A team of international scientists heads to Chile’s station Bernardo O’Higgins in Antarctica on Jan. 22, 2015. (Natacha Pisarenko/Associated Press)

Debate moderators in the 2016 presidential election cycle have had plenty of data to pose strong questions to candidates regarding climate change. Impacts include mass dislocation, alterations in the spread of infectious diseases, more intense Western wildfires and record-breaking warmth in both 2014 and 2015. Almost a year before the first debate, the Pentagon issued a study identifying climate change as a national-security problem. “Destruction and devastation from hurricanes can sow the seeds for instability. Droughts and crop failures can leave millions of people without any lifeline, and trigger waves of mass migration,” said then-Defense Secretary Chuck Hagel.

Surely the Pentagon’s warnings could well have informed a number of sizzling questions from the leading lights of broadcast journalism regarding climate change.

No such luck. Twenty debates into the schedule — 15 on the GOP side (including the undercard events) and five on the Democratic side — the questions on this most pressing of modern issues show how easily journalists get sidetracked by frivolities in their quest to hold politicians accountable. The result is a lot of talk, dozens of hours of programming and little substance on a do-or-die matter of public policy. Perhaps PBS can patch up the shortcomings Thursday night at 9 Eastern, when it hosts the Democratic contenders from the University of Wisconsin at Milwaukee.

For tips on how to phrase a simple and consequential question, the PBS-ers may want to follow the example of an outsider. During the Oct. 13 CNN Democratic debate, Arizona State University graduate student Anna Bettis of Tempe, Ariz., asked via video, “As a young person, I’m very concerned about climate change and how it will affect my future. As a presidential candidate, what will you do to address climate change?” An extensive discussion of the topic followed.

Easily done, right?

Not right, to judge from other attempts by full-time journalists to poke at this topic. Here’s Bret Baier of Fox News at the Jan. 28 Republican debate: “Senator Rubio, on the issue of climate change, in 2008, you wanted Florida to get ahead of other states and establish a cap-and-trade system, a program for carbon emissions, which many Republicans thought at the time would hurt the Florida economy. Now, you’re a skeptic of climate change science. And in fact, you warn that federal efforts to fight climate change will cost U.S. jobs and hurt the U.S. economy. So why the change?” Surprise: That question failed to yield an extended discussion of climate change.

At the very first undercard debate, hosted by Fox News on Aug. 6 in Cleveland, host Bill Hemmer tried a similar formulation: “Senator Lindsey Graham, you worked with Democrats and President Obama when it came to climate change, something you know is extremely unpopular with conservative Republicans. How can they trust you based on that record?” That sentiment caught on at the Oct. 28 CNBC debate, at which Carl Quintanilla asked Graham: “You have said you believe that climate change is real. You said you accept tax increases as part of a budget deal with Democrats. You’ve co-sponsored a Senate immigration bill, providing a path to citizenship for those in the country illegally. Are you in the wrong party’s debate?”

To Graham’s credit, he gave a substantive answer: “No, I think I’m trying to solve problems that somebody better solve. Now, you don’t have to believe that climate change is real. I have been to the Antarctic; I’ve been to Alaska. I’m not a scientist, and I’ve got the grades to prove it. But I’ve talked to the climatologists of the world, and 90 percent of them are telling me that greenhouse gas effect is real. That we’re heating up the planet. I just want a solution that would be good for the economy that doesn’t destroy it.”

Also subpar was the question from CBS News’s John Dickerson to Sen. Bernie Sanders in the Nov. 14 Democratic debate: “Senator Sanders, you said you want to rid the planet of ISIS. In the previous date, you said the greatest threat to national security was climate change. Do you still believe that?”

As the inventory below reflects, there have been some reasonable questions about climate change. At the Sept. 16 debate, for instance, CNN’s Jake Tapper wondered about an essay by former secretary of state George P. Shultz titled “A Reagan Approach to Climate Change.” Fox Business’s Maria Bartiromo, too, asked about the trade-offs between a domestic energy boom and a climate change program. Not bad. Hey, at least those debates included questions on climate change. According to a study by the Winston Group, several contests included nothing at all on the energy/environment topic area. Whatever the case, there’s something to be said for a simple question — what will you do about X? — as opposed to the often tortuous inquiries that the network brain trusts spend untold hours thinking up.

