Nine climate tipping points now ‘active,’ warn scientists

No, I don’t see a “climate communication”  blitz in the run up to the latest UN Climate Change Conference or anything like….that.~cr

University of Exeter

More than half of the climate tipping points identified a decade ago are now “active”, a group of leading scientists have warned.

This threatens the loss of the Amazon rainforest and the great ice sheets of Antarctica and Greenland, which are currently undergoing measurable and unprecedented changes much earlier than expected.

This “cascade” of changes sparked by global warming could threaten the existence of human civilisations.

Evidence is mounting that these events are more likely and more interconnected than was previously thought, leading to a possible domino effect.

In an article in the journal Nature, the scientists call for urgent action to reduce greenhouse gas emissions to prevent key tipping points, warning of a worst-case scenario of a “hothouse”, less habitable planet.

“A decade ago we identified a suite of potential tipping points in the Earth system, now we see evidence that over half of them have been activated,” said lead author Professor Tim Lenton, director of the Global Systems Institute at the University of Exeter.

“The growing threat of rapid, irreversible changes means it is no longer responsible to wait and see. The situation is urgent and we need an emergency response.”

Co-author Johan Rockström, director of the Potsdam Institute for Climate Impact Research, said: “It is not only human pressures on Earth that continue rising to unprecedented levels.

“It is also that as science advances, we must admit that we have underestimated the risks of unleashing irreversible changes, where the planet self-amplifies global warming.

“This is what we now start seeing, already at 1°C global warming.

“Scientifically, this provides strong evidence for declaring a state of planetary emergency, to unleash world action that accelerates the path towards a world that can continue evolving on a stable planet.”

In the commentary, the authors propose a formal way to calculate a planetary emergency as risk multiplied by urgency.

Tipping point risks are now much higher than earlier estimates, while urgency relates to how fast it takes to act to reduce risk.

Exiting the fossil fuel economy is unlikely before 2050, but with temperature already at 1.1°C above pre-industrial temperature, it is likely Earth will cross the 1.5°C guardrail by 2040. The authors conclude this alone defines an emergency.

Nine active tipping points:

  1. Arctic sea ice
  2. Greenland ice sheet
  3. Boreal forests
  4. Permafrost
  5. Atlantic Meridional Overturning Circulation
  6. Amazon rainforest
  7. Warm-water corals
  8. West Antarctic Ice Sheet
  9. Parts of East Antarctica

The collapse of major ice sheets on Greenland, West Antarctica and part of East Antarctica would commit the world to around 10 metres of irreversible sea-level rise.

Reducing emissions could slow this process, allowing more time for low-lying populations to move.

The rainforests, permafrost and boreal forests are examples of biosphere tipping points that if crossed result in the release of additional greenhouse gases amplifying warming.

Despite most countries having signed the Paris Agreement, pledging to keep global warming well below 2°C, current national emissions pledges – even if they are met – would lead to 3°C of warming.

Although future tipping points and the interplay between them is difficult to predict, the scientists argue: “If damaging tipping cascades can occur and a global tipping cannot be ruled out, then this is an existential threat to civilization.

“No amount of economic cost-benefit analysis is going to help us. We need to change our approach to the climate problem.”

Professor Lenton added: “We might already have crossed the threshold for a cascade of inter-related tipping points.

“However, the rate at which they progress, and therefore the risk they pose, can be reduced by cutting our emissions.”

Though global temperatures have fluctuated over millions of years, the authors say humans are now “forcing the system”, with atmospheric carbon dioxide concentration and global temperature increasing at rates that are an order of magnitude higher than at the end of the last ice age.


The latest UN Climate Change Conference will take place in Madrid from December 2-13.

The article is entitled: “Climate tipping points – too risky to bet against.”

From EurekAlert!

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Al Miller
November 27, 2019 9:20 pm

So let’s recap: A trace gas necessary for all life on earth that every single mammal on earth exhales continuously and is at historic lows is now responsible for the “end of the world”!? Yeah I think I’ll just get up and drive my SUV to work tomorrow while the great wanna be messiahs of junk science pound the pulpit, and those funding them continue to pray for the masses to just believe.

