U.N. Global Warning Forecast:
Up to 10.5 Degrees F, Hotter in 21st Century
"The
idea of having a planet that really warmed 10 degrees is rather
baffling. That's the same change we saw back to the last Ice Age.
And obviously that was a hugely different kind of world to live
on. So, if we really experience something at the high end of temperature
increase, it sounds like there is a possibility for widespread
disaster."
-
Drew Shindell, Ph.D., Atmospheric Physicist
The
largest decline in a mammal population ever recorded by modern
scientists has occurred in the otter population of the Aleutian
Islands off the west coast of Alaska. In the 1980s, as many as
100,000 otters inhabited the islands. Today, there are only about
6,000 left. And 70% of that decline occurred between 1992 and
2000, a rate of decline that scientists say is unprecedented for
any mammal population in the world. Researchers have been trying
to find out what happened. And the answer seems to be global warming.
Warmer ocean currents in the Aleutians have driven out the huge
population of seals and sea lions that used to be the staple food
of killer whales. When the seals and sea lions disappeared, the
whales turned to otters for food. As water temperatures increased,
so did the salmon population. Salmon have attracted sharks. So,
in a few short years a warmer water temperature has transformed
the once safe mammal sanctuary of the Aleutian Islands into a
feeding ground for predators.
Just
how bad could global warming be over the next several decades?
This past week, the United Nations Intergovernmental Panel on
Climate Change released a 1000 page volume entitled "Climate Chnage
2001: The Scientific Basis" about what could happen based on computer
projections from atmospheric physics laboratories around the world.
The study has taken five years of new data and input from global
scientists to help understand what the consequences of greenhouse
gas build up will be. The bottom line is that every computer model
projects the same outcome: this planet will steadily warm up over
the next hundred years from 3 to 10.5 degrees Fahrenheit.
To
put those numbers in perspective: Scientists thought it was alarming
to learn that in the 20th century the global annual mean temperature
had risen 1 degree Fahrenheit. That means all the world's sophisticated
climate modeling computers agree that the next hundred years could
warm three to ten times as much. Greater extremes of drought and
flooding along with accelerated sea level rise are some of the
consequences.
I
discussed the climate change report with Dr. Drew Shindell, Associate
Research Scientist for Global Climate Change at the NASA Goddard
Institute for Space Studies known as GISS. He is also Adjunct
Research Scientist at the Center for Climate Systems Research
at Columbia University's Dept. of Earth and Environmental Sciences
in New York City.
Interview
Drew Shindell, Ph.D., Atmospheric Physicist and Associate Research
Scientist for Global Climate Change at the NASA Goddard Institute
for Space Studies (GISS) and Adjunct Research Scientist at the
Center for Climate Systems Research at Columbia University's Dept.
of Earth and Environmental Sciences, New York City:
"It's
a frightening thought if we were to really hit the high end in the
projections. And there is a lot of uncertainty, so we end up with
a range from a maximum of 10.5 degrees or so down to only a few
degrees. But even the lower end is still quite a large amount of
warming and a few degrees warmer is more than we saw during the
20th C. The possibility for changes in something like rainfall especially
is rather alarming. Rainfall is a very difficult thing to predict,
or precipitation in general. But most of the models indicate that
the largest decreases in rainfall would be in the tropical areas
which are already rather limited in the amount of rain they get.
What
we are talking about is that the areas up in the north and mid latitudes
where the countries are fairly well developed and can cope more
readily with climate change would not suffer nearly as much as the
developing world which would see large changes in precipitation,
more droughts, more floods, a lot more weather extremes. And of
course, those areas are not well equipped to cope with that. So
we see a lot of possibility for the developing world to suffer much
more severe weather and damage to crop yields especially which is
a frightening thing.
WHERE
FOOD IS ALREADY A PROBLEM, FOOD WOULD BECOME A GREATER PROBLEM.
Exactly.
