Scientist Tobias Friedrich says Earth could heat up 6 degrees C., almost 11 degrees F, in a single lifetime. Richard Heede finds 83 companies, plus 7 countries, are responsible for 65% of all greenhouse gases. He names names. Then restoring carbon to the soil, with Murielle Trouillet from the Government of France.
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REPORTING A PLANETARY FIRE
There is so much going on, as climate change unfolds world-wide. As a climate reporter, I feel like a town with two fire trucks and ten fires. Until just this week, North America has been unseasonably warm, as though winter might not come. Now it has, but it’s late. We had a bear in our front yard when they should have been asleep.
In another sign of the times, King Tides on top of higher seas invaded streets of American coastal towns.
But the biggest story is in the Arctic. Last week it was 36 degrees above normal, occasionally rising above the freezing mark, in the polar darkness. The sea ice coverage has never been lower at this time of year. Unusual storms broke it up even further. Nobody knows what this will mean, for sea ice next year, for changes in the Jet Stream and weather further south, for the future of the planet.
The cold that should have been at the pole slipped down into central and eastern Siberia. Schools closed down, when daytime highs were minus 30 degrees Fahrenheit. Almost 200 record lows were set in the region. The weather system has become twisted out of shape. We’ll have more on the developing Arctic emergency next week with our guest scientist Paul Beckwith.
According to NASA, 9 out of the last 12 months from October 2015 to September 2016 were above the 1.5 degree C mark, which is 2.7 degrees Fahrenheit warmer as a global average. We’ve already passed the safety line the Paris climate agreement hoped to avoid by 2100. And that doesn’t count the added warming power hidden by air pollution.
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TOBIAS FRIEDRICH – HOTTER FASTER
Despite foot-dragging and threats of obstruction from the arriving government of Donald Trump, the vast majority of countries recognize that climate change is a huge threat to the human project. Their plans for a response are based on models that project a fairly predictable ramp of warming, according to the amount of greenhouse gases in the atmosphere. It’s all under control, and nobody talks about the possibility of a genuine climate catastrophe this century.
But what if that neat carbon logic is wrong? Could we have underestimated both the severity and the pace of climate change? New science has emerged. A headline in the UK’s Independent newspaper November 9th reads: “Climate change may be escalating so fast it could be ‘game over’, scientists warn”. The sub-head says, quote, “New research suggests the Earth’s climate could be more sensitive to greenhouse gases than thought, raising the specter of an ‘apocalyptic side of bad’ temperature rise of more than 7C within a lifetime.”
The Independent’s Environment Correspondent Ian Johnston is writing about a new study also published November 9, 2016 in the journal Science Advances. The subject is difficult, the paper isn’t easy, and this interview may not be easy. But with stakes this high, I think you want to know.
I’ve reached the lead author Dr. Tobias Friedrich. He’s a Postdoc, researcher and lecturer at the International Pacific Research Center. That’s part of the University of Hawaii in Honolulu.
A CLIMATE OFF-THE-CHARTS HOT!
If we do not manage to reduce emissions substantially, or capture carbon back from the atmosphere, the IPCC says Earth could warm anywhere between 2.6 degree C., considered very dangerous, up to 4.8 degrees C, – that’s about 8.5 degrees Fahrenheit, and off-the-charts dangerous. That is pathway 8.5. Friedrich explains that pathway, and how his team calculated temperature changes over the most recent 800,000 years, as glaciers and hot periods came and went.
We’ve been talking about the paper “Nonlinear climate sensitivity and its implications for future greenhouse warming”. It’s newly published in the journal “Science Advances”. The paper is available to the public as a free full text.
For me, essential point is simple: warming does not follow a simple ramp. When it begins from a very cold point, it can warm slowly. When it starts from a relatively hot time, like the current interglacial period we live in, the Earth can warm much faster. The pace of global warming is relative.
I would add that the rate of warming would be simpler to measure if we lived on a dead planet. The physics of oceans, sun, and land are fairly well known, although the oceans still require a lot of study. The ice-world, the cryosphere, is much more fluid. A lot is unknown there. It seems like a new study on Greenland or Antarctica comes out every week.
For example, I just learned from a science alert service that a new study shows the Pine Island Glacier began an accelerated warming around 1940. That Antarctic glacier is the largest single glacial source of rising seas on the planet.
But now we have to add the plant systems, from gigantic plankton pools in the sea, to all the forests and grasses on land. Plus the frozen plant life in the permafrost. Once these natural climate regulators are accelerated or reduced, the whole climate can be altered. Perhaps a wild swing (or two) awaits us.
