Environ. Res. Lett. 2 (April-June 2007) 024002
doi:10.1088/1748-9326/2/2/024002
Scientific reticence and sea level rise
J E Hansen
NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025, USA
Email: [email protected]
Under BAU forcing in the 21st century, the sea level rise surely will be dominated by a third term: (3) ice sheet disintegration. This third term was small until the past few years, but it is has at least doubled in the past decade and is now close to 1 mm/year, based on the gravity satellite measurements discussed above. As a quantitative example, let us say that the ice sheet contribution is 1 cm for the decade 2005–15 and that it doubles each decade until the West Antarctic ice sheet is largely depleted. That time constant yields a sea level rise of the order of 5 m this century. Of course I cannot prove that my choice of a ten-year doubling time for nonlinear response is accurate, but I am confident that it provides a far better estimate than a linear response for the ice sheet component of sea level rise under BAU forcing.
STEVE,
Please read what you post. this is not a prediction or a forecast, it is a hypothetical, unscientific and unrigorous scenario that he contends is possible. it is very extreme and is alarmist, but he VERY clearly says that he has no proof, but only conjectures his confidence that it is more accurate than a linear increase in sea level. While I don’t think this estimate is at all likely his point is quite valid.
It was reported by hundreds of news outlets as a prediction, which was exactly the desired effect.
You guys can’t have it both ways.
It is -70C in the Antarctic interior. How is that meltdown coming along?
How many times are you going to try and say that its too cold in Antarctica for there to be a “meltdown”. No one EVER said that Antarctica would be losing ice through ACTUALLY melting away but rather through dynamical ice discharges changes. You repeat this argument over and over but you don’t have a clue.
Someone doesn’t have a clue. That is for sure.
Robert: are you trying to compete with TonyD?
You managed to get every thing you said wrong.
It is as if you are not even familiar with what is happening at the south pole jut like the alarmist team.
We have researchers down there that are fabricating reports when reality shows a different scenario from what is being reported to promote alarm and the need for further research. You have been listening to fairy tales about glaciers and Antarctica.
Antarctica would be losing ice through ACTUALLY melting away but rather through dynamical ice discharges changes.
Be interesting to see ice jump off land into water.
TonyD:
Of course it is not a scientific forecast because Hansen quit being a scientist over 20 years ago. If his BAU from this paper is anything like his BAU in 1988 it was falsified even before it was published.
Does this mean you agree there is no scientific evidence to support ACC because no predictions were made? Just WAGs. How far do you need to move the goal posts to fit your agenda this time?
Find us a prediction that will prove ACC is a real thing and not your fantasy nightmare you want to share with the world. Maybe you should call a meeting of the team to decide what the consensus is today because you seem to be drifting apart.
you are assuming that is the desired effect. I actually read what he said.
I am not having it both ways.
You on the other hand are distorting what he said for your desired effect.
Why not make a post showing how the media is distorting what Hansen said? I would happily agree with you forcefully if you did that!
You’ve got to be kidding. Hansen is not an idiot, and he knows exactly how to get the press to create global warming panic. He is a master at it.
Yes and that is why he received a gift from the Heinz Foundation.
Tony Duncan
So I was just to your web site and I see you are a comedian. Now I understand where you’re coming from.
Tony,
You are naively assuming that Hansen did not want the headlines he received. He has been playing the media for a long time.
no I am not kidding.
Clearly he believes the IPCC to be wrong in ignoring Greenland and Antarctic ice melt.
I don’t say he is not trying to get publicity, but you wrote that he forecasted 5 meter sea level rise, when he very clearly did not.
He believes, with good reason, that hardly anything is being done about a problem he considers potentially catastrophic. His scenario is not impossible as far as I know. He is entitled to illustrate the most extreme plausible scenario. I don’t agree with it, but he is not saying this is backed by any science, it is just something that is conceivable.
He very clearly did forecast five metres. All forecasts have confidence intervals.
and his confidence interval is miniscule. he clearly says there is no scientific basis for his scenario.
