That Precautionary Principle

October 10, 2018

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Long ago, when it was still acceptable to voice doubts about computer projections of the climate apocalypse, people often answered critics who mentioned the uncertainty in the predictions by citing “The Precautionary Principle.”  This self-evident axiom of risk management means that if the consequences of a low-risk, uncertain event are so catastrophically awful, we are prudent to act as though the event will happen.  So, even if the predictions about climate change are not very certain, the impacts on us if they turn out to be true are so horrific, we might as well not argue, and just assume that they are correct.  Case closed.

When I first began to track the issues related to climate change more than twenty-five years ago, that was pretty much my point of view, but after a lot of thought, discussion, and experiences at conferences, I have modified my view to one of rather harsh skepticism.  I’m not going to discuss that process here:  I just want to dispose of this supposedly common sense precautionary principle (PP).

First, a little story:  My sister has an old friend that she has known for many years who suffered significant brain damage a long time ago when he fell and struck his head.  He is severely impaired these days, as though he had been the victim of a stroke.  He was quite robust and healthy when it happened; he just slipped on the ice one winter and banged his skull.  A fluke accident with terrible consequences.  Could happen to anyone, right?

Now, this sad event the befell my sister’s friend was forseeable.  After all, everyone knows that you can slip and fall on the ice, and many of us have done it, although with consequences that ranged more towards embarrassment than disability…but it could happen to us, even if we are not old and frail.  It happened to my sister’s friend!  The chances are not zero.  If you do research on it, you might find that they are not even considered trivial, so this is my question.  Given that the consequences of this accident, with a probability notably above zero, are so life-shattering, why don’t we all walk around wearing football helmets in the winter when there is ice on the ground?  It would seem to be a perfect and unassailable application of the precautionary principle.

The reason that we don’t wear helmets is that we all make our own calculations, knowingly or not, and assume that the risk is so vanishingly small that we need not worry about such a “fluke” happening to us.  We are totally unpersuaded by the logic of the PP.  Some people are so foolish as to never wear seat belts despite the much stronger statistical evidence in their favor.  We might think those people are nuts, but still not don the helmet in icy weather.

In the end, we are left with nothing but data, and our judgment about how powerful a case it makes for taking action.  The PP is simply a way of trying to shut down consideration of the data and the possible courses of action by asserting that only one alternative is possible and logical, but in practice, nobody reasons that way when they actually have to make a choice.

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Mad Science/Journalism Experiment

October 10, 2018

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In the wake of the new IPCC special report, the NYTimes declared (emphasis added) in its editorial today:

…the world must utterly transform its energy systems in the next decade or risk ecological and social disaster, attention must be paid….

The panel said a mammoth effort is needed, beginning now and carrying through the century, to decarbonize global energy systems. The next 10 years are absolutely crucial: Emissions will have to be on a sharp downward path by 2030 for any hope of success. Greenhouse gases must be cut nearly in half from 2010 levels. Renewable energy sources must increase from about 20 percent of the electricity mix today to as much as 67 percent. The use of coal would need to be phased out, vanishing almost entirely by midcentury.

Okay, so there we have it.  A clear and stunning prediction of doom, the End Times of the Climate Apocalypse are nigh!  2030 is not so far off, and a very large proportion of the readers of this post (all three of you!) are likely to be around then to test the propositions pronounced in the editorial.

My prediction is that in before 2030, if people are still excited about this issue, we will see articles about how new studies have put off the day of reckoning to 2040 or 2050, the standard moving the goalposts routine.  Or, they may declare that the delay of crisis is due to the heroic (unspecified) reductions in GHG accomplished as a result of their indomitable advocacy.  If I am wrong, I won’t be happy!  😦


Microsurfing

October 6, 2018

Maybe you can tell what these are, some of them anyway.  They were taken with my Celestron digital microscope.  Click on the thumbnails to see an enlarged image.

 


Hot Time, Summer in the City…

September 11, 2018

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I just cannot stop thinking about this graph that appeared with this article in the NYTimes recently.  The piece discussed how the number of hot summer days, those above 90 degrees F, are projected to increase in the future, and it allows readers to enter their town and date of birth to see how the weather has changed between then and now.

Hmmm….  Well, we all know that climate is always changing, and we all know that it is warmer now, in general, than it was 100 years ago, but beyond that what does this article and its interactive graphic tell us?

I imagine that a lot of readers misinterpret the data plot and believe that it represents the rise in temperature in NYC over the recorded period:  my experience is that most readers of these articles in the Times are not too concerned with details of data and data presentation.  In fact, it is more accurate to say that the chart shows the number of “above 90-degree F days” in NYC over the period.  That is, a count of days, not temperatures.   Except that it doesn’t show that…  On the left there is some text that says that it shows the “average number of days above 90-degrees F.”  What does that mean?

