Living in the Greenhouse

By ANDREW C. REVKIN

EUREKA moments are rare in science. Achievements like the deduction of DNA's structure etch our imagination precisely because they are exceptional. In most fields, research is more akin to climbing a mist-shrouded mountain of unknown dimensions. Climate science, perhaps above all, has been a perpetual ascent toward understanding. A major achievement so far is a broad consensus that beginning in the industrial era humans, by burning ancient buried stores of carbon-rich coal and oil, have liberated billions of tons of heat-trapping greenhouse gases, warming earth.

Debate persists over the extent of human-driven warming and what to do about it. But recognition that in a short span our species has nudged the thermostat of a planet remains a momentous, and sobering, finding.

''The Discovery of Global Warming'' describes the intellectual journey toward that conclusion, with all of its false starts, flawed hypotheses, inventiveness and persistent uncertainties. It reveals the effort as one of the great exercises in collective sleuthing, with pivotal insights provided by experts in fields as varied as glaciology, physics and even plankton paleontology. Charting the evolution and confirmation of the theory, Spencer R. Weart, director of the Center for the History of Physics of the American Institute of Physics, dissects the interwoven threads of research and reveals the political and societal subtexts that colored scientists' views and the public reception their work received.

In many instances, he writes, researchers were pursuing knowledge for other purposes and only later were their data used to determine if humans had influenced the climate. He notes that much of the oceanographic and polar research that eventually helped point to human-driven warming was paid for by the United States Navy and other government agencies that were eager to exert American hegemony during the cold war.

The narrative starts with the 150-year-old notion that some trace gases are transparent to sunlight but opaque to infrared radiation, the radiant energy that pulses from a sun-warmed sidewalk long after dusk. This insulating property of the atmosphere prevents the planet from turning into an iceball. Weart uses excerpts from pivotal papers to let us glimpse the thinking of climatology's pioneers. Thus, in 1862, John Tyndall, a British researcher, wrote about infrared radiation, ''As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown as a barrier across the terrestrial rays, produces a local heightening of the temperature at the earth's surface.''

As the Industrial Revolution accelerated, scientists soon figured out that emissions of heat-trapping gases from burning coal and other fossil fuels might intensify that natural ''greenhouse effect.'' Chief among these gases was carbon dioxide. One omission from Weart's book is a prescient phrase written in 1896 by Svante Arrhenius, a pioneering Swedish chemist: ''We are evaporating our coal mines into the air.''

Still, the human contribution to climate was presumed to be far outweighed by the great cycles of ice ages revealed in fossil and geological records. The puzzle of those cycles remained the prime quarry of Arrhenius and others and has still not been completely solved.

A warm period in the 1930's brought the first specific predictions that humans could alter the climate, but then things cooled down for a few decades and the possibility of a human influence remained a fringe notion. (Later, Weart explains, it was shown that the temporary cooling could also have been caused by humans -- through the release of vast sun-reflecting plumes of sulfates and other tiny pollution particles in the industrial boom after World War II: one human emission was canceling out another until clean-air laws began removing the cooling veil.)

Weart next focuses on the great burst of geophysical research starting in the 1950's, when data started showing for the first time that humans were indeed changing the atmosphere. He describes how individual scientific obsessions, like Charles David Keeling's preoccupation with creating a precise record of carbon dioxide concentrations, produced vital puzzle pieces.

To be continue in other article...

(Jakarta, Senin 19 February 2008, 10.32 pagi)

Re-publish by Jacob Paradox from link (www.nytimes.com)

Project to Capture CO2

With Plankton Puts to Sea

By Andrew C. Revkin

The WeatherBird II is part of a project aimed at encouraging plankton growth.

(Credit: Jay Paul for The New York Times)

The WeatherBird II, a 115-foot private research vessel, has put to sea from Florida as part of a novel and contentious effort to commercialize the removal of heat-trapping carbon dioxide from the atmosphere by triggering blooms of plankton.

The ship is operated by Planktos, one of a host of companies involved with the fast-growing global market in “carbon offsets,” credits bought by individuals or companies seeking to compensate for carbon dioxide emissions from flying, electricity use or other energy-intensive activities.

The WeatherBird II entered international waters on Sunday, said Russ George, the chief executive of Planktos, based in Foster City, Calif. Plankton blooms happen naturally when dust containing iron settles on ocean waters where a lack of iron otherwise prevents plankton from thriving. But efforts to replicate the process artificially have met with strong opposition from some environmental groups.

These include the Sea Shepherd Conservation Society, which for years has confronted, and sometimes rammed, whaling and fishing vessels. It had also planned to try to block a fertilization effort by Planktos this summer near the Galapagos Islands, but the company delayed that project for a variety of reasons, officials said. Ocean fertilization is one strategy scientists are mulling to blunt the unrelenting growth in carbon dioxide emissions from smokestacks, tailpipes and deforestation.

A natural phytoplankton bloom in the Bering Sea. (Credit: NASA) Some scientists have estimated that hundreds of millions of tons of carbon dioxide might be absorbed by fertilized seas, particularly in regions low in iron.

But others say much more research should be conducted before commercial-scale operations begin. Among various questions, scientists have yet to determine how much of the carbon captured by plankton blooms through photosynthesis sinks to the seabed and how much is re-emitted to the atmosphere as carbon dioxide or other greenhouse gases.

This year, the president of Friends of the Earth, Brent Blackwelder, issued a statement saying, “Planktos is selling the equivalent of global warming snake oil.” In an e-mail exchange Tuesday night, Mr. George declined to discuss the route of the WeatherBird II or whether a second ship will join it to distribute tons of iron-containing dust, because of what he said were continuing threats. Concerns about environmental impacts have no merit, he said, adding that the project was precisely the kind of work that could help answer lingering questions about the method.

“We have requests and offers from governments and scientists all over the world to send teams aboard to actively participate,” Mr. George said. “However, all those working with us who have been revealed in public have been ruthlessly attacked and threatened for helping Planktos do credible, transparent, verifiable science.”

[UPDATE: An Australian company with a different technique for boosting plankton growth — adding urea to the sea — has evidently gained permission from the Philippines to do a field test in the Sulu Sea, raising objections from some private groups and blogger.]

What kinds of private-sector experiments to limit the buildup of greenhouse gases do you feel are justified, given the limits of government-supported research?

To be continue in other article...

(Jakarta, Senin 19 February 2008, 10.32 pagi)

Re-publish by Jacob Paradox from link (www.nytimes.com)