First, most climate simulations, including ours above and those of IPCC [1], do not include slow feedbacks such as reduction
of ice sheet size with global warming or release of greenhouse gases from thawing tundra.
The standard climate sensitivity and climate model do not in - clude effects of «slow» climate feedbacks such as change
in ice sheet size.
DO NOT INCLUDE SLOW FEEDBACKS such as reduction of
ice sheet size with global warming or release of greenhouse gases from thawing tundra.
It is easy to see why this feedback amplifies the climate change, because reduction of
ice sheet size due to warming exposes a darker surface, which absorbs more sunlight, thus causing more warming.
I consider a rapid > 50 % increase in
Antarctic ice sheet size while CO2 is higher than current day something of merit and not to be dismissed lightly.
In addition there are slow climate feedbacks, such as changes of
ice sheet size, that occur mainly over centuries and millennia.
In addition there are slow climate feedbacks, such as changes of
ice sheet size, that occur mainly over centuries and millennia.
However, for the sake of analysis, we can also choose and compare periods that are in quasi-equilibrium, periods during which there was little change of
the ice sheet size or the GHG amount.
«Third, in a period when ocean basins were similar to modern, ice age climate sensitivity to pCO2 changes is underestimated by climate models even when long term changes in solar forcing and
ice sheet size and distribution are taken into account, implying that internal positive feedbacks are stronger than previously thought.»