The money quote on climate change in the first Democratic presidential “debate” was Senator Bernie Sanders’s response to moderator Anderson Cooper’s question, “what is the greatest national security threat to the United States?”

“The scientific community is telling us,” Sanders said, “that if we do not address the global crisis of climate change, transform our energy system away from fossil fuel to sustainable energy, the planet that we’re going to be leaving our kids and our grandchildren may well not be habitable” [emphasis added].

Well, no, Senator, “the scientific community” is not telling us that. A few scientists—very few—may be saying something similar (though one would be hard pressed to find it in scholarly publications as opposed to comments to the news media or speeches at rallies), but most aren’t saying anything remotely like it, especially those last five words. The earth has been through much warmer periods, and during them life of all sorts, plant and animal, thrived. From 1990 to 2013, the IPCC, using computer climate models, posited climate sensitivity (warming effect of added CO2 after feedbacks) in the range of 2–4.5˚C with a best estimate of 3˚, and in 2013 it reduced the lower bound to 1.5˚ and abandoned any “best estimate.” Even the upper end of that range would come nowhere near making the earth uninhabitable.

But lately, empirical studies of climate sensitivity (as opposed to the computer models, which have predicted on average twice the warming observed; 95% of which predict more warming than observed, implying that the errors aren’t random but driven by bias; and none of which predicted the absence of warming for the last 18 years and 8 month) point to its being far less than what the IPCC has long claimed. (See our review of such studies here, and Judith Curry’s ongoing tracking of them here.)

Earlier in the debate Sanders claimed, “the scientific community is virtually unanimous: climate change is real, it is caused by human activity, and we have a moral responsibility to transform our energy system away from fossil fuel to energy efficiency and sustainable energy and leave this planet a habitable planet for our children and our grandchildren.”

Again, no, Senator. The claims (repeated by President Obama and others ad nauseam) of 97% scientific consensus are bogus. There is perhaps agreement among a little over half of climate scientists that the earth has warmed around 0.8˚ C since 1850 and that human activity has contributed significantly to that warming since about 1950, but even that consensus doesn’t extend to assertions that human activity is the main or sole cause, or that we have a moral responsibility to fight it, let alone to fight it by transforming our energy system, let alone that our failure to do so could leave the earth uninhabitable, let alone that climate change is the greatest national security threat facing the United States.

We can perhaps forgive the candidates for appealing passionately to consensus on climate change. They’re politicians. Want to know who won an election? Count votes. Consensus matters in politics.

But consensus doesn’t matter in science, particularly not when it’s not spontaneous but artificially manufactured through a process of propaganda and intimidation. Want to know how much CO2 warms the earth? Don’t count votes—study the data.

Most troubling was the utter failure of any of the candidates to consider the benefits of added CO2 to plant growth, greening the earth and making food more abundant for everyone, people and animals alike, or the impact on the world’s poor of the demand to transform our energy economy from abundant, affordable, reliable fossil fuels (which now provide over 85% of all the energy consumed) to diffuse, expensive, unreliable-because-intermittent wind and solar. The consequence, as the petition Forget ‘Climate Change’, Energy Empowers the Poor points out, would be to slow, stop, or reverse economic growth, trapping billions in abject poverty and the high rates of disease and premature death invariably associated with it.

Now, from the New York Times transcript of last night’s Democratic presidential debate, here’s all that the candidates said about climate change, in their own words, in sequence:

Chafee: “a real threat to our planet”

O’Malley: “the great challenge of climate change”

Sanders: “Today, the scientific community is virtually unanimous: climate change is real, it is caused by human activity, and we have a moral responsibility to transform our energy system away from fossil fuel to energy efficiency and sustainable energy and leave this planet a habitable planet for our children and our grandchildren.”

Clinton: “… we’re going to create more good-paying jobs: by investing in infrastructure and clean energy, by making it possible once again to invest in science and research, and taking the opportunity posed by climate change to grow our economy.”

