Water vapor (clouds) is a stonger greenhouse gas than carbon dioxide. We already got measurably higher temperatures, so we also have higher water evaporation, and from the last 5 years it looks like it happens every year.
So the runaway is already happening, until something stops it near hothouse conditions or hopefully earlier than that.
> Policymakers and the public, however, remain largely unaware of the risks posed by such a practically irreversible transition
Most people still underestimate what it means for the earth system to change from the current stable state into another state, which might need many years to become stable again. And that new stable state might be a lot less favourable for us humans.
People really fail to grasp the significance of this part.
One of our most common apocalyptic fantasies lays this out quite well: nuclear annihilation. The common narrative is about the post-apocalyptic world and rebuilding. But this presumes a new normal has been established.
With climate change we will continue to experience more extreme changes at a faster rate over time with no chance of a "new normal" in our lives.
It took hundreds of thousands of years for humans to develop agriculture. It's no coincidence that this development happened during one of the most stable periods of climate the planet has ever seen. People love to wax poetic on human adaptability, but we were effectively playing on "easy" mode.
While the other side of climate change might be a more hostile earth, the transition period will be worse because you can't adapt. In our lifetimes we may live to see a period of record heat waves in Europe, followed by a transition of Europe to that is dramatically colder (and who knows, maybe back again).
The other major problem is as stability decreases so does our ability to predict the future. It's hard to even know what we might be facing in the coming years, but high variance is usually not great for complex life.
Are there any attempts to start geo-engineering to fix this? I'm assuming there will be no attempt to stop dumping carbon into the atmosphere, can we at least do something to take it back out? Can we use solar or renewables to possibly do that at scale?
I don't think carbon capture / sequestration is going to do enough, but if we continue slipping into this trajectory I think there will be more support for changing reflectivity (spraying sea water, or putting particles in the stratosphere).
Go ask Google about China and the 3rd world contribution to global pollution. The West is bending over backwards to 'fight climate change' and a huge chunk of the world is just doing whatever they want, completely negating all of the west efforts.
As a 52 year old who never believed we would take climate change seriously (and who is more convinced than ever I was correct as society actually regresses on this issue) I did what I had to do -- I purposefully didn't have children.
Good luck to those of you who did.
This ain't my problem. I'll be dead (or close enough) when the shit fully hits the fan and won't have doomed any offspring to the upcoming migration/resources wars
this is like a tiktok rage bait way of thinking. western nations have largely peaked on carbon emissions. china is slowing down and will peak soon. there are a lot of countries that still are growing in emissions, sure, but you are not looking at this scientifically.
If you are a US citizen, voting Trump out might be unironically the most significant decision your country could make for the next 100 years of mankind.
Not because the alternative is so great, but because Trump is so horrible that it's not even a question. We really don't need someone who doesn't even acknowledge climate change in charge of the world's biggest economy.
There are actions you can cheer on, like China's quick adoption of renewable energy. You can't make it happen yourself but you can bring peoples' attention to good things, encourage those within your circle of influence, and vote for representation that shares your views.
As for what "we" collectively can do... let's assume you are speaking of areas of research. We may need to focus on researching adaptation techniques for the areas that are going to be the hardest hit, or that have the fewest resources to cope. It's a sad topic but it may be needed. Assume the worst, hope for the best, and plan for what you can.
The answer to that question is always the same. Join a party and become politically active. Or, if you really can't find any party that represents your views, join an NGO and become active in it. If you're too lazy for that, consider paying an NGO that does spectacular actions that have a public impact. And never vote for any parties that don't do anything for better climate control, of course.
Seems China is cooking atm. If solar power and battery tech continues at this speed and their nuclear ambitions pan out, fossil fuels will be economically non-competitive (if they aren’t already). China EV momentum is incredible.
So still some hope I think! And it’s possible the populist “dumb dumb bricks” crew will decline in popularity when the inevitable lack of tangible improvements continues. Though since we are dealing with dumb dumb it may take a while
It is important to keep reminding ourselves that climate change is a real problem for humanity and that each and every one of us contributes to its intensification or mitigation through our decisions. It is a problem that requires solutions, but implementing these solutions involves so much inertia that it can sometimes be painful.
And let's contrast that with the AI hype. It's more the opposite, a kind of solution to problems we didn't really have, but are now being persuaded we do. It would be sensible to invest an equal share of the resources currently being pumped into AI with uncertain outcomes into the complex issue of climate change. And, no, AI won't solve it; unfortunately, it only makes it worse.
