A full sequence of brief interstadials (Dansgaard-Oeschger [D-O] cycles) are recorded from 60 to 25 ka in Santa Barbara basin, California, Ocean Drilling Program Hole 893A, by planktonic foraminiferal isotopic and assemblage changes at unparalleled high resolution for the oceans. Synchronous climatic response between north Pacific surface waters and the Greenland ice sheet during D-O cycling is strongly indicated by remarkable similarities in speed, magnitude, and character of rapid oceanic and atmospheric reorganizations. Inferred sea-surface temperature warmings of as much as 5 degrees C within a few decades, and brief warming overshoots of as much as 3 degrees C suggest involvement of an atmospheric amplification. Top-down, in situ atmospheric warming of the ocean is implied by differential responses (partial decoupling) in the changes recorded in surface and thermoclinal waters.