|
December 11,
2002-16
Copyright © 2002 Earth Policy Institute
GLOBAL TEMPERATURE NEAR RECORD FOR 2002
Takes Toll in Deadly Heat Waves, Withered Harvests, and Melting
Ice
Lester R. Brown
Temperature data for the first 11 months
of 2002 indicate that this year will likely be the second warmest
on record, exceeded only by 1998. These data from the Goddard Institute
for Space Studies indicate that the temperature for the first 11
months has averaged 14.65 degrees Celsius (58.37 degrees Fahrenheit),
down slightly from the record high of 14.69 in 1998, but well above
the average temperature of 14 degrees Celsius that prevailed from
1951 to 1980.
Studying these annual temperature data, one gets the unmistakable
feeling that temperature is rising and that the rise is gaining
momentum. A year ago, we noted that the 15 warmest years since recordkeeping
began in 1867 had occurred since 1980. Barring a dramatic drop in
temperature for December, we can now say that the three warmest
years on record have come in the last five years.
In addition to the longer-term annual temperature trend, recent
monthly data also indicate an accelerating rise. In contrast to
local temperatures, which fluctuate widely from season to season,
the global average temperature is remarkably stable throughout the
year because the seasonal contrasts of the northern and southern
hemispheres offset each other. The temperature for January of this
year of 14.72 degrees Celsius was the highest on record for January.
The 14.91 degrees for March made it the warmest March on record.
And in seven of the next eight months—April
through November—the
temperature was either the second or the third warmest. October
was the fourth warmest.
Since 1980, decadal average temperatures have risen well above the
14 degrees Celsius average for the span from 1951 to 1980, which
is defined as the norm. During the 1980s, the global temperature
averaged 14.26 degrees. In the 1990s it was 14.38 degrees. During
the first three years of this decade (2000-2002), it has been 14.52
degrees. (See ).
Rising temperature does not come as a surprise to atmospheric scientists
who analyze the climate effects of rising atmospheric levels of
carbon dioxide, the principal greenhouse gas. Each year since detailed
recordkeeping began in 1959, the concentration of CO2
in the atmosphere has climbed to a new high, making it one of the
most predictable of all global environmental trends.
The rise in atmospheric CO2 levels is the
result of massive fossil fuel burning that has simply overwhelmed
nature's capacity to absorb carbon dioxide. The temperature rises
observed over the last two decades are in line with the results
of research using computerized global climate models to project
the effects of rising CO2 levels on the earth's
climate.
The Intergovernmental Panel on Climate Change (IPCC), a group of
more than 1,500 of the world's leading climate scientists, reports
that if atmospheric CO2 levels continue to
rise as projected, the earth's average temperature will rise by
1.4-5.8 degrees Celsius during this century. The lower end of the
projected increases would lead to a 0.14 degree rise in temperature
per decade during this century, roughly the same as during each
of the last two decades of the last century. But the higher end
of the projected temperature range means an increase of nearly 0.6
degrees per decade, a rate that could be extraordinarily disruptive
to both the earth's ecosystem and the economy that depends upon
it.
There are many manifestations of a higher temperature other than
thermometer readings, including deadly heat waves, scorched crops,
and ice melting. In May 2002, a record heat wave in southern India
with the temperature reaching 114 degrees Fahrenheit (45.6 degrees
C) claimed more than 1,000 lives in the state of Andhra Pradesh
alone. In societies without air conditioning, there is no ready
escape from the dangerous heat. To India's north, the temperatures
in Islamabad, the capital of Pakistan, soared to 117 degrees Fahrenheit
(47 degrees C) during June.
Farmers may now be facing higher temperatures than any generation
of farmers since agriculture began 11,000 years ago. Crop yields
have fallen as temperatures have climbed in key food-producing countries,
such as the United States and India. Many weeks of record or near-record
temperatures this past summer in the northern hemisphere, combined
with low rainfall, withered crops in many countries, and reduced
the 2002 world grain harvest to 1,813 million tons of grain, which
was well below the projected consumption of 1,895 million tons.
Crop ecologists at the International Rice Research Institute in
the Philippines have recently reported that rice fertilization falls
from 100 percent at 34 degrees Celsius (93 degrees F) to essentially
zero at 40 degrees (104 degrees F). Scientists in the U.S. Department
of Agriculture are seeing a similar effect of high temperature on
other grains. The scientific rule of thumb is that a 1 degree Celsius
rise in temperature above the optimum reduces grain yields by 10
percent.
One of the most sensitive indicators of higher temperature is ice
melting. Scientists now report ice melting in all the world's major
mountain ranges, including the Rocky Mountains, the Andes, the Alps,
and the Himalayas. In Alaska, where temperatures in some regions
have risen 5-10 degrees Celsius over the norm, ice is melting far
faster than had earlier been reported.
