30 Years of Satellite Data Confirm Predictions from Early Models of Sea Level Rise (tulane.edu) 197
"The ultimate test of climate projections is to compare them with what has played out..." says earth sciences professor Torbjörn Törnqvist, lead author on a new study published in the open-access journal Earth's Future (published by the American Geophysical Union).
But after "decades of observations," he says his researchers "were quite amazed how good those early projections were, especially when you think about how crude the models were back then, compared to what is available now." "For anyone who questions the role of humans in changing our climate, here is some of the best proof that we have understood for decades what is really happening, and that we can make credible projections...."
A new era of monitoring global sea-level change took off when satellites were launched in the early 1990s to measure the height of the ocean surface. This showed that the rate of global sea-level rise since that time has averaged about one eighth of an inch per year. Only more recently, it became possible to detect that the rate of global sea-level rise is accelerating. When NASA researchers demonstrated in October 2024 that the rate has doubled during this 30-year period, the time was right to compare this finding with projections that were made during the mid-1990s, independent of the satellite measurements.
In 1996, the Intergovernmental Panel on Climate Change published an assessment report soon after the satellite-based sea-level measurements had started. It projected that the most likely amount of global sea-level rise over the next 30 years would be almost 8 centimeters (3 inches), remarkably close to the 9 centimeters that has occurred.
But it also underestimated the role of melting ice sheets by more than 2 centimeters (about 1 inch). At the time, little was known about the role of warming ocean waters and how that could destabilize marine sectors of the Antarctic Ice Sheet from below. Ice flow from the Greenland Ice Sheet into the ocean has also been faster than foreseen.
"The findings provide confidence in model-based climate projections," according to the paper. Again, its two key points:
But after "decades of observations," he says his researchers "were quite amazed how good those early projections were, especially when you think about how crude the models were back then, compared to what is available now." "For anyone who questions the role of humans in changing our climate, here is some of the best proof that we have understood for decades what is really happening, and that we can make credible projections...."
A new era of monitoring global sea-level change took off when satellites were launched in the early 1990s to measure the height of the ocean surface. This showed that the rate of global sea-level rise since that time has averaged about one eighth of an inch per year. Only more recently, it became possible to detect that the rate of global sea-level rise is accelerating. When NASA researchers demonstrated in October 2024 that the rate has doubled during this 30-year period, the time was right to compare this finding with projections that were made during the mid-1990s, independent of the satellite measurements.
In 1996, the Intergovernmental Panel on Climate Change published an assessment report soon after the satellite-based sea-level measurements had started. It projected that the most likely amount of global sea-level rise over the next 30 years would be almost 8 centimeters (3 inches), remarkably close to the 9 centimeters that has occurred.
But it also underestimated the role of melting ice sheets by more than 2 centimeters (about 1 inch). At the time, little was known about the role of warming ocean waters and how that could destabilize marine sectors of the Antarctic Ice Sheet from below. Ice flow from the Greenland Ice Sheet into the ocean has also been faster than foreseen.
"The findings provide confidence in model-based climate projections," according to the paper. Again, its two key points:
- The largest disparities between projections and observations were due to underestimated dynamic mass loss of ice sheets
- Comparison of past projections with subsequent observations gives confidence in future climate projections
Thanks to Slashdot reader Mr. Dollar Ton for sharing the news.
There are three types of people (Score:5, Insightful)
1) People who accept climate change is real
2) People who accept climate change is real but promote denial for personal profit
3) People who listen to group 2.
Until we do something about group 2, we'll never make any real headway on reducing the root issue.
Re:There are three types of people (Score:4, Insightful)
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This is just a different version of #3 because the last admin passed the largest climate bill in US history.
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That's just a subset of #1 that's aware of #2.
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Is that these scientists? Are these scientists lying about the facts or not?
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Well fuck you too I guess you big baby, it's all a big joke and a troll then why even bother saying anything?
You know you don't have to have an opinion on climate change if you don't actually want to look into it and apply your brain to information.