In any event, Tobias Friedrich tells us their calculations reinforce the findings of the Intergovernmental Panel on Climate Change (the IPCC). That surprises me, since global leadership just meeting in Marrakech Morocco, seem oblivious to the risk of a mega-shift possible this century. Surely we would talk and act on nothing else if we knew?
The British author Mark Lynas wrote a book called “Six Degrees, Our Future on a Hotter Planet“. But he concluded there was little future for humans in a world six degrees warmer. And he was using science at least ten years old. We’ve found out much more since then, including this research. We are talking about a wrenching change, something beyond human experience or imagination.
If you only listen to one Radio Ecoshock interview for the rest of this year, listen to this one! You can listen now…
 
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I expect reverberations from this paper for some time to come. There may be a long delay before the general public understands what’s in it – even though the results are cause for immediate alarm and action.
RICHARD HEEDE – LESS THAN A HUNDRED MADE MORE THAN HALF THE POLLUTION OF THE ATMOSPHERE!
We’ve heard of the 1%. But the number of corporations and countries who produced 65% of the greenhouse gases in the atmosphere is far smaller. According to our next guest, just 90 CEO’s and state leaders are responsible for the majority of pollution which is wrecking the climate known throughout civilization. They could, Richard Heede says, fit on two Greyhound buses. He names names, at least corporate names.
I find Richard Heede hard to describe. He’s a consultant with his own company called “Climate Mitigation Services“. Richard has a long list of studies and reports he’s published for cities and towns mostly in the Western United States. He’s written short helpful guides for consumers to understand their carbon footprint. He’s a one-man carbon tracker with a warehouse mind able to reconstruct the carbon footprint of the global industrial world, piece by piece. I reached Richard in Snowmass Colorado.
You can listen to this 23 minute interview with Richard Heede right now.
 
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We’re talking about Heede’s 2014 work “Tracing anthropogenic carbon dioxide and methane emissions to fossil fuel and cement producers, 1854–2010“, as published in the journal “Climatic Change”.
This report from Heede comes as a dose of reality in a world which has just turned darker, when it comes to climate change action. It’s a bit shocking, because the press always talks about national responsibility. We hear what each country emits, and we are all guilty. But now we draw back the curtain, and find only a few corporate actors.
Of course there are the usual suspects, namely the largest oil, gas and coal companies. Heede, supported by student researchers, went back decades (in some cases over a century) through company production records and other sources, to add it all up. Exxon/Mobil and the other “seven sisters” companies from the break up of Standard Oil top the list. That includes Chevron, Texaco and all that.
Historically, the Rockefeller family made the greatest profits from Exxon, and from Standard Oil before that. What about going beyond corporate accountability. What can we say about accountability of persons? That isn’t in Heede’s report. Maybe it’s work for future scholars, or maybe no one will ever be held responsible.
Then we have Royal Dutch Shell (Netherlands and UK), Total (France) and Saudi Aramco. America’s Peabody Coal is the largest coal source, but there are others, including China. China and 6 other countries had to be listed as countries rather than corporations, because there are no reliable records for corporations from those countries. Coal, Heede says, is responsible for 39% of all greenhouse gases in the atmosphere. As Trump would say, it’s huuuge. (As Trump doesn’t say, coal needs to stop.)
Heede also reveal this shocking fact: “Half of all the CO2 emissions in the industrial sector from fossil fuel and cement use have come since 1988.”
Of course, as the “developing world” developed, using fossil fuels, we had even more stuffed into the atmosphere since the year 2000. That really matters, because there is at least a ten year time delay before those greenhouse gases fully manifest as global warming. When it comes to the impact we’ve already made, it’s yet to come!
AN EARLY CARBON COUNTING PIONEER
Richard Heede has been studying this subject for much longer than most people. His online biography lists the title of his 1984 thesis: “A World Geography of Recoverable Carbon Resources in the Context of Possible Climate Change.” That lines up almost exactly with his report published in January 2014 in the journal “Climatic Change”. Heede was one of the very early pioneers of carbon in what we now know is the era of climate change.
Heede has also written consumer guide books. One example is “Carbon in Our Daily Lives: an exploration of everyday greenhouse gas emissions sources.” His bio says Rick “designed and built a passive-solar rammed-earth home at 2,300m in the central Rocky Mountains of Colorado. It saves two-thirds of the energy and four-fifths of the carbon emissions of typical homes in this climate zone.”
