Tracking the water fingerprints of Cocos Island: a stable isotope analysis of precipitation, surface water, and groundwater

摘要: The use of stable isotopes water, both δ 2 H and 18 O has provided novel insights in hydrological studies, ecological applications, understanding climate variability, reconstructing paleoclimate. However, information on the isotope composition water tropical marine island environments is normally scarce within Central America Isthmus. Here, we present first isotopic characterization precipitation, surface groundwater at Cocos Island, Costa Rica eastern Pacific Ocean region. Our results show that Island MWL can be described as: H=8.39· O+13.3; r =0.98 (n=29). Dry season rainfall events ranged from -4.9 ‰ up to -2.4 with a mean d- excess 13.2 ‰. By beginning May, Intertropical Convergence Zone reaches resulting notable depletion ratios (up -10.4 -76.2 H). During wet season, averaged -6.1 -38.5 9.9 HYSPLIT air mass back trajectories indicate strong influence origin precipitation two main moisture transport mechanisms, northeasterly (January-May) southwesterly (May-November) trade winds. Small seasonal variations were observed throughout year values ranging -3.9 (dry n=19) -4.8 (wet n=13). Groundwater samples exhibited similar trend more depleted during (-5.2 -29.8 Overall, measured meteoric serves better delineate contribution towards It also provides valuable reference discriminate orographic distillation Caribbean enriched inputs continental studies.