• sea ice;   • Arctic amplification  [1] Atmospheric climate
models are subjected to the observed sea ice conditions during
2007 to estimate the regionality, seasonality, and vertical
pattern of temperature responses to recent Arctic sea ice loss.
It is shown that anomalous sea ice conditions accounted for
virtually all of the estimated Arctic amplification in surface-
based warming over the Arctic Ocean, and furthermore they
accounted for a large fraction of Arctic amplification occurring
over the high-latitude land between 60°N and the Arctic Ocean.
Sea ice loss did not appreciably contribute to observed 2007
land temperature warmth equatorward of 60°N. Likewise, the
observed warming of the free atmosphere attributable to sea ice
loss is confined to Arctic latitudes, and is vertically confined
to the lowest 1000 m. The results further highlight a strong
seasonality of the temperature response to the 2007 sea ice
loss. A weak signal of Arctic amplification in surface based
warming is found during boreal summe