His ONLY confidence is that his extreme scenario is more likely than the IPCC scenarios. THAT you can state as a real prediction. if IPCC scenarios turn out to be right, there is no way Hansen can do anything but say he was wrong. He SAID this specifically to point out that he thinks their predictions are seriously flawed, and he gives good reason for that.
They are all flawed. Rise rates are low and declining.
A plausible scenario would also a cooling of 4C by 2100 globally due to the natural cycles that are coming due and the overall ling term reduction in global temperature leading to the next glacial maximum.
That would lead to more water being locked up in ice year round and a lowering of sea levels.
Of course I will take into account the geothermal activity in the polar regions that has been affecting the glaciers in those regions so even though land ice will increase sea ice should slightly increase or remain steady.
and you would have every right to make that assertion.
Although i would want to see a historical precedent where there was a 4° cooling in a hundred years bought on by natural cycles.
Since the CO2 increase is so dramatic and so quick, Hansen can get away with an extreme scenario, whereas you really cannot. But you have every right to make your claim.
I guess you missed the Younger Dryas period during the transition from maximum glaciation to Holocene Optimum.
There was a global cooling of 4° in less than 100 years?
I have never heard that regarding YD. I will have to check it out. If you are correct, I apologize. In which case your claim would be potentially equally valid.
TonyD:
You have been trained well because you are interpreting it the same way Romm or Tamino would interpret what was sad. It is not the words said but how you felt it was supposed to be interpreted.
You fit right in to the Joseph Goebbles school of truth. Almost as if you were a student of that practice.
This is a good site for you to post at because it allows others to see how facts need to be adjusted to fit the agenda of the ACC cult!
Mike,
you keep missing my relevant posts. as I have stated there is a thing called the IPCC and they make predictions based on the theory. I am pretty sure if you look hard enough on the internet you will find some reference to it.
As I wrote earlier today, just to remind you. the REASON you can’t accept ACC is BECAUSE it has predictions. Remember? You don’t LIKE the predictions.
Steve actually just posted something that he wants to believe undermines those predictions. Talk to Steve. he will tell you to look at past posts where he debunks every single one of the predictions over and over again.
They make lots of predictions and they are all crap.
Tony Duncan says:
November 15, 2010 at 4:13 am
Steve actually just posted something that he wants to believe undermines those predictions.
You aren’t very bright Tony, though you talk like you’re the smartest guy in the room. If they weren’t predictions there is no reason to say them.
TonyD:
You are misinformed because the IPCC does not make predictions and is not a scientific body. The IPCC compiles research done by others and summarizes it. The original researchers and modeling teams create future scenarios of possible futures and the lead authors pick the ones they want to represent the desired result. You have yet to provide a verifiable prediction. Also you missed why there is no theory behind ACC.
When you learn what you are trying to tal about come back with real facts to talk about your BS is to obvious.
I Have not missed any if your irrelevant posts and I find the only thing you have to add is a touch of fantasy that you believe is true. I just do not answer all your BS.
Mike,
I must say I am hurt. I thought we had a special bond.
But you are right. the predictions are in the IPCC report, the IPCC doesn’t make their own.
However if you read the report, you will see numerous verifiable predictions. Even Steve agrees. he says they are all crap.
You keep saying there is no theory behind ACC. But making bizarre statements repeatedly is not going to create that reality.
Why don’t we compromise and say ACC is LIKE a theory. It has all the pieces of a theory, including verifiable predictions. If sea levels do not rise by 10 or 20 centimeters int he next 20 year. If temps don’t increase decadally over the next 20-30 years. If the arctic doesn’t continue to recede during the summer to near ice free conditions by mid century, and a host of other predictions, and at the same time CO2 keeps increasing in the atmosphere, then the “like a theory” will be shown to have sever faults and either be wrong or be missing important factors. I consider both those to be real possibilities, just not very likely. Just as I consider 5 meter sea level rise to be a possibility, but not very likely.
And I have no problem answering almost all of your BS. I guess you don’t like me as much as I like you
It is thermodynamically impossible to melt that much ice over the next 90 years – with the amount of solar energy available in the polar regions. Hansen has absolutely no idea what he is talking about.
TonyD:
The reason that the so called predictions made by the contributors to the IPCC report are junk is because they could also happen under natural weather conditions and not just ACC.
