Late Pliocene (~2.6-3.4 million years ago) multiproxy paleoceanographic datasets from Ocean Drilling Program subpolar North Pacific Leg 145 sites 883 (51.12°N, 167.46°E, 2384 m water depth) and 887 (54.22°N, 148.27°W, 3631.2 m water depth). Composite splice for site 883 was created by visual correlation of the shipboard gamma ray attenuation and porosity evaluator (GRAPE) wet bulk density (WBD) measurements between 883B and 883C starting at core 9H and ending at 18H. An astronomically tuned age model for site 883 was developed by correlation of benthic foraminiferal δ18O (3.0–3.385 Ma) to the δ18O probabilistic stack and the 883 GRAPE WBD composite (2.841–3.0 Ma & 3.385–3.465 Ma) to the nearby astronomically-tuned ODP 882 carbonate weight percent record. Benthic foraminiferal stable oxygen and carbon isotope ratios were quantified with a Finnigan Mat 252 with Carbonate Kiel III autosampler. Alkenone concentrations and the UK'37 sea surface temperature index were determined by an Agilent Technologies 6890 gas chromatograph flame ionization detector (GC-FID), with an Agilent Technologies DB-1 column (60 m, 0.32 mm diameter, 0.10 mm film thickness). Calcium carbonate content was determined by acidification of bulk sediment samples with 2M hydrogen sulfide and quantification of the resulting gaseous carbon with a UIC Coulometrics CO2 Coulometer. A composite section was developed for ODP 887 by correlation of shipboard gamma ray attenuation and porosity evalvuator (GRAPE) wet bulk density between 887A and 887C. An improved age model was developed by correlation of the GRAPE composite to that of ODP 883. Stable carbon isotope data were compiled for each marine isotope stage of the mid-Piacenzian warm period from 23 IODP/ODP/DSDP core sites. These data were then binned by marine isotope stage, averaged, and grouped by ocean basin.