Bill Powers
Reply to  Al Miller
November 28, 2019 10:50 am

Enjoy your SUV while you can All. They are not giving up on this. They are in for a penny/in for a pound.
They are going to use this to strip you of you individual liberties. If you live in the U.S, they are going to use this as the requisite planet menace to override the bill of rights and once they are done, they are going to tax and regulate you into your government appointed orwellian duties under the collective. Your only hope is to slide into the grave before they have established total control.

Reply to  Bill Powers
November 28, 2019 11:33 am

In the US the real hope is a Trump re-election and 3 or 4 more originalist Supreme Court justices followed by court cases greatly weakening the central government and returning the US to a republican form of government that follows the constitution as written, leaving citizens the true ability to vote with their feet by moving to states that no longer provide welfare, Medicaid, etc. etc. to able bodied individuals. (Stopped for a breath) Those states would experience the rising tide lifting all boats, even more than the “Red” states of the currently now enjoy.

Let the “Blue” states support all the leeches to society without a federal government subsidy. Their bankruptcy is guaranteed and when they run out of money, the leeches will be squeezed into being somehow productive, beginning a resurgence in the greatness of the good old U S of A.

BTW: The liberal media who decided the RED and BLUE obviously got it backwards, and the original (NBC) map had it the other way. BLUE be for True Blue American Patriots, i.e. conservative states. RED be for the liberal leaning and in some cases now (California anyone) communist one party states. Knowing liberals I would think the MSM did it just for that purpose, so that the above phrases could not be used. See the following link for a short discussion of the Red/Blue thing and people moving as mentioned above.

John Endicott
Reply to  Drake
November 29, 2019 9:18 am

BTW: The liberal media who decided the RED and BLUE obviously got it backwards, and the original (NBC) map had it the other way. BLUE be for True Blue American Patriots, i.e. conservative states. RED be for the liberal leaning and in some cases now (California anyone) communist one party states

Except NBC wasn’t the only news organization with color maps, nor even the first, and each organization had a different color scheme. For example, in the 1908 election (roughly 70 years before NBC’s maps), The New York Times printed a special color map, using blue for Democrats and yellow for Republicans, to detail Theodore Roosevelt’s 1904 electoral victory, that same year That same year, the Washington Post published a color supplement that used red for Republican-leaning states, blue for Democratic-leaning states, yellow for “doubtful” states and green for territories, which had no presidential vote. In 1976, when NBC was using Blue for republicans and Red for Democrats, ABC was using yellow for Republicans and blue for Democrats.

The simple fact is there was no consistent color scheme until after the 2000 election, and that basically emerged from the new analysis in the days following that contentious election with NBC’s Tim Russert (of Meet the Press fame) coining the term “red state/Blue state” as he discussed the election results based on NBCs color scheme that year (which had happen to be red for Republicans and Blue for Democrats, had NBC chosen blue and white that year, then when Tim coined blue state/white state that likely would have become the standard)

November 27, 2019 9:26 pm

There is certainly a tipping point in the number of people flying to UN Climate Change Conferences and other similarly useless climate junkets.

Reply to  nicholas tesdorf
November 28, 2019 1:15 pm

If they are not sailing/walking or, possibly, horse riding – they obviously don’t believe a syllable of the nonsense [aka True Gospel of the 1%ers].
Greta does – poor soul.
I do hope she hasn’t been irretrievably damaged by her brain-washers.


November 27, 2019 10:15 pm

The sad thing is, I actually think they believe their own sensationalised rhetoric. ‘Tipping Point’ is just the latest information operation, propaganda-based, ‘buzz phrase’ designed by the ‘group thinkers’ to instil fear and panic about a trace gas (0.0410% of our atmosphere) critical to all life on planet earth.

This is scary and getting scarier…it’s easy to see how religious cults form and propagate so easily, or how despotic regimes headed by dictatorial zealots are able to take control of entire populations. I think we’re screwed.

Bill Powers
Reply to  Fred
November 28, 2019 12:02 pm

Buzz phrase equals the newest Hobgobln. “They” consist of two groups: “Fools” and “Tools”.

The Puppetmasters are pure evil. They don’t just want, they need to control the masses. They have the wealth to acquire the best government money can buy and they have sent forth Tools to brainwash the Fools. Michael Man is a Tool as is ALGORE. Some Tools are simply unwitting Fools such as “Bill Nye the Science Guy.” He is the equivalent of the “Mr. Green Jeans” of the Climate movement. Greta Thunberg is the poster child of the Fools.

