A major error in an alarming study published in Nature

Dec 2013
31,210
18,691
Beware of watermelons
#1
Fredericb/DreamstimeA major error in an alarming study published in Natureon October 31 suggesting that "ocean warming is at the high end of previous estimates, with implications for policy-relevant measurements of the Earth response to climate change, such as climate sensitivity to greenhouse gases and the thermal component of sea-level rise." How much higher? Using a novel technique to measure the accumulation of heat in the oceans, Princeton geoscientist Laure Resplandy and her team calculated that the amount of heat being absorbed by the oceans is more than 60 percent higher per year than the estimates offered by the United Nations' Intergovernmental Panel on Climate Change in 2014.
Dire headlines warning that catastrophic global warming was more likely than previously thought ensued.
However, British climate researcher and statistician Nicholas Lewis re-crunched the numbers in the study and found that Resplandy and her team had made significant errors in their calculations. I noted in my reporting on the controversy that I had reached out to Resplandy and had not heard back from her or her colleagues yet. I added that I expected that she and her colleagues need time for a careful evaluation of Lewis' arguments. Now co-author Scripps Institution of Oceanography climate scientist Ralph Keeling has acknowledged that Lewis is at least partially right and the reseachers are preparing a correction to their original article (apparently not yet published).
The San Diego Union-Tribune article, "Climate contrarian uncovers scientific error, upends major ocean warming study," is reporting that Keeling now accepts that Lewis is right and that the study's findings are far more uncertain than they had claimed in their Nature article. "When we were confronted with his insight it became immediately clear there was an issue there," Keeling said to the Union-Tribune. "We're grateful to have it be pointed out quickly so that we could correct it quickly."
"Our error margins are too big now to really weigh in on the precise amount of warming that's going on in the ocean," Keeling said. "We really muffed the error margins."
But getting the error margins wrong is not the only problem with the research, suggests Lewis. Keeping in mind that the correction has not yet been peer-reviewed or published, Lewis responded to an email asking for his reaction to these developments:
In general terms, if [Keeling] is only saying that they acknowledge that their study underestimated the uncertainty in their ocean heat uptake estimate, that is not enough. They should also acknowledge that another consequence of their mishandling of the treatment of uncertainty was that their central estimate of ocean heat uptake was overstated by approximately 30%.
So far as I can tell (from statements on their websites), the authors hope to alter an assumption that affects one aspect (that relating to constancy of the land oxygen-carbon exchange ratio) of the input data used to derive their ocean heat uptake estimate, in such a way that will increase its level, when correctly calculated, to a value close to their originally published estimate. It would seem a little surprising that a valid adjustment made after publication happened, conveniently, to have the effect of almost cancelling a statistical methods error.
Unfortunately their work involves many assumptions where there scope for subjective choices by the authors, so it is difficult to validate those assumptions. I would hope that Nature will have any changes made by the authors to their assumptions examined carefully by peer reviewers who are experts in the same field as Resplandy and Keeling, as well as by statistically expert peer reviewers. However, the failure of the original peer review and editorial process to pick up the fairly obvious statistical problems in the original paper do not engender confidence in Nature's approach​


