The Arctic is heating up more than four times faster than the rate of global warming. This trend has stepped upward steeply twice in the last 50 years, a finding missed by all but four of 39 climate models. Contributing causes are probably sea-ice and water-vapor feedbacks combined with changes in how atmospheric and oceanic heat move into the Arctic. Future increases in the Arctic amplification index are likely to be smaller as the temperature difference between the Arctic and the tropics decreases. Still, four times vs. the two times we’ve seen before is disconcerting.
Story Source: DOE/Los Alamos National Laboratory