Wesley Smith in his blog Secondhand Smoke wrote that we have no reason to trust "global warming alarmists" because they have been wrong so often in the past. His argument comes from a Forbes op-ed written by a senior from the Heartland Institute, a libertarian think-tank.
There are five claims from the Forbes article Mr. Smith quotes and those will be the ones I focus on. My focus will be on the validity of these claims and to a lesser extent, his larger thesis. I won't be arguing against it per se, rather seeing whether his argument is valid. (That is, confirming that the premises are true and the conclusion follows logically.)
Heavy Snowfall: expected or not?
The UN Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report was…straightforward… “Milder winter temperatures will decrease heavy snowstorms,” IPCC reported. That was in 2001. Now, however, with an unprecedented number of major winter snowstorms hitting the northeastern U.S. during the past two winters, the alarmists are clamming up and changing their tune…Mr. Taylor's claim is a relatively popular one and requires a trip to the Third Assessment Report in order to verify the context; you will note no timescale is reported.
The section is from the second part of the report, the one that focuses on the impacts of climate change. It was hard to find more information to say over what time period they've expected snow. Keep in mind that many of the predictions are averages and pertain to the long-term global trend rather than a short-term regional trend.
Kilimanjaro and Himalayan Glaciers
The alarmists used to claim global warming was causing the retreat of Kilimanjaro’s mountain snowcap, but scientists now understand that local deforestation is the culprit. IPCC claimed in its 2007 assessment that global warming would likely melt the Himalayan glaciers by 2035, but IPCC now admits there is no scientific basis for such an assertion.The glacier incident Mr. Taylor reports is true. We should be careful to avoid assuming the entire report is as errant as the chapter or section the error appeared in, but certainly this is a red flag that the entire report needs more scrutiny.
On the other hand, there is actually a debate on the cause of Kilimanjaro's melting, with some scientists arguing it is at least partially caused by global warming and others saying its caused by something peculiar to the region. So it isn't a resolved area. Also, I haven't found anyone claiming it was due to global warming prior to when research suggested that was actually a reasonable idea—just a number of articles reassuring people it wasn't due to global warming.
Increased Temperatures
IPCC claimed in its 1990 assessment that global temperatures should rise 0.6 degrees Celsius between 1990 and 2010, yet NASA satellite data show global temperatures warmed by merely half that amount, at most.Mr. Taylor says this is an example of claimed "settled science" but the report doesn't report it too confidently, because it cites a margin of error for per decade warming, 0.2-0.5 and notes other scenarios which show more modest warming. It is true the IPCC claimed that and were wrong, but their claim was not given in complete confidence, and indeed the organization writes that a number of factors are "partially understood." So it is correct to say the IPCC's projection is wrong, but incorrect to say they considered it 'settled science.'
The Score
In a sense, the premises are mostly right: Himalyan Glaciers are really not going to melt that quickly and the IPCC projections were too high. Let's give him the Kilimanjaro one too, since scientists are on the fence. The problem is that Mr. Taylor is not only claiming scientists were wrong, but that these were claimed by 'alarmists' to be areas of 'settled science.'
There is a certain ambiguity here: who exactly is a 'global warming alarmist'? Are all scientists who support human-caused global warming alarmists? The people at the IPCC? Environmentalists? Politicians who favor stricter carbon emissions controls? Science journalists?
The ambiguity leaves Mr. Smith and Mr. Taylor in danger of equivocation (changing the meaning of a word as you argue) and makes it hard to figure out who they're claiming once made assurances that the science was settled in the cases where turned out to not be settled at all. Looking at the scientists who originated the research, few (if any) seem to be as confident as Mr. Smith and Mr. Taylor say they were. Also, the Himalayan mistake came from the IPCC and not the scientists the report typically draws from.
The Argument's Logic
It seems as though there's dubious logic here regardless of how the argument is interpreted. I see there being two cases how it could be interpreted:
- Scientists were the ones claiming these facts were 'settled.' This follows logically, but isn't true.
- Non-scientists were the ones claiming these facts were 'settled.' This is true, but logically invalid: wrong statements from non-scientists don't invalidate science.
There is another interpretation. Mr. Smith and Mr. Taylor are merely saying popular advocates for the theory of climate change are wrong in the extent of some of their predictions. This is logical, but their quotes from scientists themselves suggest Mr. Smith and Mr. Taylor feel the scientists are wrong as well (or want to make that implication). Also, it seems like they feel they've weakened theories of climate change implicating humans, a rather dubious proposition.
Unless I'm missing something significant, the argument fails to deliver. It is good to note here that when you post someone else's op-ed, make sure it's a good argument and not just one you agree with. I have no intent of proving it either way, only advancing the argument by eliminating weak arguments.
Oh, feel free to submit other claims for me to verify—I want to look at claims you find dubious.
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