Climate Tipping Points in Oceans, Ice, Forests - Myles Allen

The impacts of climate change that probably worry people the most are irreversible changes that affect the entire world, such as a collapse of the west Antarctic ice sheet, shutdown of the global thermohaline circulation, loss of the Amazon biome, or a melting of Arctic permafrost.

Sudden, unpredictable and irreversible changes can happen in response to a gradual warming. What is known about these risks at 1.5°C, 2°C and higher levels of warming?

This lecture was recorded by Myles Allen on 5th March 2024 at Barnard's Inn Hall, London

Myles is the Frank Jackson Foundation Professor of the Environment.

He has contributed extensively to the Intergovernmental Panel on Climate Change (IPCC), including as Coordinating Lead Author for the 2018 IPCC Special Report on Global Warming of 1.5°C. He has published extensively on how human and natural influences on climate contribute to observed climate change and extreme weather risk, and the implications for adaptation and mitigation policy.

The transcript and downloadable versions of the lecture are available from the Gresham College website:

[fekixrudolfbischof]

Work as a farmer in Spain like me and you'll see what a tipping point is. It could be our last olive harvest if we don't get water from desalination which needs a lot of energy. On what dwarf planet do you live?

[martiansoon]

@58:30 Yea, likelihood of wars rises when natural resources like food and water dwindles.

Losing coral reefs means 1 billion people are our of job and food. That amount of people that are seeking something else will make many areas unstable.

Places where sea level rise wil hit are yet another. Already in Florida people are starting to see this and they are migrating away.

Mass migration from dried conditions in Africa and Central America has pushed people away. And have created multiple conflicts. And are rising hatred against refugees.

If things go wrong we may even accelerate our own doom by starting nuclear war over climate driven issues.

[lancechapman]

Unhelpful does not mean incorrect. We can still help, it is too late to stop!

[wowplayer]

Could we harvest the melt water? Build water pipelines to some of the major reservoirs? Would that reduce some of the sea Ievel rise and other issue's? Such as temperature, current and salinization levels? I know that it sounds like a nearly impossible feat with logistics and cost but I would say that our survival is priceless.

[sixvee]

“I accepted to come to this meeting to have a sober and mature conversation. I’m not in any way signing up to any discussion that is alarmist. There is no science out there, or no scenario out there, that says that the phase-out of fossil fuel is what’s going to achieve 1.5C.”
- Sultan Al Jaber, President of COP 28, also CEO of Abu Dhabi National Oil Company

Mukhtar Babayev will be the president for COP 29; he is also a former executive of the State Oil Company of Azerbaijian Republic.

Seems more and more likely, scenario SSP5-8.5 of the IPCC assessment may come to fruition (or at least the higher end of the spectrum). I say enjoy what you can, while you still can; pity the generations to come.

[stokepusher]

We have time to act, but not time to waste. Also I think we can mitigate the worsening of it in general, but 'fix it', is idealistic. We can make the best of a bad situation, by trying to do our best, but we can't return to a 'fix' of how it was before carbon. So let's make the best go of it, for what it's worth in regards of that, and not give out/give up

[louisjimenez]

It's Solar System change. The Sun is what drives the whole change.

[mawkernewek]

5:20 ah, those Grauniad yellow labels, warning the reader to check whether we are currently at war with Eurasia or Eastasia right now, and that the article may not follow the most up to date form of Newspeak.

[davidrussell]

The thing is, despite the claims, no one has ever shown how it could be physically possible for atmospheric CO2 to ever measurably influence temperatures near Earth's surface.

[thetombaxter]

As green house gases continue to accumulate, and the world warms, borel forests will increase burn rates and spread soot over the Arctic, and as the Arctic Ocean warms methyl hydrides, and other organics bound in permafrost will release more CO2, and CH4, and will lead to positive feed back.

[bipolarmarmalade]

I hate his word whiskers. I’m. Um. Um .

[j.s.c.]

Maybe Tony Blair was right and we did pass some tipping points already. The Antarctic sea ice has clearly entered a new state. Fire behavior and high temperatures are clearly in new states. I would not be so quick to dismiss Tony Blair’s prediction just because his deadline has passed.

[grahamgillard]

I listened for twenty minutes. He showed a graph where someone in the 70’s predicted large warming in the decades to come. I gave up. I’m tired of catastrophic predictions that never come true. The prediction from Tony Blair that he quotes is a perfect example of why we shouldn’t believe him. Yet he strangely tries to use Blair’s lies as support for his own argument. Weird.

[jamesgreig]

Having watched most of the video, hoping he would come up with some concrete data, I discovered that this entire presentation was simply demonstrating the futility of hypothetical conjecture with very little data to support his ideas.
Net result, the concept of tipping points appears like utter nonsense.
He's simply not factoring in that Mother Earth has her own protection mechanisms that, as has been displayed over millennia, rights wrongs very efficiently.
Just look at the last 25 years, extra co2, slightly warmer and Earth has decided to grow her green cover by close to 20%. That is, an area greater than the entire United States, of extra green space helping the equilibrium situation.
I have faith in our Earth more than theoretical scientists, but, we still need these scientists for our development of our knowledge.

[BROWNDIRTWARRIOR]

Interesting science but a painful delivery.

[huntera]

The circular reasoning offered by the speaker is insultingly shallow.

[scasey]

If you don’t believe in climate change, please relay your opinions to your children & grandchildren. They will hold you accountable in the decades ahead as the consequences for climate change become an unavoidable reality.

[Me-ckzh]

According to Greta's word in 2018, the tipping point should have been happening within five year after her comment. Prophets of doom!

[dancooper]

Excellent presentation! Wish I could be as optimistic as Myles.

[rvdb]

SEARCH FOR: "Semantic Scholar Glacier and lake-level variations in west-central Europe over the last 3500 years".
During Roman times there were virtually no glaciers in the Alps, while in 1859/60 they reached their maximum size of the past 3500 years thanks to the Little Ice Age.