Associations between δ18O of water and climate parameters in a simulation of atmospheric circulation for 1979-95

Abstract

The Melbourne University spectral atmospheric general circulation model is adapted to include prediction of stable water isotopes. The new scheme performs well when the modeled δ18O of precipitation is compared to both monthly observations from a global network and high-frequency measurements from two neighboring southern Australian sites. The associations between the modeled isotopic signal, temperature, and precipitation are examined on a variety of timescales by exploring the spatial distribution of temporal partial correlations. In contrast to the view commonly taken in paleoclimate studies, typically less than 20% of δ18O variance can be explained by temperature changes. The association..