Global warming is caused by the release of carbon dioxide
and other heat-trapping gases into earth's atmosphere.
The gases act like a thick blanket, trapping the sun's
heat and causing the planet to warm up. Increase the
gases and the warming increases, too. These gases are
created when we burn fossil fuels in our cars and power
plants as well as by loss of forests and agriculture.
Scientists find clues to global warming by studying
remnants of the past in ancient glacial ice, ocean sediments
as well as tree and coral rings. Global warming is problematic
to human civilization because it will cause increasingly
severe storms and droughts, glaciers to melt, rising
seas, changes in weather patterns, and the spread of
Automobiles and coal-burning power plants are the two
biggest sources of carbon dioxide in the U.S. Clearing
of forests is also an important source worldwide. Scientists
say that unless we curb global warming emissions, average
temperatures could rise by 3 to 9 degrees by the end
of the century.
SURPRISING SCIENTIFIC STATISTICS ON GLOBAL WARMING
Recent data from Antarctic ice cores indicate that carbon
dioxide concentrations are now higher than at any time
during the past 650,000 years, which is as far back
as measurements can now reach.
2005 was the warmest year on
record since atmospheric temperatures have
been measured. The ten warmest years on record have
all been since 1990. In summer 2005, heat records were
broken in hundreds of U.S. cities. Over the past 50
years, the average global temperature has increased
at the fastest rate in recorded history.
In 2003, heat waves caused over 30,000 deaths in Europe
and 1500 deaths in India.
Since 1978, arctic sea ice has been shrinking by about
9 percent per decade. Seagulls were spotted for the
first time at the North Pole in 2000. The snows of Mt.
Kilimanjaro, at their current rate of melt, may be gone
PREDICTED EFFECTS AS TEMPERATURES RISE
Global warming is predicted to
increase the intensity of hurricanes. In the past
several decades, the number of Category 4 and 5 hurricanes
globally has almost doubled. Because the ocean is
getting warmer, tropical storms can pick up more energy
and become far more powerful.
Even as severe storms cause flooding
in some areas, droughts and wildfires will increase
Low-lying islands will no longer
be habitable due to rising sea level.
Forests, farms and cities will
face troublesome new pests and more mosquito-borne
Disruption of habitats such as
coral reefs and alpine meadows could drive many plant
and animal species to extinction.