Archive for the ‘Climate’ Category.

Denying the Climate Catastrophe: 2. Greenhouse Gas Theory

Other parts of the series are here:

  1. Introduction
  2. Greenhouse Gas Theory (this article)
  3. Feedbacks
  4.  A)  Actual Temperature Data; B) Problems with the Surface Temperature Record
  5. Attribution of Past Warming;  A) Arguments for it being Man-Made;  B) Natural Attribution
  6. Climate Models vs. Actual Temperatures
  7. Are We Already Seeing Climate Change
  8. The Lukewarmer Middle Ground
  9. A Low-Cost Insurance Policy

We continue our multi-part series on the theory of catastrophic man-made global warming by returning to our framework we introduced in the last chapter.

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In the introduction, we discussed how catastrophic man-made global warming theory was actually made up of two independent parts.  In this section, we will discuss the first of these two parts, the greenhouse gas effect, which is the box in the upper left of our framework.

For those unfamiliar with exactly what the greenhouse effect is, I encourage you to check out this very short primer.  Essentially, certain gasses in the atmosphere can absorb some of the heat the Earth is radiating into space, and re-radiate some of this heat back to Earth.  These are called greenhouse gasses.  Water vapor is a relatively strong greenhouse gas, while CO2 is actually a relatively weak greenhouse gas.

It may come as a surprise to those who only know of skeptics' arguments from reading their opponents (rather than the skeptics themselves), but most prominent skeptics accept the theory of greenhouse gas warming.  Of course there are exceptions, including a couple of trolls who like to get attention in the comments section of this and other blogs, and including a few prominent politicians and talk-show hosts.  But there are also environmental alarmists on the other side who have signed petitions to ban dihydrogen monoxide.  It is always tempting, but seldom intellectually rewarding, to judge a particular position by its least capable defenders.

There is simply too much evidence both from our and other planets (as well as simple experiments in a laboratory) to deny that greenhouse gasses in the atmosphere have a warming effect on planets, and that CO2 is such a greenhouse gas.   What follows in the rest of this section represents something of a consensus of people on both sides of the debate.

To investigate the effect of CO2 on Earth's temperature, we are going to use this chart:

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On the X axis is the atmospheric concentration of CO2 in parts-per-million (ppm).  Frequently, forecasts of CO2 warming are shown as a relationship over time.  I prefer this view, because it separates the assumption of CO2 emissions rates from assumptions about the sensitivity of temperatures to CO2.

Note that the concentrations we are talking about are remarkably small.  Currently the Earth is just over 400 ppm, which is 0.04%.  Only one in 2500 molecules in air is CO2.

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On the Y-axis we then have the incremental warming we might see, on average, across the surface of the Earth from increased concentrations of CO2.  Unless I point it out explicitly, we will use Celsius throughout this and later chapters.

What we now want to do is graph the relationship between the concentrations of CO2 in the atmosphere and the temperature increase of the Earth.  We will use 400 ppm and 0C increase as our starting points.  For now (and we will come back to this assumption) we will look at just the direct effect of warming from the greenhouse gas effect of CO2 and leave out any other complicated, 2nd order interactions with the Earth and its climate.

The estimate I will use comes from Dr. Michael Mann and was first cited in the early IPCC reports.  A quick note on the IPCC -- the IPCC is a body that meets every 5 years or so under the auspices of the United Nations to try to summarize the current state of climate science.  Many skeptics, including myself, would argue that the IPCC process is flawed and overly politicized, but as much as possible in this series I will try to use the IPCC position, making it explicit when I differ.  But what follows is very much IPCC canon.  In fact, I like using Michael Mann's work here because, as author of the hockey stick, he is a vocal and prominent advocate on the alarmist end of the debate and certain not in the tank for the skeptic side.

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The relationship is shown in the equation at the top (where delta T is the temperature increase and c is the atmospheric concentration in ppm).  I have graphed the equation in green because most of us do not have a good intuition for what this equation might look like.

The first thing you might note is that the line is curved, and represents a diminishing return relationship, which means that each incremental molecule of CO2 in the atmosphere has less warming effect than the last (see my short presentation on the greenhouse gas effect here).  Thus a constant rate of growth in CO2 concentrations would yield a slowing growth rate in temperatures.  This is a well-understood relationship, so much so that the sensitivity of temperature to CO2 is generally written not as degrees per ppm but as degrees per doubling of CO2 levels.  This means that the increase from 400-800 ppm would be expected to have about the same impact on temperature as the increase from 800 to 1600 ppm.