Widely Reported Alarming Ocean Warming Study Is Wrong
 
Apr 2013
34,969
23,667
Left coast
#2
Fredericb/DreamstimeA major error in an alarming study published in Natureon October 31 suggesting that "ocean warming is at the high end of previous estimates, with implications for policy-relevant measurements of the Earth response to climate change, such as climate sensitivity to greenhouse gases and the thermal component of sea-level rise." How much higher? Using a novel technique to measure the accumulation of heat in the oceans, Princeton geoscientist Laure Resplandy and her team calculated that the amount of heat being absorbed by the oceans is more than 60 percent higher per year than the estimates offered by the United Nations' Intergovernmental Panel on Climate Change in 2014.
Dire headlines warning that catastrophic global warming was more likely than previously thought ensued.
However, British climate researcher and statistician Nicholas Lewis re-crunched the numbers in the study and found that Resplandy and her team had made significant errors in their calculations. I noted in my reporting on the controversy that I had reached out to Resplandy and had not heard back from her or her colleagues yet. I added that I expected that she and her colleagues need time for a careful evaluation of Lewis' arguments. Now co-author Scripps Institution of Oceanography climate scientist Ralph Keeling has acknowledged that Lewis is at least partially right and the reseachers are preparing a correction to their original article (apparently not yet published).
The San Diego Union-Tribune article, "Climate contrarian uncovers scientific error, upends major ocean warming study," is reporting that Keeling now accepts that Lewis is right and that the study's findings are far more uncertain than they had claimed in their Nature article. "When we were confronted with his insight it became immediately clear there was an issue there," Keeling said to the Union-Tribune. "We're grateful to have it be pointed out quickly so that we could correct it quickly."
"Our error margins are too big now to really weigh in on the precise amount of warming that's going on in the ocean," Keeling said. "We really muffed the error margins."
But getting the error margins wrong is not the only problem with the research, suggests Lewis. Keeping in mind that the correction has not yet been peer-reviewed or published, Lewis responded to an email asking for his reaction to these developments:
In general terms, if [Keeling] is only saying that they acknowledge that their study underestimated the uncertainty in their ocean heat uptake estimate, that is not enough. They should also acknowledge that another consequence of their mishandling of the treatment of uncertainty was that their central estimate of ocean heat uptake was overstated by approximately 30%.​
So far as I can tell (from statements on their websites), the authors hope to alter an assumption that affects one aspect (that relating to constancy of the land oxygen-carbon exchange ratio) of the input data used to derive their ocean heat uptake estimate, in such a way that will increase its level, when correctly calculated, to a value close to their originally published estimate. It would seem a little surprising that a valid adjustment made after publication happened, conveniently, to have the effect of almost cancelling a statistical methods error.​
Unfortunately their work involves many assumptions where there scope for subjective choices by the authors, so it is difficult to validate those assumptions. I would hope that Nature will have any changes made by the authors to their assumptions examined carefully by peer reviewers who are experts in the same field as Resplandy and Keeling, as well as by statistically expert peer reviewers. However, the failure of the original peer review and editorial process to pick up the fairly obvious statistical problems in the original paper do not engender confidence in Nature's approach​


Widely Reported Alarming Ocean Warming Study Is Wrong
Man, can you pick them or what?

Ronald Bailey is an American libertarian science writer. He has written or edited several books on economics, ecology, and biotechnology.Wikipedia
I don't see climate science in any of his CV.
 
Likes: Hollywood
Feb 2007
5,075
2,768
USA
#4
Resplandy et al. correction and response
Filed under: — group @ 14 November 2018

Guest commentary from Ralph Keeling (UCSD)
I, with the other co-authors of Resplandy et al (2018), want to address two problems that came to our attention since publication of our paper in Nature last week. These problems do not invalidate the methodology or the new insights into ocean biogeochemistry on which it is based, but they do influence the mean rate of warming we infer, and more importantly, the uncertainties of that calculation.

We would like to thank Nicholas Lewis for first bringing an apparent anomaly in the trend calculation to our attention. We quickly realized that our calculations incorrectly treated systematic errors in the O2 measurements as if they were random errors in the error propagation. This led to under-reporting of the overall uncertainty and also caused the ocean heat uptake to be shifted high through the application of a weighted least squares fit. In addition, we realized that the uncertainties in the assumption of a constant land O2:C exchange ratio of 1.1 in the calculation of the “atmospheric potential oxygen” (APO) trend had not been propagated through to the final trend.

As the researcher in charge of the O2 measurements, I accept responsibility for these oversights, because it was my role to ensure that details of the measurements were correctly understood and taken up by coauthors.
We have now reworked our calculations and have submitted a correction to the journal.

