The Younger Dryas (YD) is well expressed in many North Atlantic records, revealing evidence for a reduction in the Atlantic meridional overturning circulation, basin-wide cooling, and changes in the atmospheric and marine radiocarbon inventories. Few records have examined the Pacific response to this time period in great detail however, allowing for potential biases in our understanding of the forcing mechanisms, as well as the timing and pathways of climate reorganization. Here we examine a marine sediment core (EW0408 66JC) from the Gulf of Alaska (GOA) (426m depth) with a greatly expanded YD section (8m), giving us a rare opportunity to examine the Pacific response to these abrupt climate transitions with sub-decadal resolution. Results indicate strong correlations between oxygen isotope records of Greenland and GOA, suggesting a dominant role for the atmosphere in communicating climate between the Pacific and Atlantic basins. Using a constant marine reservoir correction, the YD onset in the GOA appears synchronous with the timing in Greenland and is accompanied by a rapid shift in oxygen and carbon isotopes, a decrease in surface water temperature (Mg/Ca), and a shift towards low oxygen conditions. By anchoring the GOA record to the Greenland chronology, it reveals changes in the marine reservoir age of ~400yrs during the end-Bolling-Allerod and YD/Holocene transitions. These changes in surface water radiocarbon are not consistent with changes in the atmospheric radiocarbon record, indicating that variations in upper water ventilation must have occurred at this site. However, the Benthic-Planktonic radiocarbon differences reveal relatively small differences during the YD and a large offset just proceeding the YD, the opposite of what might be expected based on the marine reservoir changes. These observations point to very complex changes occurring in ocean circulation and the distribution of radiocarbon in the North East Pacific during the YD transitions.