Principal Investigator Edward Boyle
Almost all of the lead in the ocean derives from human emissions from high temperature industrial activities (smelting, coal combustion, incineration, etc.) and leaded gasoline utilization. Most of this lead was emitted in the past 100 years with peak U.S. emissions in the 1970's. A large fraction of this Pb is attached to fine particles and moves with the global atmospheric circulation before being deposited in remote regions. Boyle’s group has been studying this "global geophysical experiment" by following the evolution of Pb in ice cores and in the ocean. By measuring Pb in surface and deep seawater samples for the past 20 years, they can estimate Pb for the preceding century using Pb in annually-banded corals.