And the infrastructure in those countries are the least equipped
to cope with that kind of change. Just having a warmer planet means
that the water in the oceans will expand just because the air is
warmer and the water itself becomes warmer. There is also the possibility
of the melting of ice sheets in the polar regions which is quite
uncertain. If such a thing were to take place and all of that water
that's now locked up in the fresh water in the big ice sheets were
to slide into the ocean, we would have a much larger rise in sea
level. But even without that, it seems extremely likely that sea
level will continue to rise as it has been doing during the 20th
century just due to the thermal expansion of heating the water.
So that is one quite probable outcome or impact of the warming temperatures.
AND
WE'RE TALKING ABOUT AT LEAST A 3 FOOT SEA LEVEL RISE AND IF THERE
WAS A 10.5 INCREASE GLOBALLY IN THE NEXT 100 YEARS, THAT 3 FEET
MIGHT GO 5 TIMES HIGHER?
It
could be something like that. It could be a very large increase.
That would require something like a very large melting of the ice
sheet in Greenland or a very large portion of the ice sheet over
Antarctica sliding into the ocean. These are things we don't have
a lot of confidence in our ability to predict.
IS
IT FAIR TO SAY THAT THE GENERAL CONSENSUS OF SCIENTISTS WHO ARE
STUDYING CLIMATE CHANGE TODAY IS THAT WE ARE IN A GLOBAL WARMING
TREND IN WHICH WE DO NOT HAVE ANY DATA TO SUGGEST THAT THAT GLOBAL
WARMING WILL END OVER THE NEXT 100 YEARS?
I
think that is quite accurate. I think the data that we have is quite
clear in showing that the surface temperatures and temperatures
in much of the lower atmosphere have increased. I think the majority
of evidence in all scientists' minds points to human activities
as having been responsible for a large portion of this increase.
And we don't see any likely drastic change in these activities and
furthermore, there is a large time lag of several decades in how
long it takes for the entire planet to respond to the changes. So,
we're still going to be feeling the effects of what we did in the
20th C. when we know there were very large emissions of greenhouse
gasses well into the 21st C. regardless of what we do in the 21st.
So, I think most people, most scientists would agree, that almost
all scientists would agree that the earth is almost without question
going to warm during the 21st C.
WHAT
DO YOU SAY TO PEOPLE WHO LOOK AT THIS WINTER OF 2001 AND SAY THIS
IS AS COLD AS IT'S BEEN IN 10 YEARS OR WHATEVER AND THEREFORE, THERE
IS NO GLOBAL WARMING?
One
year or even several years don't prove the point. It's a long-term
trend in climate that we're worried about rather than short-term
fluctuations of the weather. And just as the warm years of 1998
and 1997 and 1999 which were all record warm years. Those didn't
prove by themselves global warming. So, the year 2000 being a cold
winter, doesn't prove there is no such thing as global warming.
It's a long-term change that we're interested in here.
WHEN
YOU ARE CONSIDERING 3 TO 10 DEGREES WITH AS MUCH AS YOU KNOW ABOUT
CLIMATE AND ATMOSPHERIC PHYSICS, AND YOU ARE SITTING THERE AS A
PRIVATE INDIVIDUAL ON THE EARTH AND YOU ARE CONTEMPLATING A 10 DEGREE
CHANGE AS A POSSIBILITY OVER THE NEXT 100 YEARS, WHAT IS YOUR PERSONAL
REACTION TO THAT?
Well,
my personal reaction is that I hope we don't end up at the high
extreme. The idea of having a planet that really warmed 10 degrees
is rather baffling. That's the same change we saw back to the last
Ice Age. And obviously that was a hugely different kind of world
to live on. So, if we really experience something at that high end
(of global temperature increase), it sounds like there is a possibility
for widespread disaster.
DO
YOU GET TOGETHER WITH POLITICAL LEADERS WHO ASK SOME OF YOU TO COME
AND DISCUSS WHAT THE REALISTIC CONSEQUENCES OF 3 FEET OR ABOVE SEA
LEVEL RISE WOULD DO TO THE COAST LINE AND WOULD OFFICES LIKE FEMA
HAVE TO CONTEMPLATE THERE MAY HAVE TO BE EVACUATIONS FROM COAST
LINES?
