ESA’s Envisat Measures Record Ozone Loss over Arctic
06.04.2011 - Atmosphere & Space, Arctic
ESA’s Envisat satellite recorded record ozone depletion over the Arctic during March. The record low, researchers say, was caused by unusually strong winds, better known as the “polar vortex”. The “polar vortex” isolated the atmospheric mass over the North Pole and prevented it from mixing with air in the mid-latitudes, which led to very low temperatures.
When the warmer temperatures of March hit this cold air mass, chlorine and bromine – both ozone-depleting gases originating from chlorofluorocarbons (CFCs) – were released. These gases then broke ozone molecules (O3) down into diatomic oxygen molecules (O2) in the lower stratosphere, 20 km from the Earth’s surface.
Scientists are now trying to find out why the 2011 and 1997 Arctic winters were so cold, and whether they were related to climate change. However for this, additional research on ozone modelling and ozone trend monitoring is needed. For this research, the measurements from Envisat are crucial, as they enable scientists to separate chemical and dynamical changes and identify the influence of climate change on the stratosphere.
