Global Warming and Its Impact on Our Ecosystem

Pages:74-79
Rachana Shalini (P.G. Department of Botany, L. N. Mithila University, Darbhanga)

The phrase “global Warming” refers to the documented historical warming of the earth’s surface based upon worldwide temperature records that have been maintained by humans since the 1880s. Global warming is the combined result of anthropogenic emissions of greenhouse gases and changes in solar irradiance. According to the World Meterological Organisation (WMO), the decade of 1998-2007 is the warmest on record. According to Intergovernmental Panel on Climate Change (IPCC), anthropogenic gases are responsible for most of the observed temperature increase since the middle of the 20th century. Increased global temperature will cause sea-levels to rise and will change the amount and pattern of precipitation, including expansion of subtropical deserts. The continuing retreat of glaciers, permafrost, and sea-ice is expected with Arctic region being particularly affected. Other likely effects include shrinkage of Amazon rainforest and Boreal forest, increase in the intensity of extreme weather events, species extinctions and changes in agricultural yields. Political and public debate continues regarding the appropriate response to global warming. The available options are mitigation to reduce further emissions, adaptation to reduce the damage caused by warming and more speculatively, geoengineering to reverse global warming. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gas emissions.