MB Civic

By JACK ROSENTHAL

Though firmly rooted on Eighth Avenue, the new New York Times tower will be able to move its eyes. When it opens next spring, the 52-story structure will respond to hourly and seasonal variations in brightness. It will incorporate various kinds of insulation, like the horizontal ceramic rods spaced across many windows to create a permanent light screen. Equally important, shades, lighting and heating will adjust automatically to the amount of sunshine streaming in. Not insulation but insolation.

That’s the scientific term for the amount of solar radiation that reaches a given point on earth, measured by the number of watts per square meter. When that number goes up in the new Times building, energy use will go down. The Times Company expects to save 50 percent on lighting costs alone.

Insolation. It’s one of a wave of environmental words surging into popular usage about as fast as rises in the price of gasoline. In his new film and book, “An Inconvenient Truth,” Al Gore defines many such terms, relating mainly to climate change. Dozens more describe other issues, like the interconnection between human and animal health.

For instance, consider the term positive feedback, which is not necessarily positive at all. The Gore book gives a powerful example. When Arctic ice melts, the vast white sheets that reflect the sun’s heat dissolve into dark water. The water absorbs the sun’s heat, causing more melting causing more dark water causing more global warming and on and on.

Meltwater on thick ice creates deep crevasses called moulins, as in the French word for mills. The water plunges deep through them. “When the water reaches the bottom of the ice,” Gore writes, “it lubricates the surface of the bedrock and destabilizes the ice mass,” which is then at risk of crashing into the ocean and raising the sea level.

A similar climatic consequence also occurs on terra firma, when the clearing of rain forests changes the albedo, a measure of reflectiveness, and causes more heat to be absorbed as the sun strikes the dark soil.

President Bush described, though did not actually pronounce, another emerging term, cellulosic ethanol, in his State of the Union address. It is fuel made from plant residues, using what he called “cutting-edge methods of producing ethanol, not just from corn, but from wood chips and stalks or switch grass.” Biomass is another, easier way to say the same thing.

Just as more ice in the water can warm global temperature, so do more particulates, tiny particles of solid or liquid, in the air. They can be man-made or natural. Their radiative forcing can affect the climate by changing the way heat is absorbed — or reflected — in the atmosphere.

Meanwhile, tiny particulates can also have pronounced human health effects. Molecular epidemiology is a new field of science that studies such risk factors and looks for ways to prevent them.

The potential for an avian flu epidemic has focused worldwide attention on the relationship between diseases of wild animals, domestic animals and human health. Human diseases that originate in animals are zoonoses (pronounced zoh-ON-uh-seez). One of these is H.I.V., which started as S.I.V., the simian immunodeficiency virus. Mary Pearl, president of the Wildlife Trust, says she believes that the most likely route of transmission to humans involved the blood of hunted animals.

The increasing use of such terms reflects growing concern about environmental threats, but it also has a positive dimension. Understanding what to call a problem is the first step toward responding to it and away from insulating ourselves against its consequences.