Key Global Warming Study May Have Bad Mathematics

An anonymous reader writes "Berkeley physics professor Richard A. Muller writes that a key study showing a sudden 'hockey stick shape' increase in global temperature may be flawed from bad mathematics. Stephen McIntyre and Ross McKitrick say that Michael Mann's computer program handled data normalization incorrectly and exaggerated data with a hockey stick shape." Update: 10/18 18:26 GMT by J : Alas for the environment, it looks like McKitrick and McIntyre have been refuted. "In previous rounds of the debate, Lambert has shown that McKitrick messed up an analysis of the number of weather stations, showed he knew almost nothing about climate, flunked basic thermodynamics, couldn't handle missing values correctly and invented his own temperature scale. But Tim's latest discovery really takes the cake."

Comments

Junk science strikes again

[Anonymous Coward]

For a group of techno-nerds who supposedly present themselves as independent thinkers, cynics, and skeptics, I see a lot of you buying into these environmental reports from the government, and the various international agencies.

The facts are quite clear. There is no proof for man-made global warming. Between solar cycles, the cycles of ice-ages, and other complex atmospheric and land-based occurrences, it would appear that we have very little to do with any of it. There were times of extreme heat and extreme cold long before we were here. Temperatures have been on a slow, and natural climb, since the last ice age, as you would expect. Most of the increases in the 20th century occurred before we even had any big industry. One cannot dismiss volcanoes and other natural forces that created the atmosphere in the first place.

There is a long history of anti-American, anti-technology fanaticism that works to destroy successful enterprises and nations. The enviro extremists fall into that category quite nicely. Did you ever notice how they never mention one shred of evidence that they might have miscalculated, or might be wrong altogether? It rarely happens in real science that your theories are perfectly accurate throughout your experimentation, especially when the real evidence shows contrary results. Maybe that's because they're not presenting real science.

It just so happens that the very small, agenda driven, socialized, government-paid scientific community is the only one that buys into the extremist theories. 19,000 independent scientists and engineers came forward two years ago to show that the evidence being presented for global warming was not science, but rather pseudoscience and rhetoric. These were people who were the best in their fields from all over the world and their concerns were understandably focused on the bogus Kyoto Treaty. They sucessfully debunked the enviro theories and showed quite a bit of evidence that described the exact opposite of the "Chicken Little" doomsday theories.

Even many liberals are leaving the ranks of the extremist environmentalist groups. Largely because the groups have shown themselves to be fraudulent. The scare tactics from those groups are created to keep the money rolling in, so they can promise to present a solution that is waiting for a problem. If everything is OK, as is the case, we don't need them, and that's their greatest fear. Let's not forget that they focus all their attentions on the big metropolitan areas for their supposed research and completely ignore the outlying areas, the weather balloon tests, and the satellite results, all of which show a slight cooling trend lately. Sure, we can create heat islands, but that is not global, and certainly should not require punitive actions. And why is it that it's always the US that gets the blame? We produce more than any other country, support a good portion of the world through foreign aid, and follow some of the strictest standards for emissions. It's cowardly to point the finger at us and ignore countries like China, India, and the third world nations who live in heavily polluted, heavily populated areas where no research is being done to clean things up.

I would suggest that everybody follow the money trail and where ultimate power is being created. Follow your instincts of skepticism and dig deeper to find the real facts. Figure out what it is that concerns you the most about the future and why so many people seem to ignore our sovereignty and Constitutional rights to freedom and are so quick to buy into junk science. Remember what our forefathers were insinuating when they stated: "He who sacrifices a little freedom to gain a little security, will lose both, and deserves neither". Don't fall into the trap of allowing bogus results determine what we're all allowed to do and not do for the remainder of human civilization.

Re:Junk science strikes again

[node 3]

There is a long history of anti-American, anti-technology fanaticism that works to destroy successful enterprises and nations.

Nobody complains about a country that is the most kind, most efficient, least belligerent, most enlightened, etc. They complain when a country rides high atop the shoulders of the poor and pretends its success is due entirely to its morally superior system of Capitalism.

