Sea surface and high-latitude temperature sensitivity to radiative forcing of climate over several glacial cycles

TLDR: In this paper, a compilation of global sea surface temperature (SST) records that span around one glacial cycle or more is compared with changes in the earth's radiative balance over the last 520 000 years, as determined from greenhouse gas concentrations, albedo changes related to ice sheet area and atmospheric dust fluctuations.

Abstract: AbstractA compilation is presented of global sea surface temperature (SST) records that span around one glacial cycle or more, and it is compared with changes in the earth’s radiative balance over the last 520 000 years, as determined from greenhouse gas concentrations, albedo changes related to ice sheet area and atmospheric dust fluctuations, and insolation changes. A first scenario uses global mean values for the radiative changes, and a second scenario uses zonal means for 10° latitude bands for a more regionally specific perspective. On the orbital time scales studied here, a smooth increase of SST response from the equator to high latitudes is found when comparison is made to global mean radiative forcing, but a sharply “stepped” increase at 20°–30° latitude when comparing with the more regionally specific forcings. The mean global SST sensitivities to radiative change are within similar limits for both scenarios, around 0.8 ± 0.4°C (W m−2)−1. Combined with previous estimates of 1.3–1.5 times strong...