The Powerline blog has done an excellent job of summarizing the issues surrounding the Climatgate/CRUtape Letters in the past couple of days. Since they reference WUWT in the most recent article, it seems relevant to also post here.
It seems Dr. Jones frets about the “weather, not climate” issue that we have been so often chastised for, whenever WUWT covers a record cold event, or a record snow event. We’ve seen quite a few of those lately. It seems CRU is concerned this “weather” may become a trend. Maybe they’ll just blame it on China and SO2 emissions. There’s an app for that. – Anthony
We’ve written about the leaked emails and other documents from the University of East Anglia’s Climatic Research Center here, here and here. Another intensely interesting email thread, which doesn’t seem to have gotten much notice, relates to the fact that the last decade, contrary to the alarmists’ predictions, has tended to get cooler, not warmer.
At the end of 2008, the scientists at East Anglia predicted that 2009 would be one of the warmest years on record:
On December 30, climate scientists from the UK Met Office and the University of East Anglia projected 2009 will be one of the top five warmest years on record. Average global temperatures for 2009 are predicted to be 0.4∞C above the 1961-1990 average of 14 ∫ C. A multiyear forecast using a Met Office climate model indicates a rapid return of global temperature to the long-term warming trend, with an increasing probability of record temperatures after 2009.
We know now that the alarmists’ prediction for 2009 didn’t come true. What’s interesting is that in January of this year, another climate alarmist named Mike MacCracken wrote to Phil Jones and another East Anglia climatologist, saying that their predicted warming may not occur:
Your prediction for 2009 is very interesting…and I would expect the analysis you have done is correct. But, I have one nagging question, and that is how much SO2/sulfate is being generated by the rising emissions from China and India…. While I understand there are efforts to get much better inventories of CO2 emissions from these nations, when I asked a US EPA representative if their efforts were going to also inventory SO2 emissions (amount and height of emission), I was told they were not. So, it seems, the scientific uncertainty generated by not having good data from the mid-20th century is going to be repeated in the early 21st century (satellites may help on optical depth, but it would really help to know what is being emitted).
That there is a large potential for a cooling influence is sort of evident in the IPCC figure about the present sulfate distribution–most is right over China, for example, suggesting that the emissions are near the surface–something also that is, so to speak, ‘clear’ from the very poor visibility and air quality in China and India. So, the quick, fast, cheap fix is to put the SO2 out through tall stacks. The cooling potential also seems quite large as the plume would go out over the ocean with its low albedo–and right where a lot of water vapor is evaporated, so maybe one pulls down the water vapor feedback a little and this amplifies the sulfate cooling influence.
Now, I am not at all sure that having more tropospheric sulfate would be a bad idea as it would limit warming–I even have started suggesting that the least expensive and quickest geoengineering approach to limit global warming would be to enhance the sulfate loading…. Sure, a bit more acid deposition, but it is not harmful over the ocean…. Indeed, rather than go to stratospheric sulfate injections, I am leaning toward tropospheric, but only during periods when trajectories are heading over ocean and material won’t get rained out for 10 days or so.
In any case, if the sulfate hypothesis is right, then your prediction of warming might end up being wrong. I think we have been too readily explaining the slow changes over past decade as a result of variability–that explanation is wearing thin. I would just suggest, as a backup to your prediction, that you also do some checking on the sulfate issue, just so you might have a quantified explanation in case the prediction is wrong.
Otherwise, the Skeptics will be all over us–the world is really cooling, the models are no good, etc.
Sulphur dioxide, like carbon dioxide, is emitted as a result of industrial activity. Unlike carbon dioxide, it is actually a pollutant. But whereas carbon dioxide tends to warm, sulphur dioxide tends to cool, and MacCracken suggests that SO2 emissions from China and India may well be offsetting the temperature impact of CO2. The net effect of human activity, therefore, may be much closer to neutral than the alarmists have been claiming.
How did the British scientists, whose careers are committed to the proposition that human activity is causing catastrophic warming of the globe, respond? Surprisingly, Tim Johns reacted with insouciance:
Mike McCracken makes a fair point. I am no expert on the observational uncertainties in tropospheric SO2 emissions over the recent past, but it is certainly the case that the SRES A1B scenario (for instance) as seen by different integrated assessment models shows a range of possibilities. In fact this has been an issue for us in the ENSEMBLES project, since we have been running models with a new mitigation/stabilization scenario “E1″ (that has large emissions reductions relative to an A1B baseline, generated using the IMAGE IAM) and comparing it with A1B (the AR4 marker version, generated by a different IAM). The latter has a possibly unrealistic secondary SO2 emissions peak in the early 21st C – not present in the IMAGE E1 scenario, which has a steady decline in SO2 emissions from 2000. The A1B scenario as generated with IMAGE also show a decline rather than the secondary emissions peak, but I can’t say for sure which is most likely to be “realistic”.
