INVITED: MIDDLE PLIOCENE DEEP OCEAN TEMPERATURE

Deep ocean temperature is a vital parameter for understanding the character and causes of past climate change. For example, deep ocean temperature can serve as an indicator of, and potentially plays a role in, changes in ocean circulation; it can be used in conjunction with benthic marine oxygen isotopes to provide records of the oxygen isotopic composition of seawater thereby providing a means to constrain past changes in continental ice volume and/or changes in ocean salinity; it can provide estimates of high latitude surface ocean conditions; and it represents an important parameter for initializing climate simulations. Despite its importance, little is known about deep ocean temperatures during the middle Pliocene. Middle Pliocene deep ocean temperature data for the North and South Atlantic, based on Mg/Ca ratios of ostracodes from ~15 Ocean Drilling Program sites, will be presented and considered in the context of hypotheses for the possible cause of middle Pliocene warming.