Arctic salt clouds are reducting the impact of Global Climate Change on the Arctic region

Arctic salt clouds are reducting the impact of Global Climate Change on the Arctic region

Prior posts have noted both the various impacts of Global Climate Change ("GCC") on various aspects of the Earth and its atmospheric systems, as well as the failure of many/most models to include such impacts within their parameters. For example, a recent post noted that the solar cycle has probably resulted in GCC having less impact on temperatures than would otherwise be anticipated because the Sun is at a minimum in terms of its "11-year" cycle. Another such impact has been recently identified -- the impact of Arctic salt clouds.

Earth's warming in recent years has had an exaggerated impact in the Arctic, consistent with most predictions. There, temperatures have soared relative to temperate areas, resulting in an increased summer melting of sea ice. But new research indicates that the local warming would be even more dramatic if it were not for salt sprays kicked up by whitecaps from the Arctic's increasingly open waters. Snow and sea ice reflect much of the Sun's rays back into space. As an increasing share of the Arctic Ocean's year-round cover of sea ice has disappeared, the sea surface has darkened (reduced its albedo), absorbing more solar energy. In contrast, clouds deflect incoming solar rays; researchers have noted that some of the salt from sea spray could enter the lower atmosphere, forming diffuse filtering clouds of tiny particles. The question, thus, has been how effectively these clouds might offset warming due to the Arctic Ocean's diminishing summer albedo.

The majority of sea-salt particles emitted into the air are well under a micrometer in diameter. These tiny particles (aerosols) can persist in the atmosphere for days or even weeks, and apparently can rise to altitudes of a kilometer or more. Calculations suggest that the effect is roughly 10% of the albedo warming impact from reduced ice and snow; thus, the impact is small, but not insignificant.

The report on this study can be found at http://www.atmos-chem-phys.net/11/3459/2011/acp-11-3459-2011.html.