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Hothouse Earth - Trajectories of the Earth System in the Anthropocene

climate changes existential risks

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#1 albedo

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Posted 22 March 2019 - 03:16 PM


If credible, are we wise enough to avoid this ?

 

"...Our analysis suggests that the Earth System may be approaching a planetary threshold that could lock in a continuing rapid pathway toward much hotter conditions—Hothouse Earth. This pathway would be propelled by strong, intrinsic, biogeophysical feedbacks difficult to influence by human actions, a pathway that could not be reversed, steered, or substantially slowed. Where such a threshold might be is uncertain, but it could be only decades ahead at a temperature rise of ∼2.0 °C above preindustrial, and thus, it could be within the range of the Paris Accord temperature targets. The impacts of a Hothouse Earth pathway on human societies would likely be massive, sometimes abrupt, and undoubtedly disruptive. Avoiding this threshold by creating a Stabilized Earth pathway can only be achieved and maintained by a coordinated, deliberate effort by human societies to manage our relationship with the rest of the Earth System, recognizing that humanity is an integral, interacting component of the system. Humanity is now facing the need for critical decisions and actions that could influence our future for centuries, if not millennia (88). How credible is this analysis? ..."

 

Attached File  Hothouse Earth.PNG   264.75KB   0 downloads

 

Steffen W, Rockström J, Richardson K, et al. Trajectories of the Earth System in the Anthropocene. Proc Natl Acad Sci USA. 2018;115(33):8252-8259.


Edited by albedo, 22 March 2019 - 03:30 PM.


#2 Mind

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Posted 22 March 2019 - 04:48 PM

All of the talk about the "point of no return", "irreversible", etc... is not based upon reason, just fear-mongering.

 

1. If humans caused a "hot house" earth, then it can certainly be reversed by humans. There is no known physical law that would prevent humans from reversing what has been done so far - given enough effort. Blocking sunlight is just one simple solution that could be done on a small budget and reverse temperatures on a very short time frame.

 

2. Our technological capabilities increase every year. People who constantly claim "we are all doomed", have zero imagination or any grasp of technological progress.

 

3. There has been a "hot house" earth before (and a snowball earth). It most certainly reversed - so there is historical evidence that it is NOT irreversible.


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#3 albedo

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Posted 23 March 2019 - 09:28 AM

...given enough effort...

 

Yes, that is the key point as the authors also say in the text I quoted.

 



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#4 platypus

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Posted 23 March 2019 - 11:39 AM

All of the talk about the "point of no return", "irreversible", etc... is not based upon reason, just fear-mongering.

 

1. If humans caused a "hot house" earth, then it can certainly be reversed by humans. There is no known physical law that would prevent humans from reversing what has been done so far - given enough effort. Blocking sunlight is just one simple solution that could be done on a small budget and reverse temperatures on a very short time frame.

That is incorrect - some of the changes are irreversible in the human timescale so there is no way to return to the past climate. Blocking sunlight does not reverse the changes caused by extra greenhouse-gases, but nudge us towards a cooler but different climate. Also the sea-level changes are largely irreversible as it is slower to add mass back to the large ice-sheets than to remove it (which is currently taking place).


Edited by platypus, 23 March 2019 - 11:46 AM.

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#5 pamojja

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Posted 23 March 2019 - 02:05 PM

Must by my cold-intolerance, or my love of tropical climates, that I fear much much more the end of the inter-glacial. But maybe I don't fear the hot-house as much because I did already what I could to not make it progress (examples: not consuming meats, already since age 20 never owned a private car again, in general keeping my energy foot-print low..)

 

But in  general we are not wise enough..


Edited by pamojja, 23 March 2019 - 02:07 PM.


#6 Oinen

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Posted 30 March 2019 - 08:51 PM

Look at pictures of water levels from 100 years ago at lighthouses, etc.

Look at the same areas today.

No change.

What is the solution that is always paraded for this 'crisis?' Giving money. More taxes - no discussion of what would ACTUALLY fix these issues - such as the construction of carbon scrubbers. Why don't they ever discuss what would ACTUALLY fix these supposed issues?

Why do all their models ignore the most potent greenhouse gas that exist - a gas that literally influences weather patterns in measurable ways day by day? Water vapor.

