China's challenge to the United States and to the earth.

During the 1990s, China has emerged as an economic superpower, boasting the world's second largest economy. It is now challenging not only U.S. economic leadership, but the earth's environmental limits.

Using purchasing power parity to measure output, China's 1995 GNP of just over $3 trillion exceeded Japan's $2.6 trillion and trailed only the U.S. output of $6.7 trillion. If the Chinese economy continues to double every eight years, the pace it has maintained since 1980, it will overtake the United States by 2010, becoming the world's largest economy.

Over the last four years the Chinese economy has grown by 10 to 14 percent per year. As its population of 1.2 billion people moves into modern houses, buys cars, refrigerators and televisions, and shifts to a meat-based diet, the entire world will feel the effects. Already, China's rapidly rising [CO.sub.2] emissions account for one-tenth of the global total.

In recent decades, many observers noted that the United States, with less than 5 percent of the world's population, was consuming a third or more of its resources. But this is no longer true. In several areas, China has overtaken the United States. For example, China now consumes more grain and red meat, uses more fertilizer, and produces more steel than the United States.

Since China has 4.6 times as many people as the United States, its per capita demands on the earth's resources are still far less. To cite an extreme example, the average American consumes 25 times as much oil as the average Chinese citizen does.

Even with its still modest per capita consumption, China is already paying a high environmental price for its booming economy. Its heavy reliance on coal, for example, has led to air pollution nearly as bad as that once found in eastern Europe. As a result, respiratory disease has become epidemic in China, and crop yields are suffering.

As China, with its much larger population, attempts to replicate the consumer economy pioneered in the United States, it becomes clear that the U.S. model is not environmentally sustainable. Ironically, it may be China that finally forces the United States to come to terms with the environmental unsustainability of its own economic system. If China were to consume as much grain and oil per person as the United States does, prices of both commodities would go off the top of the charts. Carbon dioxide emissions would soar, leading to unprecedented climate instability. Together, these trends would undermine the future of the entire world.

The bottom line is that China, with its vast population, simply will not be able to follow for long any of the development paths blazed to date. It will be forced to chart a new course. The country that invented paper and gunpowder now has the opportunity to leapfrog the West and show how to build an environmentally sustainable economy. If it does, China could become a shining example for the rest of the world to admire and emulate. If it fails, we will all pay the price.

Grain Harvest: China

The United States, long the world's leading grain producer, was overtaken by China in 1983. Over subsequent years, the lead changed hands several times, but since 1986, China's grain harvest has usually exceeded that of the United States. It is also much more stable, because China has 2.5 times as much irrigated land as the United States. U.S. production of corn, which dominates U.S. agriculture, is largely rainfed and, affected by both heat and drought, it fluctuates widely from year to year. In consumption, the gap is far wider. China now consumes 365 million tons per year, and has become the world's second largest grain importer, whereas the United States consumes 200 million tons and remains the world's leading exporter.

Fertilizer Use: China

U.S. fertilizer use climbed rapidly from mid century onward. By 1980, it exceeded 20 million tons. Then it leveled off, averaging less in the mid-1990s than in the early 1980s. Meanwhile, in China, the 1978 economic reforms in agriculture led to a meteoric climb in fertilizer use. In 1986, China overtook the United States to become the world leader. In 1995, Chinese farmers used 28 million tons of fertilizer, while U.S. farmers used just under 20 million tons. In the United States, and now increasingly in China, fertilizer use is constrained by the physiological capacity of crop varieties to effectively absorb more nutrients.

Consumption of Red Meat: China

The consumption of red meat, particularly beef in the form of steak and hamburgers, has become a defining component of the U.S. lifestyle, but China's total consumption of red meat has eclipsed that of the United States. For all red meat combined - beef, pork, and mutton - China now consumes 42 million tons per year, compared with only 20 million tons in the United States. China's pork consumption of 30 kilograms per person matches the U.S. intake of 31 kilograms, but its beef consumption lags far behind 4 kilograms to 45 kilograms. If China were to close the beef gap, its people would eat an additional 49 million tons each year. Produced in feedlots, this would take some 343 million tons of grain - roughly as much as the entire U.S. grain harvest.

Automobile Production: United States

In the production of automobiles, the United States dwarfed China by some 6.6 million to 239,000 in 1995. U.S. output is not likely to increase much in the future, since most of the automobiles made now are used for replacement rather than for expanding the fleet. China, by contrast, plans to boost production to 3 million per year by the end of the decade, building a fleet of 22 million automobiles by the year 2010. If China's ownership of automobiles were to reach 1 for every 2 people, as in the United States, its fleet of 600 million cars would exceed the 1995 world fleet of 480 million cars.

Bicycle Production: China

If a crowded world is compelled to move toward a less polluting, less land consuming mode of personal transport, then the bicycle may well be the transport vehicle of the future. For this shift, China is well positioned. Its bicycle production has averaged over 40 million a year in recent years, compared with less than 8 million a year in the United States. This is perhaps the only major indicator for which the ratio of production between the countries reflects the ratio of population size. In global terms, China accounts for nearly two-fifths of world production of 110 million bicycles annually in recent years.

Steel Output: China

In the industrial world of an earlier era, steel production was perhaps the best single indicator of industrial progress. China has recently caught up with the United States in this industry, with both countries turning out 93 million tons in 1995. The big difference is that most of China's steel production is from iron ore. The United States, a more mature industrial society, now gets roughly half of its total steel from the reprocessing of scrap metal, a more energy-efficient, less polluting means of production. If China proceeds to develop an automobile-centered transportation system as currently planned, its steel needs will soar far beyond those of the United States.

Oil Use: United States

Despite its booming economy, China still consumes only 3.3 million barrels of oil each day, one-fifth the 17 million consumed daily in the United States. U.S. oil use per person is a striking 25 times that in China. With its limited oil reserves, China relies on coal for 75 percent of its energy, whereas the United States relies on coal for just 22 percent. But as China becomes more dependent on automobiles and trucks, its oil use is climbing. Already, it has gone from exporting 500,000 barrels of oil per day in 1990 to importing 300,000 barrels per day in 1995. If China were one day to use as much oil per person as the United States does, it would need 80 million barrels daily - more than the whole world now produces or is ever projected to produce.

Carbon Emissions: United States

Carbon emissions from fossil-fuel burning totaled 1.394 million tons in the United States in 1995, 73 percent higher than the 807 million tons emitted by China. Fossil fuel burning releases carbon dioxide into the atmosphere - the main gas leading to greenhouse warming. Since 1990, U.S. carbon emissions have grown at roughly 1 percent per year while China's grew at 5 percent annually as use of coal and oil surged. Even so, the United States still emits eight times as much carbon per person as China. If China develops the sort of energy-intensive industries and lifestyles found in the United States, it would further destabilize the world's atmosphere.

Computer Power: United States

If steel production is a key indicator of progress in an industrial society, computer use is a key indicator in the information economy of the late twentieth century. In this area, there is no contest: the United States has one computer for every three people; China has one for every 1,000 people. With 74 million computers out of a worldwide total of 173 million, the United States leads the world by a wide margin in the computerization of its economy. China, which has just 1.2 million computers, lags far behind not only the United States but much of the rest of the world as well.