The difference is emblematic of the difficulty in getting attention for climate mitigation. AI succeeds because you can sell a service to an individual human which will give them advantages over other humans. Climate change mitigation fails because you are trying to sell a service to humanity which will result in a better end state over some other hypothetical imagined future. Humans make decisions, not humanity, and many of them are pretty bad with both hypotheticals and imagination. It's no wonder that a product designed to make them do better at what they do, right now is more successful than one designed to make everybody do better than what would otherwise have resulted, 50-100 years in the future when they'll likely be dead.
Any kind of workable solution to large, societal-level problems needs to deal with the principal agent issue. Society doesn't actually exist; humanity doesn't actually exist. These are abstractions we use to label the behavior of individual people. You need to operate on the level of individual people to get any sort of outcome.
(FWIW, this is a major reason why concepts like markets, capitalism, democracy, rule of law, and federalism have been successful. They work by aligning incentives so that when one person takes an action that is good for themselves, they more-or-less end up benefitting the people around them too.)
Imagine if we had laws that required all LLM compute to come from solar, or other sustainable power sources. We could have used the market's thirst for AI as a backchannel way to force creation of new sustainable energy.
In contrast to Elon/XAI's illegal methane fuled datacenter in memphis
I agree to an extent that each of us contributes in a manner, but the manner that we contribute is not certain. A person who puts more effort into reducing their own personal climate impact could be doing worse than using the same effort to enact systemic change. It could be bailing water on a sinking ship instead of fixing the leak. The problem is you might not appear to be doing anything in isolation. Just spending that extra effort at work and sending the money earned to the ship patching people so they can get what they need would fix the problem better. If you choose bailing are you not just choosing something visible but ineffective over achieving the desired outcome but just being a boring taxpayer.
As for AI, to characterise it as a "solution to problems we didn't really have" is placing your opinion over others. They may be right or wrong about it but many AI proponents firmly believe that AI can provide solutions to real world problems that we definitely have. You may disagree about their potential effectiveness, and that's ok, but at least tolerate that people might have different ideas about how to make the world better.
There simply is no solution to this problem. We would all need to stop driving, flying, and eating meat. Most families (in the US, anyway) would suffer unemployment and starvation if they couldnt drive to work.
Humans will continue to do whatever is needed to survive,, and that currently involves driving, flying, and eating meat. They will only stop when those behaviours are either not possible, or hinder survival.
every year (month?) that passes people are saying the end of the world is right around the corner due to climate change. then 10 yrs passes, nothing happens, and they keep saying the same stuff.
the system warning you the world is in big trouble dont remind you 'their side' has been saying the sky is falling for ~40+ yrs.
> that each and every one of us contributes to its intensification or mitigation through our decisions
I‘ve travelled quite a bit and I find it hard to convince myself that I as a city dweller contribute any meaningful amount to pollution or waste. I‘ve seen rivers of trash flow directly into the ocean. The rich and wealthy pollute disproportionally in such a way that I don‘t think offloading the responsibility to the general public is fair.
It's important to remember that in REALISTIC worse case emissions projections, by 2050 - we will have CO2 higher than levels seen in the last 10 million years - but there was a 500 million year period where CO2 levels were an order of magnitude higher than that - and there's NO WAY we're getting there without destroying civilization first, so there's no chance on current trajectories that we turn the planet into Venus.
The super danger zone is ~1000 PPM CO2 - where ocean chemistry changes. In worst case scenarios in 50-60 years, we could get there - but there's a lot of reason to believe we won't, and we DEFINITELY aren't getting there by 2050.
Saying we're on a "hothouse" trajectory plays into the Apocalypse / Earth Becomes Venus trope, which is so ridiculous for our lifetime even under the absolute worst case realistic scenarios.
> It is important to keep reminding ourselves that climate change is a real problem for humanity and that each and every one of us contributes to its intensification or mitigation through our decisions.
Which decisions though? The decisions to hold back nuclear, NIMBY solar, or keep cheap Chinese EVs out of the hands of consumers have a much bigger impact than whether you leave the lights on. Freezing in place with our existing fossil fuel system and fearfully minimizing our consumption will at best only slightly slow our decline.
IMHO, we must rise above fearful, superstitious individual moralism and boldly apply ambitious zero carbon energy science, engineering and policy, including fission (to keep things going in dark winters) and possibly even geoengineering (pending extensive research and small-scale pilots).
