The U.N. Intergovernmental Panel on Climate Change has just completed a series of landmark reports that chronicle an update to the current state of consensus science on climate change. In a sentence, here’s what they found: On our current path, climate change could pose an irreversible, existential risk to civilization as we know it – but we can still fix it if we decide to work together.

But in addition to the call for cooperation, the reports also shared an alarming new trend: Climate change is already destabilizing nations and leading to wars.

That finding was highlighted in this week’s premiere of Showtime’s new star-studded climate change docu-drama Years of Living Dangerously. In the series’ first episode, New York Times columnist Thomas Friedman traveled to Syria to investigate how a long-running drought has contributed to that conflict. Climate change has also been discussed as a “threat multiplier” for recent conflicts in Darfur, Tunisia, Egypt, and future conflicts, too.

Climate change worsens the divide between haves and have-nots, hitting the poor the hardest. It can also drive up food prices and spawn megadisasters, creating refugees and taxing the resiliency of governments.

When a threat like that comes along, it’s impossible to ignore. Especially if your job is national security.

In a recent interview with the blog Responding to Climate Change, retired Army Brig. Gen. Chris King laid out the military’s thinking on climate change:

“This is like getting embroiled in a war that lasts 100 years. That’s the scariest thing for us,” he told RTCC. “There is no exit strategy that is available for many of the problems. You can see in military history, when they don’t have fixed durations, that’s when you’re most likely to not win.”

In a similar vein, last month, retired Navy Rear Adm. David Titley co-wrote an op-ed for Fox News:

The parallels between the political decisions regarding climate change we have made and the decisions that led Europe to World War One are striking – and sobering. The decisions made in 1914 reflected political policies pursued for short-term gains and benefits, coupled with institutional hubris, and a failure to imagine and understand the risks or to learn from recent history.

In short, climate change could be the Archduke Franz Ferdinand of the 21st century.

Earlier this year, while at the American Meteorological Society annual meeting in Atlanta, I had a chance to sit down with Titley, who is also a meteorologist and now serves on the faculty at Penn State University. He’s also probably one of the most fascinating people I’ve ever spoken with. Check out his TEDxPentagon talk, in which he discusses how he went from “a pretty hard-core skeptic about climate change” to labeling it “one of the pre-eminent challenges of our century.” (This interview has been lightly edited and condensed.)

Q. You’ve been a leader when it comes to talking about climate change as a national security issue. What’s your take on the connection between war and climate?

A. Climate change did not cause the Arab Spring, but could it have been a contributing factor? I think that seems pretty reasonable. This was a food-importing region, with poor governance. And then the chain of events conspires to have really a bad outcome. You get a spike in food prices, and all of a sudden, nobody’s in control of events.

I see climate change as one of the driving forces in the 21st century. With modern technology and globalization, we are much more connected than ever before. The world’s warehouses are now container ships. Remember the Icelandic volcano with the unpronounceable name? Now, that’s not a climate change issue, but some of the people hit worst were flower growers in Kenya. In 24 hours, their entire business model disappeared. You can’t eat flowers.

Q. What’s the worst-case scenario, in your view?

A. There will be a discrete event or series of events that will change the calculus. I don’t know who, I don’t know how violent. To quote Niels Bohr: Predictions are tough, especially about the future. When it comes, that will be a black swan. The question is then, do we change?

Let me give you a few examples of how that might play out. You could imagine a scenario in which both Russia and China have prolonged droughts. China decides to exert rights on foreign contracts and gets assertive in Africa. If you start getting instability in large powers with nuclear weapons, that’s not a good day.

Here’s another one: We basically do nothing on emissions. Sea level keeps rising, three to six feet by the end of the century. Then, you get a series of super-typhoons into Shanghai and millions of people die. Does the population there lose faith in Chinese government? Does China start to fissure? I’d prefer to deal with a rising, dominant China any day.

Q. That sounds incredibly daunting. How could we head off a threat like that?

A. I like to think of climate action as a three-legged stool. There’s business saying, “This is a risk factor.” Coca-Cola needs to preserve its water rights, Boeing has their supply change management, Exxon has all but priced carbon in. They have influence in the Republican Party. There’s a growing divestment movement. The big question is, does it get into the California retirement fund, the New York retirement fund, those $100 billion funds that will move markets? Politicians also have responsibility to act if the public opinion changes. Flooding, storms, droughts are all getting people talking about climate change. I wonder if someday Atlanta will run out of water?

Think back to the Apollo program. President Kennedy motivated us to land a man on the moon. How that will play out exactly this time around, I don’t know. When we talk about climate, we need to do everything we can to set the stage before the actors come on. And they may only have one chance at success. We should keep thinking: How do we maximize that chance of success?

Climate change isn’t just an environmental issue; it’s a technology, water, food, energy, population issue. None of this happens in a vacuum.

Q. Despite all the data and debates, the public still isn’t taking that great of an interest in climate change. According to Gallup, the fraction of Americans worrying about climate “a great deal” is still roughly one-third, about the same level as in 1989. Do you think that could ever change?