Climate Change questions at 2016 debates (as indexed by a study of the Winston Group)

Aug. 6 Fox News GOP debate:

Bill Hemmer to Lindsey Graham: Senator Lindsey Graham, you worked with Democrats and President Obama when it came to climate change, something you know is extremely unpopular with conservative Republicans. How can they trust you based on that record?

Sept. 16 CNN GOP debate:

Jake Tapper to Marco Rubio: Ronald Reagan urged skeptics in industry to come up with a plan. He said, do it as an insurance policy in case the scientists are right. The scientists were right; Reagan and his approach worked. Secretary Shultz asks, why not take out an insurance policy and approach climate change the Reagan way?

Jake Tapper to Chris Christie: What do you make of skeptics of climate change such as Senator Rubio?

*Oct. 13 CNN Democratic debate:*

Voter to Martin O’Malley: As a young person, I’m very concerned about climate change and how it will affect my future. As a presidential candidate, what will you do to address climate change?

Anderson Cooper to Bernie Sanders: Senator Sanders, are you tougher on climate change than Secretary Clinton? . . . Secretary Clinton, I want you to be able to respond.

Oct. 28 CNBC GOP debate:

Carl Quintanilla to Lindsey Graham: You have said you believe that climate change is real. You said you accept tax increases as part of a budget deal with Democrats. You’ve co-sponsored a Senate immigration bill, providing a path to citizenship for those in the country illegally. Are you in the wrong party’s debate?

John Harwood: Governor Pataki, you’ve indicated you believe climate change is real and caused at least in part by human activity. So in 60 seconds, tell us what the federal government is to do about it.

Moderator: Governor Christie, you’ve said something that many in your party do not believe, which is that climate change is undeniable, that human activity contributes to it, and you said, quote: “The question is, what do we do to deal with it?” So what do we do?

Nov. 10 Fox Business GOP debate:

Maria Bartiromo: Senator Paul, you were one of 15 republicans to vote for an amendment which states that human activity contributed to climate change. President Obama has announced an aggressive plan to cut carbon emissions. At the same time, energy production in America has boomed. Is it possible to continue this boom, and move toward energy self-sufficiency, while at the same time pursuing a meaningful climate change program?

Nov. 14 CBS Democratic debate:

John Dickerson to Bernie Sanders: Senator Sanders, you said you want to rid the planet of ISIS. In the previous date, you said the greatest threat to national security was climate change. Do you still believe that?

Jan. 17 NBC News Democratic debate:

Lester Holt to Bernie Sanders: Senator Sanders, Americans love their SUVs, which spiked in sales last year as gas prices plummeted. How do you convince Americans that the problem of climate change is so urgent that they need to change their behavior?

Jan. 28 Fox News GOP debate:

Bret Baier: Senator Rubio, on the issue of climate change, in 2008, you wanted Florida to get ahead of other states and establish a cap-and-trade system, a program for carbon emissions, which many Republicans thought at the time would hurt the Florida economy. Now, you’re a skeptic of climate change science. And in fact, you warn that federal efforts to fight climate change will cost U.S. jobs and hurt the U.S. economy. So why the change?

Feb. 4 MSNBC Democratic debate:

Chuck Todd to Bernie Sanders and Hillary Clinton: President Obama got a lot of ambitious stuff done in his first year and a half. You’re going to have to make choices. And there’s a lot of heavy lifts. And he made choices. He did health care and it came at the expense, arguably, of immigration reform. Had he put immigration reform first, perhaps that gets done and health care doesn’t. So there are three big lifts that you’ve talked about: immigration, gun reform and climate change. What do you do first? . . . All right, but Senator Sanders . . . you’ve still got to do something first.