We cannot afford continued reflexive, neurotic rejection of any deviation from the status quo as we approach these tipping points. Continuing exactly as we are is not safe, nor can we return to preindustrial society. We need to build zero carbon supply for the needs of civilization. Including the stuff that people are uncomfortable with out of ignorance.
We need a plan. Neurotic criticism of every realistic plan is not a plan.
We cannot afford a continued overhang of 1970s Boomer environmentalist sentimentalism. Scientific engineering of the future is needed, not ideological nostalgia for an idyllic past we can no longer return to.
AI may not do much good directly, but it has the salutary effect of making rich tech companies care about electrical supply and distribution, accelerating the learning curve towards cheap supply.
> each and every one of us contributes to its intensification or mitigation through our decisions.
How on earth would anyone contribute to its mitigation? Of course everyone, everyone, contributes to its intensification, no matter how "green" they are. Yes of course, people contribute to the intensification in wildly different degrees.
Framing man made climate change - aka the 6th mass extinction event - as a problem in search of a solution is by itself the very reason we won't "solve" it.
Trying to solve climate change in anything but a very narrow sense is like trying to perform humane torturing. One can either treat others humanely _or_ torture them. The two at the same time is impossible. The majority of conversations around climate change focus on doing the same things - modernity - but without the negative effects. Chasing a way to humanely torture children will not in fact stop the torturing of children. The goal is wrong! No amount of "solutions" will help you if they all aim to achieve the goal that itself is the root cause of the issues.
The major road blocks for solutions has been unchanged for the last decades. The same strategy talked about at the beginning of the 21st century still has the same problems, and while more people are aware of climate change, we are only further away from creating and implementing solutions.
Taking Europe as an example, the main strategy is still to use the combination of natural gas, biofuels created from farming corn, and renewables to enable electrification. This strategy lacks both scientific and political consensus among the people who believe in climate change. The result is that as strong one side of the same movement are pushing for it, the other side is also pushing against it. We see the exact same thing with the other major strategies involving tree planting and changes to the culture (diet).
Until the problem is politically recognised by the masses with adequate concern there will be no change. Climate collapse is not a problem for the capital and the elites it’s only a problem for the masses, but getting the masses to understand that requires higher levels of complex system understanding and third and fourth order effects - something which is not a majority trait.
I fear the only solution to this is that a climate correcting perverse incentive materialises, such as fusion at scale being more profitable than fossil fuels, but without mass-panic induced traits such that fission has.
Unless the fake reality starts to crack with the Epstein and other current events and humanity's coming of age will happen. Even if a hundred years later than Bonhoeffer though it would.
We can't cut emissions fast enough politically, but we can race towards economically viable fusion power which would solve the problem from the supply side and would make industrial scale carbon sequestration not insane, for a century or so, until waste heat itself can't be radiated fast enough even in 250 ppm CO2 atmosphere - but that's a problem for the XXII century.
Economically viable fusion power uses the fusion reactor in the sky beaming energy to us for free that we can collect with relatively cheap, simple, decentralized, solid state, and extremely long lasting (decades) power transmission recievers.
I really think the key to addressing climate change should have started 20 years ago in a lot of primary schools, whereby the curriculum includes subjects that are more tailored to solving problems with capturing or converting C02 (eg sciences) so that these students are thinking about these problems when graduating and starting businesses to solve the challenges (hopefully with gov incentives at same time).
20 years ago was when Al Gore’s influential documentary An Inconvenient Truth first appeared. Almost everyone I knew discussed it, including primary school pupils. Guess what, we do have better tools today than 20 years ago to fight climate change, such as practical and useful electric vehicles to replace CO2-emitting conventional vehicles.
What is generally not understood is that our current icehouse phase is rare.
'A "greenhouse Earth" is a period during which no continental glaciers exist anywhere on the planet... Earth has been in a greenhouse state for about 85% of its history.
'Earth is now in an icehouse state, and ice sheets are present in both poles simultaneously... Earth's current icehouse state is known as the Quaternary Ice Age and began approximately 2.58 million years ago.'
And yet, the only reasonable action to take is to flag this topic and move along with the "humanity has always found a way out, technology will save us. Remember, we were supposed to drown in horse manure!"
Why? Because candidly looking at those risks as a society means deep collective existential dread, which automatically means an immediate civilizational collapse.
