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This one simple mathematical trick can accurately predict the shape and melting effects of ponds on Arctic sea ice, according to new research. The study should help climate scientists improve models of climate change and perhaps plug a gap between scientific predictions and observations over the past decade.
Every winter, some of the ocean freezes into ice. Much of the Arctic ecosystem -- from polar bears to algae -- revolves around this sea ice. It also has a significant impact on the global climate; it can reflect heat back out to space so the Earth doesn't absorb it, and it's a major player in ocean circulation. One possibility is melt ponds. As the sun shines and the ice melts, ponds of water form atop the ice. These ponds absorb extra sunlight, because they're darker than ice, which in turn causes the rest of the ice to melt faster. Their size and shape also influence how ice breaks up, and how much light gets to organisms living below the ice. The researchers wondered if there was a better way to statistically model these ponds. Their "void" method starts by creating a series of random circles, allowing them to overlap and considering the voids between the circles as melt ponds. This turns out to be quite effective at estimating how actual melt ponds form and behave, which they found by comparing them to aerial images of melts taken in 1998 and 2005. Simpler math is particularly helpful for scientists trying to build global climate models, which are already massively complicated and computationally expensive.Image credit: Healy–Oden Trans-Arctic Expedition (2005)
