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Global Warming Fast Facts
National Geographic News
Global warming, or climate change, is a
subject that shows no sign of cooling down!
Here's the lowdown on why it's happening, what's
causing it, and how it might change the planet.
Is It Happening?
Yes. Earth is already showing many signs
of worldwide climate change.
• Average
temperatures have climbed
1.4 degrees
Fahrenheit
(0.8 degree Celsius) around the world
since 1880, much of this in recent decades,
according to NASA's Goddard Institute for Space
Studies.
• The rate of warming is increasing.
The 20th century's last two decades were the
hottest in 400 years
and possibly the warmest for several millennia,
according to a number of climate studies. And the
United Nations' Intergovernmental Panel on Climate
Change (IPCC) reports that
11 of the past
12 years are among the dozen warmest since
1850.
• The Arctic is feeling the effects the
most... and we will very soon! Average
temperatures in Alaska, western Canada, and eastern
Russia have risen at twice the global average,
according to the multinational Arctic Climate Impact
Assessment report compiled between 2000
and 2004.
• Arctic ice is rapidly disappearing,
and the region may have its first completely
ice-free summer by 2040
or earlier. Right now and more and more today
Polar bears and indigenous cultures
are already suffering from
the sea-ice loss.
• Glaciers and mountain snows are
rapidly melting-for example,
Montana's Glacier National Park
now has only 27
glaciers, versus 150
in 1910. In the Northern
Hemisphere, thaws also come a week
earlier in spring and
freezes begin a week later.
• Coral reefs, which are highly
sensitive to small changes in water temperature,
suffered the
worst bleaching-or die-off in response to
stress-ever recorded in 1998,
with some areas seeing bleach
rates of 70
percent. Experts expect these sorts of
events to increase in frequency and intensity in the
next 50 years as sea temperatures rise.
• An upsurge in the amount of extreme
weather events, such as
wildfires,
heat waves,
and
strong tropical storms, are also
attributed to climate change by experts. |