O’Malley: “… nuclear Iran remains the biggest threat, along with the threat of ISIL; climate change, of course, makes cascading threats even more (inaudible).”

Sanders (responding to Anderson Cooper’s question, “what is the greatest national security threat to the United States?”): “The scientific community is telling us that if we do not address the global crisis of climate change, transform our energy system away from fossil fuel to sustainable energy, the planet that we’re going to be leaving our kids and our grandchildren may well not be habitable.”

Clinton: “I have been on the forefront of dealing with climate change, starting in 2009, when President Obama and I crashed (ph) a meeting with the Chinese and got them to sign up to the first international agreement to combat climate change that they’d ever joined.”

O’Malley: “I have put forward a plan — and I’m the only candidate, I believe, in either party to do this — to move America forward to a 100 percent clean electric grid by 2050. We did not land a man on the moon with an all-of-the-above strategy. It was an intentional engineering challenge, and we solved it as a nation. And our nation must solve this one. So I put forward the plan that would extend the investor tax credits for solar and for wind. If you go across Iowa, you see that 30 percent of their energy now comes from wind. We’re here in Las Vegas, one of the most sustainable cities in America, doing important things in terms of green building, architecture and design. We can get there as a nation, but it’s going to require presidential leadership. And as president, I intend to sign as my very first order in office the — an order that moves us as a nation and dedicates our resources to solving this problem and moving us to a 100 percent clean electric grid by 2050.”

Webb: “… the question really is how are we going to solve energy problems here and in the global environment if you really want to address climate change? And when I was in the Senate, I was an all-of-the-above energy voter. We introduced legislation to bring in alternate energy as well as nuclear power. I’m a strong proponent of nuclear power. It is safe, it is clean. And really, we are not going to solve climate change simply with the laws here. We’ve done a good job in this country since 1970. If you look at China and India, they’re the greatest polluters in the world. Fifteen out of the 20 most polluted cities in the world are in one of those two countries. We need to solve this in a global way. It’s a global problem and I have been very strong on — on doing that. The — the agreements — the so-called agreements that we have had with China are illusory in terms of the immediate requirements of the — of the Chinese government itself. So let’s solve this problem in an international way, and then we really will have a — a way to address climate change.”

Sanders: “I believe — and Pope Francis made this point. This is a moral issue. The scientists are telling us that we need to move extremely boldly. I am proud that, along with Senator Barbara Boxer, a few years ago, we introduced the first piece of climate change legislation which called for a tax on carbon. And let me also tell you that nothing is gonna happen unless we are prepared to deal with campaign finance reform, because the fossil fuel industry is funding the Republican Party, which denies the reality of climate change … and certainly is not prepared to go forward aggressively. This is a moral issue. We have got to be extremely aggressive in working with China, India, Russia. … The planet — the future of the planet is at stake.”

Clinton: “When we met in Copenhagen in 2009 and, literally, President Obama and I were hunting for the Chinese, going throughout this huge convention center, because we knew we had to get them to agree to something. Because there will be no effective efforts against climate change unless China and India join with the rest of the world. They told us they’d left for the airport; we found out they were having a secret meeting. We marched up, we broke in, we said, “We’ve been looking all over for you. Let’s sit down and talk about what we need to do.” And we did come up with the first international agreement that China has signed. Thanks to President Obama’s leadership, it’s now gone much further. … And I do think that the bilateral agreement that President Obama made with the Chinese was significant. Now, it needs to go further, and there will be an international meeting at the end of this year, and we must get verifiable commitments to fight climate change from every country gathered there.”

Sanders: “The planet — the future of the planet is at stake.”

Chafee (in response to Anderson Cooper’s question “Which enemy are you most proud of?”): “I guess the coal lobby. I’ve worked hard for climate change and I want to work with the coal lobby. But in my time in the Senate, tried to bring them to the table so that we could address carbon dioxide. I’m proud to be at odds with the coal lobby.”

Chafee: “America has many challenges confronting us — ending the perpetual wars, addressing climate change ….”