Update 16: 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
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.
Copyright © 2002 Earth Policy Institute
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