Gore got some unusually good press recently for his movie
An Inconvenient Truth. The movie is about the greenhouse effect
and global warming, issues that had long been a cause with
Mr Gore, and made him the butt of much humour, as the preoccupation
of oddballs like himself.
A turnaround in public conviction is underway, and its
even more striking in the scientific community. There was
a time when the science surrounding global warming was said
to be too uncertain to form any basis for policy decisions,
either in science itself, business, or government, but that
is all changing. The research is now in, and it shows a strong
consensus that an artificially warming world is a real phenomenon
that poses real danger.
But first, a few words about the meaning of the greenhouse
effect and global warming for non-scientific
readers like myself.
The greenhouse effect is the rise in temperature that the
Earth experiences because certain gases in the atmosphere
(eg, carbon dioxide, nitrous oxide, and methane) trap energy
from the sun.
Greenhouses, as we know, are small glass houses used to grow
plants, especially in winter. They work by trapping heat from
the sun. The glass panels let in light but keep heat from
escaping. This causes the greenhouse to heat up, much like
a car parked in sunlight, and it keeps the plants warm enough
to live through the winter.
Greenhouse gases in the atmosphere behave much like glass
panes in a greenhouse. Sunlight enters the Earths atmosphere,
passing through a blanket of such gases. As it reaches the
Earths surface, air, land, and water absorb the sunlights
energy. Once absorbed, the energy is sent back into the atmosphere.
Some of it passes back into space, but much of it is trapped
by the concentration of gases, and global warming is the result.
The consensus now is that climatic change today is largely
due to emissions of greenhouse gases from human activities
(not natural causes), including industrial processes, fossil
fuel combustion, and changes in land use, such as deforestation.
Temperatures at the Earths surface have increased by
an estimated 1.4 degrees F between 1900 and 2005. The last
decade was the hottest of the past 150 years and perhaps the
last millennium. The hottest 22 years on record have occurred
since 1980, with 2005 being the hottest year of all. Projections
of future warming suggest an increase of 2.5 degrees F to
10.4 F by 2100.
The global scientific community today agrees that these facts
represent accurate scientific conclusions.
In 2003, the American Geophysical Union and American Meteorological
Society both declared that signs of global warming had become
In 2004, the American Association for the Advancement of Science
said there was no longer any substantive disagreement in the
scientific community on the issue.
In 2005, the (American) National Academy of Sciences joined
the science academies of Britain, China, Germany, Japan and
other nations in a joint statement that there was now strong
evidence of significant global warming.
Global warming means that the Earths surface, temperature,
and seas are getting warmer. Greenland glaciers are vanishing,
spring is coming sooner, and rainfall patterns are changing.
But other possibilities pose more serious risks to the global
economy and the global environment.
Suppose, for instance, that precipitation shifted away from
breadbasket regions, sending rain clouds instead to the worlds
deserts. Poorer countries will be far less capable of coping
with the effects of such changes. In an interdependent world,
it would mean global disaster.
Some people do not regard the warming trend as wholly bad.
In their view, a warmer world would reduce or moderate the
global demand for energy, also open up vast areas of Alaska,
Canada, and Russia for development. This is a possible scenario,
but in a warmer world such benefits will be offset by equally
The National Academy of Sciences predicts in the coming century,
sea levels may rise by as much as three feet, tropical storms
may continue to increase in number and fury, and diseases
now confined to equatorial regions may spread farther North
The scientific consensus is a wake-up call for all societies.
In 1997 the UN adopted what many now view as a shaky Kyoto
Protocol (amending the 1992 Framework Convention on Climate
Change). The protocol targeted six greenhouse gases, including
the big three: carbon dioxide, nitrous oxide, and methane,
that signatory nations committed themselves to curbing. The
problem with Kyoto is false reporting, especially by the bigger,
more industrialised nations.
Global warming should be everyones responsibility. A
host of ordinary activities in their own way contribute to
itand can alleviate it. All uses of electricity release
greenhouse gases into the air. Habits of conservation curb
them. So does recycling, and efforts at reforestation. Trees
absorb carbon dioxide, the most significant greenhouse gas
contributor to global warming.
The main form of reduction, of course, would be to lessen
emissions from fossil fuel (coal and oil) combustion. This
is the challenge, and its not impossible. Society has
brought other environmental threats in the past under control.
Take smog, for example. We do not hear as much about this
as we used to. Similarly for acid rain. There was a time when
a new, devastating Silent Spring was thought to
be imminent from unchecked acid rain. We no longer hear much
about this either. Even Aids itself has shown whats
possible when a grave issue is recognised for what it is,
ie not just a slight blip on the radar of societys concerns,
but a matter of global menace.
Global warming is such a threat today. Its not simply
a cause for environmentalists, but something much more fundamental,
threatening economies and lives everywhere. Taking it seriously
is an imperative, not just another option.