Why are the biggest polluting countries never criticized, such as China and India? Because the mainstream narrative about this isn't based on science. It has been completely politicized. If you don't toe the line as a climate scientist and even dare to question or think critically about this, you get your grants pulled. That's science? No. That's tyranny behind the guise of 'science'.

You can make prediction models say whatever you want when you omit certain information.


Edited by Oinen, 30 March 2019 - 08:52 PM.

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#7 platypus

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Posted 30 March 2019 - 10:36 PM

Why do all their models ignore the most potent greenhouse gas that exist - a gas that literally influences weather patterns in measurable ways day by day? Water vapor.
 

If you believe that to be the case you are very gullible....read blogs much? 



#8 Oinen

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Posted 30 March 2019 - 10:37 PM

When all variables aren't accounted for, then it is junk science. Again - you can make prediction models say whatever end-result you want by fudging the data, and most of the time the fudging is by omitting stuff like this.

Interesting that you are unable to actually address what I said and instead go into attack mode.


Edited by Oinen, 30 March 2019 - 10:39 PM.


#9 platypus

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Posted 30 March 2019 - 11:22 PM

Let's see: 

 

- Atmosphere is warming up fast while most of the heat has gone into the oceans 

- Land ice (ice sheets, glaciers) is melting globally, fast

- Global sea ice volume is on a rapidly diminishing trend

- Sea level rise is accelerating

 

None of this seems to be "normal variation", but something faster and more sinister. The culprits are pretty clear at this point. 

 



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#10 Oinen

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Posted 30 March 2019 - 11:57 PM

"- Sea level rise is accelerating"

Possible, but hasn't been proven as man-made.


The Cove in La Jolla, 1960

https://climateinsid...ollacoveold.jpg

Today:

https://climateinsid...ajollacove1.jpg

 This has been repeatable for locations all over. It doesn't seem as extreme as many 'scientists' have said.


"
Atmosphere is warming up fast while most of the heat has gone into the oceans "

It takes fudging the climate data to 'prove' this is man-made. This wasn't a result of humans.


Anyways, the only countries actually addressing limiting carbon emissions are first word countries. Until countries like China and India are held accountable, it really doesn't matter. Technology will continue to improve, reducing emissions naturally as has already happened in the US. When the countries that are the biggest producers of greenhouse gasses are not held accountable, that proves that it is all political. You will never hear politicians who support man-made climate change attempting to hold the biggest producers of greenhouse gasses accountable, proving it is nothing more than a political weapon for more taxes; for more kickbacks, so the politicians can line their own pockets.




https://www.epa.gov/...rst-year-office

 The climate always goes in cycles, and is always changing.

Anyways, a solar minimum is coming regardless. We are actually headed towards a mini-ice age (and the fear surrounding that is also overblown).


https://www.youtube....h?v=kBKJkU06ICQ

"Fastest-Thinning Greenland Glacier Threw NASA Scientists for a Loop. It's Actually Growing."
 

https://www.livescie...er-growing.html

It's also proven that climate scientists now ignore data that disproves the man-made climate change theory, because for some reason, if they start showing this data, their grants and funding get pulled. That isn't science.

"Science" is a joke these days. Something needs to use the scientific method, and it also has to be repeatable.

"According to [a] report, scientist and Wharton School Professor J. Scott Armstrong says that fewer than one percent of modern scientists use the scientific method. “We go through journals and rate how well they conform to the scientific method. I used to think that maybe 10 percent of papers in my field… were maybe useful. Now it looks like maybe one tenth of one percent follow the scientific method,” Armstrong said. “People just don’t do it.”

Also, if CO2 was able to control climate temperature as is always purported, this wouldn't be possible.

 

The 800 year lag in CO2 after temperature – graphed

http://joannenova.co...ice-core-graph/


Edited by Oinen, 31 March 2019 - 12:17 AM.


#11 Mind

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Posted 31 March 2019 - 11:49 AM

That is incorrect - some of the changes are irreversible in the human timescale so there is no way to return to the past climate. Blocking sunlight does not reverse the changes caused by extra greenhouse-gases, but nudge us towards a cooler but different climate. Also the sea-level changes are largely irreversible as it is slower to add mass back to the large ice-sheets than to remove it (which is currently taking place).

