Posts tagged ‘Michael Mann’

Want to Make Your Reputation in Academia? Here is an Important Class of Problem For Which We Have No Solution Approach

Here is the problem:  There exists a highly dynamic, multi- multi- variable system.  One input is changed.  How much, and in what ways, did that change affect the system?

Here are two examples:

  • The government makes a trillion dollars in deficit spending to try to boost the economy.  Did it do so?  By how much? (This Reason article got me thinking about it)
  • Man's actions increase the amount of CO2 in the atmosphere.  We are fairly confident that this has some warming effect, but how how much?  There are big policy differences between the response to a lot and a little.

The difficulty, of course, is that there is no way to do a controlled study, and while one's studied variable is changing, so are thousands, even millions of others.  These two examples have a number of things in common:

  • We know feedbacks play a large role in the answer, but the system is so hard to pin down that we are not even sure of the sign, much less the magnitude, of the feedback.  Do positive feedbacks such as ice melting and cloud formation multiply CO2 warming many times, or is warming offset by negative feedback from things like cloud formation?  Similarly in the economy, does deficit spending get multiplied many times as the money gets respent over and over, or is it offset by declines in other categories of spending like business investment?
  • In both examples, we have recent cases where the system has not behaved as expected (at least by some).  The economy remained at best flat after the recent stimulus.  We have not seen global temperatures increase for 15-20 years despite a lot of CO2 prodcution.  Are these evidence that the hypothesized relationship between cause and effect does not exist (or is small), or simply evidence that other effects independently drove the system in the opposite direction such that, for example, the economy would have been even worse without the stimulus or the world would have cooled without CO2 additions.
  • In both examples, we use computer models not only to predict the future, but to explain the past.  When the government said that the stimulus had worked, they did so based on a computer model whose core assumptions were that stimulus works.  In both fields, we get this sort of circular proof, with the output of computer models that assume a causal relationship being used to prove the causal relationship

So, for those of you who may think that we are at the end of math (or science), here is a class of problem that is clearly, just from these two examples, enormously important.  And we cannot solve it -- we can't even come close, despite the hubris of Paul Krugman or Michael Mann who may argue differently.    We are explaining fire with Phlogiston.

I have no idea where the solution lies.  Perhaps all we can hope for is a Goedel to tell us the problem is impossible to solve so stop trying.  Perhaps the seeds of a solution exist but they are buried in another discipline (God knows the climate science field often lacks even the most basic connection to math and statistics knowledge).

Maybe I am missing something, but who is even working on this?  By "working on it" I do not mean trying to build incrementally "better" economics or climate models.  Plenty of folks doing that.  But who is working on new approaches to tease out relationships in complex multi-variable systems?

I Was Reading Matt Ridley's Lecture at the Royal Society for the Arts....

... and it was fun to see my charts in it!  The lecture is reprinted here (pdf) or here (html).  The charts I did are around pages 6-7 of the pdf, the ones showing the projected curve of global warming for various climate sensitivities, and backing into what that should imply for current warming.  In short, even if you don't think warming in the surface temperature record is exaggerated, there still has not been anywhere near the amount of warming one would expect for the types of higher sensitivities in the IPCC and other climate models.  Warming to date, even if not exaggerated and all attributed to man-made and not natural causes, is consistent with far less catastrophic, and more incremental, future warming numbers.

These charts come right out of the IPCC formula for the relationship between CO2 concentrations and warming, a formula first proposed by Michael Mann.  I explained these charts in depth around the 10 minute mark of this video, and returned to them to make the point about past warming around the 62 minute mark.   This is a shorter video, just three minutes, that covers the same ground.  Watching it again, I am struck by how relevant it is as a critique five years later, and by how depressing it is that this critique still has not penetrated mainstream discussion of climate.  In fact, I am going to embed it below:

The older slides Ridley uses, which are cleaner (I went back and forth on the best way to portray this stuff) can be found here.

By the way, Ridley wrote an awesome piece for Wired more generally about catastrophism which is very much worth a read.