Re: (Score:2)
Ok, so we're just going with the Mac "Science is a liar, sometimes"
See that's fine. Now I know you're just not a person to be taken seriously or whos opinions we need to give consideration. I get it, thinking is emasculating.
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As much it's about you wanting to feel self-important because you're rejecting the consensus.
At least we acknowledge there is in fact a consensus.
Now all you have to show is why all of them are wrong and/or the global all consuming conspiracy they are engaged in.
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How do I know your science is not as emotionally based on sacred principles that will one day be turned on their heads, as geology was?
You don't. That doesn't change the fact that whatever the current state of science is that's our best understanding of the universe and how it works right now.
Re: There are three types of people (Score:2)
So, in ancient Greece, the sun orbited the Earth despite Aristarchus's heliocentric theory, and in Wegener's day continents did not drift?
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No but believe things even less grounded in reason werent more true because of that.
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typo, -"believe"
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or how about the people who point at individuals not living their entire lives around solving global warming as if that's proof that we aren't altering the composition of our atmosphere so that it contains more heat retaining elements.
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People who think climate change won't be in their backyard.
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Do the numbers match the RCP 8.5 projection? Do they vindicate Dr Mann's projections?
Re: There are three types of people (Score:4, Informative)
Re: (Score:2, Informative)
Evangelicals Christians are huge Trump supporters. For their support (worshi
To Serve Man (Score:3)
#7 is I am an alien that is working to terraform Earth for my species. It is a subset of #3, but we intend on feasting on #2 and #3
Re:There are three types of people (Score:4, Insightful)
Unfortunately, group 1 is far smaller than group 2+3. And that is why humanity does not have much chances for a long-term future.
Voting rights (Score:2)
The problem is that the margin between sensible people and idiots isn't really that huge. I don't know for sure about the rest of the world but here in America about 47% of the country will fall for propaganda.
That means all anyone has to do to stymie
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'real headway on reducing the root issue.'
Since you reference reducing the root issue ( prefer resolving, but hey), I assume you subscribe to the The Adams Law of Slow Moving Disasters... (now most often named slow-onset disasters).
Good for you. I suspect however that this is not helpful to the climate grifters who intend to profit from all this.
You left out the people who reject the theories of climate disaster (ought we term it 'anthropomorphic climate degradation' and agree we just don't like the change
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I personally don't trust the data, because I don't trust the proponents.
To be clear, which data do you not trust specifically? For example, do you doubt sea level rise data and, if so, why? Basically, can you map out which parts of the data you deny and which parts you think are real? Because there are a lot of different data points pointing to the Earth warming, climate changing, sea level rising, etc. Are you just blanket saying that absolutely none of it is happening, or are there specific things that you think really are happening and other things that you think are not? If
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No one is saying it will kill us all tomorrow. The grief you hear is for future generations and the critters in the environment.....you know, the ones that hold our kids, the critters, grand-kids, the grand-critters, etc. Get yer mind off your own sorry ass.
Re: There are three types of people (Score:2, Interesting)
What if we used the techniques critters have used to adapt to climate change in the past, i.e. free migration (open the borders and, since we have made money an essential resource in our social world, a strong basic income)?
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You're just giving the right wing another reason to pretend climate change isn't a thing...
Re: There are three types of people (Score:2)
Does it threaten your human urge to control and manage everything?
Re: There are three types of people (Score:2)
How about just give them money and let each individual decide for themselves how they want to deal or not deal with climate change?
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No one is saying it will kill us all tomorrow. The grief you hear is for future generations and the critters in the environment.....you know, the ones that hold our kids, the critters, grand-kids, the grand-critters, etc. Get yer mind off your own sorry ass.
Future generations are quite capable of fucking things up even faster than previous generations and it is pretty obvious they are quite intent on doing so. I have no interest in the world they want, so I'm just going to enjoy my life while I can in spite of them and then they can do whatever they want when I'm not here.
