Antarctica’s clouds are a big mystery to climate scientists
I know what you’re thinking: Clouds can’t possibly be that complicated, right? They’re just a bunch of water vapor hanging out in the atmosphere, and sometimes they leak.
Sure, there are a lot of variables at stake: temperature on land and at sea, wind speeds both local and global, humidity, pressure, not to mention a changing climate. And, yes, clouds are subject to chaotic physical forces such that even the most detailed measurements can’t explain what will happen more than a few hours into the future.
OK, that sounds pretty complicated. It turns out clouds are one of the big unknown factors when scientists try to build computer models of the climate. We just don’t know what they’re going to do as the atmosphere absorbs more and more heat — will they form differently? Might they buffer systematic changes by reflecting more heat or exacerbate them by failing to do so?
In places like West Antarctica, where the last careful observations of clouds were made in 1967, how clouds behave is an enduring and important mystery. The gigantic West Antarctic ice sheet may be collapsing as we speak, which could contribute a disastrous four feet to sea-level rise all on its own. How clouds slow or speed its melting will have a major, direct effect in the coming century.
Which is why scientists just launched the Atmospheric Radiation Measurement West Antarctic Radiation Experiment (AWARE — I know, I know, they used “radiation” twice, but scientists love a meta acronym). Here’s more on the project from Scientific American:
The US$5-million project, known as the Atmospheric Radiation Measurement West Antarctic Radiation Experiment (AWARE), began to observe the skies near McMurdo in November and will run until early 2017. A second measurement station, 1,600 kilometres away in the ice sheet’s interior, will operate until the end of this month. (The site is so remote that it can be used only during the Antarctic summer.) […]
AWARE, which is led by Scripps atmospheric scientist Dan Lubin, aims to get the best data yet on clouds and aerosol particles above West Antarctica. That includes mixedphase clouds, which occur in polar regions and combine supercooled water with ice. Studies have shown that clouds moving across Antarctica’s interior are mostly ice, whereas those moving onshore from the coast contain more liquid water. The composition of these clouds plays a major part in determining how much sunlight they reflect into space—which helps to shape atmospheric circulation and weather patterns below.
These icy-watery clouds over Antarctica could affect life in the tropics and elsewhere, which is about as complicated as it gets. See, aren’t you glad you’re … aware?