The Effects of Green house in the world.

The Effects of Green house in the world.

Greenhouse Effect, the capacity of certain gases in the atmosphere to trap heat emitted from Earth’s surface, thereby insulating and warming the planet. Without the thermal blanketing of the natural greenhouse effect, Earth’s climate would be about 33°C (about 59°F) cooler—too cold for most living organisms to survive.

The American Geophysical Union, a leading scientific organization, issued a warning in January 1999 that global warming trends are cause for concern and may be at least partially attributable to human activity. An Encarta Yearbook article reported on the organization’s statement.

The greenhouse effect has warmed Earth for over 4 billion years. Now scientists are growing increasingly concerned that human activities may be modifying this natural process, with potentially dangerous consequences. Since the advent of the Industrial Revolution in the 1700s, humans have devised many inventions that burn fossil fuels such as coal, oil, and natural gas. Burning these fossil fuels, as well as other activities such as clearing land for agriculture or urban settlements, releases some of the same gases that trap heat in the atmosphere, including carbon dioxide, methane, and nitrous oxide. These atmospheric gases have risen to levels higher than at any time in at least the last 650,000 years. As these gases build up in the atmosphere, they trap more heat near Earth’s surface, causing Earth’s climate to become warmer than it would naturally.

The December 1997 summit on global warming in Kyoto, Japan, which included representatives from the United States, the European Union (EU), and many developing nations, reached an agreement for reducing emissions of gases that many scientists believe may lead to global warming. One such scientist, Professor Stephen Schneider of Stanford University in California, attended the summit and wrote the following analysis of its results.

Scientists call this unnatural heating effect global warming and blame it for an increase in Earth’s surface temperature of about 0.6°C (about 1°F) over the last century. Scientists project global temperatures to continue rising during the 21st century. Warmer temperatures could melt parts of polar ice caps and most mountain glaciers, causing a rise in sea level that would flood coastal regions. Global warming could also affect weather patterns causing, among other problems, prolonged drought or increased flooding in some of the world’s leading agricultural regions.