The Puppetmaster know they don’t have to fool all the people, just a voting majority of them. And Yes Fred, I think you are right. Given the level of stupid the Millennial class of fools have lowered to, thanks in large part to our public school system and a highly engaged Higher Education System with its “sell out” group of Tools, we are Screwed with a capital S.

Rod Evans
November 27, 2019 11:04 pm

Warning to all virgins living within walking distance of a volcano. Get out of there fast, before the crazies from the climate emergency cult, determined to appease the earth gods, come round.
Sanity has reached a tipping point….

Reply to  Rod Evans
November 28, 2019 6:52 am

I think it’s very important to remember that these “activists” are a micro-minority of the Western population, mostly feeding at the UN trough, and the only reason they’re able to make a big noise is the sensationalist media gives them a bullhorn.

The average person, whether they “believe” we’re affecting the climate or not, does not see a “crisis” in play, and mostly ignores all this raving chatter. AGW is a known ratings-killer and regular people (as opposed to weather nerds) do not frequent AGW agit-prop websites. They have no control and don’t care. Anyone who HAS done 15 minutes of research knows the truth and is now red-pilled on this issue.
Indoctrinated youth grow out of these hysterias as the world moves on–you know anyone losing sleep over the Ozone Hole or Acid Rain lately?

Most of the people who go around harping on this are unhappy angst-ridden unfulfilled upper-middlers who know their cubicle-lives are meaningless, so they’re searching for meaning through “Save the Planet” tm do-gooding, trying for cred in a “fashionable cause” to be let in the “upper crust” club. That’s about it.

Ill Tempered Klavier
Reply to  Goldrider
November 28, 2019 12:45 pm

Save the planet ?!?!?!? The planet doesn’t need saving. Some people are (beep), but the planet’s doin’ just fine.

George Carlin

November 27, 2019 11:15 pm

“Despite most countries having signed the Paris Agreement, pledging to keep global warming well below 2°C, current national emissions pledges – even if they are met – would lead to 3°C of warming.”

For the umpteenth time, everyone who signed up at Paris COP21 knew that their pledges at that conference wouldn’t achieve the 2°C target. Those pledges (the Nationally Determined Contributions) were modelled (yes I know, modelled) to achieve 3.5°C to 3.7°C (Climate Interactive and MIT modelling respectively). The Paris Agreement baked in a ratcheting process of increasing NDC promises in later years, at 5-yearly meetings. We’re only now at the stage of the first expected ratcheting up.

Whether we do ratchet up or whether we should/shouldn’t is a separate issue from pointing out this perennial problem of mis-citing the aims of the Paris Agreement, namely, that they all agreed to 2°C in 2015 but our NDC pledges don’t reflect that commitment yet. EVERYONE at Paris 2015 and at Madrid 2019 knows this. The point of the Paris Agreement 2°C was to set in train the ratcheting up process at 5-yearly intervals.

Eurekalert are making it sound like the Paris NDC commitments were supposed to deliver 2°C and that we’re breaching those commitments by overshooting them by huge amounts. The reality is that some countries will overshoot them by a few percent but that pales in significance compared with the massive hikes in commitments ‘needed’ for a 2°C world (e.g. 40% reduction for EU in 2030 rising to an 80-100% reduction in 2050). That eye-watering extra 40-60% reduction needed isn’t a breach of the EU’s Paris NDC commitments, it’s the extra percentage reduction that was known to be needed back in 2015 and that was expected to be promised incrementally in the 5-yearly “ratcheting up” of commitments.

This comment isn’t about whether these commitments are needed or not, nor about the validity of global warming. It’s about the correct representation of the terms of the Paris Agreement regarding emission commitments. Misrepresentation of where we are on those commitments is what is contributing to the scaremongering all around us. And the misrepresentation is perpetrated on both sides of the debate: by the alarmists including the MSM/Eurekalert and by the sceptics who say “look, the Paris Agreement is falling apart because their commitments aren’t achieving their agreed 2°C target”.

Everyone needs to grow up and start representing the Paris Agreement and the NDC commitments/ratcheting honestly. Only then can the alarmists have any shred of a case and only then will sceptics be able to argue against the case for increasing commitments from a solid understanding of where we are already on that journey.

