Featured Image: Church Militant
By: Alice Morris
A recent study out of the University of Washington and the Massachusetts Institute of Technology reveals that the unique currents of the Southern Ocean may be protecting the waters surrounding Antarctica from the effects of global warming.
The study, which was published May 30th in Nature Geoscience, uses data from free-drifting observational floats and model simulations of global seawater movements to explain this phenomenon.
According to the study, the strong westerly winds around Antarctica push surface waters north, away from the continent, which in turn pulls cold water up from the depths of the Southern Ocean. This water travels several thousands of meters to reach the ocean’s surface and it predates the machine age, meaning it hasn’t been subjected to modern climate change.
Image Credit: K. Armour / UW
Meanwhile, waters in the rest of the world’s oceans make a much shorter trip to the ocean’s surface – a few hundred meters at most – which doesn’t have the same cooling effect.
As a result, the seawater that’s experienced the most modern climate change pools around the North pole, warming it significantly, while Antarctica remains largely indifferent to any global warming trends.
Previously, scientists believed that the delayed warming around the South Pole was a result of the frigid southern seas churning and pushing heat down into the depths of the ocean instead of northward towards the Arctic.
This new research is especially important because it combats the theory that unchanging temperatures in the Antarctic disprove human-driven climate change, a position held by many global warming deniers.
Image Credit: Getty Images via Huffington Post
Theoretically, we could expect that increased CO2 levels would lead to similar warming at both the North and South Poles. However, as this study demonstrates, we can’t directly compare the warming trends at the two poles because the ocean circulation associated with each is so different.
Using the findings from this study, scientists are better able to track where the earth’s extra heat goes when trapped by greenhouse gases, allowing them to predict changing temperatures in the future with greater accuracy.
The findings also prompt scientists to move away from a definition of global warming that implies similar warming trends around the world, and towards a greater investigation of ‘regional patterns of warming,’ that take into account the various ocean currents around the globe.
Read more about the interesting new study here.