Campus carbon neutrality one country has not used up all of its allotted emissions, it can sell them to other countries that have gone over their limit. The Montreal Protocol on Substances that Deplete the Ozone Layer is an international agreement that seeks to phase out chemicals that damage the ozone layer. The Montreal protocol was signed in 1987, went into practice in 1989, and was further amended in London in 1990 and in Copenhagen in 1992. The protocol set a quicker timetable for industrialized nations to phase out chemicals than it did for developing nations. For example, developed countries were to phase-out
Montreal Protocol Antarctic Survey scientists Joe Farman, Brian Gardiner and Jonathan Shanklin published results of abnormally low ozone concentrations above Halley Bay near the South Pole. They speculated that this was connected to increased levels of CFCs in the atmosphere. It took several other attempts to establish the Antarctic losses as real and significant, especially after NASA had retrieved matching data from its satellite recordings. The impact of these studies, the metaphor 'ozone hole', and the colourful visual representation in a time lapse animation proved shocking enough for negotiators in Montreal, Canada to take the issue seriously. Also in 1985, 20 nations,