Well,
I think agencies from around the U. S. are beginning to become more
aware that they should consider adaptation strategies to the things
that we consider more likely outcomes. And one example of that is
the American National Assessment of the Impact of Climate Change
that came out last year and was designed to have scientists to work
in partnership with local agencies and governmental bodies to try
to decide about the possible impacts and what kinds of things we
need to worry about. One example here in New York is that we worked
with the Port Authority that runs a lot of transportation facilities
and tried to look at what might happen to the ability of trains,
tunnels and so on as sea level rose around the harbor. So, I think
people are starting to look at the possible consequences and try
to figure out ways they can adapt by anticipating what's likely
to go wrong.
COULD
NEW YORK END UP HAVING TO HAVE DIKES BUILT UP AROUND IT LIKE HOLLAND?
Well,
certainly some areas quite low to the water would be likely to either
go under or have to be protected.
ARE
THEY TALKING ABOUT DIKES?
I
don't think that is something that's going to happen in the immediate
future, but I think protecting at least crucial areas of infrastructure
is something they are starting to plan for.
WHICH
MEANS THERE IS ENOUGH OF A WATER RISE TO BE POLITICALLY CONCERNING.
Yes,
I think so. It's quite clear that sea level has risen during the
20th C. And this rise in sea level is something that we have a great
deal of confidence in our ability to predict, assuming we know the
temperature change. So, if you assume a 3 to 10 degree warming,
it's quite easy to say what that will do to water. And if you stick
water on your oven, you can warm it up by a few degrees and measure
quite easily it expanded. So, it's quite a straightforward process.
RIGHT,
AS WATER INCREASES IN TEMPERATURE, IT EXPANDS AND THEREFORE, IT
GETS HIGHER.
That's
right and that's something we fully understand, so we can predict
with pretty high confidence what will go on.
IN
THE PAST COUPLE OF WEEKS PRIOR TO THE RELEASE OF THE U. N. INTERGOVERNMENTAL
PANEL ON CLIMATE CHANGE PRESS RELEASE, SOME PEOPLE SAID THAT GLOBAL
WARMING IS PHONY, GLOBAL WARMING IS NOT REAL. WHERE DO YOU PERSONALLY
THINK THOSE KINDS OF STORIES AND HEADLINES COME FROM?
There
are a few scientists out there which legitimately question some
of the uncertainties and are not convinced that global warming is
due to human impacts. Part of the scientific process is that not
everybody agrees with any particular proposed theory or explanation
for any given thing. But eventually, we tend to come to a consensus
and the vast majority of scientists working in this area are now
quite convinced that in fact the global warming we have been seeing
is most likely due to human activities.
There
is also a group of people who do not publish in credible scientific
literature who make personal attacks on authors, attack the scientific
process in general as being biased, and generally it seems to me
these people have a political agenda which is overriding their desire
to really evaluate what the scientific evidence is saying."
Additional
Information
The
United Nations Intergovernmental Panel on Climate Change (IPCC)
has produced a 3-volume report. The first volume concerns the science
of climate change with an evaluation of data from past climate information
and projections of future climate. It has been summarized in 18
pages at the website http://www.ipcc.ch based in Switzerland. The
other two volumes detail assumptions about human impacts such as
industrial and agricultural emissions that go into making projections
about what could happen in 21st Century climate change.
U.
N. Also Reports Global Warming May Be Especially Hard On Africa
Klaus
Toepfer, Executive Director of the U. N. Environment Program (UNEP)
told reporters, "It is a very dramatic situation. The evidence is
absolutely clear that the speed of global warming is going faster
and faster. Africa's share of the global population is 14%, but
it is responsible for only 3.2% of global carbon dioxide emission.
Yet, (Africans) face the most direct consequences with regard to
extreme weather conditions with regard to drought and storms."
An
example of those weather extremes occurred in 2000. Floods battered
Mazambique while prolonged drought in the Horn of Africa brought
starvation to millions of people.
Websites:
http://www.ipcc.ch http://www.giss.nasa.gov
http://www.noaa.gov
Linda
Moulton-Howe
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© 2001 Linda Moulton Howe All Rights Reserved. Republication and
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