Right now we and our fellow inhabitants of the Earth are facing the most
crucial environmental problem of our time; humanity's large-scale,
inadvertent experiment with the world's climate system. How we deal with
this problem will affect our lives and the lives of our children for decades
to come. It's a problem that is not readily apparent, having come upon us
slowly. But in it's a worldwide scale it could represent the single greatest
threat ever faced by humanity.
Earth's climate has been warming at an accelerated rate for the last century
and a half. Our average annual global temperature is about 1 degree Fahrenheit
(0.6 degree Centigrade) higher than it was at the beginning of the 20th Century.
This may not seem like a lot, but we are already seeing the effects of warmer
temperatures. The 1990s were the warmest decade on record; 1998 was the warmest
year - at least since 1861. Glaciers around the world are in rapid retreat. The
snow cap on Africa's Mt. Kilimanjaro will probably disappear before the end of the
decade. According to the Navy, the thickness of the Arctic ice cap has been reduced
by 40% over the last forty years. The melting of polar ice along with thermal
expansion has caused average sea levels to rise around the globe by 4 to 10 inches
since 1900.
Why the Earth is warming is not an easy issue to understand. Many factors play into
the heating and cooling of the planet. Is global warming caused by human activities,
in whole, in part, or not at all? Are there other, natural causes at work over which
we can have no influence at all? Understanding past climate trends and being able to
project future climate change accurately is a daunting task. And then, even if we know
what direction the world's climate is heading, can we predict the range of possible
impacts?
If global warming is being caused by human activities, and if it is likely to increase,
then we have a moral obligation - to our fellow residents on the planet, and to our
children - to change our ways. Given the current Administration's decision to reject
the 1998 Kyoto Protocol on global warming and challenge the scientific basis for
international action - a move that brings us to the brink of being branded a "rogue"
environmental state - makes an understanding of this topic more urgent than ever.
Over the next three weeks I'll be exploring global warming — how it works, why it's
happening, and its consequences for humanity — and how we as individuals can begin
to deal with it.