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This study investigates and detects links between the precipitation characteristics with meteorological systems and teleconnections around the Urucuia Aquifer System (UAS). Several studies show the influence of meteorological systems and teleconnections on the volume and intensity of precipitation in South America, mainly the Atlantic Multidecadal Oscillation (AMO), the El Niño South Oscillation (ENSO), and the Pacific Decadal Oscillations (PDO). Then, the precipitation series’ statistical characterization impacted the aquifer system’s recharge from 1973 to 2006. Monthly and annual series were analyzed and tested the correlation analysis with the indexes of the AMO, PDO, and ENSO. Finally, the series of maximum daily rainfall on the UAS was determined, and the 15 largest events were chosen to analyze the retroactive trajectories of air masses and thus try to estimate which atmospheric systems was acting and their origin. It concluded that the total annual precipitation data indicated a decreasing linear trend and that external climatic phenomena can influence precipitation characteristics. The correlation with the AMO index revealed a potential teleconectivity between climate circulation patterns with average annual precipitation over the UAS (p-value ≤ 0.03). Moreover, the analysing of precipitation trajectories observed a greater amount of specific humidity in the atmosphere during the AMO negative period concerning the AMO positive period. Also, the negative AMO phase’s trajectories had higher latitudes closer to the Intertropical Convergence Zone, as opposed to the positive AMO phase, where the trajectory altitudes were lower and closer to the Capricorn tropic. |
