Thinning of Ozone has altered ocean circulation: Study

As per a latest study, a hole in the Antarctic ozone layer has changed the way waters in the southern oceans mix, which researchers say could impact global climate change. As per scientists this phenomenon has the potential to alter the amount of CO2 in the atmosphere. It has been found that subtropical intermediate waters in the southern oceans have become "younger" as the upwelling, circumpolar waters have gotten "older" – changes that are consistent with the fact that surface winds have strengthened as the ozone layer has thinned.

How is it important? How did the researchers found this?

How is it important?

This is significant as southern oceans play a crucial role in the absorption of heat and carbon dioxide, so any alterations in southern ocean circulation have the potential to change the global climate.

How did the researchers found this?

Researchers compared the levels of "chlorofluorocarbon-12," or CFC-12 in the southern oceans in early 1990s to the mid-to-late 2000s.

It was in 1930s when CFC-12 was first produced commercially and its concentration in the atmosphere increased rapidly until the 1990s when it was phased out by the Montreal Protocol on substances that damage the ozone layer.

As it was known that concentrations of CFCs at the ocean surface rises in tandem with those in the atmosphere, scientists were able to infer that the higher the concentration of CFC-12 deeper in the ocean, the more recently those waters were at the surface and have mixed recently. The inferred age changes – "younger" in the subtropics, "older" nearer the South Pole – are consistent with the observed intensification of surface westerly winds, which have occurred primarily because of the Antarctic ozone hole, suggesting that stratospheric ozone depletion is the primary cause of the changes in ocean ventilation.

Month: Current Affairs - February, 2013

Category: Science & Technology Current Affairs