PRISM3 DOT1 (Pliocene Research, Interpretation and Synoptic Mapping 3, Deep Ocean Temperature 1) provides a three-dimensional temperature reconstruction for the mid-Pliocene Atlantic Basin, the first of several regional data sets that will comprise a global mid-Pliocene reconstruction. DOT1 is an alteration of modern temperature values for the Atlantic Ocean in 4 degrees X 5 degrees cells in 13 depth layers for December 1 based on Mg/Ca-derived BWT estimates from seventeen DSDP and ODP Sites and SST estimates from the PRISM2 reconstruction (Dowsett and others, 1999). DOT1 reflects a vaguely modern circulation system, assuming similar processes of deep-water formation; however, North Atlantic Deep Water (NADW) production is increased, and Antarctic Bottom Water (AABW) production is decreased. Pliocene NADW was approximately 2 degrees C warmer than modern temperatures, and Pliocene AABW was approximately 0.3 degrees C warmer than modern temperatures.