President Bush’s offer this week to further study climate change rather than do something about it looks a lot like President Bush’s offer made in 1990 to study climate change. The difference between the son’s offer and the father’s, however, is that a decade ago there was legitimate uncertainty on the issue that outweighed the understanding of it. Now, the reverse is true, and the time to act has arrived.

The president’s itinerary in Europe this week carefully skips countries that are most unhappy with his position on global warming, but he is hearing from protestors anyway on this and other points of disagreement. The Europeans want the United States to adopt the Kyoto Treaty, which would reduce some pollutants to 1990 levels. President Bush said early this week that he would not agree to such standards while countries such as China and India are allowed to ignore them.

This stance is misguided for a couple of reasons. The United States pollutes, per capita, at 10 times the rate of China and 20 times the rate of India, and China in the last 10 years has reduced emissions voluntarily more than the United States has, making some manufacturing processes there now more efficient than here. Further, the Kyoto Treaty intentionally required the wealthier nations, responsible for 75 percent of greenhouse emissions, to take the lead because they had more capacity to make changes and could more easily develop new technologies that would result in less pollution worldwide.

That has happened in Europe, which, like the United States, produces approximately 20 percent of the world’s gross product, according to Norbert Walker, chief economist of the Deutsche Bank Group in a recent commentary. But unlike the United States, Europe does it by consuming 16 percent of the world’s energy, compared with 25 percent here, leaving the United States as the biggest producer of carbon dioxide emissions from burning fossil fuels in vehicles, power plants and other industries.

The lack of will to require U.S. manufacturers to become more efficient not only is costly in the long term to the makers and buyers of goods, but is a principal reason that European protesters are irritated with the United States, making agreement on other issues more difficult. It is also unnecessary, given the chasm between where the president stands on climate change and the treaty. With his own new study from the National Academy of Science concluding that greenhouse gases are accumulating in the Earth’s atmosphere as a result of human activity and the earful he is getting in Europe, the president could propose three relatively modest initiatives to move the United States away from just more studies and into action.

. He should reverse his decision to lower efficiency standards on household appliances such as air conditioners and set standards for more energy efficient houses generally.

. He should support the measures in Congress to include sport-utility vehicles in fuel-efficiency standards and then set new, tougher targets for these standards.

. He should accept the recommendation from eight major utilities and return to his campaign pledge to reduce emissions from power plants, encouraging the use of natural gas over coal.

No one doubts the need to further study climate change or that what is believed today will be modified in some way as more is learned. But enough is known now for the United States to join much of the developed world in reducing the pollutants that are changing the environment in ways that are likely to cost nearly everyone dearly in the near future.