MY OPINION
It’s true that millions of people profited directly from fossil fuel companies. That includes employees, and investors, like pension funds. We all profited from the energy slaves made available to us in just a couple of generations. But some people definitely made more than others. There really are a small number of billionaires from fossil fuels, including the two wealthiest Americans as a pair, the Koch Brothers. Will anyone take this study further, making it more personal to come out and say WHO contributed most to the destruction of the climate?
It’s not polite to talk about the people who profited most from loading up the atmosphere. But I believe, even in dark times of Trumpian denial, this personal accounting will happen. After many climate disasters, people will ask: Who led us here? Who gained from planetary suffering? It’s not beyond possibility that a severely damaged society will ask for that wealth back, to be used for disaster repairs and relocation costs. What do you think?
Now that we know the small number of major conduits of human greenhouse gases to the sky, does that give us some hope that if we could assemble them into a small action group, to save the planet with a rational end-of-business plan?
THERE’S SNOW BUSINESS LIKE SNOW BUSINESS…
Richard has also written reports by and about Aspen Colorado. He is a passionate skier. Near the beginning of Radio Ecoshock, in December 2006, I played an interview by Betsy Rosenberg with Auden Shambler of Aspen. Then I interviewed Arthur Dejong of Whistler/Blackcomb, Canada’s best ski resort. Both resorts were really early in the game to realize global warming was a threat to their business. I asked in my show title, “Will Global Warming End Show Sports?” People are still skiing. I ask Richard for his prognosis.
Find another good article about this study here, from the Bulletin of Atomic Scientists.
SOIL FOR CLIMATE AND FOOD SECURITY: MURIELLE TROUILLET
Carbon dioxide in the atmosphere has crossed another dangerous threshold, going above 400 parts per million for the first time since humans appeared on Earth. To avoid a punishing climate shift, experts are searching for a large-scale way to capture carbon from the atmosphere and store it. Instead of the industrial solution advanced by some, the government of France proposes to capture CO2 with better agricultural and land management. It’s called the “4 per thousand” program. We’ll find out why, and how it works.
Our guest is the Project Manager for the 4 percent initiative and sustainable, for the Ministry of Agriculture, Agrifood and Forestry in the Government of France. Murielle Trouillet has been the Ministry lead for the 4 per thousand carbon-to-soil program, and other climate affairs. She is a graduate of AgroParisTech.
You can listen to this 12 minute interview with Murielle now.
Or download it in CD Quality (only).
The French Government are way out in the lead in this program to put more carbon into the soil. For example, in March of 2015, the French Minister of Agriculture was at a meeting in Montpellier, about “climate-smart agriculture“. As far as I can see, no other national government is so advanced in changing agriculture to benefit the climate.
But as Murielle tells us, it’s not just about climate change. There is a whole element of this program devoted to “food security“. All of us should pay attention to that, and demand it from our own governments. The official name of the program is: “4‰ Initiative : soils for food security and climate”
The English version of a French government web site says, quote:
“A ‘4‰’ [4 parts per thousand] annual growth rate of the soil carbon stock would make it possible to stop the present increase in atmospheric CO2.”
I’m not sure whether 4 in a thousand aims at leveling off our current emissions, or can it go farther to actually reduce CO2 in the atmosphere?
For those who keep track of the international agenda, and the role of the global south, this French project appeared in the hand-over of the Presidency of the COP climate talks, from Peru to France. I am speaking of the “Lima-Paris Action Agenda”. We briefly discuss that. You can find a full description of that agenda here.
Of course, any proposal draws it’s critics. Perhaps “climate-smart” agriculture is not the same as “agroecology”. Specifically, they worry that agricultural multinationals will use our climate fears as a business opportunity. Perhaps they will push super-fertilizers, herbicide tolerant crops as “green” climate-friendly products. Murielle tells us there is protection against that, as companies are not allowed to be a direct part of this government program. No lobbyists need apply, I suppose.
Read this in-depth article by Sara Velander and Jenna Farineau for an in-depth criticism of the possible perils of the 4 per thousand plan. It includes some juicy stuff on corporations pushing “green” fertilizers (with links to Norway and Wal mart) – plus a lot of stuff you need to know.
A key question, often overlooked by environmentalists, is the cost, and who is going to pay? Murielle talks to us about the economics behind a successful implementation of “4 per thousand”.
