Global warming myths debunked
MYTH: Accurate weather predictions a few days in advance are hard to come by. Why on earth should we have confidence in climate projections decades from now?
FACT: Climate prediction is fundamentally different from weather prediction, just as climate is different from weather.
It is often more difficult to make an accurate weather forecast than a climate prediction. The accuracy of weather forecasting is critically dependent upon being able to exactly and comprehensively characterise the present state of the global atmosphere. Climate prediction relies on other, longer ranging factors. For instance, we might not know if it will be below freezing on a specific December day, but we know from our understanding of the region's climate that the temperatures during the month will generally be low. Similarly, climate tells us that London tends to be rainy, and Florida is usually warm.
Today’s climate models can now reproduce the observed global average climates over the past century and beyond. Such findings have reinforced scientists' confidence in the capacity of models to produce reliable projections of future climate. Current climate assessments typically consider the results from a range of models and scenarios for future heat-trapping emissions in order to identify the most likely range for future climatic change.
MYTH: As the hole in the ozone layer shrinks, global warming will no longer be a problem.
FACT: Global warming and the hole in the ozone layer are two different problems.
The hole in the ozone layer is a thinning of the stratosphere's ozone layer, which is roughly 9 to 31 miles above the earth's surface. The depletion of the ozone is due to man-made chemicals like chlorofluorocarbons (CFCs). A thinner ozone layer allows more harmful ultraviolet (UV) radiation to reach the earth's surface.
Global warming, on the other hand, is the increase in the earth's average temperature due to the build-up of CO 2 and other greenhouse gases in the atmosphere from human activities.
© Environmental Defense; reprinted with permission. For more information, visit their website at www.environmentaldefense.org.