So I'm guessing some of our elite is actually ignorant and the other part is willfully shutting the hell up on this subject to let our civilization run on fumes a few more years.
It's unfortunate because a rapid civilizational collapse could give humanity as a species a better chance of survival.
If only there was a clean, nearly limitless source of energy, where the waste for hundreds of years of energy could be stored in less than a square kilometer.
If such a thing existed, we could be sure that environmentalists and leftists would have openly embraced it, rather than nip it at the bud 50 years ago. Because they are Good People™. And we should definitely listen to them now because they Follow The Science™.
But that source of power is a high-modernist invention that is unnatural and especially dangerous because of a few high-profile accidents. We have to shut it all down!
People may be downvoting you because they think you're not speaking in good faith. But I think this touches on an important issue which is the credibility of politicians when it comes to bringing the science hammer down (in the form of policy). Stuff like the junk science behind those old CA plastic straw policies, the seesawing on Covid prevention and lab-leak denialism, the energy efficient dryers that don't work (this last one is more hearsay to me, and issue of CBA rather than scientific fact perhaps.) I think if politicians can get their shit straight on communicating mature science thoroughly and accurately it could go a long way to getting people to work together.
What's fascinating and dismaying to me is that it's obvious that there exists sufficient capital and capability in the west to fix this.
I always wondered if we just lacked the ability to mobilize to solve big problems anymore but now I look at this 7% US GDP being allocated to AI datacentres and I realize that it isn't a lack of ability, it's a lack of desire.
Imagine if we had ram shortages because all the silicon was being diverted towards making solar panels. Imagine if we had copper shortages because it was going to the windings on wind mills. Imagine if all these economic disruptions were just temporary and for a better cause or eliminating carbon emissions and eventually moving to sequestration of carbon.
Instead we get chatbots. And funny picture makers.
Meanwhile all these other AI threads everybody’s worried about losing their jobs
Not realizing we’re gonna go extinct here in the next thousand years unless something solves it
Since humans are incapable of doing this there’s only one possible option: To create something smarter than us and give it the power to solve it because we cannot
>Despite decades of research and sophisticated computational climate modeling, the magnitude and pace of these events have surprised scientists, raising questions about how well current climate projections capture risk.
"Yet again, worse than we predicted."
When this always-revise-in-one-direction phenomenon happened with the electron charge, it was considered a priori "proof" that scientists were fudging their data to match expectations. The Millikan Oil Drop Experiment is still studied in fundamentals of science class.[0]
If climate scientists are constantly revising their predictions upward, then this is equally "proof" that climate scientists are under pressure to revise their estimates downward. Far from being "alarmist," such terms are actually cudgels used to discourage climate scientists from making their data look too bad.
The result is the predictable fudging of climate data to look better than it really is.
At least considering only temperature, it seems changes are never going to be irreversible since both stratospheric aerosol injection and intentional nuclear winter should always be able to cool down global temperatures
74 comments
[ 3.1 ms ] story [ 71.6 ms ] threadWater vapor (clouds) is a stonger greenhouse gas than carbon dioxide. We already got measurably higher temperatures, so we also have higher water evaporation, and from the last 5 years it looks like it happens every year.
So the runaway is already happening, until something stops it near hothouse conditions or hopefully earlier than that.
> Policymakers and the public, however, remain largely unaware of the risks posed by such a practically irreversible transition
Most people still underestimate what it means for the earth system to change from the current stable state into another state, which might need many years to become stable again. And that new stable state might be a lot less favourable for us humans.
People really fail to grasp the significance of this part.
One of our most common apocalyptic fantasies lays this out quite well: nuclear annihilation. The common narrative is about the post-apocalyptic world and rebuilding. But this presumes a new normal has been established.
With climate change we will continue to experience more extreme changes at a faster rate over time with no chance of a "new normal" in our lives.
It took hundreds of thousands of years for humans to develop agriculture. It's no coincidence that this development happened during one of the most stable periods of climate the planet has ever seen. People love to wax poetic on human adaptability, but we were effectively playing on "easy" mode.
While the other side of climate change might be a more hostile earth, the transition period will be worse because you can't adapt. In our lifetimes we may live to see a period of record heat waves in Europe, followed by a transition of Europe to that is dramatically colder (and who knows, maybe back again).
The other major problem is as stability decreases so does our ability to predict the future. It's hard to even know what we might be facing in the coming years, but high variance is usually not great for complex life.