I think you may find these soil/carbon facts from the French government web site useful:
“Key figures
24 % of global soils are degraded at various levels, including 50 % of agricultural soils [source: Bai et al., 2013]
1 500 billion tonnes of carbon are stocked in soil organic matter, which is twice more carbon than atmospheric CO2 [source : IPCC, 2013]
1,2 billion tonnes of carbon could be stocked every year in agricultural soils which represents an annual rate of 4‰ compared to the surface soil horizon [source : IPCC, 2014]
Every years crop production in Africa, Asia and South America could increase by millions, by increasing 24/40 soil organic matter by 1 tonne/ha [Lal , 2006]
1,2 billion USD is the economic loss in crop production due to soil degradation [FAO, 2006]”
You can find out more about the use of soil as a weapon against climate change in this Yale 360 article “Soil as Carbon Storehouse: New Weapon in Climate Fight?“.
I would like to thank Karl Thidemann and Seth Itzkan of the non-profit Soil4Climate for suggesting this topic. Find that web site here, or on Facebook here, and Instagram here.
ANOTHER FULL WEEK
That’s another big week for Radio Ecoshock. Stay tuned for our next program where I’ll talk with climate scientist Paul Beckwith about the Arctic emergency. Plus you’ll hear a leading scientist in the field of carbon capture and storage – as he answers critic Kevin Anderson.
I couldn’t do this without the kind support of listeners. Some make one-time donations, others give me a ten-dollar-a-month paycheck. It’s listener-supported radio, as I go after key scientists, authors and activists to get close to the truth. If you can help, find out how on this page.
Don’t be afraid to write me with your story ideas, and things you think we should all know about. There’s a contact page on the Radio Ecoshock web site. Your comments go straight to my email in-box and I read every one.
Thanks for listening!
Alex
Radio Ecoshock
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Alex, before I start, I’d like to point out I’m a massive fan of yours, I’ve been listening for nigh on 10 years, I once made a paltry contribution and we once emailed. Just a thought: here you are talking with Richard Heede about the potential loss of skiing resorts in North America while a few 1000 miles south of you, in Bolivia, the country’s main glaciers and lakes are vanishing and millions face water shortages that are life-threatening right now. (https://robertscribbler.com/2016/11/23/climate-change-has-left-bolivia-crippled-by-drought/)
Wouldn’t it be possible for you to broaden the net somewhat and interview experts in these countries so that listeners could begin to appreciate what it feels like to live on the raw frontlines of climate change?
Totally true William! The situation in Bolivia is dire. About 20% of the water for two major cities, including the capital, comes from glaciers that are literally disappearing. This is another case of being one fireman with 200 fires reported! I just can’t get to them all as fast as they develop.
Keep in mind, my conversation with Richard about skiing was just an aside, from the main point that we talked about: who is responsible for the carbon in the atmosphere.
Hello Alex!
I don’t really have a comment on this week’s podcast, but I wanted to call something else to your attention, since you sometimes report on cli-fi: I think the public is finally ready for the genre to go mainstream with the new sci-fi TV series “Incorporated”, which officially starts airing on November 30th (in the US, though since it’s a Canadian-produced show like most sci-fi TV series these days, it should be airing where you can watch it about the same time). The plot of the show is mainly about massive social inequality and runaway, literally cut-throat capitalism (in the tradition of movies like “Gattaca” or “Brazil”), but the writers make it very clear that it all happens in a world dealing with serious repercussions of climate change. Even just in the pilot episode there are mentions of billions in damages from a hurricane; eco-terrorists from drowned island nations; New York already being similarly lost; heavily altered growing conditions for agriculture; frequent brown-outs and food shortages in the vast slums (there’s a slum drug lord shown eating a self-grown tomato as carefully as if it was expensive truffles, and even the rich can afford real meat only for special occasions); Canada building a wall to keep out millions of illegal immigrants from the US; and oil drilling in the ice-free Arctic. They didn’t say where in the US the story is supposed to take place, but they made the effort to light the daytime scenes in the tree-less slums with glaring sunlight like when US shows want to make clear a scene is taking place in Arizona or Mexico or some hot place like that, while the suburban gated community for corporate employees still has the kind of lush, evergreen vegetation you’d expect in a show filmed in Vancouver and supposedly set in the Pacific Northwest. Moreover, the show even mentions in the opening scroll that most governments have been driven into financial ruin by the burden of climate disasters, and the corporations that took over power in their place are fighting wars about “diminishing resources” – peak oil is going mainstream too?