Details
In our definition ΔAPO, we used a default value of 1.1 for O2:C oxidative ratio (OR) of land carbon. However, a lower ratio is probably more appropriate. Specifically, Randerson et al. (2006) argued for a ratio of around 1.05, based on the composition of stems and wood, given that woody biomass dominates longterm carbon sources and sinks on land. Other recent studies have suggested similar ratios e.g. Clay and Worrall (2015). Our previous calculations did, in fact, allow for a range from 1.05 ± 0.05, consistent with above estimates and typical uncertainty ranges. However, we applied this range only for the ΔAPOClimate to ΔOHC ratio but neglected the impact on the APO budget itself, which used a fixed ratio of 1.1. If the actual OR were lower than 1.1, the observed APO decrease (ΔAPOOBS) would include a contribution from the global land carbon sink, because the ΔO2 term then imperfectly cancels the 1.1 ΔCO2 term.
In the updated calculations we now also allow apply the OR range (1.05 ± 0.05) to the APO calculation which by itself increases the APOClimate trend by 0.15 ± 0.15 per meg/yr relative to an estimate using 1.1.

Bottom Line
We recomputed the ΔAPOClimate trend and its uncertainty based on the distribution of the unweighted least square fits to each of the 106 ensemble realizations of ΔAPOClimate generated by combining all sources of uncertainty, with correlated errors now treated as systematic contributions to the trend. The resulting trend in ΔAPOClimate is 1.05 ± 0.62 per meg/yr (previously 1.16 ± 0.18 per meg/yr) which yields a ΔOHC trend of 1.21 ± 0.72 x 1022 J/yr (previously 1.33 ± 0.20 x 1022J/yr), as summarized in the updated Figure 1:



The revised uncertainties preclude drawing any strong conclusions with respect to climate sensitivity or carbon budgets based on the APO method alone, but they still lend support for the implications of the recent upwards revisions in OHC relative to IPCC AR5 based on hydrographic and Argo measurements.
http://www.realclimate.org/index.php/archives/2018/11/resplandy-et-al-correction-and-response/
 
Dec 2013
31,210
18,691
Beware of watermelons
#5
Man, can you pick them or what?



I don't see climate science in any of his CV.
Yup, there you guys go. One must have a fancy piece of paper to have an opinion worthy consideration.




dogmatic adjective
dog·mat·ic | \dȯg-ˈma-tik, däg-\
variants: or less commonly dogmatical \ -ti-kəl \
Definition of dogmatic
1 : characterized by or given to the expression of opinions very strongly or positively as if they were facts
a dogmatic critic
2 : of or relating to dogma (see DOGMA)



dog·ma
/ˈdôɡmə/Submit
noun
a principle or set of principles laid down by an authority as incontrovertibly true.
"the Christian dogma of the Trinity"
synonyms: teaching, belief, tenet, principle, precept, maxim, article of faith, canon;




re·li·gion
/rəˈlijən/Submit
noun
the belief in and worship of a superhuman controlling power, especially a personal God or gods.
"ideas about the relationship between science and religion"
synonyms: faith, belief, worship, creed; More
a particular system of faith and worship.
plural noun: religions
"the world's great religions"
a pursuit or interest to which someone ascribes supreme importance.
"consumerism is the new religion"
 
Dec 2014
25,114
13,550
Memphis, Tn.
#6
Yup, there you guys go. One must have a fancy piece of paper to have an opinion worthy consideration.




dogmatic adjective
dog·mat·ic | \dȯg-ˈma-tik, däg-\
variants: or less commonly dogmatical \ -ti-kəl \
Definition of dogmatic
1 : characterized by or given to the expression of opinions very strongly or positively as if they were facts
a dogmatic critic
2 : of or relating to dogma (see DOGMA)



dog·ma
/ˈdôɡmə/Submit
noun
a principle or set of principles laid down by an authority as incontrovertibly true.
"the Christian dogma of the Trinity"
synonyms: teaching, belief, tenet, principle, precept, maxim, article of faith, canon;




re·li·gion
/rəˈlijən/Submit
noun
the belief in and worship of a superhuman controlling power, especially a personal God or gods.
"ideas about the relationship between science and religion"
synonyms: faith, belief, worship, creed; More
a particular system of faith and worship.
plural noun: religions
"the world's great religions"
a pursuit or interest to which someone ascribes supreme importance.
"consumerism is the new religion"

Yeah, ain't it just awful? I take the opinion of my doctor, who has one on those fancy pieces of paper called a degree in medicine, over the opinion of the landscapiier when it comes to health issues. Go figure.
 
Likes: RNG

Similar Discussions