David Attenborough: 'Climate Change 2007 predictions for 2020

If the clathrate bomb goes off Norway will likely be too hot

Hang on this is not the COVID thread

Thing is the old can discuss this in the clear knowledge that it will be little more than a nuisance to them whilst the young will live through the worst of it in their old age, things will be getting noticeably bad by the time I am over 80 but the world won't have ended it will just be more obvious that it is going to.

Yeah but it's a question of how quickly it affects the entire planet.

I've not watched the other video you posted yet.

Basically the reason why everyone has been calling for action to prevent or at least limit temperature increase to 1.5 degrees for years has been to avoid the methane danger in the permafrost and in the oceans, the outlook could be good or at least acceptable and sustainable if we managed to transform the world energy economy to renewables.

The problem is that it is an enormous mountain to climb and because a very large part of the population of the planet don't want to believe there is even a problem they actively refuse to be convinced that the cost or effort is worth it, why make clean electricity that costs a bit more just now when you can make cheaper dirty electricity the way they always have, never mind that it will run out one day that's someone else's problem way in the future.

They are worrying about a leak in their roof while their house burns down because they are completely blind to the fact that there is a fire, somehow they can't smell the smoke.

If the methane gets released in probably tens of gigaton quantities then it is all over, never mind that it breaks down fairly quickly that won't matter, things will likely go downhill pretty quickly if that event happens but it is still probably 50 years away from being bad enough that we can't stop it or at least prevent a runaway tipping point.

edit: I did a bit of checking and I am probably being over dramatic on the methane certainly on the oceanic methane as they think the thermal signal could take up to a thousand years to reach a lot of the deeper reserves but there is a lot of worry about shallower waters and the Siberian permafrost.

Some numbers still point at 6 degrees of warming in a period of as little as 80 years and that would render large parts of the planet unliveable.

edit 2: We should also remember that the opposite of what I was saying to Malcolm earlier could happen in that if the Gulf Stream collapses or moves south we in the UK could see dramatic swings from deep freezing winters and glaciers in Scotland to horrible summer heatwaves every year, it's not a guaranteed simple warmer climate for the UK and northern Europe.

The cows are a part of it, it is not just their methane but the land that gets cleared for grazing and the transport costs of the finished product.

There will no doubt be deep coal from even earlier periods, there have been quite a number of greenhouse and likely super greenhouse periods in the past, the further back you go the sun was significantly cooler which helped offset it a little. The continental distribution was also different during the last major super greenhouse which will also have had significant effect on climate.

Yeah but most of the animals and a vast number of the plants that humans have domesticated bear little resemblance to their wild types even 10,000 years back.

I know you have a thing about livestock and effect on climate but personally I think the numbers add up overall.

The real problems are our energy use in our technological world, solve those and you could likely get away with the meat protein from animal farming business, there are choices to be made and at this point the solutions are all going to be some kind of technological intervention by humans.

I can't really agree with that one John as I think a great many people, scientists in one discipline or another are well aware that this is a complex interconnected dynamic system.

I would agree that this statement applies to a great many of the qualified and vocal prominent climate science detractors who seem intent on trying to exclusively promote their personal interpretation but I think the majority of professional scientists working directly in climate science are taking a pretty holistic view of the situation and fully understand how complex and dynamic a system life on earth represents.

Climate is a chaotic system pushing it here prodding it there can and will result in strange kinds of immediate or delayed feedback and outputs, no one on earth has sufficiently comprehensive mathematical models to represent the real world at close to 99.99999% fidelity they just don't, look at weather models the best you can get with the current models is about 5 days accurate forecast with the accuracy decreasing rapidly as you push the forecast boundary a day or two or three into the future, accurate detailed predictions of tomorrow's weather and next week's weather is impossible however a great many people want to believe that it should be possible and that it is just those dumb scientists and mathematicians who can't work it out.

Those people who desire that certainty are usually unwittingly adhering to Pierre Laplace's notion of causal determinism the notion that with precise knowledge of pre-existing state classical mechanics could predict the exact future state and outcome of any prior system, sadly we now know that such knowledge is forever hidden from us, however this does not prevent us constructing models that accurately represent trends and it does not prevent extremely valid input from the work of palaeoclimatologist's and geologists, the understanding of past climate scenarios is extremely important particularly with regards to that hockey stick graph you mentioned because it is your field that provides the evidence that demonstrates the somewhat unique timescales involved in this particular modern climate event.

If you take events like the flood basalts that transformed the world and which made it a virtual hell and caused one of the greatest mass extinctions ever, that happened over a couple of million years, anthropogenic climate change is happening over a couple of centuries it's the rate of change that is unprecedented and there are a multitude of factors feeding into that rate of change including agriculture and livestock.

Expansion of livestock has particularly in recent times been at the expense of forested land, loss of those forests today in South America as well as elsewhere is not just a simple carbon equation there is real danger to the biodiversity of life the world in most cases we don't actually know what we are losing because we never got to discover it in the first place, so it's a bigger issue than just talking about climate even though climate is the Elephant in the room.

How much of the world’s land would we need in order to feed the global population with the average diet of a given country? - Our World in Data




I've said already that I think it is all too late anyway, we won't do enough to prevent significant catastrophe and that catastrophe will reduce the total usable habitable land significantly, the cows unwittingly will have had their somewhat small part to play in this but really they are not that relevant as it is human industrial activity and the use of fossil sunlight that will have brought about this disaster, habitable land will decrease and as a result both agriculture and livestock will eventually decrease and so will the human population at some point because teh planet simply won't be able to support them.

And remember that the mitigating actions, in terms of power supply, that we want to take are going to need a lot of that land particularly for solar, in some locations we might get away with using the barren land for that but that barren land is going to expand as a direct result of climate change.

Climate a highly complex chaotic system easily disturbed by very small input changes.