Reply to  Scute
November 28, 2019 8:45 am

What climate sensitivity are all these “pledges” based on?

Ken Irwin
November 27, 2019 11:18 pm

I understand the scientific ignorance of journalists in general – it was never part of their curriculae.

But I don’t understand their ignorance of words that they use.

My favorite being “unprecedented” which they habitually use with reckless abandon whenever they write about climate change.

A quick fact check will demonstrate that almost any such “unprecedented” value has occurred before.

I have seen reporters say things like “this is unprecedented – we last saw temperatures like this in the 30’s” or some such oxymoronic disambiguation.

Perhaps I have been too generous – maybe they really are simply ignorant on all counts and the profession simply attracts BA dropouts.

mike macray
Reply to  Ken Irwin
November 28, 2019 2:12 am

Ken Irwin,
….”I understand the scientific ignorance of journalists in general – it was never part of their curriculae.”
Besides low level literacy requirements, the upgrade to science journalism is a three week course in genuflection at the altar of climate catastrophy in the Temple of Doom..

Reply to  Ken Irwin
November 28, 2019 6:54 am

Why let facts get in the way of a good story? People want sensational scary stories. Facts are boring and don’t sell newspapers and freak people into maxxing their credit cards. 😉

November 27, 2019 11:25 pm


November 27, 2019 11:31 pm

And to say that water vapor varies between 20.000 and 40.000 ppm in the atmosphere. The Current increase of co2 is the same equivalent as an increase Of 20-30 ppm of water vapor. So i wonder what would happen if worldwide water vapor would increase by 1000 ppm. Or decrease by the same amount….. a runaway greenhouse effect? /sarc

tom Connor
November 27, 2019 11:45 pm

Tipping points are some sort of limited time offer fallacy: Crying wolf creates artificial deadlines intended to instill fear & urgency: We only have nn years until something bad happens. Past examples include the Population bomb, Y2K & the Mayan Calendar fiasco. But it never happens and the goalpost moves. Hasn’t the IPCC moved away from such rhetoric?

November 27, 2019 11:51 pm

If all the hand-wringing climate zealots really cared about saving the planet from human activity, they would simply kill themselves for the greater good.

Patrick MJD
November 28, 2019 12:17 am

If you go back to the early 20th century there is evidence 1 and 2 happened before, and recovered, and were reported on, with CO2 much lower then than today. So the constant cries about CO2 CAUSING these tipping points are totally wrong.

Matthew Sykes
November 28, 2019 12:32 am

What a load of crap. As the Amazon has ben deforested they have found hundreds and hundreds of old towns and villages. It is clear the amazon once supported a population of millions and was large;y farm land a few centuries ago. It is NOT a tipping point.

Neither is Arctic ice. The albedo change is not that great, at low angles of incidence, as found in the arctic, water is quite reflective, but also during low sea ice months, ie summer, it is quite cloudy there. Also ice acts as an insulating layer. It keeps the water warmer.

Forest growth is on the increase, as we know. and on and on, just a load of BS with zero science and load of lies behind it.

Paul of Alexandria
Reply to  Matthew Sykes
November 28, 2019 7:11 am

An interesting book is “The Lost City of the Monkey God: A True Story” by Douglas Preston
“In 2012, author Douglas Preston joined a team of explorers searching for Ciudad Blanca (“The White City”), a legendary ruin hidden in the dense jungle of eastern Honduras. To this point the city – also known as “the Lost City of the Monkey God” – was literally a legend; while various hucksters and hoaxers had claimed to have discovered the abandoned metropolis, no credible evidence had ever been presented, and its very existence remained shrouded in doubt.”

They found the city, in the middle of what is now jungle, and it was quite clear that it had once been the center of a thriving civilization, and not in a jungle. The civilization died out, and the city was abandoned, following the devastating plagues inadvertently introduced by the Spaniards circa 1500, and the jungle reclaimed its territory.

November 28, 2019 12:44 am

Whilst not subscribing to the CO2 is evil meme, I do think we do need to take more care of the environment, although not in a stewardship kind of way, that smacks too much of anthropocentrism to me.

I think we can all agree, there is nothing wrong with recycling glass, textiles or anything else that can be economically recycled for example.

Cutting down on our energy use makes a lot of sense to me simply because it saves me money.