Very few sci-fi TV shows up till now even just included climate change in their predictions for what life will be like for future generations – in fact, the only one I can think of was the quickly cancelled “Minority Report” series last year, and even that only mentioned it in small ways that didn’t really affect the lives of the characters, since at its core it was a fairly optimistic cop show, not a dystopian story. And while dystopian sci-fi in which American society is collapsing and the characters have to deal with much harder lives is quite popular these days (which is quite telling, in so far as that many people can feel that something is going very wrong, or maybe yearn for a more direct, survivalist lifestyle on some level), the reason for the collapse is almost always conveniently unrealistic, like an alien invasion (“Colony”, “Defiance”) or a zombie apocalypse (“The Walking Dead”, “Van Helsing”) or a literal act of God starting the biblical End Times (“Aftermath”, “Dominion”). In the rare case that the apocalypse isn’t totally impossible in the real world, it’s caused by some single cataclysmic event that humanity doesn’t have control over and thus isn’t responsible for, like a unnaturally lethal pandemic started by a few evil people (“12 Monkeys”), or an asteroid impact (like the one just revealed to have been the start of all the shortages and wars that eventually led to the complete ecological collapse in the future that the characters on “Travelers” are trying to alter). Or it’s some sort of alternative history designed to warn against some particular brand of politics (usually fascism in a way that isn’t significantly altered from what arose in Europe in the 1930s, and usually arising in the fictional setting without any realistic macro-social reasons – i.e. not as a backlash against masses of climate refugees or to suppress civil dissent against resource wars – thus making it look safely unlikely as possible development for American future, too) – there’s an online TV version of “The Handmaid’s Tale” planned for next year, for example. The closest we’ve gotten to a man-made ecological apocalypse in mainstream TV sci-fi is in the backstory of the show “Wayward Pines”, with humanity but not other mammals being wiped out by some very vaguely defined environmental problems (but the Earth is conveniently pristine and healthy again after just 2000 years, with the eponymous evergreen trees still populating the same place as before, so the problem can’t have been nuclear fallout or runaway climate change) and some humans somehow “evolving” in that short time into exclusively carnivore, non-tool-using naked apes that make Neanderthals look like geniuses, in response to the environmental pressures. Because that’s totally how evolution works, and because apex predators relying on a large supply of herbivore prey animals don’t die out first if there are environmental problems, and because intelligence would not be a survival advantage, apparently. Any environmental message that show might have intended was undermined by the world-building being written by someone who must have flunked high school science class, as well as by the overwhelming stupidity of the plan to save some original humans (e.g. abducting random people, putting them in cryogenic sleep, and then after waking giving them all a comfortable middle-class small-town lifestyle where almost no-one actually grows food or does any other basic productive work, instead getting assigned ‘essential’ jobs like beautician or ice cream salesman; also, barely pubescent 13-year-olds are pressured to have sex and get pregnant to “populate the Earth”, but all the adult women who could much more safely give birth appear to have been put on permanent birth control…) and the ridiculous failure of these well-armed and -supplied people to protect their walled enclave against what’s basically just packs of upright-walking, slow wolves with tiny claws and no sense of self-preservation. Since the suspense of disbelief breaks badly in the face of such nonsense, this story effectively is no better than just another zombie apocalypse fantasy.
In contrast, “Incorporated” is the first time I’ve seen in mainstream sci-fi where the overall awfulness of the situation is just the result of ‘business as usual’ – and it’s not even set safely far away in the future to insulate it from the viewer’s reality (it’s set some 60 years from now). And it’s all presented perfectly seriously and as a scarily likely scenario, as long as you accept the premise that climate change and resource depletion are real – it’s not written as some kind of half-comedic, hyperbolic satire or made into a modern fairytale by the inclusion of fantastic elements (like humanoid aliens or time travel) and physically impossible or far-out sci-fi tech tropes. There isn’t even any A.I. so far, just self-driving electric cars, very convincing nature holograms, and an instant skin-healing spray used in plastic surgery.
– continued –
– continued –
‘Evil mega-corporations control everything’ type sci-fi has generally gained popularity over the last few years, possibly because the now middle-aged, established TV writers grew up with 1980s cyberpunk, but these shows (“Dark Matter”, “Killjoys”, “The Expanse”, etc.) these days are normally set long after humanity started colonizing Space. Amazingly, “Incorporated” seems to admit that we might not make it that far, due to basically the reasons stated in “Limits to Growth”. Considering how demonized and silenced that whole concept was for so long, I find it encouraging that some TV producers finally seem to think that it wouldn’t stretch the ‘suspension of disbelief’ too far – at least for the kind of young-ish audience that watches sci-fi series on TV. We’ll see if the advertisers are okay with the message too, or if it will be quickly yanked from the air.