People are selfish. "Life will be much harder, and the problem will never be fixable within the rest of your life or your childrens' lives"
I don't know what to do.
As a 52 year old who never believed we would take climate change seriously (and who is more convinced than ever I was correct as society actually regresses on this issue) I did what I had to do -- I purposefully didn't have children.
Good luck to those of you who did.
This ain't my problem. I'll be dead (or close enough) when the shit fully hits the fan and won't have doomed any offspring to the upcoming migration/resources wars
Not because the alternative is so great, but because Trump is so horrible that it's not even a question. We really don't need someone who doesn't even acknowledge climate change in charge of the world's biggest economy.
As for what "we" collectively can do... let's assume you are speaking of areas of research. We may need to focus on researching adaptation techniques for the areas that are going to be the hardest hit, or that have the fewest resources to cope. It's a sad topic but it may be needed. Assume the worst, hope for the best, and plan for what you can.
So still some hope I think! And it’s possible the populist “dumb dumb bricks” crew will decline in popularity when the inevitable lack of tangible improvements continues. Though since we are dealing with dumb dumb it may take a while
The idea that this current apocalyptic prediction is expected to be better than reality is... not comforting.
[0] https://news.ycombinator.com/item?id=46980353
And let's contrast that with the AI hype. It's more the opposite, a kind of solution to problems we didn't really have, but are now being persuaded we do. It would be sensible to invest an equal share of the resources currently being pumped into AI with uncertain outcomes into the complex issue of climate change. And, no, AI won't solve it; unfortunately, it only makes it worse.
Any kind of workable solution to large, societal-level problems needs to deal with the principal agent issue. Society doesn't actually exist; humanity doesn't actually exist. These are abstractions we use to label the behavior of individual people. You need to operate on the level of individual people to get any sort of outcome.
(FWIW, this is a major reason why concepts like markets, capitalism, democracy, rule of law, and federalism have been successful. They work by aligning incentives so that when one person takes an action that is good for themselves, they more-or-less end up benefitting the people around them too.)
In contrast to Elon/XAI's illegal methane fuled datacenter in memphis
As for AI, to characterise it as a "solution to problems we didn't really have" is placing your opinion over others. They may be right or wrong about it but many AI proponents firmly believe that AI can provide solutions to real world problems that we definitely have. You may disagree about their potential effectiveness, and that's ok, but at least tolerate that people might have different ideas about how to make the world better.
Humans will continue to do whatever is needed to survive,, and that currently involves driving, flying, and eating meat. They will only stop when those behaviours are either not possible, or hinder survival.
the system warning you the world is in big trouble dont remind you 'their side' has been saying the sky is falling for ~40+ yrs.
I‘ve travelled quite a bit and I find it hard to convince myself that I as a city dweller contribute any meaningful amount to pollution or waste. I‘ve seen rivers of trash flow directly into the ocean. The rich and wealthy pollute disproportionally in such a way that I don‘t think offloading the responsibility to the general public is fair.
The super danger zone is ~1000 PPM CO2 - where ocean chemistry changes. In worst case scenarios in 50-60 years, we could get there - but there's a lot of reason to believe we won't, and we DEFINITELY aren't getting there by 2050.
The graph the main source shows is cherry-picked. Look at this: https://co2coalition.org/facts/for-most-of-earths-history-it...
Saying we're on a "hothouse" trajectory plays into the Apocalypse / Earth Becomes Venus trope, which is so ridiculous for our lifetime even under the absolute worst case realistic scenarios.
Which decisions though? The decisions to hold back nuclear, NIMBY solar, or keep cheap Chinese EVs out of the hands of consumers have a much bigger impact than whether you leave the lights on. Freezing in place with our existing fossil fuel system and fearfully minimizing our consumption will at best only slightly slow our decline.
IMHO, we must rise above fearful, superstitious individual moralism and boldly apply ambitious zero carbon energy science, engineering and policy, including fission (to keep things going in dark winters) and possibly even geoengineering (pending extensive research and small-scale pilots).
We cannot afford continued reflexive, neurotic rejection of any deviation from the status quo as we approach these tipping points. Continuing exactly as we are is not safe, nor can we return to preindustrial society. We need to build zero carbon supply for the needs of civilization. Including the stuff that people are uncomfortable with out of ignorance.
We need a plan. Neurotic criticism of every realistic plan is not a plan.