Collectively, we are destroying vast swathes of rain forest in the name of palm oil, overfishing the seas and meat farming to unsustainable levels. I think we need to recognise this. I also think we need to recognise without the huge meat farms, food would be a lot more expensive than it is.

Reducing the amount of meat we eat may help, but who of us is prepared to give up a nice piece of steak? Not me, that’s for sure. I’m not a vegetarian by any means, but I do like meat-free meals a couple of times in the week. Not for any eco-mentalist reason, just because they taste nice.

Perhaps if we stopped having so many cats and dogs as pets, not working animals, we could cut down on feeding them meat. I’m OK with that.

Reply to  Redge
November 28, 2019 1:52 am


A woman who lives local to me said I was bad because I drive a car, she had recently been to a XR meeting regarding the new silver town tunnel in london (its needed) But a few weeks after, she started says that the greens are idiots and need to be stopped, I was curious and asked for details, she said “they want us to stop keeping pets” and as a dog foster lady she saves many dogs from certain death, but because she had to give up the things she loves, she is now firmly against xr and any other green Crackheads…. Imagine if the tens of millions of people in england were told that they can’t drive, have pets, or go on lovely cheap holidays to europe and beyond 😐

Reply to  Sunny
November 28, 2019 3:14 am

I think if we were to take away all mobile phones from school kids, we could halt fun Fridays, I mean climate strike Fridays, dead in its tracks.

As an added bonus just think of how much evil CO2 emissions we’d save!

Reply to  Redge
November 29, 2019 6:22 am

Hey, taking phones away from school kids and/or millennials is like taking away their oxygen! Cruel and unusual punishment! 😉

Reply to  Redge
November 28, 2019 2:13 am


I read somewhere credible (and I should have kept it) that the people most likely to alter their lifestyles to embrace energy saving, land stewardship, diet change etc. are climate sceptics.

Simply because we inquire more into the subject of global warming than alarmist’s and are far more knowledgeable.

Reply to  HotScot
November 28, 2019 3:23 am

I remember this too and can’t find it.

To be honest I think it’s more common sense than knowledge, although common sense seems to be rare with the warm-mongers.

Reply to  Redge
November 28, 2019 3:00 am

Better still eat the pets, kill two birds (and cats and dogs) with one stone

Rod Evans
Reply to  Redge
November 28, 2019 8:59 am

Forget using stones, wind turbine blades are far more effective and they can spin as long as there is wind, so killing two birds is just for starters….

John Endicott
Reply to  Redge
November 29, 2019 9:26 am

Redge: kill two birds…with one stone

Wind Turbines: Hold my beer….

November 28, 2019 1:23 am

Evidence is mounting? Is it, may I see it please…

Isn’t the below, a copy and paste from the normal rubbish that the u.n. or ipcc write??

East Antarctica would commit the world to around 10 metres of irreversible sea-level rise.

Reducing emissions could slow this process, allowing more time for low-lying populations to move.

edi malinaric
Reply to  Sunny
November 28, 2019 8:31 am

Hi All – good luck with melting East Antarctica = max temperature in December is MINUS 32C.

Cheers edi

Reply to  edi malinaric
November 29, 2019 5:49 pm

I estimate at the very moment 30/11/2019 that over an area of approximately 900,000 sq.miles the temperature in central and outlying areas of Antarctica is approx. -30oC . Mid winter over a similar area it is usually approx -45oC +. Antarctica is going to melt ! “I’d buy that for a dollar “.

November 28, 2019 1:46 am

When the tipping point thing gets old try the active and inactive tipping point thing and when the active and inactive tipping point thing gets old try something even scarier and keep the fear thing going with childish fear mongering activism disguised and sold as science.

November 28, 2019 2:03 am

Only nine.

November 28, 2019 5:04 am

“The latest UN Climate Change Conference will take place in Madrid from December 2-13.”

I haven’t heard anything lately about Greta. Is she still crossing the Atlantic somewhere? Is she going to make it to the conference in time to yell at them, too?

Reply to  BobM
November 28, 2019 7:36 am

Apparently Northwest of the Azores.

I’m pleased she and the crew look like they will make it across safely, although it’s likely they will land in Lisbon not Galicia

It’s taken 2 weeks so far, but it looks like she will make it to the boondoggle on time, especially as the president of Extremadura, the socialist Fernández Vara, has already put an electric car at her disposal.

