How much ozone layer is left

When temperatures high up in the atmosphere stratosphere start to rise in late Southern Hemisphere spring, ozone depletion slows, the polar vortex weakens and finally breaks down, and by the end of December ozone levels have returned to normal.

Skip to main content. Tags: Ozone. Published 6 October Share this page. Climate change increases threats in South West Pacific. What is trending Climate change. Disaster risk reduction. Record-breaking ozone hole closes. Tags: Ozone. Published 6 January Strong Polar Vortex Ozone depletion is directly related to the temperature in the stratosphere, which is the layer of the atmosphere between around 10 km and round 50 km altitude.

Montreal Protocol The Montreal Protocol on Substances that Deplete the Ozone Layer is the landmark multilateral environmental agreement that regulates the production and consumption of nearly chemicals referred to as ozone depleting substances ODS. Share this page. Climate change increases threats in South West Pacific. What is trending Climate change. Disaster risk reduction. Each year for the past few decades during the Southern Hemisphere spring, chemical reactions involving chlorine and bromine cause ozone in the southern polar region to be destroyed rapidly and severely.

The area of the ozone hole is determined from a map of total column ozone. It is calculated from the area on the Earth that is enclosed by a line with a constant value of Dobson Units. The value of Dobson Units is chosen since total ozone values of less than Dobson Units were not found in the historic observations over Antarctica prior to Also, from direct measurements over Antarctica, a column ozone level of less than Dobson Units is a result of the ozone loss from chlorine and bromine compounds.

The graphs above show the progress of the ozone hole for The gray shading indicates the highest and lowest values measured since The red numbers are the maximum or minimum values. The stratospheric temperature and the amount of sunlight reaching the south polar region control the depth and size of the Antarctic ozone hole. The data for the ozone hole area , the minimum ozone , and the minimum stratospheric temperature are available. Also available is a table of values showing the maximum ozone hole area and the minimum ozone values for each year.

Click on the image to get a table of values.