Premium
Sea surface temperature control on the stable isotopic composition of rainfall in Panama
Author(s) -
Lachniet Matthew S.
Publication year - 2009
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2008gl036625
Subject(s) - intertropical convergence zone , panama , sea surface temperature , climatology , environmental science , stable isotope ratio , oceanography , geology , precipitation , geography , meteorology , physics , quantum mechanics , ecology , biology
The climate dynamical controls on rainfall oxygen isotope values ( δ 18 O rain ) are poorly constrained in most areas. In Central America, rainfall variations are associated with sea surface temperature anomalies in the Pacific and Atlantic Oceans, yet the response in δ 18 O rain has not been adequately investigated. Analysis of a 30‐year time series of δ 18 O rain in Panama was used to test the hypothesis that δ 18 O rain variations are forced by anomalies in rainfall and sea surface temperatures (SSTAs) in the bordering tropical oceans. The results show that δ 18 O rain values in Panama are positively (negatively) correlated with SSTAs in the Pacific Ocean (Caribbean Sea). The data are consistent with a dominant 'amount effect' whereby lowest δ 18 O values are associated with a northerly position of the Intertropical Convergence Zone when regional rainfall is high. The source effect (Caribbean vs. Pacific), as constrained by wind direction, does not appear to be an important control on the temporal variations in δ 18 O rain .