Responses of polar energy budget to regional SST changes in extra-polar regions

Abstract. Surface temperature at polar regions is not only affected by local forcings and feedbacks, but also depends on teleconnections between polar regions and low latitude regions. In this study, the responses of energy budget in polar regions to remote SST changes are analysed using a set of idealized SST patch experiments. The results show that responses of polar energy budget to remote sea surface warmings are regulated by changes in atmospheric energy transport, and radiative feedbacks also contribute to the polar energy budget at both the top-of-atmosphere (TOA) and surface. An increase of poleward atmospheric energy transport to polar regions results in an increase of surface and air temperature, leading to a radiative warming at surface and radiative cooling at TOA. In response to sea surface warmings in most midlatitude regions, the poleward atmospheric energy transport to polar regions in the corresponding hemisphere increases. Sea surface warming over most tropical regions enhances the polar energy transport to both Arctic and Antarctic regions, except that an increase in the Indian Ocean's temperature results in a decrease in poleward atmospheric energy transport to the Arctics due to different responses of stationary waves. Sensitivity of Arctic energy budget to tropical SST changes is generally stronger than that of Antarctic energy budget, and poleward atmospheric heat transport is dominated by dry static energy, with a lesser contribution from latent heat transport. Polar energy budget is not sensitive to SST changes in most subtropical regions.