Amplification Amplifying mechanisms Feedbacks associated with sea ice and snow cover are widely cited as the main cause of recent terrestrial polar amplification. These  are particularly noted in local polar amplification . However , large-scale amplification is also observed in model worlds with no ice or snow. It appears to arise both from a (possibly transient) intensification of poleward heat transport and more directly from changes in the local net radiation balance ( an overall decrease in outward radiation will produce a larger relative increase in net radiation near the poles than near the equator ). Particularly, polar amplification can be attributed to largely by outgoing longwave radiation. This feedback has proven to be just as important, and efficient, as the ice-albedo feedback. Radiation feedback is connected to temperature gradients between the equator and the poles interacting with heat transportation poleward . Some examples of climate system feedbacks thought to contribute to recent polar amplification include the reduction of snow cover and sea ice, changes in atmospheric and ocean circulation, the presence of anthropogenic soot in the Arctic environment, and increases in cloud cover and water vapor. CO2 forcing has also been attributed to polar amplification. Most studies connect sea ice changes to polar amplification. Both ice extent and thickness impact polar amplification. Larger ice extent leads to higher polar amplification, as does thinner ice coverage . Some models of modern climate exhibit Arctic amplification without changes in snow and ice cover.
Amplification Amplifying mechanisms Feedbacks associated with sea ice and snow cover are widely cited as one of the principal causes of recent terrestrial polar amplification. These feedbacks are particularly noted in local polar amplification , although recent work has shown that the lapse rate feedback is likely equally important to the ice-albedo feedback for Arctic amplification. Supporting this idea , large-scale amplification is also observed in model worlds with no ice or snow. It appears to arise both from a (possibly transient) intensification of poleward heat transport and more directly from changes in the local net radiation balance . Local radiation balance is crucial because an overall decrease in outgoing longwave radiation will produce a larger relative increase in net radiation near the poles than near the equator . Thus, between the lapse rate feedback and changes in the local radiation balance, much of polar amplification can be attributed to changes in outgoing longwave radiation. This is especially true for the Arctic, whereas the elevated terrain in Antarctica limits the influence of the lapse rate feedback . Some examples of climate system feedbacks thought to contribute to recent polar amplification include the reduction of snow cover and sea ice, changes in atmospheric and ocean circulation, the presence of anthropogenic soot in the Arctic environment, and increases in cloud cover and water vapor. CO2 forcing has also been attributed to polar amplification. Most studies connect sea ice changes to polar amplification. Both ice extent and thickness impact polar amplification. Climate models with smaller baseline sea ice extent and thinner sea ice coverage exhibit stronger polar amplification . Some models of modern climate exhibit Arctic amplification without changes in snow and ice cover.
R
the main cause
one of the principal causes
A
feedbacks
R
. However
, although recent work has shown that the lapse rate feedback is likely equally important to the ice-albedo feedback for Arctic amplification. Supporting this idea
R
(
. Local radiation balance is crucial because
R
outward
outgoing longwave
R
). Particularly,
. Thus, between the lapse rate feedback and changes in the local radiation balance, much of
R
largely by
changes in
R
feedback has proven to be just as important, and efficient, as the ice-albedo feedback. Radiation feedback is connected to temperature gradients between the equator and the poles interacting with heat transportation poleward
is especially true for the Arctic, whereas the elevated terrain in Antarctica limits the influence of the lapse rate feedback
R
Larger ice extent leads to higher polar amplification, as does thinner ice coverage
Climate models with smaller baseline sea ice extent and thinner sea ice coverage exhibit stronger polar amplification