WASHINGTON -- It would be healthy -- in the sense of promoting honesty -- if every report warning of global warming and climate change (the two terms are interchangeable) came with the following disclaimer:
Despite our belief that global warming poses catastrophic threats to many of the world's 7 billion inhabitants, we acknowledge that we now lack the technologies to stop it. The purpose of our analysis and policy proposals is to create the political and economic conditions that foster the needed technologies. But there is no assurance that this will happen, and much time and money may be invested in futile and wasteful efforts.
I am not optimistic. Our climate-change debates confuse more than they clarify. They follow a ritualistic script that is now playing out again.
First came a downbeat report from the Intergovernmental Panel on Climate Change (IPCC), an international group of scientists set up by the United Nations. It found that global temperatures have warmed for decades, that man-made emissions are the main cause (atmospheric concentrations are said to be the highest in 800,000 years) and that the effects include rising sea levels, melting ice packs and more heat waves.
Next arrived the U.S. National Climate Assessment, a study by 300 American experts that's more alarming than the IPCC report. It begins: "Climate change, once considered an issue for a distant future, has moved firmly into the present." Americans already suffer from global warming. Floods are more frequent; wildfires are harder to control; rainstorms are more violent.
Naturally, climate skeptics (aka, "deniers") denounced the reports. The evidence was exaggerated, cherry-picked or both, said Paul Knappenberger and Patrick Michaels of the Cato Institute, a libertarian think tank. Consider, they said, a contrasting study headed by a Harvard researcher. It found that heat-related deaths in 105 U.S. cities had declined since the late 1980s.
The rhetorical ping-pong -- claim vs. counterclaim -- suggests a struggle for public opinion. Not really. Right or wrong, the public already believes in global warming. A 2013 Pew poll found that 67 percent of Americans see "solid evidence" that the earth is warming. Though that's down from 77 percent in 2006, the margin is still large. Democrats are stronger believers than Republicans but mainly because tea party support is low.
It's useful for environmental groups to have global warming "deniers" (and, of course, behind them the sinister oil companies) as foils. The subliminal message is that once the views of these Neanderthals are swept away, we can adopt sensible policies to "do something" about global warming.
The reality is otherwise. The central truth for public policy is: We have no solution.
From 2010 to 2040, the U.S. Energy Information Administration projects global emissions will increase almost 50 percent. About 80 percent of global energy comes from fossil fuels (coal, oil, natural gas), which are also the major sources of carbon dioxide (CO2) emissions. At present, we have no practical replacement for this energy. No sane government will sacrifice its economy today -- by dramatically curtailing fossil fuel use -- for the uncertain benefits of less global warming sometime in the foggy future. (The focus of the U.S. global warming report on the present seems aimed at bridging this gap.)
Worse, almost all the projected increases in global emissions come from poorer countries, half from China alone. By contrast, U.S. emissions (and those of most rich nations) are projected to stay stable over the three decades. Economic growth is slowing; energy efficiency is increasing; and, in Japan and some European countries, populations are declining. Because poor countries understandably won't abandon their efforts to relieve poverty, any further U.S. emissions cuts would probably be offset by gains in China and elsewhere. This dims their political and environmental appeal.
The only real hope of disarming these conflicts is new technology. As yet, no magical fix has emerged. Though increasing, solar and wind power still represent a tiny share of global energy. "Carbon capture and storage" -- pumping CO2 emissions from power plants underground -- has been discussed for years. So far, it's not commercially viable.
Amid the rhetoric, there's enormous uncertainty about how much warming will occur, what changes (for good or ill) it will bring, and how easily (or not) we can adapt. My own oft-stated preference is for policies that might dampen global warming but would also address other problems. The most obvious idea is a carbon tax to help finance government and stimulate energy-saving technologies and new forms of non-carbon energy. If these technologies went global, the gap between rich and poor countries would narrow.
I do not claim this would be popular or that the desired technologies would materialize. But it's our best bet and would have the added virtue of being honest.