Re: There are three types of people (Score:2)
yeah keep telling yourself that.
Its a variation on the old argument leveled at environmental activists since the 50s at least. They got rid of DDT and you can swim in a lot of open water again, thanks to them.
Making your own life hell if nobody else does is a quick way to failure. And those that argue for it, belong in group 2 or 3.
We need to scale down industrial and private fossil fuel use, but if only activists give up modern life, they won't make an impact.
We're talking about a reduction in co2 emission
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Cities are more efficient than living in the middle of nowhere, and people who live outside cities use more fossil fuel than people who live in them. And properly managed cities do not have air full of toxins, and there's nothing about cities that means the water would have them.
Also the phrase "virtue signalling" just means "Someone says they care about something, I don't care about anything, therefore I will pretend or even believe that person I'm replying is lying." It literally means the speaker is a ps [wikipedia.org]
Re: There are three types of people (Score:5, Informative)
Global warming is already resulting in "38 trillion dollars in damages each year".
https://www.sciencedaily.com/r... [sciencedaily.com]
"5 million deaths a year to abnormal temperatures"
https://www.monash.edu/news/ar... [monash.edu]
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More like, it's not all fake, but it's also not gonna kill us all tomorrow (or ever) and the guy telling me it is is a grifter selling tickets to heaven to gullible people.
I see the TEOTWAWKI mods have been through. They exemplify your comments and are too dumb to know it. Go figure.
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>>let billions starve because evil carbon bad
Can we assume you are type #5? If so, utter bullshit.
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Billions will starve if we don't stop burning fossil fuels.
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Your mind powers will not work on me, boy.
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This is just #3 with extra steps
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Ok, if the sea levels ARE rising, then why did "one of the worlds smartest presidents" (as people said),
Barack Obama, build a huge mansion on MARTHA'S VINEYARD, which is a small island?
One guy I don't like did a hypocritical thing I don't like, so the world can burn I guess?
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He didn't?
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For starters, how would Obama building a home even below sea level disprove global warming? Even if Obama announced tomorrow that global warming was a hoax, how would that disprove global warming?
Basically, why do you think Obama is God where his choices shape reality?
After that said property is very likely high enough to where flooding won't be a problem until after he's dead. While elevation numbers aren't available for the home aerial shots are and the home looks well above sea level.
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Obama is a well-off boomer (pretty much right by the cutoff in age) whose house is ten feet above sea level and not directly above see level. It will be about 11 years until Obama reaches the average age of death for males born when he was born (or born currently since it went up, but then went back down again). It will be about 15 years until he reaches the age of the current president. It will be about 23 years until he reaches the average age of death for wealthy males in the US. For those numbers respec
Why not mention plate tectonics? (Score:2)
"The essential point: Sea level rise isnâ(TM)t just about the sea; itâ(TM)s also about the land. Various forces cause terra firma to sink or rise on its own, in a process called vertical land movement (VLM). In some Eastern states, settling sediments and groundwater extraction are making coastal lands subside, adding an estimated 1.3 to 1.9 millimeters a year to relative sea level rise on Marylandâ(TM)s coast and .84 millimeters at Boston .
Washingtonâ(TM)s story is very different. [...]
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Re: Why not mention plate tectonics? (Score:2)
Did they know plate tectonics affected sea level drop (in the PNW) at all in the 1970s? Wasn't the theory then rebound from the ice age? So if they used flawed models of local sea levels in thd 1970s models, is it just luck their predictions agree with observation?
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Re: Why not mention plate tectonics? (Score:2)
What if it's noise? Remember how the earth was predicted to slow down, but now its spin is speeding up?
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What if it's noise?
We have statistical methods to distinguish noise from data.
Remember how the earth was predicted to slow down, but now its spin is speeding up?
Sigh. And do you remember what they say about the mating habits of spotted owls? Also, Earth is predicted to slow down on average, but can experience temporary glitches as the inner masses rearrange slightly.