 

..."in the human timescale"

 

If anyone seriously believes that some sort-of hype-intelligence evolution is going to happen by 2029, or 2045 (or pick your near-term prediction), then rapidly developing clean energy, getting carbon dioxide out of the atmosphere, geo-engineering a stable climate, etc... will literally be "child's play".

 

I hope I don't disappoint too many that I am not on the "apocalypse" bandwagon. I am in the weather business, I read the studies, etc. I have heard that "global warming" was going to destroy the earth for 30 years now. Year after year after year after year after year after year after year after decade, after decade. What has happened during this time? From a material comfort perspective, it has never been better for human beings, by almost any metric you want to measure.

 

Some of the push back Armageddon-promoters receive is justified. Giving up prosperity in "the West" is a dumb idea. If Europe and the U.S. dropped everything and went back to the stone-age and had near zero carbon emissions, it would hardly matter....because China is the world's leading carbon and pollution producer...BY FAR...and increasing dramatically every year. Unbeknownst to many, carbon emissions in the U.S. have been dropping, now down to levels similar to the early 1990s. The U.S. is already doing a good job through innovation and clean-tech development. That is the path forward.



#12 platypus

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Posted 31 March 2019 - 12:33 PM

..."in the human timescale"

 

If anyone seriously believes that some sort-of hype-intelligence evolution is going to happen by 2029, or 2045 (or pick your near-term prediction), then rapidly developing clean energy, getting carbon dioxide out of the atmosphere, geo-engineering a stable climate, etc... will literally be "child's play".

Hyper-intelligence still cannot trump the laws of physics - it is not magic. But yes, perhaps hyper-intelligence can find a way of quickly reducing atmospheric greenhouse gases, which would indeed reverse much of the recent warming that is raising the oceans and melting shitloads of ice as we speak. 



#13 platypus

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Posted 31 March 2019 - 12:37 PM

The sea-level is tracked, globally, with satellite altimetry, and it's currently rising at 3+ mm per year and accelerating. Some point measurements of lighthouses on continents that themselves move with respect to the mean sea level does not prove jack shit. And like I said, land ice and sea ice are diminishing which together with the warming of the seas explains much of the measured sea-level rise. And "science is a joke these days" does not deserve much of a comment except that blog-science is not science so please forget everything you read on blogs to start with. 


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#14 platypus

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Posted 31 March 2019 - 12:43 PM

 

The 800 year lag in CO2 after temperature – graphed

http://joannenova.co...ice-core-graph/

This is a common one on denialist blogs (like joannenova) - they forget to mention that the extra CO2 has directly and measurably increased the greenhouse effect (it is visible in the emission spectrum of the sky, and of the planet, exactly as predicted). That is one of the smoking guns. 



#15 platypus

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Posted 31 March 2019 - 12:45 PM

I hope I don't disappoint too many that I am not on the "apocalypse" bandwagon. I am in the weather business, I read the studies, etc. I have heard that "global warming" was going to destroy the earth for 30 years now. Year after year after year after year after year after year after year after decade, after decade. What has happened during this time? From a material comfort perspective, it has never been better for human beings, by almost any metric you want to measure.

Well, I'm in the satellite Earth observation business and oh boy, there are tons of changes that took place in the last 30 years, some of which are worrying. 



#16 Mind

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Posted 31 March 2019 - 01:22 PM

Well, I'm in the satellite Earth observation business and oh boy, there are tons of changes that took place in the last 30 years, some of which are worrying. 

 

Then you are probably aware the Antarctica is gaining ice mass, not losing. https://www.nasa.gov...er-than-losses/

 

However, experts are divided as to whether or not this will continue. Currently, precipitation is adding more ice mass to Antarctica than is being lost through melting. I am unsure if there has been a study simulating (computer modelling) at what temperature the process would reverse.



#17 platypus

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Posted 31 March 2019 - 02:21 PM

Then you are probably aware the Antarctica is gaining ice mass, not losing. https://www.nasa.gov...er-than-losses/ (cheery

 

However, experts are divided as to whether or not this will continue. Currently, precipitation is adding more ice mass to Antarctica than is being lost through melting. I am unsure if there has been a study simulating (computer modelling) at what temperature the process would reverse.