It's not success, progress, or technology that riles the world, it's the subjugation of the morality of the human to the morality of the dollar. You and your philosophical brethren like to claim that the concerned citizens of the world want to throw the world back to the stone-age, but in fact they want to make sure that human progress is both fairly distributed, and that it doesn't consume the resources of the world at an unsustainable rate.

Right now, the US is the worst offender. In a few decades it will likely be China. How would you like it if China polluted the air (imagine smog warnings in Seattle, Portland, San Francisco and LA being subject to the whim of China's industrial sector) and claimed anyone who complains is an "anti-Chinese", anti-technology fanatic?

Progress is good, we all love it, but it must be sustainable, rational, and equitable.

Re:Junk science strikes again

[squiggleslash]

Let me see if I understand this correctly.

You're dismissing the entire global warming issue, something backed up by study after study, by independent scientists, on the basis of two arguments:

1. Independent scientists (scientists who are not working for a particular agenda) tend to work in government funded institutions (eg universities) and are therefore, by being funded by government, part of some "agenda driven, socialized, government driven" conspiracy.

2. ONE study has turned out to have a mathematical flaw in its model.

This argument makes sense to you why?

I'd also say that comments like

Even many liberals are leaving the ranks of the extremist environmentalist groups.

show that by and large it is people like you, so keen to discredit global warming, who have the extremist agenda driven views. So what if some liberals do not like Greenpeace? What on Earth does this have to do with anything? If Al Gore makes a speech at the Sierra Club, do CO2 emissions decrease signficantly? If Ralph Nader rips up his Green Party Membership card, does this act as a catalyst, increasing the degree to which CO2 traps heat on Earth?

The case for global warming is solid and backed up by the figures. The case for the mechanics of greenhouse effects is also solid. The case that CO2 levels are higher in the atmosphere today than they were 50 years ago is also solid. The case that human activity is resulting in a greater amount of CO2 being added to the atmosphere than would otherwise happen would appear to be self-evident - we're taking carbon stocks that would otherwise lie under the ground and we're literally burning them up, and we're replacing natural carbon sinks with deserts of tarmac and concrete.

What we're still trying to work out is the degree of the link between the first (global warming), and the last (our excessive CO2 production.) We're trying to work out what the affects of the first (global warming) will be on the weather (we're getting closer and closer all the time.) All of these are subjects that require research. But we can safely say that anyone who says, right now, on the basis of the evidence available, that there is simply no link whatsoever from the latter to the former is a kook. We may or may not be the primary cause of global warming, but to argue that we're having no affect would be to argue that either the concept of a greenhouse effect is flawed or that we're simply not increasing the overall amount of CO2 in the air despite all the logical evidence that we are.

And those who dismiss the concept rarely if ever address either issue, instead they point to problems with computer models predicting future temperature increases, or they complain that other factors may also be affecting the temperature, as if to say that because other factors are affecting it, we can't possibly be.

Re:Junk science strikes again

[DougWebb]

The case for global warming is solid and backed up by the figures.

True; temperatures have been rising for 300 years or so.

The case for the mechanics of greenhouse effects is also solid.

Largely true; we know that CO2 and water vapor in the atmosphere hold in heat, and that water vapor holds in much more. We also know that this effect is critical for keeping our planet from freezing solid.

We also know that increasing CO2 levels have a minor impact as a greenhouse gas, but may cause a domino effect: the small addition of heat from CO2 might cause more water vapor to stay in the atmosphere, which could have a large heating effect. But it's also possible that a counter-balancing mechanism would kick in to prevent this. The latter seems likely, since we know there have been periods in history with much higher CO2 levels than today, but without runaway global warming.

The case that CO2 levels are higher in the atmosphere today than they were 50 years ago is also solid.

True, and the rate seems to be increasing as well. From 1900 to 1940 CO2 levels rose around 18%, and from 1940 to 2000 they rose around 80%.

However, most of the warming that occured between 1900 and 2000 occurred before 1950. It seems that rising CO2 levels follow warmings, rather than preceed them. This suggests that the higher temperatures are causing the higher CO2 levels, rather than the other way around.