Re: Why not mention plate tectonics? (Score:2)
How emotionally attached are you (sighing so dramatically!) to the idea that a few observations match your sacred theory?
Why not acknowledge that data is noisy and cyclical and trends depend upon a lot of assumptions that make margins of error very wide, too wide to justify hasty, well-meaning, unintended-consequences-producing regulation?
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How emotionally attached are you (sighing so dramatically!) to the idea that a few observations match your sacred theory?
Are you an LLM?
Why not acknowledge that data is noisy and cyclical and trends depend upon a lot of assumptions that make margins of error very wide, too wide to justify hasty, well-meaning, unintended-consequences-producing regulation?
So let me rehash this: you found one unrelated fact from a completely separate field of study, quoted it wrongly, and then used that to imply that concern about global warming is merely "emotional attachment"? Yep, totally matches the behavior of dirtbag scammer trash.
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Why not acknowledge that data is noisy and cyclical and trends depend upon a lot of assumptions that make margins of error very wide, too wide to justify hasty, well-meaning, unintended-consequences-producing regulation?
Jebus, Slashdot used to be filled with nerds, especially computer nerds. Where did all of you people come from. Anyone who has ever had to deal with interpreting any sort of signal 100% recognizes noise and recurring artifacts, etc. acknowledges them. They also, however, recognize that a noisy signal is still a signal and there are many viable techniques to clean that up and get a useful signal. I mean, for a lot of traditional nerds, this stuff is their bread and butter.
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What if it's noise? Remember how the earth was predicted to slow down, but now its spin is speeding up?
The Earth's spin is definitely slowing down. This is a long term trend on geological scale that is well understood and is based on tidal interactions with the moon. Basically the tidal bulge that the moon creates on Earth shifts the center of gravity of Earth in a way that pulls the moon in its orbit, accelerating it. That leads to energy from the Earth's rotation being shifted to the orbit of the moon in the Earth-Moon system. End result, moon gets further away, Earth's spin slows. That's on a long scale,
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To your point, though, isostatic rebound has long been known and accounted for in local histories of shorelines. Plate tectonics do not, however, affect sea level appreciably.
Re: Why not mention plate tectonics? (Score:2)
Can you prove you're not hallucinating? Or are we supposed to trust your confident-sounding tone, as we're supposed to trust all con-men?
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And if you're looking at these kinds of timelines, there are also other feedback loops driven by tectonics. Rock weathering, primarily.
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Interestingly, the biggest influence on long-term (100s of millions of years) global climate is the positions of the continents, which plate tectonics are directly responsible for.
Careful. On these discussions you really need a "but" or "however" to make it clear that long-term is not the same as short-term. Possibly pointing out that the amount of continental drift in the period actually under discussion is probably barely above the height of the average person.
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You will cling desperately to anything, any hypothesis, no matter how improbable or ludicrous, in order to refuse to accept what is literally staring you in the face.
Re: Why not mention plate tectonics? (Score:2)
Are you talking about yourself?
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No. If I were, I would use words like smart, intelligent, wise, charming, handsome, etc.
Silly boy.
Re: Why not mention plate tectonics? (Score:2)
Does defending the consensus on climate change make you feel as smart as the geologists who ridiculed Wegener personally?
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Does being a contrarian make you feel important?
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I think I get where Blue Trane is coming from based on their posts across this discussion. Do you remember the Electric Universe proponents who always used to post on Slashdot (they later mostly rebranded themselves as "Plasma Cosmologists" to sound more authentic). Basically, they had some basic understanding of Maxwell's equations and clung to them, essentially insisting that they dominated all physics at all levels. Hence fusion powering stars was a hoax, and stars were actually giant iron spheres and th
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I think someone on the conspiracy podcasts they listen to recently said "ocean level rises aren't real because tectonics" and now they're just repeating it like a parrot.
Oh no! (Score:5, Funny)
This is terrible, depressing news! Thank God the next round of satellites will be designed without the ability to measure such things - I only want to hear good news!