Update on My Comment Policy: It's Not This

In the Climategate 2.0 emails, Michael Mann confirms what we already knew - there is absolutely no tolerance for dissent, even the scientifically thoughtful sort, among climate alarmists.  Writing about their mother-site, RealClimate, Mann says

 I suspect you've both seen the latest attack against [Keith Briffa's] Yamal work by McIntyre.    Gavin and I (having consulted also w/ Malcolm) are wondering what to make of this, and what sort of response---if any---is necessary and appropriate. So far, we've simply deleted  all of the attempts by McIntyre and his minions to draw attention to this at RealClimate.

Note that the knee-jerk, default action is to purge, hide, and delete criticism, even before it is understood.  They make absolutely no attempt to understand the argument, reading it just enough to know that it is critical and therefore must be deleted.  The second action is to find someone to refute it, again even before the critique is understood.  It is critical of us so it must be wrong.  QED.

Here is one of the original McIntyre posts where he outlines the problem he found in Briff's work.  He argues that the findings in Briffa are not very robust, as substitution of a larger sample of trees (this is a tree-ring temperature reconstruction study, like the hockey stick) from the same area for Briffa's apparently small, hand-picked sample have an astoundingly large effect on the study's findings (the red study line below, McIntyre's reconstruction in black).

Perhaps McIntyre was missing something (though over the 2 years since no one involved has suggested what that might be).  But the tone of the article is certainly scientific and thoughtful.   It has no resemblance to the unscientific polemic that alarmists often use as an excuse to excise skeptical comments from their web sites.

My Favorite Climategate 2.0 Email (so far)

I am working on a summary post of the new batch of climategate emails, but this is perhaps my favorite.  It is written to Andy Revkin, nominally a reporter for the NY Times but revealed by the new emails to be pretty much the unpaid PR agent of Michael Mann and company.  Over and over, emails from Mann and his cohorts get Revkin to write the articles they want, drop quotes from skeptics from articles, and in general coordinate communications policy.

Anyway, one climate scientist writes Revkin this note

I think the notion of telling the public to prepare for both global warming and an ice age at the same [time] creates a real public relations problem for us.

Amazing that this actually had to be said.

Update:  Revkin is currently an opinion blogger but at the time of the emails he was supposed to be a news reporter at the NYT.

Did CLOUD Just Rain on the Global Warming Parade?

Today in Forbes, I have an article bringing the layman up to speed on Henrik Svensmark and this theory of cosmic ray cloud seeding.  Since his theory helped explain some 20th century warming via natural effects rather than anthropogenic ones, he and fellow researchers have face an uphill climb even getting funding to test his hypothesis.  But today, CERN in Geneva has released study results confirming most of Svensmark's hypothesis, though crucially, it is impossible to infer from this work how much of 20th century temperature changes can be traced to the effect (this is the same problem global warming alarmists face -- CO2 greenhouse warming can be demonstrated in a lab, but its hard to figure out its actual effect in a complex climate system).

From the article:

Much of the debate revolves around the  role of the sun, and though holding opposing positions, both skeptics and alarmists have had good points in the debate.  Skeptics have argued that it is absurd to downplay the role of the sun, as it is the energy source driving the entire climate system.  Michael Mann notwithstanding, there is good evidence that unusually cold periods have been recorded in times of reduced solar activity, and that the warming of the second half of the 20th century has coincided with a series of unusually strong solar cycles.

Global warming advocates have responded, in turn, that while the sun has indeed been more active in the last half of the century, the actual percentage change in solar irradiance is tiny, and hardly seems large enough to explain measured increases in temperatures and ocean heat content.

And thus the debate stood, until a Danish scientist named Henrik Svensmark suggested something outrageous -- that cosmic rays might seed cloud formation.  The implications, if true, had potentially enormous implications for the debate about natural causes of warming.

When the sun is very active, it can be thought of as pushing away cosmic rays from the Earth, reducing their incidence.  When the sun is less active, we see more cosmic rays.  This is fairly well understood.  But if Svensmark was correct, it would mean that periods of high solar output should coincide with reduced cloud formation (due to reduced cosmic race incidence), which in turn would have a warming effect on the Earth, since less sunlight would be reflected back into space before hitting the Earth.

Here was a theory, then, that would increase the theoretical impact on climate of an active sun, and better explain why solar irradiance changes might be underestimating the effect of solar output changes on climate and temperatures.

