Global warming is the continuing rise in the average temperature of Earth's atmosphere and oceans. Global warming is caused by increased concentrations of greenhouse gases in the atmosphere, resulting from human activities such as deforestation and burning of fossil fuels. This finding is recognized by the national science academies of all the major industrialized countries and is not disputed by any scientific body of national or international standing.The instrumental temperature record shows that the average global surface temperature increased by 0.74 °C (1.33 °F) during the 20th century. Climate model projections are summarized in the Fourth Assessment Report (AR4) by the ...view middle of the document...
Hence, the ecosystem services upon which human livelihoods depend would not be preserved
The causes of Global warming are as following:
The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet's lower atmosphere and surface. It was proposed by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896.
Naturally occurring amounts of greenhouse gases have a mean warming effect of about 33 °C (59 °F).[C] The major greenhouse gases are water vapor, which causes about 36–70 percent of the greenhouse effect; carbon dioxide (CO2), which causes 9–26 percent; methane (CH4), which causes 4–9 percent; and ozone (O3), which causes 3–7 percent. Clouds also affect the radiation balance through cloud forcings similar to greenhouse gases.
Since the late 20th century, changes have been observed in the trends of some extreme weather and climate events, e.g., heat waves. Human activities have, with varying degrees of confidence, contributed to some of these observed trends. Projections for the 21st century suggest continuing changes in trends for some extreme events. Solomon et al. (2007), for example, projected the following likely (greater than 66% probability, based on expert judgement) changes:
· An increase in the areas affected by drought;
· Increased tropical cyclone activity;
· And increased incidence of extreme high sea level
Projected changes in extreme events will have predominantly adverse...