Quick Facts About Global Warming

Global warming is one of the most critical problems facing the environment today, according to climate change experts such as Cornell Professor Charles H. Greene. Predictions forecast that it will raise sea levels, change global weather patterns and drive many species to extinction. The effects of global warming will have a human toll, so building an economy that is less reliant on greenhouse gases will be an important challenge in the near future.

Causes

When greenhouse gases such as carbon dioxide, methane, nitrous oxide and water vapor enter the atmosphere, they trap the heat from the sun near the Earth. This causes an increase in the global temperature, which contributes to the phenomenon known as global warming. The effect is similar to the one produced in a greenhouse. Nations have already begun committing to the reduction of these gases. The Washington Post reports that the United States has pledged to reduce 17 percent of emissions by 2020.

Temperature Increase

According to NASA's Goddard Institute for Space Studies (via National Geographic), average worldwide temperatures have already climbed by 1.4 degrees Fahrenheit (0.8 degrees Celsius) since 1880. The 1980s and 1990s were warmer than any decade in the 400 prior and possibly for the past several millennia. The United Nations' Intergovernmental Panel on Climate Change released a 2007 report that claimed the period between 1995 and 2006 saw 11 of the 12 warmest years since 1850.

Sensitive Environments

Sensitive environments have felt some of the worst effects of global warming. Arctic ice and glaciers are disappearing at such a rate that the region may face an ice-free summer by 2040 according to computer model data from a paper in the journal Geophysical Research Letters. Montana's Glacier National Park alone is down to 27 glaciers from 150 in 1910. In addition, the Proceedings of the National Academy of Sciences published a paper that found some areas of coral reefs are experiencing rates of bleaching--death in response to stress--as high as 70 percent.

Intense Weather

Despite its name, global warming is not just about temperature. It also amplifies intense weather and is a potential contributing factor in such phenomena as wildfires, famines, heat waves and strong tropical storms. If global warming continues to get worse, then ambivalent weather patterns will reach further extremes. For this reason, global warming also goes by the name of climate change.

Effects

Concerns exist that global warming may raise the worldwide sea level by 7 to 23 inches, flooding many islands and coastal areas across the globe. In addition, a million species face extinction from changing ecosystems and acidifying oceans, and the ocean's circulation could be irrevocably altered. Global warming could create a positive feedback effect, releasing into the air more methane or carbon trapped beneath permafrost and undersea deposits.