global change biology

Major issues of global environmental change are global warming and ozone depletion. The need of the hour is to stabilise the atmospheric concentrations of green house gases. It can be achieved only when all the countries join hand in lowering the global emission of green house gases from their present levels.1. Montreal Protocol. On 16th September, 1987, twenty seven industrialized countries signed an agreement to limit the production and use of ozone-depleting substances (ODS) e.g. chlorofluorocarbons, phasing out of ODS, and also to help the developing countries to implement use of alternatives to CFCs. In May, 1989 Montreal Protocol was ratified by 82 nations at Helsinki (Helsinki Declaration). 175 countries have signed this protocol till date.2. Earth Summit. United Nations Conference on Environment and Development was held in Rio-de-Janerio, Brazil in 1992. It is popularly known as Earth Summit. In this conference, recommendations of CCC (Convention on Climate Change) were signed by 154 nations. A general agreement was reached to maintain emissions of green house gases at 1990 level.3. Kyoto Protocol. A follow up international conference was held in December, 1997 in Kyoto, Japan. In this conference, an agreement was signed by different countries to mitigate global environmental change by taking appropriate measures to reduce emissions of green house gases at a level 5% below the 1990 level by 2008 A.D. to 2012 A.D.