Climate models undermine global warming skeptics

Along with the usual blather I hear on right-wing talk shows, there's a fresh falsity being spread over the airwaves: computer climate models are unsophisticated attempts to mirror changes in the Earth's weather and shouldn't be trusted.

This isn't true. So don't believe global warming skeptics like George Taylor, who isn't Oregon's state climatologist but likes to pretend that he is.

I heard Taylor spout his uninformed criticisms of climate models on KPAM's Victoria Taft show. Since those models show both that global climate change is going to be an increasingly serious problem, and that humans are responsible for a large share of the rise in carbon dioxide that is helping to drive global warming, ExxonMobil supported pseudo-scientists like Taylor try to discredit the models.

Recently Taft echoed the unscientific party line, claiming that the models don't include basic factors that affect the climate. Such as, Taft said, "the sun." I suspect she meant to say sunspots, or some other subtlety of solar radiation, but that wasn't what came over my car radio. I remember hearing: "Gosh, those models don't even include the sun. How crazy is that?"

Well, not crazy at all. Because Taft and Taylor don't know what they're talking about. Here's the graphical bottom line that proves them wrong, courtesy of the Woods Hole Research Center, along with a couple of paragraphs of Woods Hole commentary.

Look, read, and believe in the models. (As noted in the commentary, "forcing" means an influence on global temperature; "anthropogenic" means human-caused.)

For example, recorded global temperature change can be compared with computer models that predict temperature change under different "forcing" scenarios, (with "forcings" signifying external influences on the solar radiative budget of the planet - greenhouse gases, aerosols, increased solar radiation, and other agents). Fig. 2 above compares observed temperature anomalies from the historic mean (red line) with the results of computer models that attempt to predict temperature based on the interactions of other environmental influences (gray line).

The top two charts in the figure illustrate that models using natural and anthropogenic influences alone [(a) Natural Forcing Only & (b) Anthropogenic Forcing Only] fail to match the observed record of temperature anomalies since 1866. But the combination of natural and anthropogenic models [(c) Natural + Anthropogenic Forcing] produces a close match to the measured data. This is seen as a clear "thumbprint" of human impacts on climate change.

These graphs also are in Alan J. Thorpe's informative (and readable) paper, "Climate Change Prediction: A challenging scientific problem." Thorpe starts out by saying:

Predictions of future climate change, based on numerical global climate models, are the critical outputs of climate science. Whilst much has been written about the details of the predictions themselves, skepticism about the prediction models is rife and this is why this paper is devoted to de-mystifying the prediction methodology…There is little doubt that a lack of knowledge about how climate change is predicted and the associated uncertainties are amongst the main reasons for ill-informed comment on climate change.

And he concludes with:

So why do commentators imagine that top scientists are deluded about anthropogenic climate change? The stakes are high and rarely are scientists under such scrutiny. Scientists are appalled that they could be suspected of distorting the evidence to enhance their reputations or funding opportunities. Of course scientific hypotheses and analysis can be refuted by later discoveries but this is not the same as complicity. The fact that everyone experiences weather and climate may explain why nonscientists feel confident in attempting to refute the scientific evidence.

The complexity of the climate system and its many interacting and compensating physical processes means that simple arguments that gloss over this complexity have to be approached with a significant degree of scepticism. A common method of arguing starts by identifying a single cause or physical process that either has not been included or has been included in an imperfect way, into climate models. But the climate changes because of a multiplicity of interacting processes and any one process alone cannot be the whole story.

The search for the one and only cause of climate change is doomed to failure. Climate modellers attempt to include in the models all the processes that are even remotely likely to have a detectable effect – any newly discovered process will quickly find itself incorporated into the models!

So be highly skeptical of global climate change skeptics. Thorpe says that the models they dismiss with off-hand comments ("doesn't even include the sun!") have about three-quarters of a million lines of computer code.

Compare that with the miniscule iota of sense made by global warming deniers such as George Taylor and Victoria Taft. Believe the models, not them.

 

Comments

[Rain]

Good column. Last night Bill Maher brought this all up on his HBO show, Real Time. Carly Fiorina, the ex CEO for HP made the point that it's better to do something and hope it makes a difference than the reverse. What do we lose by improving gasoline mileage-- unless we work for an oil company that profits from excess usage. The ones out there fearing that we will improve air quality mystify me other than it's the same old battle-- never enough profit, never enough excess. To begin, they won't be the ones paying the price for global climate change accompanied by massive flooding. It will be mostly the poorest. Although the super storms that are predicted might surprise some of these people who could care less and only follow a political agenda, not one that seeks to look at facts.

[Ken Shull]

Please stop using RIGHT WING in every sentence -- you sound like a true crackpot

http://www.ocs.orst.edu/staff/gt.html

George H. Taylor is the State Climatologist for Oregon, and a faculty member at Oregon State University's College of Oceanic and Atmospheric Sciences. He manages the Oregon Climate Service, the state repository of weather and climate information, and supervises a staff of ten.