A. A lot of people who doubt climate change got co-opted by a libertarian agenda that tried to convince the public the science was uncertain – you know, the Merchants of Doubt. Unfortunately, there’s a lot of people in high places who understand the science but don’t like where the policy leads them: too much government control.

Where are the free-market, conservative ideas? The science is settled. Instead, we should have a legitimate policy debate between the center-right and the center-left on what to do about climate change. If you’re a conservative – half of America – why would you take yourself out of the debate? C’mon, don’t be stupid. Conservative people want to conserve things. Preserving the climate should be high on that list.

Q. What could really change in the debate on climate?

A. We need to start prioritizing people, not polar bears. We’re probably less adaptable than them, anyway. The farther you are from the Beltway, the more you can have a conversation about climate no matter how people vote. I never try to politicize the issue.

Most people out there are just trying to keep their job and provide for their family. If climate change is now a once-in-a-mortgage problem, and if food prices start to spike, people will pay attention. Factoring in sea-level rise, storms like Hurricane Katrina and Sandy could become not once-in-100-year events, but once-in-a-mortgage events. I lost my house in Waveland, Miss., during Katrina. I’ve experienced what that’s like.

Q. How quickly could the debate shift? How can we get past the stalemate on climate change and start focusing on what to do about it?

A. People working on climate change should prepare for catastrophic success. I mean, look at how quickly the gay rights conversation changed in this country. Ten years ago, it was at best a fringe thing. Nowadays, it’s much, much more accepted. Is that possible with climate change? I don’t know, but 10 years ago, if you brought up the possibility we’d have gay marriages in dozens of states in 2014, a friend might have said “Are you on drugs?” When we get focused, we can do amazing things. Unfortunately, it’s usually at the last minute, usually under duress.

This article is part of Future Tense, a collaboration among Arizona State University, the New America Foundation, and Slate.

This story was produced by Slate as part of the Climate Desk collaboration.

A lot of carbon-rich waste is left behind after a cornfield is stripped of its juicy ears. It used to be that the stalks, leaves, and detrital cobs would be left on fields to prevent soil erosion and to allow the next crop to feast on the organic goodness of its late brethren. Increasingly, though, these leftovers are being sent to cellulosic ethanol biorefineries. Millions of gallons of biofuels are expected to be produced from such waste this year — a figure could rise to more than 10 billion gallons in 2022 to satisfy federal requirements.

But a new study suggests this approach may be worse for the climate, at least in the short term, than drilling for oil and burning the refined gasoline. The benefits of cellulosic biofuel made from corn waste improve over the longer term, but the study, published online Sunday in Nature Climate Change, suggests that the fuel could never hit the benchmark set in the 2007 U.S. Energy Independence and Security Act, which requires that cellulosic ethanol be 60 percent better for the climate than traditional gasoline.

The problem is that after corn residue is torn out and hauled away from a farm field, more carbon is lost from the soil. This problem is pervasive throughout the cornbelt, but it’s the most pronounced in Minnesota, Iowa, and Wisconsin, owing in part to the high carbon contents of soils there.

Researchers used a supercomputer to run models to estimate the effect of removing corn residue from 128 million acres of farmland in 12 corn-farming states. Removing the residue was found to release 50 to 80 grams of carbon dioxide from the exposed soil for every megajoule of biofuel produced. Add to that figure the biofuel’s tailpipe CO2 emissions and, voila, you get an average of 100 grams of CO2 released for every megajoule of power produced — which is 7 percent worse than emissions from regular old gasoline.

The key findings are shown in the following graph from the paper. The top line shows that soil organic carbon (SOC) is gradually lost over nine years when corn residue is left in place. But when the residue is hauled off to be turned into biofuel, as shown in the dashed lower line, the loss of soil carbon is more rapid. The loss of such soil carbon is a blow for the farm — crops need that material to grow. But it’s also a blow for the climate, because the carbon ends up in the atmosphere as a greenhouse gas.

The researchers found that the loss of soil carbon is an issue regardless of whether some of the residue is removed from a field or all of it. “If less residue is removed, there is less decrease in soil carbon, but it results in a smaller biofuel energy yield,” said report coauthor Adam Liska, an assistant professor at the University of Nebraska at Lincoln.

The research was funded with $500,000 from the federal government — which was quick to pan the results.

An EPA spokeswoman told the AP that the study “does not provide useful information relevant to the life cycle greenhouse gas emissions from corn stover ethanol.” And the biofuels industry complained that the researchers did not give a good explanation for why their conclusions contradicted other recent studies.

But the AP has previously exposed gaping holes in the EPA’s own studies, which have concluded that ethanol provides big climate benefits.

We asked Liska how officials could use his findings to help slow down global warming. He suggested that they start by using their ears (not the corn kind). “If emissions are going to be decreased, the EPA should accept these findings as valid,” he replied.