Ozone layer deflation

Groundbreaking research in the s and s revealed signs of trouble.

Click to open interactive version When is the ozone layer expected to recover? Consumption fell by more than 60 percent by ; 80 percent by ; and by percent by How much of an impact will recent emissions of CFC have on ozone layer recovery?

Dijk et al. Antarctic ozone hole[ edit ] The discovery of the Antarctic "ozone hole" by British Antarctic Survey scientists FarmanGardiner and Shanklin first reported in a paper in Nature in May [98] came as a shock to the scientific community, because the observed decline in polar ozone was far larger than anyone had anticipated.

In correlating chemical pollution tracers and CFC emissions, the authors suggest there is strong evidence that the source of increased CFC emissions is Eastern Asia. The blue area therefore represents the estimated quantity of GHG or radiative forcing averted as a result of the Montreal Protocol.

Essay on ozone layer depletion and protection

This means that despite reductions in ODS emissions and eventually complete phase-out of these substances , equivalent stratospheric chlorine ESC concentrations are expected to remain higher than levels through to the end of the century. This means HFC emissions have increased notably in recent years. Fear of ozone depletion was abated until when Sherwood Rowland and Mario Molina discovered that chlorofluorocarbons could be photolyzed by high energy photons in the stratosphere. Ozone depletion and the subsequent increase in UV-B irradiation, as discussed above , can increase negative health impacts such as skin cancer , and other implications such as sunburn and skin ageing. These complex chemistry transport models e. Americans voluntarily switched away from aerosol sprays before legislation was enforced, while climate change failed to achieve comparable concern and public action. With a GWP up to 10, times higher than carbon dioxide CO2 , these gases can have a notable impact on total greenhouse gas emissions, even in very small concentrations. They are projected to reach pre levels before

Stratospheric ozone is that which is present in the upper atmosphere the stratosphere; typically extending from around 10 to 15km up to 50km depending on latitude.

Short-wavelength UV radiation splits an oxygen O 2 molecule into two oxygen O atoms, which then combine with other oxygen molecules to form ozone. Shown in the chart below is the level of natural emissions which has been approximately consistent over this periodand total emissions which is the sum of natural and man-made emissions.

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