– Jim Hansen, 23rd June 1988, Senate Testimony
The first transient climate projections using GCMs are 30 years old this year, and they have stood up remarkably well.
We’ve looked at the skill in the Hansen et al (1988) (pdf) simulations before (back in 2008), and we said at the time that the simulations were skillful and that differences from observations would be clearer with a decade or two’s more data. Well, another decade has passed!
James Hansen wishes he wasn't so right about global warming
Michael E. Mann posted this on his facebook page:
More on the models:
Climate scientist Zeke Hausfather's twitter stream confirms the accuracy of Hansens models:
BONUS
THE SMEAR ATTACKS ON JAMES HANSEN
The James Hansen "failed" prediction urban myth debunked:
The James Hansen "failed" prediction urban myth debunked:
The myth: In 1988, Hansen predicted dire warming over the next decade — and he was off by 300%. Why in the world should we listen to the same doom and gloom from him today? In 1988, James Hansen projected future warming trends. He used 3 different scenarios, identified as A, B, and C. Each represented different levels of greenhouse gas emissions. Scenario A assumed greenhouse gas emissions would continue to accelerate. Scenario B assumed a slowing and eventually constant rate of growth. Scenario C assumed a rapid decline in greenhouse gas emissions around the year 2000. The actual greenhouse gas emissions since 1988 have been closest to Scenario B. As shown below, the actual warming has been less than Scenario B. In short, the main reason Hansen's 1988 warming projections were too high is that he used a climate model with a high climate sensitivity. His results are actually evidence that the true climate sensitivity parameter is within the range accepted by the IPCC.
A brilliant debunk of James Hansens "failed" prediction.
Misrepresentations and lies
Undoubtedly there will be claims this week that Scenario A was the most accurate projection of the forcings [Narrator: It was not]. Or they will show only the CO2 projection (and ignore the other factors). Similarly, someone will claim that the projections have been “falsified” because the temperature trends in Scenario B are statistically distinguishable from those in the real world. But this sleight of hand is trying to conflate a very specific set of hypotheses (the forcings combined with the model used) which no-one expects (or expected) to perfectly match reality, with the much more robust and valid prediction that the trajectory of greenhouse gases would lead to substantive warming by now – as indeed it has.
ANOTHER DEBUNK:
While in some instances it is ignorant repetition of misinformation, at its source this story is a plain lie.
In 1988, James Hansen testified before the U.S. Senate on the danger of anthropogenic global warming. During that testimony he presented a graph — part of a paper published soon after. This graph had three lines on it, representing three scenarios based on three projections of future emissions and volcanism. Hansen was right on the money, and the models he used proved successful. Unfortunately, when Patrick Michaels made his testimony before Congress in 1998, ten years later, he saw fit to erase the two lower lines, B and C, and show the Senators only Line A. He did so to make his testimony that Hansen’s predictions had been off by 300% believable. He lied by omission. This lie was picked up by Michael Crichton in his novel State of Fear (one of many omissions, confusions, and falsehood in that book — see here).
Michaels er tilknyttet tankesmien Cato Institute, som er en velkjent spreder av klimaløgner på vegne av olje/kull-industrien. I denne videoen anslår Michaels at han er 40% sponset av dem:
BONUS 2
Hansen predicted the West Side Highway would be underwater MYTH DEBUNKED
James Hansen did not predict in 1988 that "the west side highway would be underwater in 20 years".
HANSEN WAS MISQUOTED
Let's clarify:
"When I interviewed James Hansen I asked him to speculate on what the view outside his office window could look like in 40 years with doubled CO2. I had been trying to think of a way to discuss the greenhouse effect in a way that would make sense to average readers. I was not asking for hard scientific studies. "It was not a academic interview." It was a discussion with a kind and thoughtful man who answered the question. "
OK, so Hansen was asked to speculate what could happen to New York in 40 years, IF there was a doubling in the Co2 level. In an informal setting in conversation with an author.
