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August 21, 2002-12
Copyright © 2002 Earth Policy Institute
RISING TEMPERATURES & FALLING WATER TABLES RAISING FOOD PRICES
Record World Grain Harvest Shortfall of 83 Million Tons in Prospect
Lester R. Brown
On Monday, August 12th, the U.S. Department
of Agriculture (USDA) released an updated estimate of the world
grain harvest for 2002, reducing it to 1,821 million tons from July's
estimate of 1,878 million tons. With world grain consumption this
year projected at 1,904 million tons, this lower harvest leaves
a shortfall of 83 million tons.
The precipitous drop in the month-to-month estimated harvest triggered
an accelerated rise in prices of wheat and corn in world markets.
In recent months, wheat futures for December delivery have climbed
from $2.83 a bushel to $3.70--a gain of 31 percent. Corn prices
have climbed by a similar amount. And this is only the beginning.
As grain prices climb, so too will prices of the products derived
from grain, such as bread, breakfast cereals, pasta, and livestock
products, including meat, milk, and eggs.
This is the third consecutive year in which world grain production
has fallen short of consumption. In 2000, the shortfall was 35 million
tons; in 2001, it was 31 million tons. Combined, these three annual
deficits--totaling 149 million tons--have dropped grain stocks to
the lowest level in three decades.
At the end of this crop year, world wheat carryover stocks--the
amount in the bin as the new harvest begins--are estimated at 23
percent of annual consumption, the lowest in 28 years. For rice,
carryover stocks amounted to 28 percent of annual consumption, the
lowest in 18 years. For corn, the third of the leading cereals,
carryover stocks are less than 15 percent of annual consumption,
the lowest in the 40 years since recordkeeping began.
Three key factors have contributed to the reduced harvest in 2002:
low grain prices at planting time, crop-withering temperatures,
and falling water tables. Several years of low grain prices have
discouraged farmers from investing in land improvement and other
production-enhancing investments. They have also forced farmers
to stop planting crops on marginal land.
At the same time, farmers in key food-producing regions were confronted
with some of the highest temperatures on record--temperatures that
stressed crops and reduced yields. The average global temperatures
for September and November 2001 were the highest ever recorded for
those two months in 134 years of recordkeeping. Then December, January,
February, April, and May posted their second highest temperatures
on record. And July 2002 was the fourth hottest ever. High temperatures
combined with low rainfall in many countries to create drought conditions.
Reports of heat-stressed crops have been common in the top three
food producers--the United States, India, and China. Even irrigated
crops suffer from high evaporation losses and heat stress. When
temperatures range above 32 degrees Celsius (90 degrees Fahrenheit),
crop yields can suffer.
The corn plant, a highly productive crop that accounts for 70 percent
of the U.S. grain harvest, is particularly vulnerable to heat. In
a heat-stressed field, leaves curl in order to reduce moisture loss
through evaporation. Under these conditions, photosynthesis declines
and the plant switches from a growth path to a survival mode, reducing
yields.
India's harvest has also suffered from high temperatures, including
a heat wave with temperatures reaching 45 degrees Celsius (113 degrees
Fahrenheit) in May that killed more than a thousand people. In addition,
this year's monsoon was late and weaker than normal. Less rainfall
has lowered India's estimated rice harvest from 90 million to 80
million tons.
Meanwhile, water tables are falling, as farmers pump more water
to meet the growing world demand for food. Water tables are now
dropping in key farming areas of China, India, and the United States.
In China, 70 percent of the grain comes from irrigated land. In
India, the figure is 50 percent, and in the United States, almost
20 percent.
USDA reports that in parts of Texas, Oklahoma, and Kansas, the underground
water table has dropped by more than 30 meters (100 feet). As a
result, farmers in some states in the southern Great Plains have
discovered their pumps are pumping air instead of water. Even states
like Nebraska and Colorado, where much of the corn is irrigated,
are facing poor harvests this year. (For additional examples of
falling water tables, see Eco-Economy Update "Water
Deficits Growing in Many Countries".)
