For more than 40 years, earth has been sending out distress signals. At first they were subtle, like the thin shells of bald-eagle eggs that cracked because they were laced with DDT. Then the signs were unmistakable, like the pall of smoke over the Amazon rain forest, where farmers and ranchers set fires to clear land. Finally, as the new millennium drew near, it was obvious that Earth's pain had become humanity's pain. The collapse of the North Atlantic cod fishery put 30,000 Canadians out of work and ruined the economies of 700 communities. Two years ago, deforestation worsened China's floods, which killed 3,600 people and left 14 million homeless. Population pressures and overcrowding raised the toll from last year's rains in Latin America, which killed more than 30,000 people and created armies of environmental refugees.

And how have we responded to four decades of ever louder distress signals? We've staged a procession of Earth Days, formed Green parties, passed environmental laws, forged a few international treaties and organized global gabfests and photo ops like the 1992 Earth Summit in Rio de Janeiro. All the while, the decline of Earth's ecosystems has continued unabated.

What will it take for us to get serious about saving our environment? When will environmentalism move from being a philosophy promoted by a passionate minority to a way of life that governs mainstream behavior and policy? How can we understand that Earth is one big natural system and that torching tropical rain forests and destroying coral reefs will eventually threaten the well-being of towns and cities everywhere?

One crucial step is a true accounting of the state of the planet, a thorough assessment of the health of all Earth's major ecosystems, from oceans to forests. Only a comprehensive global survey can show how damage to one system is affecting other systems and can determine whether Earth as a whole is losing its ability to nurture the full diversity of life and the economies of nations. That was the thinking behind the launching of the most ambitious study of global ecosystems ever undertaken. In September, at a special millennial session of the U.N., four of its agencies and partners—the World Bank, the U.N. Development Program, the U.N. Environment Program and the World Resources Institute—will present the first results of this project, a Pilot Analysis of Global Ecosystems. The findings of the $4 million study, called PAGE for short, will be published in the 2000-01 edition of the World Resources Report titled People and Ecosystems: The Fraying Web of Life. PAGE will also set the stage for a larger $20 million Millennium Ecosystem Assessment, scheduled to begin next year. The goal is to answer the most important question of the century: What is happening to Earth's capacity to support nature and civilization?

Time was given an exclusive advance look at the U.N. report, which makes for sobering reading. Its conclusions are divided into assessments of five major types of ecosystems—forests, freshwater systems, coastal/marine habitats, grasslands and agricultural lands—and all five are showing signs of deterioration (see the graphics on these PAGEs). The report's maps and charts capture the stunning scale and character of human impact on the planet. One set reveals the degree to which agricultural lands have been degraded around the world by the buildup of salts and the loss of nutrients; another locates oceanic dead zones caused by pollutants flowing to the sea from rivers; another shows the degree to which productive parts of the sea floor have been destroyed by trawling; another highlights how much humanity has altered coastlines. Many of the statistics are staggering: half the world's wetlands have been lost in the past century; 58% of coral reefs are imperiled by human activity; 80% of grasslands are suffering from soil degradation; 20% of drylands are in danger of becoming deserts; and groundwater is being depleted almost everywhere.