"At this late hour, there is only one way to peacefully prevent Iran from getting atomic bombs," said Israeli Prime Minister Benjamin Netanyahu in his remarks at the United Nations last September. "That's by placing a clear red line on Iran's nuclear program." Holding up a cartoon of a bomb -- the image looked like something Wile E. Coyote would buy from the Acme Corporation -- Netanyahu literally drew a red line just below the bomb's uppermost section, which was ominously labeled "final stage." Beyond that line, which could be reached as early as this spring, Netanyahu said, Iran would be more than 90 percent of the way to creating enough weapons-grade material for a bomb. "Faced with a clear red line," he argued, "Iran will back down."
There was a lot of talk in 2012 about a red line. During the US presidential election, for example, President Obama said that Iran should not be allowed to obtain a nuclear weapon. Mitt Romney vacillated on where the red line should be drawn but ultimately settled on a nuclear weapons capability. Like Netanyahu, neither Romney nor Obama was specific about what should happen if Iran crossed the red line, but a military threat was implied.
For existential threats, nothing beats a nuclear bomb with a short fuse. Even so, the handwringing over Iranian nukes seems disingenuous coming from world leaders who have had so little to say in recent months about another hot-button international issue: the looming catastrophe of global warming. Hurricane Sandy may have made climate change fashionable in New York City, but in Washington, legislators are still stuck on "it's the economy, stupid." Nuclear threats are taken seriously, but climate threats are largely ignored -- except, ironically, by military and intelligence agencies. The armed forces are taking steps to green their energy use, and the intelligence community is warning -- most recently in a report from the National Research Council, released 10 days late because of Hurricane Sandy -- that it is prudent to expect that climate events during the next decade will have "global security implications serious enough to compel international response" and that such consequences "will become more common further in the future." Meanwhile, the very people most inclined to believe that Iran nearly has the bomb -- despite a dearth of proof -- seem most disinclined to accept the scientific evidence calling for a red line on climate change.
When Netanyahu draws a red line, it's a line in the sand. But a red line for climate change is more like the line on your car's tachometer, which denotes the maximum speed at which your engine can safely operate. Rev the engine too high for too long, and you will overheat it to the point where it is ruined. Just like our planet.
The final stage. For your car, the red line is probably somewhere around 6,000 revolutions per minute. For climate change, it's 2 degrees Celsius. Warming beyond that level is widely acknowledged as "dangerous" anthropogenic interference likely to cause problems including extreme weather events, coastal inundation, decreased food production, and loss of biodiversity. The opening paragraph of the 2009 Copenhagen Accord, for example, recognizes "the scientific view that the increase in global temperature [beyond preindustrial levels] should be below two degrees Celsius."
Humans have already raised the planet's temperature by almost 0.8 degrees Celsius, and the results have been worse than scientists anticipated. Even if humans stopped adding carbon dioxide to the atmosphere tomorrow, atmospheric models estimate that the gases we have already emitted will raise global temperature by another 0.8 degrees Celsius. If the "final stage" comes when we have covered 90 percent of the distance to 2 degrees, we are almost there now.
Why red lines don't work. The problem with the Copenhagen Accord -- and the talks that have taken place since then -- is that it hasn't resulted in actions that will keep Earth's engine below its red line. Instead of easing our foot off the throttle, humans are burning more fossil fuels than ever.
A study published last year in the Proceedings of the National Academy of Sciences provides experimental evidence that focusing on a specific goal -- say, 2 degrees -- can, paradoxically, lead to inaction. As long as there is any uncertainty, however slight, about where the threshold of danger lies -- or about the consequences for crossing that threshold -- self-interest encourages countries to keep on emitting even though collectively they are better off reducing their emissions.
The carrot and the stick. If line-drawing isn't particularly effective, what's the alternative? Here we can look to Obama's dual strategy on Iran: Squeeze Iran with tough economic sanctions while simultaneously extending an invitation to negotiate on specific actions to be taken. This two-pronged approach could work for climate, too: Squeeze carbon emitters with a carbon tax while simultaneously creating incentives for concrete progress on energy conservation and efficiency -- measurable by audits and inspections.
If we must draw a red line, it should be in an oil field, because only by leaving most of the planet's remaining fossil fuels underground can we hope to prevent dangerous warming. Netanyahu drew his red line on Iran's nuclear-enrichment program, "because these enrichment facilities are the only nuclear installations that we can definitely see and credibly target." We can't see greenhouse gases, and we can't see temperature, but we can see and target the atmosphere's carbon-enrichment facilities: power plants and drilling rigs and gas-guzzlers.
Targeting is what should have happened at the climate conference in Doha last year. More than three years have already passed since governments agreed that emissions must be reduced to keep global temperature increases below 2 degrees. Now the focus of the international response to climate change must shift from goals and pledges to sanctions and inspections. Setting the red line at 2 degrees does not work unless the game is changed so that the players become collaborators rather than competitors, and the consequences of failure are guaranteed. We cannot afford to let another year go by without significant action; 2013 must be the year that we shift gears, learn how to use the brakes, and save our planet from being damaged beyond repair.