Yes, that is the only single one of literally dozens of studies that concluded Antarctica was gaining mass - denialist blogs forget to mention that (cherrypicking). Since that time the losses from West Antarctic Ice Sheet (WAIS) have been growing so rapidly that that if that study was redone now with the same methods, even it would conclude Antarctica is losing mass. Antarctica is mostly losing mass by calving, not melting and some researchers believe WAIS has already entered slow but inevitable collapse. That would add several meters to sea-level in a few centuries - I think this scenario is very likely. There is no known method that could reverse this trend as it would require cooling sea-currents at depth. 



#18 Oinen

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Posted 31 March 2019 - 02:43 PM

This is a common one on denialist blogs (like joannenova) - they forget to mention that the extra CO2 has directly and measurably increased the greenhouse effect (it is visible in the emission spectrum of the sky, and of the planet, exactly as predicted). That is one of the smoking guns. 

The data provided on that site disproves that completely. It's charting CO2 and how it affects temperature over hundreds of thousands of years.

That's the problem with 'climate science' - data that shows the opposite of the 'apocalypse' is always dismissed regardless of the fact that it is actually valid.

Since you love satellite data, you would know that during the past 20 years, the earth has become much, much greener.

https://www.forbes.c...to-china-india/

 

Yes, that is the only single one of literally dozens of studies that concluded Antarctica was gaining mass - denialist blogs forget to mention that (cherrypicking). 


Reminds me of the cherry picking that the entire scientific establishment takes part in when studies come out, but are not published because they show the opposite of what the narrative is. This is a common theme with 'climate scientsits,' because if your work doesn't support the narrative, you tend to get your grants and funding pulled - no matter how valid your research is.

https://climatechang...hurricane-data/


Regardless, people will never take man-made climate change seriously until they talk about the actual culprits of the most pollution, such as India and China. They want to punish counties' that are actually measurably lowering emissions instead of talking about the real culprits.

Why isn't there a campaign among climate scientists to turn the deserts green? No, the 'solution' is always more taxes. More money for the politicians to line their pockets.

When politicians stoke fear to line their own pockets, you should probably question their intentions.


Edited by Oinen, 31 March 2019 - 02:57 PM.


#19 platypus

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Posted 31 March 2019 - 04:10 PM

Nope, perhaps it was not explained in the blogosphere that the fact that rising temperatures eventually raise CO2 does not in any way prevent rising CO2 increasing the temperature now. The latter has been measured directly -> direct proof. 

 

Earth Science does not "dismiss" any kind of data, so check your sources (forget blogs please). And regarding cherrypicking, the entire "climate-sceptic establishment" manages to publish around 10 articles per year globally, most of which are in 4th rate journals and instantly debunked. This is disgraceful but of course the relevance of the BS research is totally overblown in the blogosphere. BTW, do you have a problem with the scientific evidence for evolution? 



#20 Oinen

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Posted 31 March 2019 - 04:19 PM

Very interesting that you never post sources.

Also very interesting that you continue to debase, look down upon, and attack. In the end, it doesn't even matter if you are actually right, because with that attitude, nobody is going to take you seriously. Truth can stand on its own without your elitism, which means it isn't the truth if you can't let the facts stand for themselves.

Evolution has a hell of a lot more validity than what you're pushing. Entire cities were supposed to be underwater by now, where is that? Again - you keep ignoring the most inconvenient ( to you ) parts of the argument as well.

-Why don't we hold the biggest polluters responsible?

-Why isn't there a campaign to turn the deserts green, if this is such an issue? That the survival of the human race depends on it?

-Why is the solution always more taxes? Throwing money at problems doesn't solve them - it just lines pockets of politicians. The biggest, most vocal supporters of the man-made climate change theory tell the middle class to hold themselves responsible, yet they NEVER hold the biggest polluters responsible? It just isn't logical.

If it is a real issue, then why aren't solutions that would actually solve the problem EVER proposed?

Also, why do you ignore things which completely show that, even if you're right, it doesn't matter, such as the coming solar minimum?




"According to [a] report, scientist and Wharton School Professor J. Scott Armstrong says that fewer than one percent of modern scientists use the scientific method. “We go through journals and rate how well they conform to the scientific method. I used to think that maybe 10 percent of papers in my field… were maybe useful. Now it looks like maybe one tenth of one percent follow the scientific method,” Armstrong said. “People just don’t do it.”

