No longer a debate

Climate change discussion shifts from 'Is it real?'to how science & technology can help us deal with it

This article appears in an upcoming ORNL Reporter newsletter. For more information on ORNL and its research and development activities, please refer to one of our Media Contacts.

	The Northwest Passage, seen running vertically at center right, was ice-free for the first time in history last September. In this polar perspective, the North Pole is roughly where the X is; Greenland's southern tip points up..

What a difference a few years make.

For example, in March 1993 the "storm of the century" buried parts of the Tennessee Valley in more than a foot of snow. It's hardly snowed in the valley since.

Not that long ago, the question was whether the climate was really changing, and the arguments were often politically charged. That debate has largely shifted in recent years, or even months, to what can be done in the face of warming global temperatures.

As this article was being written, a March-like cold front, complete with tornadoes that hammered the western part of the state, made its thundery way through the area. Except it was only the first week of February.

"Climate change is no longer an issue for debate. The climate is indeed changing," says Tom Wilbanks, the Environmental Sciences Division senior scientist and corporate fellow. "And human forces are at least one of the drivers."

Tom's conclusions aren't based simply on harkening back to the last hard winter. As a geographer and environmental scientist who has served as a contributing lead author for the United Nations' Intergovernmental Panel on Climate Change, he has studied the research data that project a considerable change in the world's climate, along with widespread impacts.

The main driving force, Tom says, is the progress of civilization and its dependence on carbon. Since the nineteenth century's Industrial Revolution, carbon locked in the ground since the lush and swampy Carboniferous Period has been released through the combustion of coal, oil and natural gas. Elevated atmospheric carbon is one down side of the astounding technological boom of the last century, particularly since the advent of the internal combustion engine and the electric grid.

Most of that released carbon is in the form of carbon dioxide which, although it represents a small portion of the earth's atmosphere, is very effective at trapping heat-a so-called greenhouse gas.

The affluence spawned by humankind's adeptness at putting energy to work, until recently the Western World's private party, has in recent decades spread to other populous regions of the globe, including China and India. With that economic growth comes a commensurate increase in carbon dioxide in the atmosphere.

"Impacts cannot be avoided," Tom says, with a calculated abruptness. He doesn't mince words on this topic.

"In the time between the [IPCC] panel's third assessment and fourth assessment, we've seen the impacts emerge much more rapidly than even we had predicted," he says, "and our ability to adapt to them is questionable in many areas."

Greenhouse gases, which increased at a rate of 1.3 percent per year in the 1990s, have been racing up at a rate of 3 percent per year during this decade, more than doubling in their rate.

Tom anticipates the next question: Why worry? The sorts of scenarios that former Vice President Al Gore painted in An Inconvenient Truth may lie ahead, he says, with flooded coastlines, parched croplands, altered ecosystems and skewed economies.

To really hit home, imagine summer heat indexes of 115 degrees on the golf course. If trends continue, duffers won't have to imagine them for very much longer.

Or you will be able to sail a ship through an ice-free Northwest Passage. For the first time in history. That's the scale of the change that is under way.

"Business as usual would clearly be catastrophic in many ways," Tom says.

Arriving at policies toward curbing the emission of carbon into the atmosphere has been shown to be politically and economically difficult. Stabilizing CO2 concentrations in the lower bounds of what is desirable-say, 550 parts per million or less-now appears to be unachievable. A level of 650 to 850 ppm is more likely, which would cause "catastrophic impacts in some areas."

The argument over whether climate change is in fact real has segued into the debate over what it all means and how, or if, societies and economies can adapt to the changes.

Tom was coordinating lead author for one of the U.S. Climate Change Program's recently published synthesis and assessment products, which for the first time analyzed the effects climate change will have on U.S. energy production and use. The conclusions range from the common-sensical (less energy spent on heating, more spent on cooling) to the more indirect effects, such as how warmer air and water temperatures could make power plants less efficient and how water scarcity could add to the cooling challenge.

On the other hand, the growing consumption that is stoking atmospheric CO2 is also driving energy prices higher, which could help inspire R&D in energy technologies that would reduce carbon emissions. That should be happening sooner rather than later.

"The institutions in this country have both the financial power and human resources to respond. There is time to adapt if we take the risks and vulnerabilities seriously in the long run," Tom says.

But "the world's climate in 2080 depends on emissions in 2030. Technology needs to be developed now; we've got to move fast if we are going to have the breakthroughs that can make a difference by the end of the century," he says.

The senior corporate fellow's stance on the topic of climate change has raced past the debate stage, just as the winds of public opinion have shifted enough to acknowledge the urgency of the matter.

"The time to act is now," he says.