Former Florida Governor Jeb Bush (R) described the certainty of scientific knowledge on climate change as “convoluted” yesterday. Specifically, he said that it’s unclear “what percentage is man-made and what percentage is natural.”
He also claimed that people who say the science is “decided on” are “arrogant.” At the same time, he said “The climate is changing, and we need to adapt to that reality.”
He shared a very similar message in Iowa with the Daily Signal, which published a video of their interview with Bush earlier today. He added that he wants to forge “a consensus on a common sense approach” for dealing with climate change.
In April, Bush stuck a bit more to energy policy when speaking about climate change and also told an audience that “we need to work with the rest of the world to negotiate a way to reduce carbon emissions.”
So what does the science say on the specific point Gov. Bush raised? And what do we really want candidates for the country’s highest office to debate?
Uncertainty doesn’t mean a lack of urgency (on climate or anything else)
Scientific reports make it clear that burning coal and oil and destroying tropical forests is responsible for the majority of observed planetary warming over the past several decades. When we look at the scientific literature, 97 percent of relevant papers either explicitly or implicitly endorse the evidence that such activities are causing recent climate change.
Overall, scientists are as certain that industrial activities are causing climate change as they are that smoking causes lung disease.
More specifically, scientists have robust estimates of how much heat different types of emissions are trapping in our atmosphere. And if we dig a bit deeper, my colleague Brenda Ekwurzel explains, we see that much of the scientific uncertainty related to planetary warming rests on industrial emissions other than carbon dioxide, namely aerosols, short-lived sunlight-reflecting particles that are also released when we burn fossil fuels, as well as ocean cycles that create short-term climate variability, too.
But here’s the thing: heat-trapping carbon dioxide stays in the atmosphere for generations. So arguing about whether industrial emissions are responsible for 62.6%, 73.8% or 98.2% of warming so far isn’t a terribly productive exercise for policymakers.
When scientists look forward instead of backward, it’s clear that the percentage of warming that can be attributed to industrial activities will keep increasing if we burn more fossil fuels. Indeed, a world of greater certainty on this narrow question is also one in which we have already locked in more warming. What will we say then? That we finally have enough certainty to know it’s too late?
Bigger picture, any scientific topic can be picked apart publicly by focusing on the nitty-gritty details. There is no such thing as perfect knowledge in science. Nor, I’d argue, is there perfect knowledge in foreign policy, public health, economics, or any other topic with which a policymaker has to make decisions, but it’s much rarer to hear them use uncertainty in those fields to justify inaction.
The bottom line is this: scientists know enough to be able to identify concrete climate risks. We should expect policymakers to figure out how to respond to them, not second-guess the science.
Arrogance versus anti-science is not a productive debate
It’s no secret the public attitudes toward climate science are politicized. Most Democrats accept basic climate science while about half of Republican and Republican-leaning citizens feel the same way.
But in the realm of national politics, the debate has often devolved into some Democrats admonishing Republicans for being anti-science and some Republicans claiming that Democrats are trying to bully them on the science. That is probably the source of Gov. Bush’s gripe about “arrogance” in the climate debate. Interestingly, Bush cautioned against this dynamic two years ago, when he told the Conservative Political Action Conference that Republicans shouldn’t hazard being perceived as “anti-science.”
I can’t think of any scientist who wants politicians to argue about their work, whether it’s Ebola, vaccines, evolution, or climate change. They’d much prefer politicians to view their research as one of many policymaking tools instead of yet another partisan cudgel.
University of New Hampshire climate researcher Cameron Wake put it well in a recent interview about potential presidential candidates weighing in on his field of expertise. He said we need to differentiate between the science – which lays out significant risks for society – and policy, which we can make based on ideology, values, economics, public and private interests, politics, or other factors. Indeed, it would be arrogant to assume that any one policymaker, party, or interest group has a monopoly on what the correct policies are to deal with climate change.
The good news is that there are, in fact, many diverse ideological approaches for dealing with climate change, including among conservatives:
- Libertarian Jerry Taylor has pointed out that things like sea level rise threaten property rights and could therefore justify government policies designed to reduce emissions and deal with climate damage.
- Groups like the R Street Institute are working on integrating climate science into federal flood insurance reform to prevent future costly taxpayer bailouts.
- Former Rep. Bob Inglis (R-S.C.) and the group RepublicEn are promoting a suite of policies, including ending energy subsidies and instituting a carbon tax swap to reduce payroll and corporate taxes.
Forging a consensus on climate should involve these ideas, too. They are worthy of debate on a national stage.
Debating risks and policy instead of reality
Bush noted that we need to adapt to the reality of a changing climate. Local leaders in Florida would probably agree. They have already come together to help one another prepare for rising seas. It’s also worth noting that there is some uncertainty when it comes to how fast the seas will rise; this has not prevented Floridians from making reasonable determinations about what degree of sea-level rise they want to prepare for.
It would be great to know what role aspiring national leaders think the federal government has in supporting such local efforts.
I hope the candidates will talk more about their vision for dealing with the climate risks we face. And I hope voters and journalists will ask them questions that focus the debate on how to respond. That’s the debate we need – not another round of politicized arguments over established scientific facts.