I go on to discuss the recent CERN CLOUD study and what it has apparently found.

A Really Bad Idea

Regular readers will have no doubts about my skepticism of the theory of catastrophic man-made global warming.  In particular, in these pages and at Climate Skeptic, I have repeatedly criticized the details of Michael Mann's work on the hockey stick.  I won't repeat those issues today, though some of the past articles are indexed here.

That being said, efforts by Republicans in Virginia to bring legislative or even criminal action against Mann for his work when he was at the University of Virginia is about the worst idea I have heard in quite some time.  Though nominally about forcing public disclosure (something I am always in favor of from state entities) the ultimate goal is to drag Mann into court

Cuccinelli has said he wants to see whether a fraud investigation would be warranted into Mann's work, which showed that the earth has experienced a rapid, recent warming

[As an aside, this is actually NOT what Mann's hockey stick work purports to show.  The point of the hockey stick is to make the case that historic temperatures before 1850 were incredibly stable and flat, and thus recent increases of 0.6-0.8C over the last 150 years are unprecedented in comparison.   His research added nothing to our knowledge about recent warming, it was on focused on pre-industrial warming.   The same folks that say with confidence the science is settled don't even understand it].

For those frustrated with just how bad Mann's work is and upset at the incredible effort to protect this work from criticism or scrutiny by hiding key data (as documented in the East Anglia climategate emails), I know it must feel good to get some sort of public retribution.  But the potential precedent here of bringing up scientists on charges essentially for sloppy or incorrect work is awful.

Bad science happens all the time, completely absent any evil conspiracies.  Human nature is to see only the data that confirms ones hypotheses and, if possible, to resists scrutiny and criticism.  This happens all the time in science and if we started hauling everyone into court or into a Senate committee, we have half of academia there  (and then likely the other half when the party in power changed).  Team politics are a terrible disease and the last thing we need is to drag them any further into science and academia.

Science will eventually right itself, and what is needed is simply the time and openness to allow adversarial scrutiny and replication within academia to run its course.  Seriously, are we next going to drag the cold fusion guys in to court?  How about all the folks in the geology field that resisted plate tectonics for so long.  Will we call to account the losers in the string theory debate?

If legislators want to help, they can

  • Make sure there are standards in place for archiving and public availability of any data and code associated with government funded research
  • Improve the governments own climate data management
  • Ensure that state funding is distributed in a way to support a rich dialog on multiple sides of contested scientific issues.

Climate Updates

Believe it or not, I am not going to update on the CRU emails.  The insights into the science process are illuminating, and confirm much that we have suspected, but faults in transparency do not automatically win the game -- they lead to [hopefully] future transparency which then allows for better criticism and/or replication of the work.

My frustration today is a recent article in Scientific American [with the lofty academic title "Seven Answers to Climate Contrarian Nonsense"] which purports to shoot down the seven key skeptics arguments.  Many others have shown how the author does not do a very good job of shooting down these seven, but that is not my main frustration.  The problem is that, like many of the global warming myth buster articles like this, the author completely fails to address the best, core arguments of skeptics, preferring to snipe around at easier prey at the margins.

In this post, I discuss his article and suggest 7 better propositions alarmists should, but never do, address.

You can see discussion of all of these in my recent lecture, on video here.

Don't have 90 minutes?  Richard Lindzen of MIT has a great summary in the WSJ that mirrors a lot of what I delve into in my video.

Here are my seven alternative skeptics' claims I would like to see addressed:

Claim A: Nearly every scientist, skeptic and alarmist alike, agree that the first order warming from CO2 is small.  Catastrophic forecasts that demand immediate government action are based on a second theory that the climate temperature system is dominated by positive feedback.  There is little understanding of these feedbacks, at least in their net effect, and no basis for assuming feedbacks in a long-term stable system are strongly net positive.   As a note, the claim is that the net feedbacks are not positive, so demonstration of single one-off positive feedbacks, like ice albedo, are not sufficient to disprove this claim.  In particular, the role of the water cycle and cloud formation are very much in dispute.

