Each summer, for example, nitrogen and phosphate washing from farmlands in the Mississippi Valley enter the Gulf of Mexico, creating a massive algal bloom covering some 16,000 square kilometers. As the blooms die off, this area-roughly the size of New Jersey-is so deprived of oxygen that no fish survive.

The transition from coal, oil, and gas to wind, solar, and geothermal energy is well under way. In the old economy, energy was produced by burning something - oil, coal, or natural gas - leading to the carbon emissions that have come to define our economy. The new energy economy harnesses the energy in wind, the energy coming from the sun, and heat from within the earth itself.

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.

In Mexico City, Tehran, Kolkata, Bangkok, Shanghai, and hundreds of other cities, the air is no longer safe to breathe. In some cities, the air is so polluted that breathing is equivalent to smoking two packs of cigarettes per day.

Today, more than ever, we need political leaders who can see the big picture, who understand the relationship between the economy and its environmental support systems.

Rising oil prices have focused the world's attention on the depletion of oil reserves. But the depletion of underground water resources from overpumping is a far more serious issue. Excessive pumping for irrigation to satisfy food needs today almost guarantees a decline in food production tomorrow.

One way or another, the choice will be made by our generation, but it will affect life on earth for all generations to come