Phys.org July 17, 2024
Sea ice cools Earth by reducing its absorbed solar energy. An international team of researchers (USA – University of Michigan, Finland) combined radiative transfer modeling with satellite-derived surface albedo, sea ice, and cloud distributions to quantify the top-of-atmosphere sea ice radiative effect (SIRE). The Arctic Sea ice radiative effect has weakened by about 24%, since 1980. The planetary cooling effects of Arctic and Antarctic Sea ice during 2016–2023 were about 20% and 12% less, respectively, than they were during 1980–1988. Arctic SIRE has weakened, implying a 21%–27% reduction in the reflective power of Arctic Sea ice since 1980. Antarctic sea ice exhibited a regime change in 2016, resulting in 2016–2023. Global sea ice has lost 13%–15% of its planetary cooling effect since the early/mid 1980s, and the implied global sea ice albedo feedback is 0.24–0.38 W m−2 K−1. Disappearing sea ice is therefore amplifying climate change by causing Earth to absorb roughly an additional 0.3 W m−2 of solar power for each degree Celsius of global warming, a feedback that is stronger than that simulated by most climate models… read more. Open Access TECHNICAL ARTICLE
Seasonal climatology during 1980–2023 of globally-averaged sea ice radiative effect… Credit: Geophysical Letters 17 July 2024