Eocene oceanic responses to orbital forcing on precessional time scales

The goal of our study was to gain an estimate of the variability of ocean-r elated climate processes driven by insolation forcing over a realistic prec essional cycle in an Eocene greenhouse world. Between endmembers of a prece ssional cycle mean annual sea surface temperatures (SSTs) vary by up to 5 d egreesC at high northern latitudes, with minimal tropical SST response. Ext ratropical regions of the Pacific, Atlantic, and Tethys Oceans show up to a two-fold variation in upwelling strength, while oceanic regions adjacent t o northwestern Africa, India, and South America exhibit little oceanic upwe lling variability. The response of ocean surface moisture balance to the fo rcing is greatest in the tropics, varying by as much as 60%. Continental ru noff varies by up to a factor of two in some regions. These results may be useful in identifying locations with maximum likelihood of future recovery of orbital cyclicity in deep-sea sediments.