The impact of the two alternative SO2 emissions trajectories is quite marked though in terms of global temperature response in the first few decades of the 21st C (at least in our HadGEM2-AO simulations, reflecting actual aerosol forcings in that model plus some divergence in GHG forcing). Ironically, the E1-IMAGE scenario runs, although much cooler in the long term of course, are considerably warmer than A1B-AR4 for several decades! Also – relevant to your statement – A1B-AR4 runs show potential for a distinct lack of warming in the early 21st C, which I’m sure skeptics would love to see replicated in the real world… (See the attached plot for illustration but please don’t circulate this any further as these are results in progress, not yet shared with other ENSEMBLES partners let alone published). We think the different short term warming responses are largely attributable to the different SO2 emissions trajectories.
So far we’ve run two realisations of both the E1-IMAGE and A1B-AR4 scenarios with HadGEM2-AO, and other partners in ENSEMBLES are doing similar runs using other GCMs. Results will start to be analysed in a multi-model way in the next few months. CMIP5 (AR5) prescribes similar kinds of experiments, but the implementation details might well be different from ENSEMBLES experiments wrt scenarios and their SO2 emissions trajectories (I haven’t studied the CMIP5 experiment fine print to that extent).
Got that? Here is a translation: assumptions about SO2 emissions do have a “quite marked…impact” on global temperatures under the warmists’ various models. What impact they have varies from model to model. Which model is correct (if any)? Who knows? But as a result of increased SO2 in the atmosphere, there is “potential for a distinct lack of warming in the early 21st C.”
That must come as a great relief, since everyone involved in this exchange has been telling the public that global warming is an imminent catastrophe. But no! The prospect of a “distinct lack of warming in the early 21st C[entury]” is bad, because “skeptics” would “love” it!
Phil Jones, Director of the Climate Research Unit, now weighs in. Does he welcome the idea that, contrary to his own predictions, there may be little or no warming in coming decades? No!
I hope you’re not right about the lack of warming lasting till about 2020. I’d rather hoped to see the earlier Met Office press release with Doug’s paper that said something like -half the years to 2014 would exceed the warmest year currently on record, 1998!
Still a way to go before 2014.
I seem to be getting an email a week from skeptics saying where’s the warming gone. I know the warming is on the decadal scale, but it would be nice to wear their smug grins away.
Better that the Earth experience the cataclysm of global warming than that the skeptics be proved right? It makes one wonder how seriously Jones believes in the catastrophe of global warming. Jones then frets about whether the weather is really as cool as the weathermen are saying:
Chris – I presume the Met Office continually monitor the weather forecasts. Maybe because I’m in my 50s, but the language used in the forecasts seems a bit over the top re the cold. Where I’ve been for the last 20 days (in Norfolk) it doesn’t seem to have been as cold as the forecasts.
So the very climate scientists who keep saying that global warming will be an unparalleled disaster for humanity are telling the Earth: Heat up, damn it!
But let’s go back to the main point. Apparently the alarmist climatologists acknowledge that SO2, frequently emitted in conjunction with CO2, nullifies, wholly or in part, any warming tendency associated with the CO2. What is the net effect? This is, obviously, an empirical, quantitative question. But these scientists can’t answer it, not only because each of their models gives a different answer, but because they have no idea how much SO2 is being emitted by the main countries that produce that pollutant, India and China. Having no idea what the facts are, their models are useless. It does appear, however, that one obvious alternative to impoverishing humanity in a most-likely-futile effort to stave off global warming would be emitting a whole lot of SO2 over the ocean, and continuing those emissions indefinitely rather than banning them as is currently contemplated by the warmists’ models.
Climate science is in its infancy, and every proposition is controversial. What climate scientists like those at East Anglia don’t know dwarfs what they do know. They can produce a model for every occasion, but are the models any good? If so, which one? One thing we know for sure is that they don’t generate reliable predictions. In every scientific field other than global warming, a scientific hypothesis that generates false predictions is considered disproved. When it comes to global warming, however, there is no such thing as falsification. Which is the ultimate evidence that the alarmist scientists are engaged in a political enterprise, not a scientific one.
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