Anyway, maybe this new anti-capitalist cli-fi show is just a cynical cash-in on the whole Sanders ‘socialism light’ movement. But they wouldn’t really have had to put so much emphasis on the Earth being ravaged by climate change for that. And I’ve heard some time ago that there’s a TV adaptation planned of Margaret Atwood’s “MaddAddam” trilogy, which also deals with rampant corporate power, and some ecological themes, though the immediate reason for the death of most of humanity is still bio-terrorism. So maybe it does mean the zeitgeist has changed enough so that the corporate masters of our entertainment feel they can’t totally deny the effects and true reasons of environmental degradation anymore if the stories they let artists tell the masses about our future are to remain meaningful and not ridiculously out-of-touch with reality.
PS: I do have a comment to the podcast after all: The part about the CO2-emissions due to chemical reactions in the production of cement is somewhat misleading. It’s true that the making of ‘cement’ – as in, the special concrete that hardens even under water and is used for house fundaments and hydro dams and such – does release a lot of CO2 in the process of turning calcium carbonate into other calcium compounds (silicates, aluminates, etc.) that will then react with water to produce complex, hard calcium hydrates. But basic masonry mortar and the stuff used to pour ‘concrete’ floors use a different chemical reaction, in which the calcium carbonate is turned into quicklime – calcium oxide – and releases CO2, but that same amount of CO2 has to be reabsorbed by the wet mortar as it dries and hardens, otherwise it wouldn’t glue anything together. In the end, you effectively have calcium carbonate stone again. That’s why masonry houses have to be “dry lived” at first – the process needs CO2 from living beings and warmth. It takes years to complete, though, so it is true that, much like felling a tree for burning and then replanting, you do have to deal with a sudden spike in CO2 that only very slowly gets reduced again. And of course, the process heat necessary for the quicklime burning does come from fossil fuels, so the industry is a large net-emitter, just like steel-forging or glass-making. Interestingly, both these processes need calcium oxide as well, so it’s not just produced for building houses.
And I think Mr. Friedrich misunderstood your question about “icehouse / greenhouse Earth” and ended up confusing you. As I learned it, there are long phases in which year-round ice exists on the planet (“icehouse” or more commonly “ice age”), and there are much warmer phases when water in solid form doesn’t much feature on the planet, because it just doesn’t get cold enough anywhere (“greenhouse”). The latter have historically been more common, as your interviewee last week (or the one before?) said. But the entire evolutionary development of mankind (and other large mammals) and the ecosystems we depend upon has happened under “icehouse” conditions, which is why scientists think we probably can’t survive in a climate as was when the dinosaurs where still around. Now, during such an “ice age”, which can last millions of years, there are long periods with lots of ice (“glacial period” – i.e. what non-scientists generally mean by the word “ice age”) and shorter periods in which the ice only covers the poles and highest mountain ranges (“interglacial period”). The latter generally only last ten thousand years or so on average, and the entirety of human civilization has happened in this current, unusually climatically stable interglacial period. That’s why humans existed in physically modern form for over a hundred thousand years as nomadic hunter-gatherers before developing agriculture and starting to settle down – agriculture just wasn’t possible before because the weather wasn’t predictable for long enough stretches of time, e.g. when the rainy season would come or when frost would reliably be over. (And this didn’t happen everywhere at the same time, by the way. It wasn’t possible to grow grains in Scandinavia until the “Medieval Optimum” started in the 11th century, which is why until then they needed to constantly export their overpopulation in the form of Viking raids and the earlier spread of Germanic tribes across Europe during and after the Roman Empire.) There is a theory that we were actually scheduled for another glacial period about the time we got the “Little Ice Age”, but then the industrial revolution happened and emitted enough CO2 to undo that trend. The problem is that by now we’ve put so much of the CO2 that had been removed by non-rotting trees in the carboniferous era (plants had just evolved lignin to make wood and grow tall, but fungi took a few million years to catch up and evolve a way to digest the new carbohydrate source, so a lot of the wood just sank into the mud until there wasn’t enough oxygen around it anymore to digest it, and then it slowly got compressed into coal) back into the atmosphere that we’ve catapulted the system out of the “icehouse” stage entirely and we’re set to get back the “greenhouse” climate of the carboniferous era. But “greenhouse earth” and “interglacial period” does not mean the same thing, the way he accidentally made it sound.