If we look at the data point for the year 2010, we find a value of about ten days.  Ten days above 90F in 2010?  You could easily check the record to see if that is accurate. But the text says that ten days is the “average number” in 2010.  In that year, there were either ten days above 90F or there were not ten days.  An average does not enter into the discussion.  That would be as if we said that June, on average, has thirty days.

The confusion is eliminated when we read the FAQ and Methodology document to which a link is provided at the end of the article:  How many people do that, do you think?  We learn that the data plot shows a twenty-year moving average of the above 90F days for each year.  For example, for the year 2000, the number of above 90F days for 1990,1991, 1992…2000…2008, 2009, 2010 are added up and and divided by twenty-one (there are twenty-one years’ values) and an average is obtained.  For 2001, the same process is used, but the summed years begin with 1991 and end with 2011.  Moving averages are often used to smooth out the data curve:  in this case, without doing it the plot would be very “spiky” with sudden changes in the number of above 90F days from year to year.  Smoothing the data gives a better idea of the trend, but it is good practice to make clear up front that you have done so, which the authors of the piece do not do.

On the other hand, what about the years 2008 through 2018?  For example, take the year 2015:  we get a twenty-year moving average by summing the data from 2005 to 2015, and adding that to the data for 2016 to 2026…  Oops!  There is NO DATA for the years after 2017!!  The kindly scientists at the Climate Impact Lab of Columbia University have used model data, simulated data, or shall we say, created data in place of actual historical data.  They do, obliquely, note this fact in their FAQ and Methodology text, but you’d never know it by looking at the graph.

Consider this:  their models show temperatures rising and above 90F days increasing, so the tendline after 2017 is rising.  But unlike the rest of the graph, that is NOT actual recorded data.  For all we know, the data record during that period is flat, or perhaps moving downward.

And speaking of flat data records, at least in NYC, the period from 1990 to 2017 (keeping in mind that the data for 2008 to 2017 is not actually the historical data) looks pretty much horizontal, i.e. constant, not increasing.  But sure enough, we can be completely confident that the upward trend that begins…next year, will come about.

Well, we cannot be completely sure because the Climate Lab also tells us – they are honest, if not forthcoming – that the results plotted here represent the data range that two-thirds of the models project.  I’m used to hearing the IPCC and other outfits talk about high or very high confidence in projections, i.e. a 90 or 95% confidence interval, but here we have a “just likely,” …mebbe… confidence interval of 66%.  Of course, this is simply a statistical sample of modeled results, described with the unspoken assumption that the models are correct, or nearly correct, or more correct than not correct… 🙂  If all the models share a few assumptions and parameters that later are disproved, then the fact that 66% predict this is hardly something to inspire confidence.  This, by the way, goes for all the climate projection models.

It would be nice if this graph for NYC were to be published every year in the NYTimes.  Then we could see each year how accurate the projections actually were.  Instead, this plot will be forgotten, and next year there will be a new batch, showing the rise in this or that frightful metric after the fateful year at hand.

Of course, it could happen exactly the way they are claiming it will.  We shall see…!


New Age Prophet

January 4, 2015

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I rouse myself from my leisured sloth to comment on the latest pronouncement by the prophet of doom, Naomi Oreskes.  Today the New York Times, that newspaper “of record,” has seen fit to give her a lot of space to continue her attack on the scientific method:  Playing Dumb on Climate Change.

Ms. Oreskes has a Ph.D., and is a professor at Harvard, so she is instantly given credence as a reliable expert, but her work, on which I have commented extensively, is pretty much at the level of hack polemic as far as I am concerned.  From her sylvan altars – doesn’t she just look the part of the serious, concerned, and not to be trifled with Mother Nature? – she makes some of the most outrageous pronouncements to be heard from the academic realm on the topic of global warming.  Okay…let’s see what she said this time.

Her gripe is that scientists are too conservative about the risks of global warming – they should be ringing alarm bells, as she does, warning us of the horrors to come and pushing for the solutions that she supports.  Note that there is significant scientific controversy about many of the claims that Ms. Oreske makes, e.g. that recent extreme weather events are clear evidence of the negative impacts of burning fossil fuels, and that her argument is, therefore, neatly circular.  It amounts to this:  scientists who are not screaming about the coming End of Days are too conservative, period!

She goes on to discuss a central notion of the scientific method:

We’ve all heard the slogan “correlation is not causation,” but that’s a misleading way to think about the issue. It would be better to say that correlation is not necessarily causation, because we need to rule out the possibility that we are just observing a coincidence.

This is typical of her method.  She doesn’t say that correlations always indicate a clear causal chain, but she doesn’t want to rule it out, either. Who would?  But she wants to make it seem that scientists that won’t jump on the bandwagon of this or that theory simply because they are not more than 95% sure that the correlation is not chance are missing essential risks.  But how do you decide when to jump on, and when not to?  When she thinks you should?  When you’re scared enough to ignore evidence and jump to conclusions?