Soothing (Score:2)
Magaode off.
Very soothing coping strategy.,
Obviously (Score:4, Interesting)
The early climate models were pretty good. The measurement data was in part, but in part not. All the deniers are basically a cult now with no connection to reality.
Re: Obviously (Score:2)
Did the early models know about methane leaks from beaver ponds in the northern tundra? Did they include oxygen generation by electrolysis from manganese nodules on the ocean bottom? What if the models are like epicycles, vaguely right for the wrong reasons?
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And what if you are just flinging crap in the hopes some may stick?
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What if the models are like epicycles
Then you should be able to easily disprove them. You have all the data available.
Be a Kepler and come up with a new theory that fits the said data better.
Easy-peasy.
Re: Obviously (Score:2)
How about my ground-based observations of stream levels and tree conditions and such at various campsites I've been frequenting for decades?
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Not relevant and not credible.
Unlike the models above, no credible and verifiable evidence of your observations is presented and no link to the sea levels is demonstrated.
0/10.
Try again.
One foot per century (Score:2)
From the fine article:
This showed that the rate of global sea-level rise since that time has averaged about one eighth of an inch per year.
So this is about one inch per decade, or about one foot per century.
Human civilization can't adjust to a rise of sea level at the rate of one foot per century? I'm pretty sure that large segments of land around the world are already one foot below sea level and are dry, occupied by people, and considered safe from being flooded by the sea. What's the problem again? That coastal cities might be flooded? It appears that already happens with regularity as a matter of storm surges. Th
Re:One foot per century (Score:4, Insightful)
What's the problem again?
It isn't the only problem to "adjust" against.
And the costs, as the massive, unseen hereto forest fires in Eurasia in the past decade have shown, are enormous even for any single problem of the list.
Re: One foot per century (Score:2)
Are those costs why Russia is losing in Ukraine?
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Can you please repeat that in a language you know well, maybe then the point you're trying to make will become apparent?
Sea side cities have been flooded for centuries... (Score:2)
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Why don’t you use the data and run your own simulation to prove everyone wrong?
Re:Don't look at observations, look at my guess! (Score:5, Insightful)
Nice way you have of dismissing science.
You: Doctor, I have this pain in my ass, what's the problem?
Doctor: You have Watusi Ass. It is a serious condition.
You: Doctor, Doctor, can it be cured?
Doctor: Well, the data say that if you take these pills, the condition will clear up....about 90 % of the time. The mathematical modeling is imprecise. They are just guessing about the 90 %. Sure, 90 % of patients do pull out of it, if they take the pills, but you cannot count on the science. I cannot tell whether you are in the other 10 %. So my advice to you is skip the pills, it's just science and they have no idea what they are doing.
Doctor: You could also go to see the Witch Doctor up the road from me. He'll believe anything you want to believe. You'll feel better, guaranteed.
Fuck Rockefeller medicine (Score:2, Funny)
I don't need any of your God damned pills. I don't swim in carcinogenic toxins all day every day like you city rats, and if I did, I damn sure wouldn't be stupid enough to believe the cure is a bunch of Rockefeller's pills. I'm in my 40s, take exactly zero "pills", and will easily outlive you. I will write your obituary, and it won't be kind.
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You do realize how much your writing sounds like complete and total parody, right? If I had not seen enough of your posts on other threads on the discussion, I am pretty sure I would not have realized you were serious. I would have thought you needed to be marked up as funny. I'm not kidding, that is how crazy your post sounds.
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Ok. That pretty much removes you from the running for remotely credible. That was a hypothetical. That is essentially a small universe described for a thought experiment. A scenario was presented where a patient has a serious medical condition and there is obviously a high chance that the described pills will cure it and your response... is to assume that doctors in the hypothetical universe only prescribe pills for profit? Do you realize how nuts that is.
