An evaluation of global warming and its impact

Abstract

Energy balance model has been calculated to assess the magnitude of the average global warming by the middle of the next century. It is shown that an increase in temperatures by about 4 K by the year 2050 as compared to the pre-industrial era (˜1800 AD) could result from the projected growth of atmospheric concentrations of major greenhouse gases i.e. carbon dioxide, methane, nitrous oxide and chlorofluorocarbons (CFCs). The changes in global warming are considered for different scenarios including the proposed regulatory measures on' the use of CFCs. It is shown that even though the adoption of the revised Montreal Protocol will reduce the global warming due to CFCs by almost 50%, the projected overall global rise in temperature will still be about 2.7 K by the year 2050. The possible climatic impacts of the global warming on a few biogeophysical parameters are found to be alarming. Unless prompt action is taken to control the emission fluxes of other major greenhouse gases on lines similar to CFCs, the consequences may be severe for life on earth.