Abstract
Temporary changes in precipitation may lead to sustained and severe drought or massive floods in different parts of the world. Knowing the variation in precipitation can effectively help the water resources decision-makers in water resources management. Large-scale circulation drivers have a considerable impact on precipitation in different parts of the world. In this research, the impact of El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO) on seasonal precipitation over Iran was investigated. For this purpose, 103 synoptic stations with at least 30 years of data were utilized. The Spearman correlation coefficient between the indices in the previous 12 months with seasonal precipitation was calculated, and the meaningful correlations were extracted. Then, the month in which each of these indices has the highest correlation with seasonal precipitation was determined. Finally, the overall amount of increase or decrease in seasonal precipitation due to each of these indices was calculated. Results indicate the Southern Oscillation Index (SOI), NAO, and PDO have the most impact on seasonal precipitation, respectively. Additionally, these indices have the highest impact on the precipitation in winter, autumn, spring, and summer, respectively. SOI has a diverse impact on winter precipitation compared to the PDO and NAO, while in the other seasons, each index has its special impact on seasonal precipitation. Generally, all indices in different phases may decrease the seasonal precipitation up to 100%. However, the seasonal precipitation may increase more than 100% in different seasons due to the impact of these indices. The results of this study can be used effectively in water resources management and especially in dam operation.
Highlights
The role of climate in human life and other organisms is crucial
At α = 0.05, Southern Oscillation Index (SOI), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO) have a significant relationship with winter precipitation in 72, 53, and 51 stations, respectively, while they have a significant relationship with spring precipitation in 74, 16, and 51 stations, respectively
Just 30, 25, and 47 stations had a meaningful correlation with SOI, PDO, and NAO, respectively
Summary
Any seasonal and periodic fluctuations in the climate of an area can seriously affect living conditions. These fluctuations in arid and semi-arid regions of the world have more significant impacts [1,2,3]. Iran is located in an arid and semi-arid region with less than a third of the world average precipitation, which reflects thelimited water resources in this country [4,5]. The precipitation varies significantly between the years, which makes a challenge for water resources management. While long-term exact precipitation forecasting is difficult, information about the increase or decrease in precipitation can help the water resources policymakers. The El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO) are distinguished as the most essential phenomena due to theirconsiderable impacts on hydro-climatic systems
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