Even in our real world where there are a lot of thin
Re:Don't look at observations, look at my guess! (Score:4, Insightful)
>> it explicitly rejects scientific method. Including in this case, where it rejects observations that contravene the modelling
All you need is some evidence for your bizarre claims.
Re:Don't look at observations, look at my guess! (Score:5, Insightful)
All I read is "This science says things I don't wanna hear therefore it isn't real science".
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Maybe the real science is the friends we make along the way.
Re: You are a cult member. Seek help. (Score:2)
Thus why shouldn't I believe physics is just psychics?
Re: Don't look at observations, look at my guess! (Score:3)
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These people never learn. Your model is a guess.
You never learn. This story is about how their model turned out to be a really great guess and you're still in here with this bullshit.
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AGW discussions always bring out the most boring trolls.
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(Looks in the mirror.)
FTFY.
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Have you figured out the '69 "moon landing" was fake too, dipshit, or is that obvious fact still beyond your ken?
Yeah no shit. Obviously filmed on a sound stage on mars. Don't believe me look at the gravity. Obviously wrong for the earth AND moon. Also why is there air.
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>> Remind me, what's Einstein's definition of insanity?
Happy to, except I don't know it. I suspect you're referring to the quote "the definition of insanity is doing the same thing over and over again and expecting different results" but it turns out that there's no evidence that Einstein ever said that, it's more likely the anonymous writer of a booklet for AA or Rita Mae Brown.
Well, there you go. Turns out checking your facts is something you didn't do when writing your post. These people never lear
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Yep. It's times like these when I refer to another quote attributed (correctly or not) to Einstein:
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.
Re: Oh look anti-science nutter Luckyo is at it ag (Score:2)
What if our numbers grow and we elected a President?
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You'd all be in the ICE AGE they predicted back then
Who is "they" specifically? A big part of the problem with credibility of information these days is that so many people seem to have claims about information they either claim is true or false that "they" told them, but without a clear idea of who "they" are. For example, I believe that sea level is rising. If I were a low-information ranting type (I consider my rants to be relatively high information most of the time) I might, for example, talk about how "they" were claiming that sea-level rise would compl
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I was born in the 50s. Either you're remembering wrong or you were listening to the wrong "everyone".
I remember global warming being discussed as early as the late 60s. (I was too young for any of that earlier)
The Milankovitch cycle theories were getting refined and stories about them and scientific debates about the rate of change approaching glacial maxima periods were popu
Re:exactly! (Score:4, Informative)
I was born in the 50's. I remember everyone in the early-mid 70's saying we were entering another ice age and we were all doomed! Then in the 90's Algore came along with the global warming nonsense. Around 2008/9 the warming came down and they had to rename it "climate change".
Your memory is failing you then because global warming has been a concern since the 70's and global cooling was never much of a thing outside of the news. After that, just because science has been wrong before doesn't make all science wrong. We don't throw everything out we know about physics because Issac Newton thought Mercury would make his brain work better.
Global warming is stupid easy to understand, we're altering the atmosphere to be heavier in parts that we know for a fact retain more heat then the rest.
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Antarctica is gaining ice
No, it's losing ice,
Greenland is gaining ice.
No, it's losing ice
the Arctic is melting far more slowly than expected
No, it's faster.
Floating ice sheets are completely irrelevant to sea level
Indeed, but Greenland and Antartica are losing grounded ice mass. So your comment is as irrelevant as your others are incorrect.
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The Met Office climate prediction model: HadGEM1 climate model has projected Arctic ice loss with reasonable accuracy up to the present day. The model projects that sea ice decline will continue over the 21st Century; however it also shows the possibility of a period of up to 20 years when the ice loss is temporarily slowed. This period is caused by reductions in ice export from north of Greenland, and by a weakening of the North Atlantic overturning circulation (which results in a reduction of warm water transported into the Arctic).
https://nsidc.org/learn/ask-sc... [nsidc.org]
This shows observed ice extent loss in the Arctic towards the bottom of the ensemble lower bound. That is not characteristic of it being slower than expected.