Falling water tables are directly affecting harvests in scores of
countries, including, notably, that of wheat in China. After peaking
at 123 million tons in 1997, the wheat harvest there has fallen
in four of the last five years, coming in at 92 million tons this
year. Farmers in the northern half of China, where most of the wheat
is produced, depend on irrigation to supplement rainfall. When they
lose irrigation water from aquifer depletion, or the diversion of
water to cities, their yields drop. In the region around Beijing,
for example, farmers are banned from using the reservoirs since
all the water is needed to satisfy the city's fast-growing needs.
Can the world's farmers bounce back from an 83-million-ton deficit,
rebuild depleted stocks, and provide adequately for 80 million additional
people a year? In the past, higher grain prices have typically led
to an expansion of planted area and higher yields. How much more
the planted area can expand remains to be seen. After peaking in
1981 at 732 million hectares, the world grain area has fallen to
660 million hectares. The United States retired roughly 10 percent
of its cropland in the late 1980s under a Conservation Reserve Program
as farmers were paid to take highly erodible land out of production.
China is in the process of planting one tenth of its grainland to
trees during this decade as it tries to halt advancing deserts.
The one substantial remaining area of frontier expansion is in the
Brazilian cerrado, a vast semiarid, savannah-like region to the
south and west of the Amazon basin. But this land is of intermediate
fertility, requiring heavy applications of lime to reduce acidity
and of fertilizer to maintain the productivity of the leached soils.
Boosting land productivity is now much more difficult. In earlier
times, higher grain prices led to an expansion of irrigation, but
with aquifer depletion so widespread this does not seem likely.
Farmers also respond to higher prices by applying more fertilizer,
but with use already quite high, even in developing countries, it
is more difficult to expand fertilizer use profitably.
The world is now facing a challenging situation. It has been relatively
easy to recover from past annual harvest shortfalls of 20, 30, or
40 million tons. But with an 83-million-ton shortfall, recovery
may not be a simple proposition. If farmers are faced with even
higher temperatures in the years ahead, as projected, they may have
difficulty overcoming this year's huge shortfall, rebuilding stocks,
and providing for the 3 billion people to be added by 2050. Perhaps
now the world will give population growth and climate change the
attention these issues deserve.
See
Additional Data and Graph
Copyright
© 2002 Earth Policy Institute
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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, "Water Deficits Growing in Many
Countries: Water Shortages May Cause Food Shortages," Eco-Economy
Update, 6 August 2002.
Lester R. Brown, "World Grain Harvest Falling Short
by 54 Million Tons: Water Shortages Contributing to Shortfall,"
Eco-Economy Update, 21 November 2001.
Lester R. Brown, "Worsening Water Shortages Threaten
China's Food Security," Eco-Economy Update,
4 October 2001.
From Other Sources
Peter Gleick, The World's Water (Washington,
DC: Island Press, various years).
Sandra Postel, Pillar of Sand (New York:
W.W. Norton & Company and Worldwatch Institute, 1999).
Sandra Postel, Last Oasis: Facing Water Scarcity
(New York: W.W. Norton & Company and Worldwatch Institute, 1997).
LINKS
AQUASTAT, global information system of water and
agriculture from the Land and Water Development Division of the
U.N. Food and Agriculture Organization
http:/www.fao.org/
ag/agl/
aglw/aquastat/
main/index.stm
Goddard Institute for Space Studies, Surface Temperature
Analysis http:/www.giss.nasa.gov/
data/update/gistemp
International Water Management Institute
http:/www.iwmi.cgiar.org/
The World's Water
http:/www.worldwater.org
United Nations Environment Programme, UNEP Freshwater
Site
http:/freshwater.unep.net
United States Department of Agriculture (USDA) http:/www.usda.gov
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