A long-simmering debate has come to a boil among climate policy specialists over the most effective way to ensure humanity has the necessary hardware it needs to reduce greenhouse-gas emissions to virtually zero over the course of this century.
At issue is whether the current tack on climate policy, which emphasizes the establishment of binding emissions goals, should take a back seat to an all-out push to develop the technology needed to accomplish that feat.
Politicians are more likely to back tight emissions targets if the tools to meet them are readily at hand, proponents of a technology-first approach argue.
"This is one of the two or three central debates in the climate issue," says Joseph Romm, a senior fellow at the Center for American Progress in Washington and a top US Energy Department official during President Clinton's second term.
The trigger for the flare-up is a critique issued Thursday that attempts to show that the UN's Intergovernmental Panel on Climate Change has significantly understated the technology challenge the world faces on climate change. It does so, the argument goes, by overestimating the pace at which less carbon-intense and more energy-efficient technologies take root naturally as economies evolve.
Given the twin demands of controlling climate change and ensuring the world's future energy needs are met, "the first question to ask is not 'how do we reduce emissions?' " says Roger Pielke Jr., a science-policy specialist at the University of Colorado at Boulder, the author of the critique. Instead, he says, the question should be: "In a world that needs vast amounts of more energy, how can we provide that energy in ways that do not lead to the accumulation of carbon in the atmosphere?"
Technologies that are already at hand or likely to go commercial over the next decade may not be climate friendly enough to stabilize atmospheric greenhouse-gas concentrations so that global warming is held to about 3.6 degrees Fahrenheit by century's end. At this stage, he says, people should focus more on policies that directly address what many analysts see as a yawning technology gap, rather than on regulatory approaches that deal with the gap less directly.
The critique by Dr. Pielke and colleagues at the National Center for Atmospheric Research in Boulder, Colo., and McGill University in Montreal, has touched off a small firestorm among the scientific community – in no small part because it appeared in the pages of Nature, one of the most high-profile science journals on the planet.
Some of the reaction to the critique focuses on the nuts and bolts of the argument, which implies that when the IPCC lays out emissions projections, it might do better to assume that technologies don't get much better over time. That would give a clearer sense of the challenge ahead than assuming – as they argue the IPCC does now – that anywhere from half to virtually all of the technology gap could close in the course of ordinary economic evolution.
"That's an old game I've seen for 20 years," says Henry Jacoby, co-director of the Joint Program on the Science and Policy of Global Change at the Massachusetts Institute of Technology. In basing their analysis on frozen technologies, Pielke and his colleagues offer up futures "that are not going to exist." Rising energy prices, shifts away from energy intensive industries toward service- and information-based economies, and unforeseen applications of new technologies historically have combined to squeeze more energy out of existing sources, as well as trigger alternatives. There's no reason to think that won't continue, Dr, Jacoby says.
Other critics say a technology-first approach implies delaying action until it's too late. Future technologies "are irrelevant if you don't reverse course now" by "putting the pedal to the metal and deploy every last bit of technology we have today nationally and globally," says Dr. Romm.
How the debate has transformed
In many ways, the growing profile of this debate may not be so much because it's new but because it's one of the last disagreements standing on climate change. Discussions are shifting from drawn-out broadsides over whether human-triggered global warming is a problem and toward crafting the policy and technology tools to meet climate needs without undercutting economic growth, particularly in developing countries.
The shift has been prompted not only by recent evidence of how climate has changed over the long term and the speed of recent changes, but by the growth in greenhouse-gas emissions as developing economies in China, India, and other countries take off.
According to the IPCC, atmospheric concentrations of carbons need to be stabilized at levels that hold global warming to 3.6 degrees F., the maximum temperature required to stave off the worst effects of warming. To do this, many researchers say emissions must peak between 2015 and 2020 then quickly begin to fall.
Others, such as the National Aeronautics and Space Administration's James Hansen, now argue that to avoid the worst global warming can bring, the long-term temperature stabilization goal needs to be even lower.
Yet for all the thunder and fury the latest critique has generated, there is broad agreement that countries are falling far short of using the tools available, given the brief time for action – at least in political terms – that the latest IPCC reports imply. From environmentalists such as Lester Brown, who heads the Earth Policy Institute in Washington to economists such as Jeffery Sachs, who heads Columbia University's Earth Institute, there is a consensus that far more needs to be done to expand the use of current and foreseeable technologies, as well as enlisting labs worldwide in a broad hunt for new generations of technologies.
Some put it in terms of establishing the equivalent of the Manhattan Project; others call for a level of focused investment comparable to what is spent on the National Institutes of Health.
Yet the magnitude of the technological challenge should not be reason for despair, analysts say. "It seems to me that we're not stuck with no place to turn," says Dr. Sachs.