HERE IS THE THING:
The book The Coming Storm and the Salon article that was printed later are different. In The Coming Storm, the question includes the terms; doubled CO2 and 40 years, while the Salon article, which is the one referred to by skeptics, does not mention the conditions; doubling of C02, and also says 20 years, not the correct 40 years.
To understand the discrepancy between these two published articles, it helps to look at the timeline of the events. The original conversation was in 1988. Ten years later, referring to his notes, Bob Reiss tells about the conversation in his book The Coming Storm. James Hansen confirmed the conversation and said he would not change anything he said. After the book was published, Bob Reiss spoke to a journalist at Salon article. Then he said:
"although the book text is correct, in remembering our original conversation, during a casual phone interview with a Salon magazine reporter in 2001 I was off in years.”
When journalist Bob Reiss retold the story, he made a mistake. Again, THE CONDITIONS WAS; 40 YEARS AND IF IT WAS a doubling IN C02. Check this yourself in Bob Reiss's book The Coming Storm.
We can check back in 2028, at the 40th anniversary, and also when and if we reach 560 ppm CO2 (a doubling from pre-industrial levels). Meanwhile, we can stop using this conversation from 1988 as a reason to be skeptical of the human origin of global warming.
ANYWAY, WEST HiGHWAY was UNDER WATER IN 2012:
____________________________________________________________
James Hansen spådde ikke i 1988, at "the west side highway ville være under vann om 20 år".
Dette er en blank løgn. La oss oppklare:
James Hansen sin uttalelse var svar på et spørsmål fra journalist og forfatter Bob Reiss. Han spår ikke at West Side Highway ville være under vann om 20 år. Bob Reiss rapporterer samtalen som følger, og dette står svart på hvitt i boken hans The Coming Storm.
"When I interviewed James Hansen I asked him to speculate on what the view outside his office window could look like in 40 years with doubled CO2. I'd been trying to think of a way to discuss the greenhouse effect in a way that would make sense to average readers. I wasn't asking for hard scientific studies. It wasn't an academic interview. It was a discussion with a kind and thoughtful man who answered the question."
Hansen ble altså bare spurt om å SPEKULERE i hva som kunne skje med New York om 40 år HVIS det ble en dobbling i Co2 nivå. I en uformell setting i samtale med en forfatter.Boken The Coming Storm og salon.com-artikkelen som ble trykket senere, er forskjellige. I The Coming Storm inkluderer spørsmålet betingelsene; doblet CO2 og 40 år, mens salon.com-artikkelen, som er selvsagt den det blir referert fra av skeptikere, ikke nevner betingelsene om doblet CO2, og dessuten involverer bare 20 år, ikke det riktige, 40 år. For å forstå uoverensstemmelsen mellom disse to publiserte artiklene, hjelper det å se på tidslinjen for hendelsene. Den opprinnelige samtalen var i 1988. Ti år senere, under henvisning til sine notater, forteller Bob Reiss om samtalen i sin bok The Coming Storm. James Hansen bekreftet samtalen og sa at han ikke ville endre noe han sa. Etter at boka ble publisert, snakket Bob Reiss til en journalist på salon.com om samtalen. Da sa han: "although the book text is correct, in remembering our original conversation, during a casual phone interview with a Salon magazine reporter in 2001 I was off in years.” DET ER ALTSÅ FORFATTER OG JOURNALISTEN BOB REISS, SOM INTERVJUET JAMES HANSEN, SOM HAR FORKLUDRET FAKTAENE. BETINGELSENE VAR ALTSÅ 40 ÅR OG HVIS DET BLE EN DOBBLING I C02. Sjekk dette selv i Bob Reiss bok The Coming Storm. Vi kan sjekke tilbake i 2028, på 40-års-markeringen, og også når og hvis vi når 560 ppm CO2 (en fordobling fra preindustrielle nivåer). I mellomtiden kan vi slutte å bruke denne samtalen fra 1988 som en grunn til å være skeptisk til den menneskelige opprinnelsen til global oppvarming. For ordens skyld: East Highway VAR under vann i 2012:
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