The purpose of this paper is to provide an overview of paleoceanography and
paleoclimatology as a framework for other papers dealing with The Earth Sy
stem: Geochemical Perspectives. An introduction to both paleoceanography an
d paleoclimatology is followed by examples of the temporal changes through
the Phanerozoic. The important and interactive role of the biosphere is emp
hasized. Many important changes in the Earth system have affected the coupl
ed ocean-atmosphere system and many, in turn, have been reflected in biotic
events. Many such changes can be tracked through time using geochemical si
gnatures as proxy indicators. Whereas the scale of past paleoceanographic a
nd paleoclimatic changes have been generally appreciated for some time, the
recognition of periodic rapid change in the ocean/climate state and the ab
ility to study and measure these precisely is only a recent accomplishment.
The potential for such rapid change in the ocean/climate/biosphere of the
Earth system raises concerns for events in the near future that may be forc
ed by anthropogenic activities that enhance natural variability. (C) 1999 E
lsevier Science B.V. All rights