On Africa's snow-covered Kilimanjaro, the area covered by snow and
ice has shrunk by 80 percent since 1900. Lonnie Thompson, Ohio State
University glaciologist, reports that all the snow and ice there
may disappear by 2020. For Americans, another landmark—Glacier
National Park—may
be forced to change its name. Half of its glaciers have already
disappeared, and the U.S. Geological Survey projects that the remaining
ones will disappear within the next 30 years.
Scientists report that ice cover in the Arctic Ocean shrank to 2
million square miles this summer compared with an average of 2.4
million square miles during the preceding 23 years. The thinning
of the ice is proceeding even faster. Since this ice is already
in the water, its loss will not affect sea level, but when incoming
sunlight strikes snow and ice, 80 percent of it bounces back into
space and 20 percent is converted to heat. Conversely, when the
incoming sunlight hits open water, only 20 percent is reflected
and 80 percent is converted into heat, warming the region.
Scientists are concerned with this warming because Greenland lies
largely within the Arctic Sea. This past summer ice melting occurred
over 265,000 square miles of the Greenland ice sheet—9
percent more than the previous maximum. If the Greenland ice sheet,
which is 1.5 miles thick in some areas, were to melt entirely, sea
level would rise 7 meters (23 feet). What happens to the ice in
the Arctic Sea and the climate in the region is of concern to the
entire world.
Some industries are beginning to respond. Worried about the loss
of snow in mountainous regions and frustrated by the lack of progress
in stabilizing climate, the National Ski Areas Association, the
U.S. trade association for the industry, plans to soon announce
its "Keep Winter Cool" campaign. To do its part to reduce carbon
emissions, the industry plans to purchase wind-generated electricity
to run lifts and snowmaking equipment. Other sectors of the economy,
such as agriculture and the insurance industry, may also begin to
press for a steep reduction in carbon emissions as the high costs
of failing to stabilize climate become unacceptable.
Changing the earth's climate is a serious matter, one that should
not be taken lightly. The risk is that climate change could soon
spiral out of control, leaving future generations with soaring temperatures,
withered harvests, deadly heat waves, melting ice, and rising seas.
If we do not act quickly to stabilize climate, our grandchildren
may never forgive us.
Copyright
© 2002 Earth Policy Institute
View Data
Email this Update to a friend
Printer friendly format |
|
Email this Update to a friend
Printer friendly format
View Data
FOR ADDITIONAL INFORMATION
From Earth Policy Institute
Lester R. Brown, Eco-Economy:
Building an Economy for the Earth (New York: W.W. Norton
& Company, 2001).
Lester R. Brown, Janet Larsen, and Bernie Fischlowitz-Roberts,
The Earth Policy Reader
(New York: W.W. Norton & Company, 2002).
Lester R. Brown, "Rising Temperatures & Falling
Water Tables Raising Food Prices," Eco-Economy
Update, 21 August 2002.
Lester R. Brown, "Earth's Ice Melting Faster Than
Projected," Eco-Economy Update,
12 March 2002.
From Other Sources
Seth Dunn, "Global Temperature Close to a Record"
and "Carbon Emissions Reach New High," in Worldwatch Institute,
Vital Signs 2002: The Trends that are Shaping Our Future
(New York: W.W. Norton & Company, 2002), pp. 50-53.
Goddard Institute for Space Studies, NASA Goddard
Space Flight Center Earth Sciences Directorate, “Global
Temperature Anomalies in .01 C,” updated December 2002,
http:/www.giss.nasa.gov/data.
IPCC, Climate Change 2001. Contributions of Working
Groups I, II, and II to the Third Assessment Report of the Intergovernmental
Panel on Climate Change (Cambridge and New York: Cambridge University
Press). Text and summaries available at http:/www.ipcc.ch.
C.D. Keeling, T.P. Whorf, and the Carbon Dioxide
Research Group, “Atmospheric Carbon Dioxide Record from Mauna
Loa,” Scripps Institution of Oceanography, University of California,
13 June 2002, http:/cdiac.esd.ornl.gov/
ftp/ndp001/maunaloa.co2.
LINKS
Carbon Dioxide Information Analysis Center
http:/cdiac.esd.ornl.gov
Intergovernmental Panel on Climate Change
http:/www.ipcc.ch
International Research Institute for Climate Prediction
http:/iri.ldeo.columbia.edu/
climate/cid/
National Climatic Data Center
http:/lwf.ncdc.noaa.gov/oa/
ncdc.html
National Oceanic and Atmospheric Administration
(NOAA)
http:/www.noaa.gov
Scripps Institution of Oceanography
http:/www.sio.ucsd.edu
United Nations Framework Convention on Climate Change
http:/www.unfccc.de
|