Obviously, the electricity for the car comes from sustainable unicorn farts.

Tombstone Gabby
November 28, 2019 11:36 am

I don’t recall having seen it mentioned anywhere else. In “An Introduction to American Archaeology”, Vol. 1, – Gordon R Willey – page 12, “…was the hot dry “climatic optimum” or Altithermal of 5000 to 2500 B.C. at which time many regions now habitable were probably not so.”

Or do climatologists have a different name for that period?

November 28, 2019 12:34 pm

“There is a reasonable amount of science associated with the climate change issue, but all things considered, and give or take a religion or two, never has so much rubbish been espoused by so many people on so little evidence.”
Emeritus Professor Garth Paltridge.

November 29, 2019 3:55 am

“Nine climate tipping points now ‘active,’ warn scientists”

Now that is a considerable relief for me to read. It means it is now officially too late. So we can happily give up on all the bullshit and tell the green freaks to f….off.

Gordon Dressler
November 29, 2019 7:28 am

From the second paragraph in the University of Exeter article (press release?):
“. . . great ice sheets of Antarctica and Greenland, which are currently undergoing measurable and unprecedented changes much earlier than expected.”

Unprecedented, huh? Planet Earth has previously experienced FIVE “greenhouse (aka hothouse) Earth” periods, varying in durations from tens of millions of years to billions of years, during which there was no glacial ice and no polar ice caps on the planet. That’s a really tough precedent to exceed.

Upon this jaw-dropping moment, I found there was no need to read further into the article.

Gordon Dressler
November 29, 2019 7:40 am

Now, back to the real world . . . the “quiet” behavior of the Sun over the last several years indicates that Earth (via the Sun’s behavior) MAY have crossed a tipping point that brings on a long term period of global cooling, similar to the precedent of the Little Ice Age. If there is any “climate crisis” or “climate emergency” that is worthy of that name, this would be it.

Recent history shows that many more people across the globe die from cold than from heat. Also, food crops grow better in warm environments than in cool environments.

November 29, 2019 11:09 am

And that hodgepodge of unsupported political assertions is the “science” skeptics are said to deny.
I consider it eminently reasonable if not a matter of pride to deny these insipid assertions masquerading as science.

Johann Wundersamer
December 3, 2019 7:38 am


University of Exeter

More than half of the climate tipping points identified a decade ago are now “active”, a group of leading scientists have warned.

This threatens the loss of the Amazon rainforest and the great ice sheets of Antarctica and Greenland, which are currently undergoing measurable and unprecedented changes much earlier than expected.


Hard times for ~cr

when University of Exeter incl. a group of leading scientists

have warned bevor threatens of loss for Amazon rainforest and the great ice sheets of Antarctica and Greenland,

while ~cr is eager to 1st time real experience of loss for Amazon rainforest and the great ice sheets of Antarctica and Greenland.

Brian R Catt
December 3, 2019 10:55 am

Tipping point is an obvious nonsense while there are oceans. Current change is under the massive negative feedback to change in both directions, but increasingly strong as temperatures rise due to the way evaporation works, that also flatlines the 8 degree average climb from glacial to interglacial conditions in 7Ka. The oceans reduce SST by increased evaporation, and then increase albedo as more clouds form, which shuts down warming as insolation is reduced and also controls the upper limit of the range of the interglacial in the two stage bang bang oscillation that is the current 100Ka ice age control system. The level of feedback currently in force from these two effects is c.140W/m^2 per NASA. Adequate as a control of a few W/m^2.

There is no “Tipping Point”. It’s an obvious nonsense demonstrated by so many ice age interglacial events that all stopped when temperatures got where we are, for very powerful and obvious physical reasons that the oceans control, Younger Dryas or not. Look at the evidence and come up with another explanation.

PS I suggest that the particular 100Ka, and 41Ka before that, interglacial warming is driven entirely by the increased ocean heating by submarine volcanoes caused by the much greater effects of gravitational solid tide variations on the dailym of the Earth’s crust at this time, as also observed in the emissions record. Unaffected by Dryas like SST events, oceans keep rising as the volcanoes heat them, until the SST change is stopped by the increasingly massive negative feedback of evaporation and clouds, as well as T^4.

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