The Global warming

Eassay Outline

1. Introduction
2. Evidence of global warming
3. Causes
4. Effects
5. Measures to reduce warming
6. Global concern

Global warming is the continuing rise in the average temperature of Earth’s atmosphere and oceans. Global warming became more widely popular after 1988 when NASA climate scientist James Hansen used the Term in a testimony to Congress. His testimony was widely reported and afterward global warming was commonly used by the press and in public discourse.

The evidence for the temperature rise is unequivocal and scientists have determined that most of it is caused by human activities. This find in 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. During the 21st century the global surface temperature is likely to rise further.

Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere. Over the last three decades of the 20th century, gross domestic product per capita and population growth were the main drivers of increases in greenhouse gas emissions.

An increase in global temperature will cause sea levels to rise and a probable expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing retreat of glaciers and sea ice. Other likely effects of the warming include more frequent occurrence of extreme weather events including heat waves, droughts and heavy rainfall events, species extinctions due to shifting temperature regimes, and changes in agricultural yields. Many countries, both developing and developed, are aiming to use cleaner and less polluting technologies. Use of these technologies aids mitigation and could result in substantial reductions in CO2 emissions. Policies include targets for emissions reductions, increased use of renewable energy, and increased energy efficiency. Studies indicate substantial potential for future reductions in emissions.

National science academies have called on world leaders for policies to cut global emissions. Environmental organizations and public figures have emphasized changes in the current climate and the risks they entail, while promoting adaptation to changes in infrastructural needs and emissions reductions. Some fossil fuel companies have scaled back their efforts in recent years, or called for policies to reduce global warming.