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Did you know:

  • If just 25% of U.S. families used 10 fewer plastic bags a month, we would save over 2.5 billion bags a year.
  • Every year we throw away 24 million tons of leaves and grass. Leaves alone account for 75% of our solid waste in the fall.
  • Over 100 pesticide ingredients are suspected to cause birth defects, cancer, and gene mutations.
  • Every ton of recycled office paper saves 380 gallons of oil.
  • About 1% of U.S. landfill space is full of disposable diapers, which take 500 years to decompose.
  • Glass produced from recycled glass instead of raw materials reduces related air pollution by 20%, and water pollution by 50%.
  • Homeowners use up to 10 times more toxic chemicals per acre than farmers.
  • By turning down your central heating thermostat one degree, fuel consumption is cut by as much as 10%.
  • One ton of carbon dioxide that is released in the air can be prevented by replacing every 75 watt light bulbs with energy efficient bulbs.
  • The uncontrolled fishing that is allowed has reduced the amount of commercial species. Some species, up to one-tenth of their original population.
  • Already over half of the world's tropical forests have been lost.
  • The garbage in a landfill stays for a for about 30 years.
  • Every ton of paper that is recycled saves 17 trees.
  • Earth is 2/3 water. but all the fresh water streams only represent one hundredth of one percent.
  • 84% of all household waste can be recycled.
  • Computers pose an environmental threat because much of the material that makes them up is hazardous. A typical monitor contains 4-5 pounds of lead.
  • One gallon of motor oil can contaminate up to 2 million gallons of water.
  • Agriculture absorbs 74% of all water taken by humans from rivers, lakes, aquifers and wetlands against 18% for industry and 8% for municipalities.

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Global Warming

Global Warming

Throughout its long history, Earth has warmed and cooled time and again. Climate has changed when the planet received more or less sunlight due to subtle shifts in its orbit, as the atmosphere or surface changed, or when the Sun’s energy varied. But in the past century, another force has started to influence Earth’s climate: humanity

How does this warming compare to previous changes in Earth’s climate? How can we be certain that human-released greenhouse gases are causing the warming? How much more will the Earth warm? How will Earth respond? Answering these questions is perhaps the most significant scientific challenge of our time.

What is Global Warming?
Global warming is the unusually rapid increase in Earth’s average surface temperature over the past century primarily due to the greenhouse gases released as people burn fossil fuels. The global average surface temperature rose 0.6 to 0.9 degrees Celsius (1.1 to 1.6° F) between 1906 and 2005, and the rate of temperature increase has nearly doubled in the last 50 years. Temperatures are certain to go up further.

Earth’s natural greenhouse effect
Earth’s temperature begins with the Sun. Roughly 30 percent of incoming sunlight is reflected back into space by bright surfaces like clouds and ice. Of the remaining 70 percent, most is absorbed by the land and ocean, and the rest is absorbed by the atmosphere. The absorbed solar energy heats our planet.

As the rocks, the air, and the seas warm, they radiate “heat” energy (thermal infrared radiation). From the surface, this energy travels into the atmosphere where much of it is absorbed by water vapor and long-lived greenhouse gases such as carbon dioxide and methane.
When they absorb the energy radiating from Earth’s surface, microscopic water or greenhouse gas molecules turn into tiny heaters— like the bricks in a fireplace, they radiate heat even after the fire goes out. They radiate in all directions. The energy that radiates back toward Earth heats both the lower atmosphere and the surface, enhancing the heating they get from direct sunlight.
This absorption and radiation of heat by the atmosphere—the natural greenhouse effect—is beneficial for life on Earth. If there were no greenhouse effect, the Earth’s average surface temperature would be a very chilly -18°C (0°F) instead of the comfortable 15°C (59°F) that it is today.

The enhanced greenhouse effect
What has scientists concerned now is that over the past 250 years, humans have been artificially raising the concentration of greenhouse gases in the atmosphere at an ever-increasing rate, mostly by burning fossil fuels, but also from cutting down carbon-absorbing forests. Since the Industrial Revolution began in about 1750, carbon dioxide levels have increased nearly 38 percent as of 2009 and methane levels have increased 148 percent.
The atmosphere today contains more greenhouse gas molecules, so more of the infrared energy emitted by the surface ends up being absorbed by the atmosphere. Since some of the extra energy from a warmer atmosphere radiates back down to the surface, Earth’s surface temperature rises. By increasing the concentration of greenhouse gases, we are making Earth’s atmosphere a more efficient greenhouse.