significant correlation was observed between NAO and especially AO cycles with northern and western half temperatures, especially in January and February. The simultaneous occurrence of the negative (positive) phases of NAO and AO with the negative (positive) phases of QBO causes the occurrence of higher than normal (normal and lower than normal) temperatures in the western (eastern) half so that the warmest winters of the statistical period happened during the simultaneous occurrence of negative NAO, AO, and QBO phases. On the other hand, the simultaneous occurrence of neutral QBO phases with positive NAO and AO phases causes normal and lower-than-normal temperatures in most regions except the southern and southeastern parts of Iran, contrary to this situation, the simultaneity of QBO neutral phases with NAO and AO negative phases has caused the absence of severe temperature anomalies and the possibility of higher than normal temperatures with high intensity is unlikely.