As Americans celebrate Thanksgiving and another bountiful harvest, there are signs that the world harvest is falling short as water shortages translate into food shortages. In its November world crop survey, USDA reports that this year's estimated world grain harvest of 1,841 million tons will fall 54 million tons short of projected consumption of 1,895 million tons. This comes on the heels of a poor crop last year, when world output fell short of use by 34 million tons.

These two consecutive disappointing harvests have reduced next year’s projected world carryover stocks of grain, the amount in the bin when the new harvest begins, to 22% of annual consumption, the lowest level in 20 years. With stocks at such a low level, all eyes will be on the harvest in 2002. Another short harvest could lead to rising grain prices and higher prices for bread, meat, milk, eggs, and other products derived directly or indirectly from grain.

The poor harvests of the last two years were largely due to weak grain prices, drought, and spreading water shortages. The lowest grain prices in two decades have discouraged farmers from investing in production-boosting measures.

Prices too low to stimulate adequate production can be quickly remedied as the market responds to tighter supplies. But dealing with water shortages that result from drought, aquifer depletion, and the diversion of scarce water to cities is much more difficult.

Water tables are now falling in key food-producing regions – the North China Plain, the Punjab in India, and the southern Great Plains of the United States. The North China Plain accounts for a third of China’s grain harvest. The Punjab, a highly productive piece of agricultural real estate, is India’s breadbasket. And the southern Great Plains help make the United States the world’s leading wheat exporter.

In an increasingly integrated world economy, water shortages are crossing national boundaries via the international grain trade. Since it takes 1,000 tons of water to produce 1 ton of grain, the most efficient way for water-deficit countries to import water is to import grain.

The fastest-growing grain import market in the world today is North Africa and the Middle East, the region with the most serious water shortages. Virtually every country in this region – stretching from Morocco across the northern tier of Africa and the Middle East through Iran – is facing water shortages. With supplies limited, countries satisfy the growing demand for water in cities and industry by taking it from agriculture. Then they import grain to offset the loss of production capacity.

It is often said that future wars in this region are more likely to be fought over water than oil. This may be, but it is hard to win a water war. The competition for water is more likely to take place in world grain markets.

In recent years, grain imports into Iran, a water-short, grain-deficit country, have eclipsed those of Japan, long the world’s leading wheat importer. Last year, Egypt also moved ahead of Japan. Both Iran and Egypt now import over 40% of the grain they consume. The populations of both countries are continuing to grow, but their water supplies are not.

Grain exporters are, in effect, water exporters. Canada, where water exports are a politically sensitive issue, is one of the world’s leading exporters of water in the form of grain. The 18 million tons of grain, mostly wheat, that it ships abroad each year embody 18 billion tons of water. Similarly, U.S. annual grain exports of 90 million tons of grain represent 90 billion tons of water, an amount that exceeds the 67-billion-ton annual flow of the Missouri River.

The adequacy of food and water supplies are closely linked. Some 70% of all water that is pumped from underground or diverted from rivers is used to produce food, while 20% is used by industry and 10% goes to residential uses. With 40% of the world’s grain harvest produced on irrigated land, anything that reduces the irrigation water supply reduces the food supply.

The wildcard in the world grain market is China. It accounted for 45 million tons of this year’s grain harvest shortfall of 54 million tons. Last year, China’s harvest fell short of consumption by 33 million tons. In two years, it has reduced grain stocks by nearly 80 million tons.

Among the forces shrinking China’s grain harvest are severe drought in northern China during the last two years, spreading irrigation water shortages as aquifers are depleted and as water is diverted to cities, and a lowering of support prices. The drought will eventually end, but water shortages will not. In a country dependent on irrigated land for 80% of its grain, water shortages are fast becoming a security issue. (See Eco-Economy Update "Worsening Water Shortages Threaten China’s Food Security,"

In 1994, in an ambitious and successful effort to be self-sufficient, China raised grain support prices by 40%. Unfortunately, the drain on the treasury was too great, so the support prices were lowered, dropping close to world market levels. As grain prices have fallen over the last three years, the area planted to grain has shrunk by 10%.

China has absorbed the harvest shortfall of the last two years by drawing down stocks, but there are signs that supplies are now tightening. If this huge nation has another large harvest shortfall, it will likely have to import substantial quantities of grain to maintain food price stability. China, with a population equal to that of India and the U.S. combined, has a strong economy and a trade surplus with the U.S. of over $80 billion. It would take only $35 billion of that trade surplus to buy the entire U.S. grain harvest. China can compete not only with the 100 or so countries that import U.S. grain, but with U.S. consumers if it needs to.

If the 2002 world grain harvest falls short of consumption when stocks are at a near-record low, prices will rise. Higher prices will curb demand, particularly the feeding of grain to livestock, and will encourage production. Supply and demand will again be in balance, but at a higher price.

If world grain demand continues to grow during this coming year at the 16-million-ton-per-year pace of the last decade, then the harvest will have to jump by 70 million tons to avoid a further drawdown in stocks. Whether this can occur, in the face of spreading water shortages, remains to be seen.

As water deficits expand in water-scarce countries, so too will grain deficits. The new reality is that if the world is facing water shortages, it is also facing food shortages.

Another troubling reality: Most of the 80 million people being added to world population each year are being added in countries that are already experiencing water shortages. Restoring a balance between water supply and needs worldwide may now depend on stabilizing population in water-deficit countries.