ESS101C
Prof.
Jin-Yi Yu
Possibility 1: Physical
Oceanographic Explanation of CO2 Changes
qChanges in the physical
oceanographic characteristics of the surface ocean – its temperature and salinity –
during glaciations might alter the chemical solubility of Co2.
qBecause
CO2 dissolves more readily in colder seawater, atmospheric CO2 will drop by 9 ppm for each 1°C of ocean
cooling.
qBecause CO2 dissolves more
easily in seawater
with a lower salinity, saltier glacial seawater will increase
atmospheric CO2 level.
qThe effects of seawater
temperature and salinity work against each other!
qThe net
effect of the physical oceanographic influences on atmospheric CO2 is to decrease CO2 by 11 ppm during
glaciations.
qThis process only explains 10%
of the CO2 changes on
orbital scales.
(from Earth’s Climate: Past and Future)