Memo to media and deniers: If your “global cooling” piece revolves around Dr. Latif, you probably have the entire story backwards. But, at least for deniers, that is the goal.
In an interview today, Dr. Latif told me “we don’t trust our forecast beyond 2015″ and “it is just as likely you’ll see accelerated warming” after then. Indeed, in his published research, rapid warming is all-but-inevitable over the next two decades. He told me, “you can’t miss the long-term warming trend” in the temperature record, which is “driven by the evolution of greenhouse gases.” Finally, he pointed out “Our work does not allow one to make any inferences about global warming.”
Latif’s work can be baffling, but I mostly deciphered it on this blog in 2008 (see “Nature article on ‘cooling’ confuses media, deniers: Next decade may see rapid warming“). Latif’s Nature study is consistent with the following statements:
- The “coming decade” (2010 to 2020) is poised to be the warmest on record, globally.
- The coming decade is poised to see faster temperature rise than any decade since the authors’ calculations began in 1960.
Here is his Nature “forecast” in green (”Each point represents a ten-year centred mean” — more discussion at the end):
Now, with the caveat that Latif claims no “skill” in any forecast after 2015 — a caveat the media and deniers never print — as you can see, their model suggests we’ll see pretty damn rapid warming in the coming decade, just as the Hadley Center did in a 2007 Science piece and just as the US Naval Research Lab and NASA recently predicted (see “Another major study predicts rapid warming over next few years — nearly 0.3°F by 2014“).
How badly have the media [and deniers] botched this reporting unintentionally [and intentionally]? Let’s see:
Three mistakes in one New Scientist headline from last month — a record, I suspect. The headline would have been more accurate if it said, “World poised to see accelerated warming in the coming decade.”
Then we have these multiply-misleading statements:
… global temperatures have been relatively stable for a decade and may even drop in the next few years….
Dr. Mojib Latif, a prize-winning climate and ocean scientist from the Leibniz Institute of Marine Sciences at the University of Kiel, wrote a paper last year positing that cyclical shifts in the oceans were aligning in a way that could keep the next decade or so relatively cool, even as the heat-trapping gases linked to global warming continue to increase.
Those quotes from Revkin’s recent piece are not what Latif’s paper posited. Revkin’s entire thesis is wrong, as I showed here. Global temperatures have been rising measurably for decades. My extended interview with Latif makes clear just how inappropriate it is to use his work to make the case we are headed into a decade or more of being “relatively cool.” At the very least, we are going to stay relatively hot. But you could just as easily — and more accurately — use his work to make the case that we are headed into a decade or more of rapid warming. He models only “internal fluctuations” around the overall anthropogenic warming trend, so if warming seems to stall for a few years, it must catch up to the long-term trend, sometimes quite rapidly.
[And I just noticed Revkin’s use of the word “linked.” C’mon, status quo media! That would be like saying South Carolina Gov. Mark Sanford was “linked” to an Argentinian woman. They had a torrid affair, and heat-trapping gases cause global warming. That’s why they’re called “heat trapping gases”! But I digress.]
George Will quoted Revkin’s error-riddled piece and then compounded the mistakes with a few outright falsehoods:
In the fifth paragraph, a “few years” became “the next decade or so,” according to Mojib Latif, a German “prize-winning climate and ocean scientist” who campaigns constantly to promote policies combating global warming. Actually, Latif has said he anticipates “maybe even two” decades in which temperatures cool.
No, Latif does not “anticipate” maybe even two decades of cooling. He doesn’t even predict it. Again, as Latif will happily tell anyone who asks, “my only forecast is to 2015.”
The non-existent fact-checkers of the Washington Post could not even be bothered to click on the link they inserted, which doesn’t even contain the phrase “maybe even two”! Will just made up the quote. And the link is to an editorial of Investors Business Daily [IBD] which is roughly equivalent to an editorial in the Wall Street Journal as a source for climate facts.
