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Global Warming
Overview

Contents:
Introduction | Solutions | Reckless Energy Policy Drives Global Warming | The Hard Facts of Global Warming | States and Industry | PDF Version of this Report


The Hard Facts of Global Warming

The science behind global warming is conclusive and well-documented. For over fifty years, scientists have been measuring the concentrations of carbon dioxide in the atmosphere from the Mauna Loa laboratory in Hawaii. They have found that the concentration of CO2 has been increasing by about one part per million every year - an increase that is caused by the burning of unprecedented amounts of fossil fuels over the last two hundred years of industrialization. Scientists have also been studying ice to tell us about our planet's climate history. Data taken from deep core drilling on the ice sheets near the north and south poles show that historically, higher concentrations of carbon dioxide in the atmosphere have lead to global warming. We are already seeing this trend of warming today - the ten hottest years on record have all occurred within the last fifteen years.

Mauna Lao CO2 concentrations
Click to see larger version of this graphic

So how much difference can a few degrees make? Plenty. Throughout history, major shifts in temperature occurred at a very slow rate - usually changing only a few degrees over thousands of years. However, our emission of greenhouse gas pollution is causing global warming to occur at a much faster rate than ever before. The world's leading climate scientists project that during our children's lifetimes, global warming will raise the average temperature of the planet by 3 to 10 degrees Fahrenheit - a shift that will rival the change in temperature since the last ice age. Unless we slow, and ultimately reverse, the buildup of greenhouse gases in the atmosphere, we will have decades - not millennia - to deal with radical changes in weather patterns, sea levels and threats to human health. These radical changes are already occurring, and are having disastrous affects. The French Government blames global warming for a heat wave that killed 10,000 people in 2003. Physicians at the Harvard University and Johns Hopkins medical schools have issued grim assessments that global warming may be causing the spread of infectious diseases like West Nile Virus and malaria. Additionally, extreme weather events have become more common - the World Meteorological Organization has concluded that the increase in hurricanes, tornadoes, and flooding can be blamed on global warming, and that the frequency and severity of these events will increase as the planet continues to warm. These changes are the result of only a one degree rise in temperature over the last century. If temperatures continue to rise as high as scientists are projecting, the changes we are experiencing now will pale by comparison. If we don't begin to act now to curb global warming, our children will live in a world where the climate will be far less hospitable than it is today. The majority of the world's leading climate scientists and researchers have come to the same conclusion - that the dangers of global warming are serious, and that to avoid them, we must curb our emissions of greenhouse gases.

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