The case that human activity is resulting in a greater amount of CO2 being added to the atmosphere than would otherwise happen would appear to be self-evident - we're taking carbon stocks that would otherwise lie under the ground and we're literally burning them up, and we're replacing natural carbon sinks with deserts of tarmac and concrete.

Not really true. Sure, we're taking carbon out of the ground and releasing it into the atmosphere, but only 2/3 of it seems to stay there; reabsorption occurs, and may be able to hold more than we know. Furthermore, our contribution may be insignificant compared to what the earth is releasing. As I stated above, CO2 increases seem to be caused by higher temperatures (perhaps released from warmer oceans) and that contribution might be much more than we release.

We're not really replacing the carbon sinks either. In some areas we might be, but it's a fact that the forests in the United States, and probably much of the rest of the world, are growing in size, largely due to the higher amount of CO2 in the atmosphere. Pine trees grow up to three times faster at today's CO2 levels than at the levels in 1900, and all other plants grow faster too (anywhere from 10% to 300%, depending on species and conditions.) This could very well be the 'counter-balance' mechanism that prevents runaway global warming; higher CO2 levels cause the vegetative carbon sinks to grow more plentiful.

For more on all of this, watch this seminar from the Oregon Institute of Science and Medicine.

If only they had caught this earlier...

[node 3]

It would have been nice had they caught this error earlier. Then maybe we could have avoided this year's barrage of hurricanes.

Oh well, at least they caught it well before winter sets in. This should help prevent any severe snow storms and blizzards this season.

Alternative solutions

[FooAtWFU]

The problem with some people who worry about global warming is that they have a tendency to say that severely reducing carbon dioxide emissions is the only way to prevent disaster- and while that's a lovely sentiment, it is excessively impractical. But what of alternative solutions to the problem?

A mere 0.5 percent change in Earth's net reflectivity, or albedo, would solve the greenhouse problem completely. ... About 1 percent of the United States is covered by human constructions, mostly paving, suggesting that we may already control enough of the land to get at the job.

It's a whole lot more likely than cutting emissions 30% or more.

Re:Study rejected by the science magazine Nature

[crmartin]

No, Mueller's article is based on several studies, which includes one short article that was rejected for space reasons, and a previous article (December 2003) that examines McIntyre and McKittrick's original, peer-reviewed and published article. Go read the referenced web sites.

Anyone who has done real science for any length of time knows that the perr-review process is not without flaws. In this particular case, though, McIntyre and McKittrick have identified flaws in the original hockey-stick paper that have already been the subject of a major correction in Nature and have published several peer-reviewed papers on the errors in the original Mann et al paper.

Note also that Mann et al. don't seem to be able to settle on which data series they used, and refuse to make their source data and codes available to other researchers.

It's also interesting that the models of Mann et al. deny the Little Climatic Optimum, which is otherwise awfully well supported, eg, by the historical records of the Vikings in the New World and the rather clear records of conditions in Europe.

As with most things of this sort, you should read the actual sources and draw your own conclusions.

So?

[Black Parrot]

Mathematics aside, it's a bit late to be asking whether global warming is happening or not. The question for us now is whether we can stop the ongoing meltdown. The arctic, Antartica, the Greenland ice sheet, Glacier National Park, the Alps - all melting before our eyes.

Nemesis

[bcrowell]

Interesting to see this coming from Rich Muller, who was my favorite prof as an undergraduate at Berkeley. At that time (1983), he was working on an idea that there was a periodicity to mass extinctions caused by comet impacts. He thought the sun might actually be a double star, and its companion might be too dim and far away to have been detected. This star, which he called Nemesis, would come close to the Oort cloud every 30 Myr (?) as it approached the sun in its elliptical orbit, and knock a bunch of comets out of their normal orbits. The whole thing was based on a statistical analysis of the dates of impacts, and the problem was that some impacts were more accurately dated than others, so he threw out the ones with inaccurate dates. Skeptics argued that he had produced the periodicity by throwing out certain data. They searched for the companion star with IR astronomy (?), but never found it. Muller wrote a very entertaining popular science book about the whole thing.

So anyway, one of the biggest episodes in Muller's scientific career was built on a controversial statistical analysis. He dealt with a lot of the same issues he's talking about now with respect to the hockey stick graph: doing Monte Carlo simulations, worrying about biases in the data, etc. Probably a case of once burned, twice wary.