And then we have the outright lies of the Swift boat smearer. In his never ending quest to destroy both a livable climate and the English language, the uber-disinformer and self-acknoweldged performance artist Marc Morano actually wrote:
Why does Eilperin fail to note that a top UN IPCC scientist, Mojib Latif of Kiel University in Germany told a UN conference earlier this month that he is now predicting global cooling for several
decades and he admitted he was unsure how much the North Atlantic Oscillation (NAO) had impacted global temperatures in the past three decades.
So now Latif is “predicting global cooling for several decades” although the link to that assertion goes to Morano’s own screamingly inaccurate headline:
UN Fears (More) Global Cooling Commeth! IPCC Scientist Warns UN: We are about to enter ‘one or even 2 decades during which temps cool’
For Marc not-a-mathlete Morano, “one or even 2″ is the equivalent of “several.” For Morano, even basic math and simple word choice is twisted beyond the bounds of reason. No doubt in the next version of the children’s game of Telephone that Morano plays with himself, he’ll claim that Latif is predicting a century of cooling.
But Morano’s false headline — and Will’s false statement — all derive from the link Morano provides to … yes, another New Scientist story — the origin of a lot of this confused Latif nonsense, which begins:
Forecasts of climate change are about to go seriously out of kilter.
One of the world’s top climate modellers said Thursday we could be about to enter one or even two decades during which temperatures cool.
How is it possible that a scientist who says that he doesn’t have faith in the skill or accuracy of his projections after 2015 can constantly be quoted as predicting the future over the next one or even two decades? Two reasons.
First, as “The Way Things Break” explained at length, “This was not an explicit prediction by Latif — it was a hypothetical scenario that is a real, if not necessarily likely, possibility.”
Hypothetically, it could happen — hypothetically, monkeys could fly out of my butt — but Latif was most certainly not predicting it.
How do I know? I asked him, something that has gone out of fashion.
Again, Latif simply doesn’t make predictions beyond 2015. As he told me, his model has “no skill” after that, which is to say it has no accuracy, and so “my only forecast is to 2015.” Indeed, he told me “I can’t really predict two decades in the future.”
Their model has nothing whatsoever to do with anthropogenic global warming, and so it has no bearing whatsoever on the long-term temperature trend. They do model internal ocean-driven fluctuations around that trend, but if the temperature rise stalls for any length of time, the major impact is that subsequently, the temperature rise accelerates.
Second, there is another source of confusion. Let’s look in more detail at the paper’s key figure, the one that looks at past and (forecast) future global temperatures, “Hindcast/forecast decadal variations in global mean temperature, as compared with observations and standard climate model projections” (click to enlarge)
Let me once again try to explain this complicated figure.
The first thing to know about the figure — indeed, one major source of confusion — is that “each point represents a ten-year centred mean.” That is, each point represents the average temperature of the decade starting 5 years before that point and ending 5 years after that point.
Second, the red line is the actual global temperature data from the UK’s Hadley Center for Climate Prediction and Research. Why does the red line stop in 1998 and not 2007? Again, it is a running 10-year mean, and the authors use data from a Hadley paper that ends around 2003 (I believe), so they can’t do a ten-year centered mean after 1998.
Third, the black line is one of the IPCC scenarios, A1B. It is a relatively high-CO2-growth model — but actual carbon emissions since 2000 have wildly outpaced it (see here).
Fourth, the solid green line is the “hindcast” of the authors — how well their model compares to actual data (and the A1B scenario). It is then extended (in dashes) through 2010 and finally to 2025, where it meets up with A1B, since their model only imposes decadal variability on the inexorable climb of human-caused global warming.
[Fifth, the short purple line is with radiative forcing (i.e greenhouse gas concentrations) frozen at 2000 levels, which, of course, didn’t happen.]
So you can clearly see that the green line rises and then plateaus, repeatedly, until it really starts to take off in the decade of the 2010s. Perhaps the source of much of the media’s confusion is that the authors describe their results in the final line of the abstract this way:
Our results suggest that global surface temperature may not increase over the next decade, as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming.
But what they mean by that statement is not what a simple reading of that sentence would suggest: They do not mean that “the global surface temperature may not increase over the next ten years starting now.” What they mean is what the lead author, Dr. Noel Keenlyside, wrote me [in 2008] when I asked for a clarification:
Thus, based on our results we don’t expect an increase in the mean temperature of the next decade (2005-2015).
