The Kyoto Protocol on climate change takes effect Wednesday after more than seven years of difficult and complex negotiations aimed at reducing emissions of carbon dioxide (CO2) and other greenhouse gases. Perhaps future generations will remember Feb. 16, 2005, as the day the world launched a determined drive to reverse the potentially calamitous trend of global warming.

The protocol, adopted in Kyoto in late 1997 by signatories to the U.N. Framework Convention on Climate Change, sets binding numerical targets for industrialized nations' output of CO2 and other heat-trapping gases. The Kyoto agreement is testimony to the growing realization in the world that the traditional patterns of energy production and consumption must change.

Since the Industrial Revolution, fossil fuels -- oil and coal in particular -- have driven the engine of economic growth, but in the process they have released enormous quantities of CO2 into the atmosphere. The increasing threat of global warming -- now widely recognized -- makes it imperative to reduce CO2 emissions on a sustainable basis. The finiteness of underground energy resources also makes it essential to create a more energy-efficient society.