After ten days of marathon meetings and late-night negotiations, agreement was reached and they finally put pen to paper. In the end, after 160 nations had wrangled, fought and played tug-of-war, they passed an important milestone by acknowledging a global threat and coming up with a global solution to protect the earth's environment.

This was different from Montreal when in 1987 representatives from all over the world had come together to ban CFCs. Carbon dioxide, methane and other greenhouse gases required a far grander and more monumental effort. This was a lot more than just swapping out the gas in the refrigerator. To control greenhouse gases required whole new technologies, whole new sets of tools and machinery, indeed a whole new lifestyle.

We create carbon dioxide with automobiles, industry, cooking fires, plows, axes - even out breath. We had to take a hard look at the cost of modern transportation. What price had the atmosphere paid for the increasing efficiency with which we moved our products to the market? What were the real costs of cutting down the rain forests in terms of climate change?

It seemed now that the world might finally be ready to do something about it. Though the scope of the agreement was limited, its mechanisms were important because it set standards for further agreements and created tactics from which the battle could be fought and hopefully won. It recognized that concentrations of certain greenhouse gases had been growing since the beginning of the Industrial Revolution and it recognized the international importance of reversing the steady increases.

The idea was that 38 nations needed to reduce their greenhouse gas emissions by an average of 2.5 percent below 1990 levels. In reality, the reductions were parceled out according to who emitted the most gases and who could afford the changeover. The United States would reduce emissions by 7 percent below 1990 levels, Japan by 6 percent and the European Union by 8 percent. The Russian Federation, Ukraine and New Zealand needed to return to 1990 levels, while Australia and Iceland has to stabilize their releases at 8 percent and 10 percent, respectively, above 1990 levels.

The European Union wanted to get started right away, but the United States pressed to have enforcement of the reductions put off until 2008. This would allow a full decade to allow governments and industries to gradually shift emphasis toward increasing energy efficiency: to upgrade pollution equipment as older machinery wore out, to switch from dirty fuels to cleaner-burning energy and the experiment with solar, wind and other alternative forms of energy.

Getting 160 nations to agree on something wasn't an easy task. European Union delegates has arrived with the ambitious of all industrial nations to cut their emissions by 15 percent below 1990 levels. It seemed easy for them to talk. The collapse of the former East German industries and a massive switchover in Great Britain from coal to natural gas during the 1990s had given Europe a head start on the rest of the world. But Europe relied heavily on emission-free nuclear power and nuclear power wasn't exactly squeaky clean.

But the real struggle was in the details. Japan insisted it wouldn't go any higher than 5 percent in emissions reductions. A 2 AM phone call from then vice president Al Gore to Prime Minister Ryutaro Hashimoto got Japan to up its ante. Gore argued that Japan couldn't wreck the chances to come to an agreement over a measly 1 percent. The Japanese Prime Minister relented.

The agreement placed limits on six greenhouse gases: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride. The European Union had wanted to limit the new curbs to just carbon dioxide, methane and nitrous oxide, but the United States succeeded in adding limits to the others. The later chemicals were arguably easier and cheaper to cut.