They are predicting no increase in average temperature of the “next decade” (2005 to 2015) over the previous decade, which, for them, is 2000 to 2010! And that’s in fact precisely what the figure shows — that the 10-year mean global temperature centered around 2010 is the roughly the same as the mean global temperature centered around 2005.
The authors have not predicted the next 10 years won’t see any warming. They have, however, offered an explanation for why temperatures have not risen very much in recent years, and, perhaps, why ocean temperatures have also not risen very much in the past few years (see here). Dr. Keenlyside continues:
However, as you correctly point out, our results show a pick up in global mean temperature for the following decade (2010-2020). Assuming a smooth transition in temperature, our results would indicate the warming picks up earlier than 2015.
Again, at that point, Dr. Keenlyside reiterates the disclaimer that this analysis can’t be used for year-by year predictions. Indeed, he notes that his main conclusion is not really quantitative, but qualitative:
Given the uncertainties that exist in such kinds of preliminary studies, I believe it is more useful to point out that climate on decadal timescales may be quite different from that expected only considering external radiative forcing (as in the IPCC). This is actually an obvious, but I believe mostly overlooked fact. Our results highlight this.
I would add two points. First, as you can clearly see in the figure — the actual observed
runnning average temperatures from the Hadley Center since 1995 have been between the IPCC scenario projection and Dr. Keenlyside’s forecast, which does suggest that his model may be underestimating warming. Indeed, the lack of agreement between the model’s “hindcast” and actual temperatures since 1995 should remind us again to view this only as a very preliminary analysis with predictive ability that is much more qualitative than quantitative.
Second, this general prediction — internal variability leading to slower than expected warming in recent years through 2010, followed by accelerated warming — is almost exactly the same prediction that the Hadley Center made last summer in Science (see here). They concluded:
… at least half of the years after 2009 predicted to exceed the warmest year currently on record.
… [2014 will] “be 0.30° ± 0.2°C warmer than the observed value for 2004.”
Similarly, the US Naval Research Lab and NASA just predicted in a new Geophysical Research Letters study (see “here“):
From 2009 to 2014, projected rises in anthropogenic influences and solar irradiance will increase global surface temperature 0.15 ±0.03 °C, at a rate 50% greater than predicted by IPCC.
So I take all three of these admittedly preliminary short-term forecasts to suggest that warming is going to be a roller coaster ride, with much short-term variation, but we are probably going to get quite hot quite fast early in the 2010s.
One final caveat: After reading my first draft of the 2008 post (which I subsequently revised), Dr. Keenlyside wrote me, “All our figures are decadal means, and it is hard to say (due to high frequency internal variability) at which point [after 2010] a rapid increase will occur.” That is, his study does not necessarily predict the rapid warming will actually start, in say, 2011, though his results are not inconsistent with that possibility. He reiterates that his paper is not designed to make such detailed year-by-year predictions. Indeed, the paper was designed to show that any such predictions are complicated by decadal-scale climate factors.
So I think it is quite safe to say that:
- The work of Dr. Latif and Dr. Keenlyside in Nature “does not allow one to make any inferences about anthropogenic global warming,” as Dr. Latif put it to me.
- Their work has no forecasting skill after 2015. Indeed, Latif told me “we don’t trust our forecast beyond 2015.”
- Dr. Latif is not making any predictions about what will happen after 2015 — other than that the long-term temperature warming trend driven by anthropogenic GHGs will continue and that the near-term temperature trend must catch up with the long-term trend, likely during a period of rapid warming.
- Reporters are going to keep getting this wrong.
- Deniers are going to keep getting pretty much everything wrong.
Latif told me that at the request of the NYT, he submitted an op-ed to clarify his work. That will clear things up once and for all. Or not.
As a great sage once said, “Anyone who isn’t confused here doesn’t really know what’s going on.”
UPDATE: More from Deep Climate: anatomy-of-a-lie-how-morano-and-gunter-spun-latif-out-of-control and here.