The elephant in the room: fewer than one percent of modern scientists use the scientific method


Edited by Oinen, 31 March 2019 - 04:26 PM.


#21 platypus

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Posted 31 March 2019 - 05:06 PM

I'm personally not that interested in policy or "solutions". I'm just dismayed to see what kind of bullcrap is fed to the masses on denialist sites like WUWT etc. Perhaps top-level science is "elitist", dunno? 


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#22 Oinen

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Posted 31 March 2019 - 06:36 PM

If the majority of your discussion isn't about spreading possible solutions, then it just isn't helpful. It builds a negative outlook of life that likely also affects your outlook on other topics. Why does anything matter if we're all going to die? That's a dark road.

Yes, academia is very elitist these days, and it is unfortunate. Objective discussion is basically impossible, which will probably destroy human society far before any climate issues destroy it because it prevents discussing topics from every angle.

Thankfully I believe that AI will be able to solve these issues before we destroy ourselves, because they will be able to compile all the variables and analyze them in a way that the human mind can never hope to do - free from emotional bias, which everyone is a victim of without realizing it. My distrust of authority biases me one way, and your more trusting stance of authority biases you in another.

I think the assumption has generally been that academic circles are free from emotional bias, but this isn't true and without recognizing this variable, it has probably harmed scientific progress in a variety of fields. People see what they want to see.


Edited by Oinen, 31 March 2019 - 06:45 PM.


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#23 platypus

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Posted 31 March 2019 - 07:25 PM

Nothing is free of bias but 95%+ of science has no trouble recognising humans are warming up the planet. I get it that born-again creationists cannot accept this, but why is it so hard for the rest of the US right-wing to face reality? Science is still by far the best method there is for figuring out truths. If the truths do not agree with someone's religion...well too bad. 


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#24 Mind

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Posted 31 March 2019 - 09:08 PM

I posted a very well-done study by a respected researcher. You can say it is probably meaningless, but that is just your opinion. Post a couple of studies that show a definitive loss of ice mass on Antarctica, that would be better.



#25 Oinen

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Posted 31 March 2019 - 10:42 PM

I get it that born-again creationists cannot accept this, but why is it so hard for the rest of the US right-wing to face reality? Science is still by far the best method there is for figuring out truths. If the truths do not agree with someone's religion...well too bad. 

Huh?

Wait... when did right wing and religion enter the conversation?? You'll fall back on pointless, baseless attacks before objectively talking about subjects, apparently.

You keep avoiding the topics that you cannot refute and pretending that makes your position still a strong one - just by ignoring the facts that disprove your position.

You continue to make claims without even attempting to back them up beyond your word.

Contrary to your belief, your word doesn't actually mean anything when you won't back it up.

It's like you don't even know what science is. Science has to be repeatable, use the scientific method (which less than one percent of scientists currently use)... it's like you're some sort of actual science denier.

When the current methodology of man-made climate change is disproven with actual factual data omitted, such as ice core samples (the man-made climate change hypothesis is only based on a couple hundred years of data and ignores everything before that), then it is junk science based on a false premise.


Edited by Oinen, 31 March 2019 - 10:44 PM.


#26 platypus

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Posted 01 April 2019 - 12:05 PM

I posted a very well-done study by a respected researcher. You can say it is probably meaningless, but that is just your opinion. Post a couple of studies that show a definitive loss of ice mass on Antarctica, that would be better.

This one is from a great community-effort:

 

https://www.nature.c...1586-018-0179-y

 

https://orbi.uliege....Nature_2018.pdf

 

Over this period, ocean-driven melting has caused rates of ice loss from West Antarctica to increase from 53 ± 29 billion to 159 ± 26 billion tonnes per year; ice-shelf collapse has increased the rate of ice loss from the Antarctic Peninsula from 7 ± 13 billion to 33 ± 16 billion tonnes per year. We find large variations in and among model estimates of surface mass balance and glacial isostatic adjustment for East Antarctica, with its average rate of mass gain over the period 1992–2017 (5 ± 46 billion tonnes per year) being the least certain.


Huh?

