It takes 1,000 tons of water to produce 1 ton of grain. As water becomes scarce and countries are forced to divert irrigation water to cities and industry, they will import more grain. As they do so, water scarcity will be transmitted across national borders via the grain trade. Aquifer depletion is a largely invisible threat, but that does not make it any less real.

Socialism failed because it couldn't tell the economic truth. Capitalism may fail because it couldn't tell the ecological truth.

We are witnessing the beginning of one of the great tragedies of history. The United States, in a misguided effort to reduce its oil insecurity by converting grain into fuel for cars, is generating global food insecurity on a scale never seen before.

The problem with water, though, is that the shortfalls don't show up until the very end. You can go on pumping unsustainably until the day you run out. Then all you have is the recharge flow, which comes from precipitation. This is not decades away, this is years away. We're already seeing huge shortages in China, where the Yellow River runs dry for part of each year. The Yellow River is the cradle of Chinese civilization. It first failed to reach the sea in 1972, and since 1985 it's run dry for part of each year. For 1997 it was dry for 226 days.

The 20th century was the time when the world turned to use of fossil fuels and the 21st century will be the century of the renewables.

Humanity's greatest challenge may soon be just making it to the next harvest.

The foundation is being laid for the emergence of both wind and solar cells as cornerstones of the new energy economy. World wind generating capacity grew from 7,600 megawatts in 1997 to 9,600 in 1998, an expansion of 26 percent. At a national level, Germany led the way, adding 790 megawatts of capacity, followed by Spain with 380 megawatts, and the United States with 226 megawatts. In the past, U.S. wind generating capacity was concentrated in California, but in 1998, wind farms began generating electricity in Minnesota, Oregon, and Wyoming, broadening the new industry's geographical base.