She’s very worried about Type 2 errors:   being too conservative and missing causes and effects that are really there.  I would ask, too conservative for whom or what?  Here we are moving from the realm of science to that of policy and politics.  It is certainly true that when one creates policy, the scientific standard is too strict – policy makers cannot always wait for better information.  But then, one must make a case for the preponderance of risk warranting action now, rather than later.  Ms. Oreskes won’t do that:  she simply avoids having to make the case by attacking the scientific method.  Circularity again.

The dilemma that this opinion piece presents us with is obliquely indicated by Ms. Oreskes here:

When applied to evaluating environmental hazards, the fear of gullibility can lead us to understate threats.

Clearly, we can make the converse argument that lack of caution can lead to overestimating threats, wasting money, disrupting lives, ordering medical tests with high likelihood of false-positives…all sorts of bad stuff.  She doesn’t consider this.  When we face this obvious fact, we are back at Square One:  Ms. Oreskes, prove your case with facts!  This is exactly the discussion she seeks to short-circuit.  Because she knows she’s right.  She sees.  She is a Prophet.


The 97% Solution

July 18, 2014

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I often read that 97% of climate scientists agree with “the consensus” on anthropogenic global warming (AGW), so I decided to finally buckle down and read the article that has given the latest currency to this claim.  You can read it too, right here.  The heart of it is contained in Table No.3:

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You can see the 97.1% figure there, right in the first row.  Done deal!  But what does this really mean?  Read for yourself, but here’s a summary:

  • About 12,000 abstracts of papers on “climate” were culled from the Web, and distributed without names to twelve “citizen-science” researchers for rating.
  • About 9,000 expressed no position on AGW.
  • Of those that expressed a position, 97% “endorsed” the “consensus” view.  What does that mean?  Actually, the “endorsed” label was applied to any of three expressed positions to make the analysis simpler.  To receive that rating, the abstract had to take one of the following positions:
    • Explicitly state that humans are the primary cause of recent global warming
    • Explicitly state humans are causing global warming, or refer to anthropogenic global warming/climate change as a known fact
    • Imply humans are causing global warming. e.g., the research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause

Pretty broad array of opinion there all rolled up into that 97%, which is actually only 97% of the 1/3 that expressed a position.  Could it be that those that did not express a position, 63%, just think it’s a trivial affair, not worth discussing?    And of those that did express “affirmation,” it seems that just mentioning that CO2 does cause the earth to warm – no mention of how much, or over what period, or whether or not it is worrisome – puts you down with the “consensus” position.

So, we can state pretty definitively that those writers of published scientific papers who chose to express a view of AGW, do overwhelmingly agree that CO2 is a greenhouse gas and that human activity – not just burning fossil fuels – is contributing to changes in the climate.  That’s a pretty safe set of propositions, but then, it is the nature of consensus to state the non-controversial.

NB:  There is absolutely no mention of the real crux of the controversy, i.e., what to make of the projections for the next fifty and one hundred years that are contained in the IPCC Assessment Reports and other publications.


Men of Green

June 24, 2014

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Mssrs. Rubin, Bloomberg, and Paulson have sponsored a new report on the economic impact of climate change:  These are all guys you can trust, right? Hmm… well, being green doesn’t mean just thinking about money, does it?

Actually, I have to hand it to them – they’re going to make lots of money no matter what happens, so I don’t believe that they have some nefarious financial scheme up their sleeves:  they really believe it!  Well, good for you, boys!

Rubin was heard pontificating about how climate change poses an “existential threat” to…us?  civilization?  the USA?  The nuclear standoff during The Cold War, now that was an existential threat!  Poverty, lack of sanitation, malaria, AIDS, those are existential threats to people in a lot of the world.  I’m not so convinced about climate change.

Paulson is certain that we are at a tipping point for the planet, something that has been heard repeatedly from different quarters for the last fifty years.   And then, there’s the money:  valuable assets may go south once the warming starts and people realize they don’t want to burn coal anymore, or so he thinks.  Seems also that millions of beachfront lots will be flooded and eventually destroyed.  Isn’t that going on now?  And farming will be disrupted, something that has happened before.  Anybody recall The Dustbowl?  We recovered.

Justin Gillis is the writer of the Times’ article, and this bit of his is so over the top, I’m wondering where his editor was:

Heat and humidity will probably grow so intense that spending time outside will become physically dangerous, throwing industries like construction and tourism into turmoil.

I don’t get that…if the climate of, say, NY, is going to shift south, i.e., become more like that of Georgia, are we to believe that the American South is currently a place where it is physically dangerous to go outside?  Even if you’re white?  C’mon, I mean Jim Crow is over, so even black people sit outside.

I could go on…