Without a special identifier for ACC there is no ACC! It is simple!
I have a different definition f predictions but modelers that have their results part of the IPCC report scolded me for saying what they contributed to the IPCC was Predictions. I have been trying to follow their definition of what they produce when discussing Climatology.
I would agree with Steven about their predictions however with personal communications from some of the top modelers claiming no predictions were made, I have to take the position that Climatology is not based on science but Pathological science.
With a scientific theory being based on a testable Hypothesis and the WAGs provided to support ACC are not testable or when tested they fail. ACC is not based on a scientific theory. It is that simple! I did read the report and as Steven says the se called prediction are crap and not in any way verifiable as a “Fingerprint” for ACC.
OK I will compromise and say that ACC is like a pathological theory! It actually fits better into the fairy tale category!
When it doesn’t happen he’ll say he never predicted it. And people like Tony Duncan will agree and say anyone who thought it was a prediction wasn’t smart enough to understand.
And both Hansen and Tony Duncan will have been right. because it ISN’T a prediction and those that think it is aren’t smart enough to know how to read English.
What is funny is that if that 5 meters DOES happen it STILL won’t be a prediction.
stevengoddard says:
November 15, 2010 at 3:52 am
You’ve got to be kidding.
He’s a comedian, so it follows he’s here doing comedy.
I have once before objected strenuously to being called a comedian. I have met comedians, I have worked with Comedians, I tony Duncan, am NO comedian.
And Amino Acid. I think I have responded to your other comments in the previous comments.
Oh heck.
Yes there IS a reason to say them if they are not predictions. Read my comments ( i need to get a macro for that sentence).
He says this to show how inadequate he believes IPCC predictions are. That 15 meters is more plausible than 39cm. It is a comparison of extreme possibilities.
Saying 15 meters is more plausible than 39 cm is a prediction or a wild a## guess that he is just pulling out if his posterior. Making a statement about future probabilities is making a prediction.
Mike so you agree, that it is not a prediction.
and while he did not put it that way, you are more or less right that he just pulled it out of his posterior, which is pretty much what he actually said.
Like most everything else in climate science
Steven:
That is the point I am trying to get across! 😉
You misunderstand what you read. TonyD is an ENTERTAINER so he is proficient in contorting what suits his desire to entertain with flights of fantasy. To be a good Entertainer you need to live in your fantasy world to get into the part you are playing. Tony is playing a Climatologist so he needs to adjust facts to suit the agenda like real climatologists.
Close Mike,
I am an entertainer so I reframe the truth in ways that allow people to see reality in a different way. I exaggerate foolish things in the real world, so that people can laugh and then realize that the thing I am making fun of is rather ridiculous after all.
I am not playing a climatologist, just someone who is interested in how people, who are also not climatologists, can so blatantly dismiss what real climatologists have spent 30 years studying. and at the same time arrogantly contend that they are too smart to be fooled by them.
Real climatologists?
The entire “science” is based around computer models of which only a small handful of people are very familiar with the inner workings. The rest is all hearsay, group think and cognitive dissonance.
in which case reality will prove all their predictions wrong.
TonyD:
Reality has already proved all their predictions wrong! That is why they stated years ago they do not make predictions they just provide possible scenarios. Why wait for them to admit it because like in the past they will adjust and claim it is consistent with!
It is also a range of scenarios that include error bars that are larger than any possible outcome. if the temperature goes up it is consistent. If the temperature goes down it is consistent. Of you test 20 years 30 years are needed to show they are wrong. If you wait 40 years you need to wait 60 years and even then they will have a better understanding within the next few years.
It is equal to pulling Numbers out of their posterior!
Tony Duncan says:
November 15, 2010 at 5:22 am
in which case reality will prove all their predictions wrong.
It already has. So why are you still believing them?
Tony Duncan,
I exaggerate foolish things
Yep, you do.
You do comedy, and song and dance too I see.
Tony Duncan says:
November 15, 2010 at 5:17 am
There was a global cooling of 4° in less than 100 years?
I have never heard that regarding YD.
Tony, what you are finding is that there are people who actually know what they are talking about. And you are finding that you do not. I find this is typical of global warming believers.
