Olsen, Paul E. and Johansson, Annika K., (Lamont-Doherty Earth
Observatory of Columbia University, Palisades, New York) To a
first approximation, the transitions between major global
climate states (i.e. "ice house" vs. "hot house") do not seem to
correlate with the largest scale aspects of tectonic history.
Ice house conditions came and went during the existence of
Pangea during the late Paleozoic while hot house conditions were
maintained during the last stages of Pangea, its breakup and its
dispersion during the Mesozoic. Hot house conditions gave way to
ice house conditions during the Cenozoic during which the
continents remained more or less dispersed. In contrast, there
is a good correlation between major climate states and the
staggered evolution of producing and consuming organisms.
Terrestrial plants tend to increase chemical weathering (via
root respiration and decay) while herbivores and detritivores
tend to suppress chemical weathering (via lowering of root
productivity and subsurface decay). Othe