High-resolution climate records of the past 2,400 years from the offshore of northernmost California and central Oregon

High resolution diatom and pollen data from piston core TN062 0550 off northernmost California, and Kasten core WW7710A-26 off coastal Oregon, are compiled for the past 2,400 years. Diatom proxy data for Fall SST from both cores record warm SST's in the intervals from ca. AD 400 to 600, and from ca. AD 1050 to 1300 (later part of the Medieval Warm Period). The intervening AD 650 to 1000 interval, and the post-AD 1350 interval at both sites appear to be relatively cool. Whereas the pollen assemblage from TN062 0550 is dominated by coastal redwood, the pollen assemblage from WW7710A-26 displays alternating moist-dry cycles of alder vs. pine, as well as cycles of western hemlock (typical of the coastal forests of Oregon) vs. coastal redwood (typical of the coastal forests of northern California). Coincidence of intervals characterized by warmer diatom SST with drier pollen assemblages, and those of cooler diatom SST with moister pollen assemblages in the coastal Oregon core, recall the modern-day association of cool PDO with increased precipitation, and warm PDO with decreased precipitation, in the Pacific Northwest.