Mr. Taylor is past president of the American Association of State Climatologists. He is a member of the American Meteorological Society and has received certification as a Certified Consulting Meteorologist by the Society. He also has a California Lifetime Community College Credential. He has published over 200 reports, symposium articles, and journal articles.

Prior to joining Oregon State University in 1989, Mr. Taylor operated his own consulting business in Santa Barbara, California. Previously he was employed as a meteorologist by North American Weather Consultants and Environmental Research and Technology.

Education: B.A. Mathematics U.C. Santa Barbara, 1969
M.S. Meteorology University of Utah, 1975

Family: Married; 3 children

[Ken Shull]

[Caution: no peer-reviewed scientific evidence is cited here. So be highly doubtful that what is said is anything more than a personal opinion. My new blog policy is to add this cautionary statement when someone posts a comment that confuses the facts about global warming. See:
http://hinessight.blogs.com/hinessight/2007/02/global_warming_.html
--Brian]

Remember Global Cooling?
Why scientists find climate change so hard to predict.

http://www.msnbc.msn.com/id/15391426/site/newsweek/

How did NEWSWEEK—or for that matter, Time magazine, which also ran a story on the subject in the mid-1970s—get things so wrong? In fact, the story wasn't "wrong" in the journalistic sense of "inaccurate." Some scientists indeed thought the Earth might be cooling in the 1970s, and some laymen—even one as sophisticated and well-educated as Isaac Asimov—saw potentially dire implications for climate and food production. After all, Ice Ages were common in Earth's history; if anything, the warm "interglacial" period in which human civilization evolved, and still exists, is the exception. The cause of these periodic climatic shifts is still being studied and debated, but many scientists believe they are influenced by small changes in the Earth's orbit around the Sun (including its "eccentricity," or the extent to which it deviates from a perfect circle) and the tilt of its rotation. As calculated by the mathematician Milutin Milankovitch in the 1920s, these factors vary on interlocking cycles of around 20,000, 40,000 and 100,000 years, and if nothing else changed they would be certain to bring on a new Ice Age at some time. In the 1970s, there were scientists who thought this shift might be imminent; more recent data, according to William Connolley, a climate scientist at the British Antarctic Survey who has made a hobby of studying Ice Age predictions, suggest that it might be much farther off.

[Ken Shull]

No one knows how many millions of volcanoes have erupted all over the world in the last 600 million years; - - any one of which might have expelled more CO2, CO, sulfuric acid, and other toxic substances than all of mankind has done in the past thousands of years.

The earth recovered.

In that 600 million years, the earth has gone through periods of tropical climate at very high latitudes, as well as ice ages with glacial ice half-way to the equator. During most of the world’s history, the poles were not covered by ice and snow. None of the above was due to human influences.

The earth recovered.

Many so-called experts have forecast disasters ranging from the coming of ice ages, to the millennium-time-change fiasco.

Very likely the earth will recover nicely again, - it didn’t need Al Gore’s help in the previous 600 million years.

[Brian]

Ken, I suspect you haven't watched "An Inconvenient Truth." At least, you don't seem to have understood a key undisputed fact.

Carbon dioxide levels in the atmosphere now are at unprecedented levels, higher than at any time in the past 700,000 years, I recall from the movie.

This is clearly human caused. So whatever happened in the past isn't a reliable guide to the future, because humans are a new influence on climate change.

Gore points out in the movie that a certain difference in CO2 levels produced two mile thick ice sheets. He then points to the much larger difference being observed now, in the opposite warming direction and asks, "What will this produce?"

Excellent question. One that must be addressed scientifically, not by falling back on "nature knows best" platitudes. We are part of nature now. And humans need to decide what is best for our survival.

[Paul Burch]

Firstly as Ken says, if the earths climate was that unstable, it could not have supported and nurtured life for the past millenia.The atmosphere would by now have been driven off by the huge fuel air explosions as suggestedin the recent British Sunday Times Special!!!!

Secondly, and I know that Mr Gore rather CONVENIENTLY overlooked this, the earths temperature changes over the last 700,000 years have LED the change in CO2 by about 800 years. THAT IS TEMP CHANGES FIRST AND THEN CARBON CHANGES LATER!!! Do a search - it's true.

Thirdly why is the atmosphere not warming rapidly at 30,000ft as predicted by the Carbon led Global Warming models?

Fourthly, why is the IPCC ignoring the recent evidence for Cosmic Radiation effects on the global temperature as influenced by sunspot activity. The stronger the sunspot activity the warmer the earth becomes due to less ionising radiation that helps to form clouds, and cloud cover cools the earth. The suns magnetic field doubled in strength during the 20th century. More sunspots = higher global temperatures.

I'm not right wing. I am in favour of reducing carbon fuel use big time. I am in favour of the best use of science to inform and direct, not the current misuse to disinform and further certain anti mankind political goals.