A 15F drop in 40 years and a 15F rise in 40 years happened during the Younger Dryas.
http://www.youtube.com/watch?v=wo3ovdBt7wY
Tony Duncan says:
November 15, 2010 at 4:37 am
I have once before objected strenuously to being called a comedian
Then you better take the word comedy off the top of your web site, shdnt ya?
If the word comedian was on my website I would take it off!
That’s funny!
You still have you’re day job I hope.
Learning any science here Tony?
I just checked my entire site. You had me worried, but still not one instance of the word comedian.
Well I see that Mike posted a video of Don Easterbrook that says the YD had global temp changes of up to 15° in 40 years. Seeing the source I will have to confirm from other sources. if he is indeed correct, i will finally have learned one piece of information from someone here.
Although I have learned quite a few things from other websites checking out claims from this site that turned out to be ridiculous.
I am certainly much more impressed with Hansen after reading his ’98 paper.
Steve says;
“They are all flawed. Rise rates are low and declining.”
Which is it? Low or declining?
Suppose I said it this way :. “you are thinking slowly and getting even slower”
So you are not really not claiming it is declining at all, just not rising as fast?
The *rate* is declining. i.e. the second derivative is negative.
Can I assume that this declining rate is measured over a suitably short time period to show just that?
If sea level was rising at 5 metres per century, it obviously would not be declining since December, 2009.
As I suspected but even more so. I had expected you to refer to several years of data not less than one.
Why is it obvious? What about natural variation to account for you less than a year? Does any research suggest it must be linear? Do it even say it will rise at a rate of 5m per century? I think you are confusing it with the possibility that it COULD rise by 5m BY the end of the century.
5 meters in 90 years is a rate of 55 mm / year. Obviously that exceeds inter-annual variability
So where does any research say it will rise at 55mm a year, every year?
Sorry, I forgot. It is going to go along really slow now and then increase at a rate of 500 mm per year later on. This will happen after aliens start zapping the ice sheets with giant laser beams.
“This will happen after aliens start zapping the ice sheets with giant laser beams.”
Or they start to melt more rapidly due to rising temperatures.
However I do think my scenario has more support in the scientific literature than your aliens.
The latent heat of melting is much too large to melt that much ice that quickly by earth processes. It would require aliens.
Steve,
if you are right and there is no way that any realistic combination of rising temperatures and low albedo, or other effects could lead to that degree of sea rise, I absolutely agree that he should be thoroughly castigated for making such a statement.
What I said on the Romm 2 meters thread goes here as well. Also, trying to change the definition of the word ‘prediction’ doesn’t help AGWer’s either. You aren’t gonna promote AGW very well by saying, “Uh when someone, uh says they believe something is going to occur in the future… it’s uh, not a uh, predition.” You really must step away from your belief of what you think drives climate for a moment and look at the real, well, no other way to put it, stupidities of your defenses of Hansen and Romm. I couldn’t believe what I was reading. You guys are just flailing now. It’s sad.
Mike Davis says:
November 15, 2010 at 4:57 am
Robert: …You have been listening to fairy tales about glaciers and Antarctica.
no, he is one of those researchers fabricating them.
Is that where all the Peyote from Texas is going? I read a while back about a shortage of buttons used for religious purposes. Maybe that is what they are doing at the south pole!
People think that the Antarctic ice will “slide off” into the ocean. Antarctica is like a washboard – 10,000 foot mountains with lots of valleys inbetween – nothing sliding here! There is edge ablation, similar to Greenland, but limited to a small coastal zone, while the vast mega square miles of the interior is actually accreting snow and ice (I have some stunning photos showing how much the gain is [taken by friends] down there).
There are lots of meteorological reasons for this – too many to go into here, but there is a net gain of ice volume in Antarctica in recent years, and it is a trend that will continue. When the “Toucan Equations” reverse their trend (& I believe they won’t), then Hansen can begin barking up this rising sea level tree again. At this point it is not going in the way he suggests.
The last post I left was this AM – yet the post indicates 4:48 PM – a time that has yet to occur, at least in this time zone.
So! Don’t rely too much on the timestamp!!!