Re:The 'Little Ice Age'

[jerkface]

I have to reply, because there are too many things wrong in this post for it to have such a high score.

The Little Ice Age in Europe from 1400-1850 is now thought to have been caused by an abnormal lack of SUNSPOTS. Sunspots cause the sun to give off alot more heat/energy than a nicely uniformed surface sun does.

Sunspots don't cause more energy to come from the sun - the fact is that sunspots are cooler than the rest of the sun's surface. Sunspots are, however, symptoms of an active sun. Just as low levels of sunspots occur when the sun is less active.

Too bad we only have about 1,000 years of data on sunspots.

Sunspots have been directly observed and recorded in reasonable detail only since Galileo's time. But in another sense, we actually have data going back much farther than that. During periods of high solar activity, the sun bombards the earth with a larger number of subatomic particles. This type of radiation results in constant isotope formation - in particular, this is why things left exposed on the earth's surface keep a constant concentration of Carbom 14. Isotope ratio measurements have in fact been used to infer changes in solar activity for periods during which nobody was recording sunspot counts.

Also, while higher solar activity heats the earth, the main part of the effect is actually very indirect. Most of the extra heating associated with a hotter sun cannot be explained by radiation alone. What happens is that the higher particle flux strengthens the earth's magnetosphere, and somewhat ironically, this means the atmosphere is better protected from being eroded away by solar wind precisely when solar wind is most dense! The slightly thicker "blanket" of atmosphere allows the earth to retain a bit more heat.

This fact doesn't completely debunk the manmade global warming hypothesis. Changes in solar activity probably "only" account for 75% of the climate change since the end of the Little Ice Age. The other 25% could all easily be the work of mankind. But there are two reasons I don't think we should panic yet. First, there's mounting evidence that the Medieval Warm Period (which preceded the Little Ice Age) peaked at levels even warmer than what we now experience. So modern temperatures aren't really unprecedented. Secondly, all of the four previous interglacials peaked at much higher temperatures than ours has. So, a very long view of climate shows that on fairly regular intervals, the earth experiences temperatures similar to those we now have, even without any help from mankind.

My Rich Muller Story...

[rjh]

When I was seventeen I read Muller's Nemesis: the Death Star. I suspect that title was foisted on him by his publisher; it's too sensationalistic for Dr. Muller, I think. Anyway, yes, Rich Muller is the guy who came up with the Nemesis hypothesis.

I loved the book. It wasn't a one-sided argument in favor of his theory. Rather, the book was more about the history of his hypothesis rather than "look at me, I'm so cool". (For all that I love Linus Pauling, he did a lot of the latter in his writing.) The book made mention of some experiments which could disprove the Nemesis hypothesis, and I waited for the results of the Hipparcos sat... and didn't hear anything in the media.

So, with the simple wisdom of a seventeen-year-old, I decided to write Rich Muller and ask him the results of Hipparcos. I mentioned how I'd found his book, that I was going to college next year to pursue an engineering degree, the usual stuff a seventeen-year-old talks about.

Three weeks later, I had a two-page letter back from him. He explained the Hipparcos results; he wished me luck in my undergraduate career; and asked me to drop him a line in a couple of years to let him know how my engineering studies were going.

I never got around to responding to Rich, because by the time I got to my undergraduate career I'd become infected with the common wisdom of adults: "of course he's got better things to do than hear from me." When I was seventeen I knew better; when I was twenty, I was an idiot.

Well, now I'm looking at 30 in a couple of months. So. Rich, if you're reading this?

The 17-year-old from the early '90s who wrote you asking about Hipparcos? That's me. I'm now 29 and working towards a Ph.D. in Computer Science. It's been a helluva ride, let me tell you. I'm basically doing applied math, and some of the ways the math gets applied take my breath away.

Thanks for taking me seriously when I was seventeen. Only a couple of people did.

Re:The 'Little Ice Age'

[mc6809e]

There is a nice graph here showing the slight increase in the sun's average output during periods of high sunspot activity.

It appears there is an increase of 2 watts/m^2 at the earth's distance from the sun.