We cannot afford a continued overhang of 1970s Boomer environmentalist sentimentalism. Scientific engineering of the future is needed, not ideological nostalgia for an idyllic past we can no longer return to.
AI may not do much good directly, but it has the salutary effect of making rich tech companies care about electrical supply and distribution, accelerating the learning curve towards cheap supply.
I would like to note that the decisions we make at our jobs have the most impact.
How on earth would anyone contribute to its mitigation? Of course everyone, everyone, contributes to its intensification, no matter how "green" they are. Yes of course, people contribute to the intensification in wildly different degrees.
Trying to solve climate change in anything but a very narrow sense is like trying to perform humane torturing. One can either treat others humanely _or_ torture them. The two at the same time is impossible. The majority of conversations around climate change focus on doing the same things - modernity - but without the negative effects. Chasing a way to humanely torture children will not in fact stop the torturing of children. The goal is wrong! No amount of "solutions" will help you if they all aim to achieve the goal that itself is the root cause of the issues.
Taking Europe as an example, the main strategy is still to use the combination of natural gas, biofuels created from farming corn, and renewables to enable electrification. This strategy lacks both scientific and political consensus among the people who believe in climate change. The result is that as strong one side of the same movement are pushing for it, the other side is also pushing against it. We see the exact same thing with the other major strategies involving tree planting and changes to the culture (diet).
I fear the only solution to this is that a climate correcting perverse incentive materialises, such as fusion at scale being more profitable than fossil fuels, but without mass-panic induced traits such that fission has.
Unless the fake reality starts to crack with the Epstein and other current events and humanity's coming of age will happen. Even if a hundred years later than Bonhoeffer though it would.
We can't cut emissions fast enough politically, but we can race towards economically viable fusion power which would solve the problem from the supply side and would make industrial scale carbon sequestration not insane, for a century or so, until waste heat itself can't be radiated fast enough even in 250 ppm CO2 atmosphere - but that's a problem for the XXII century.
'A "greenhouse Earth" is a period during which no continental glaciers exist anywhere on the planet... Earth has been in a greenhouse state for about 85% of its history.
'Earth is now in an icehouse state, and ice sheets are present in both poles simultaneously... Earth's current icehouse state is known as the Quaternary Ice Age and began approximately 2.58 million years ago.'
https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earthh...
Why? Because candidly looking at those risks as a society means deep collective existential dread, which automatically means an immediate civilizational collapse.
So I'm guessing some of our elite is actually ignorant and the other part is willfully shutting the hell up on this subject to let our civilization run on fumes a few more years.
It's unfortunate because a rapid civilizational collapse could give humanity as a species a better chance of survival.
- https://www.ycombinator.com/blog/rfs-climatetech
- http://carbon.ycombinator.com/
It was a short, short moment of time, but it existed.
If such a thing existed, we could be sure that environmentalists and leftists would have openly embraced it, rather than nip it at the bud 50 years ago. Because they are Good People™. And we should definitely listen to them now because they Follow The Science™.
I always wondered if we just lacked the ability to mobilize to solve big problems anymore but now I look at this 7% US GDP being allocated to AI datacentres and I realize that it isn't a lack of ability, it's a lack of desire.
Imagine if we had ram shortages because all the silicon was being diverted towards making solar panels. Imagine if we had copper shortages because it was going to the windings on wind mills. Imagine if all these economic disruptions were just temporary and for a better cause or eliminating carbon emissions and eventually moving to sequestration of carbon.
Instead we get chatbots. And funny picture makers.
AGI is here
Not realizing we’re gonna go extinct here in the next thousand years unless something solves it
Since humans are incapable of doing this there’s only one possible option: To create something smarter than us and give it the power to solve it because we cannot
don't worry
AI will cause both losing your job AND climate change
When this always-revise-in-one-direction phenomenon happened with the electron charge, it was considered a priori "proof" that scientists were fudging their data to match expectations. The Millikan Oil Drop Experiment is still studied in fundamentals of science class.[0]
If climate scientists are constantly revising their predictions upward, then this is equally "proof" that climate scientists are under pressure to revise their estimates downward. Far from being "alarmist," such terms are actually cudgels used to discourage climate scientists from making their data look too bad.
The result is the predictable fudging of climate data to look better than it really is.
[0] https://en.wikipedia.org/wiki/Oil_drop_experiment#Millikan's...