Wait... when did right wing and religion enter the conversation?? You'll fall back on pointless, baseless attacks before objectively talking about subjects, apparently.

You keep avoiding the topics that you cannot refute and pretending that makes your position still a strong one - just by ignoring the facts that disprove your position.

You continue to make claims without even attempting to back them up beyond your word.

Contrary to your belief, your word doesn't actually mean anything when you won't back it up.

It's like you don't even know what science is. Science has to be repeatable, use the scientific method (which less than one percent of scientists currently use)... it's like you're some sort of actual science denier.

When the current methodology of man-made climate change is disproven with actual factual data omitted, such as ice core samples (the man-made climate change hypothesis is only based on a couple hundred years of data and ignores everything before that), then it is junk science based on a false premise.

You quoted some dude saying 99% of scientists do not do science today. That is pure anti-science propaganda.



#27 platypus

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Posted 01 April 2019 - 12:08 PM

When the current methodology of man-made climate change is disproven with actual factual data omitted, such as ice core samples (the man-made climate change hypothesis is only based on a couple hundred years of data and ignores everything before that), then it is junk science based on a false premise.

I think you should read the IPCC AR5 WG1 report and see how wrong your statement about ice-cores or "ignoring everything before a few hundred years" are. You are making many incorrect claims based on (presumably) stuff floating in the climate denialist blogosphere. 



#28 maxwatt

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Posted 01 April 2019 - 02:56 PM

Last night I heart Michael Mann speak at the Shokan Center (it was a Climate Reality Conference, talk open to the public)

 

Not sure what I expected, but he is not a doom and gloom Casandra.

Nor is he complacent.  He discussed the various climate models (and yes they factor in water vapor.  And methane. Someone has been reading too much petro-company propaganda )  The models keep getting better as they find new factors and learn from mistakes.  But they are proving inaccurate in that they are UNDER estimating the amount of sea level rise from warming.  Greenland and East Antarctica are losing ice much faster than predicted, due to ice cliff instability - an ice cliff collapses once it reaches a certain height.  And due to crustal compression from the weight of a glacier, the glacier's base becomes deeper under an ice sheet... so as the glacier retreats, the cliff gets taller until it collapses suddenly.  IF we lose the Greenland Ice Sheet, it's likely a foot or two of sea level rise; Thwaites, another three feet.  Possibly by 2050.  West Antarctica could follow if Thwaites collapses, as the land ice flows unimpeded into the sea.  That could be 10 or 12 feet (cummulative or additive, wasn't clear.)  Paleoclimate studies have indicated that ice collapse was extremely rapid in the past, decades not centuries.

 

I was surprised how optimistic the man was; he feels that the political changes that are afoot that will enable even more rapid introduction of carbon-free technologies can within a decade or two bring us to the point that the planet's natural carbon sequestration processes will handle what we continue to emit. 

But the ice we lose will stay lost on a geologic time scale - thousands of years.



#29 platypus

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Posted 01 April 2019 - 05:41 PM

IF we lose the Greenland Ice Sheet, it's likely a foot or two of sea level rise; Thwaites, another three feet.  Possibly by 2050.  West Antarctica could follow if Thwaites collapses, as the land ice flows unimpeded into the sea.  That could be 10 or 12 feet (cummulative or additive, wasn't clear.)  Paleoclimate studies have indicated that ice collapse was extremely rapid in the past, decades not centuries.

 

(.....)

 

But the ice we lose will stay lost on a geologic time scale - thousands of years.

Greenland is about 6 meters in mean sea level I think but will take some millennia even in the fastest scenarios. Still, it's possible Greenland mass-loss accelerates from the present situation, time will tell. Thwaites/WAIS is several meters as well and could happen much quicker due to marine ice-sheet instability. 



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#30 Mind

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Posted 01 April 2019 - 06:04 PM

Personally, I think the likelihood of the earth getting warmer is high, however, the sun activity is a wildcard. It is loosely correlated with other cooling periods, Unfortunately, it is difficult to discuss without being labeled as a "stupid denialist".

 

As I mentioned earlier, I have heard "the earth is going to be destroyed" (very literally) for 30 years. I have to tune it out. Better to focus on positive methods of lowering our impact, instead of "we are all doomed!!!!".







Also tagged with one or more of these keywords: climate changes, existential risks

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