Claim B: At no point have climate scientists ever reconciled the claims of the dendroclimatologists like Michael Mann that world temperatures were incredibly stable for thousands of years before man burned fossil fuels with the claim that the climate system is driven by very high net positive feedbacks.   There is nothing in the feedback assumptions that applies uniquely to CO2 forcing, so these feedbacks, if they exist today, should have existed in the past and almost certainly have made temperatures highly variable, if not unstable.

Claim C: On its face, the climate model assumptions (including high positive feedbacks) of substantial warming from small changes in CO2 are inconsistent with relatively modest past warming.  Scientists use what is essentially an arbitrary plug variable to handle this, assuming anthropogenic aerosols have historically masked what would be higher past warming levels.  The arbitrariness of the plug is obvious given that most models include a cooling effect of aerosols in direct proportion to their warming effect from CO2, two phenomenon that should not be linked in nature, but are linked if modelers are trying to force their climate models to balance.  Further, since aerosols are short lived and only cover about 10% of the globe's surface in any volume, nearly heroic levels of cooling effects must be assumed, since it takes 10C of cooling from the 10% area of effect to get 1C cooling in the global averages.

Claim D: The key issue is the effect of CO2 vs. other effects in the complex climate system.  We know CO2 causes some warming in a lab, but how much on the real earth?  The main evidence climate scientists have is that their climate models are unable to replicate the warming from 1975-1998 without the use of man-made CO2 -- in other words, they claim their models are unable to replicate the warming with natural factors alone.  But these models are not anywhere near good enough to be relied on for this conclusion, particularly since they admittedly leave out any number of natural factors, such as ocean cycles and longer term cycles like the one that drove the little ice age, and admit to not understanding many others, such as cloud formation.

Claim E: There are multiple alternate explanations for the 1975-1998 warming other than manmade CO2.  All likely contributed (along with CO2) but it there is no evidence to give most of the blame to Co2.  Other factors include ocean cycles (this corresponded to a PDO warm phase), the sun (this corresponded to the most intense period of the sun in the last 100 years), mankind's land use changes (driving both urban heating effects as well as rural changes with alterations in land use), and a continuing recovery from the Little Ice Age, perhaps the coldest period in the last 5000 years.

Claim F: Climate scientists claim that the .4-.5C warming from 1975-1998 cannot have been caused natural variations.  This has never been reconciled with the fact that the 0.6C warming from 1910 to 1940 was almost certainly due mostly to natural forces.  Also, the claim that natural forcings could not have caused a 0.2C per decade warming in the 80's and 90's cannot be reconciled with the the current claimed natural "masking" of anthropogenic warming  that must be on the order of 0.2C per decade.

Claim G: Climate scientists are embarrassing themselves in the use of the word "climate change."  First, the only mechanism ever expressed for CO2 to change climate is via warming.  If there is no warming, then CO2 can't be causing climate change by any mechanism anyone has ever suggested.   So saying that "climate change is accelerating" (just Google it) when warming has stopped is disingenuous, and a false marketing effort to try to keep the alarm ringing.  Second, the attempts by scientists who should know better to identify weather events at the tails of the normal distribution and claim that these are evidence of a shift in the mean of the distribution is ridiculous.  There are no long term US trends in droughts or wet weather, nor in global cyclonic activity, nor in US tornadoes.  But every drought, hurricane, flood, or tornado is cited as evidence of accelerating climate change (see my ppt slide deck for the data).  This is absurd.

In Any Other Context, This Would Be Quackery

I am reading a speech by Michael Mann, the author of the now famous climate hockey stick, which has been criticized by statisticians and climatologists alike.  In particular, I am fascinated by the claim that "there is a 95 to 99% certainty that 1998 was the hottest year in the last one thousand years."

Forgetting the problems with his analysis, and forgetting all the other evidence that we have that in the Medieval warm period, the earth was probably hotter than it was today, just look at that sentence on its face.  Is there any other context where we would take a scientists near certainty about the value of a climate variable 500 years before man even started measuring it as anything but quackery?  If there was a way to reasonably bet against the proposition that 1998 was the hottest year of the millennium, I would do so even as a 1:1 proposition, but would leap at the chance to take the bet at 20:1 or 100:1 odds, which is essentially what Mann is proposing when he says he is 95-99 percent certain.