Of course, without any sense of CO2 growth rates, it's hard to relate this line to our lives.  So as a next step, we will overly some CO2 forecasts for the atmospheric levels of CO2 by 2100. [As an aside, there is a group of skeptics that think that most CO2 increases are coming from warming itself, flipping the arrow of causality, rather than from man.  There is some evidence for this proposition in ice core analysis, but I will leave it aside and for our purposes assume most CO2 increases in this century are coming from hydrocarbon combustion].

Though I think that their forecasts are exaggerated, I have taken the UN IPCC's 4 most likely CO2 cases for the year 2100 and overlayed them on the chart below:


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Taking the midpoint of these forecasts, we arrive at about 1C of warming between now and the end of the century.

So now, if you are paying attention, you may be ready to call bullsh*t on me.  Coyote, you say, every catastrophic forecast I have ever seen in the media is for WAY more than 1C of warming!  Bill McKibbon says its going to be 10 degrees of warming (and if you can't trust Harvard journalism majors on scientific issues, who can you trust?)  You are obviously lying, you evil denier.

Actually, not.  Everything in this chapter has been pretty much canon in the global warming world.  The direct, first order contribution of CO2 via the greenhouse effect is expected to be around a degree over the next century.  So whence comes the catastrophe?  As mentioned in the introduction, the catastrophe comes from a second, independent theory that the Earth's climate system is dominated by strong positive feedbacks that multiply greenhouse warming many times into a catastrophe.

If you have never heard of this second theory, don't be surprised.  In many years of reading press articles on global warming, I can't remember one that adequately explained the two-part nature of the theory that is embedded in most global warming forecasts and climate models.  But, perhaps not coincidentally, it is this second theory with which we skeptics have the most issues.  We will take this up in our next installment.

Part 3 on feedbacks can be found here.

Warren Meyer Climate Presentation at Claremont-McKenna Athenaeum

Denying the Climate Catastrophe: 1. Introduction

Last month I outlined my position on global warming to a fabulous audience at the Athenaeum at Claremont-McKenna College.  In doing so, I had a chance to substantially update my presentation materials.  I realized that it had been years since I had posted this presentation as anything but a video, and so I embark over the next several weeks to lay my position out in a multi-part written series.

Table of Contents (updated as new chapters are added)

  1. Introduction (this article)
  2. Greenhouse Gas Theory
  3. Feedbacks
  4.  A)  Actual Temperature Data; B) Problems with the Surface Temperature Record
  5. Attribution of Past Warming;  A) Arguments for it being Man-Made;  B) Natural Attribution
  6. Climate Models vs. Actual Temperatures
  7. Are We Already Seeing Climate Change
  8. The Lukewarmer Middle Ground
  9. A Low-Cost Insurance Policy

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I suppose the first question I need to answer is:  why should you bother reading this?  We are told the the science is "settled" and that there is a 97% consensus among scientists on .... something.  Aren't you the reader just giving excess credence to someone who is "anti-science" just by reading this?

Well, this notion that the "debate is over" is one of those statements that is both true and not true.  There is something approaching scientific consensus for certain parts of anthropogenic global warming theory -- for example, the fact that CO2 is a greenhouse gas and that concentrations of it in the atmosphere have a warming effect on the Earth is pretty much undisputed in all but the furthest reaches of the scientific community.

But it turns out that other propositions that are important to the debate on man-made global warming are far less understood scientifically, and the near certainty on a few issues (like the existence of the greenhouse gas effect) is often used to mask real questions about these other propositions.  So before we go any further , it is critical for us to get very clear what exact proposition we are discussing.

At this point I have to tell a story from over thirty years ago when I saw Ayn Rand speak at Northeastern University (it's hard to imagine any university today actually allowing Rand on campus, but that is another story).  In the Q&A period at the end, a woman asked Rand, "Why don't you believe in housewives?" and Rand answered, in a very snarky fashion, "I did not know housewives were a matter of belief."   What the woman likely meant to ask was "Why don't you believe that being a housewife is a valid occupation for a woman?"  But Rand was a bear for precision in language and was not going to agree or disagree with a poorly worded proposition.

I am always reminded of this story when someone calls me a climate denier.  I want to respond, in Rand's Russian accent, "I did not know that climate was a matter of belief?"

But rather than being snarky here, let's try to reword the "climate denier" label and see if we can get to a proposition with which I can agree or disagree.

Am I, perhaps, a "climate change denier?"  Well, no.  I don't know anyone who is.  The world has had warm periods and ice ages.  The climate changes.

OK, am I a "man-made climate change denier?"  No again.  I know very few people, except perhaps for a few skeptics of the talkshow host variety, that totally deny any impact of man's actions on climate.  Every prominent skeptic I can think of acknowledges multiple vectors of impact by man on climate, from greenhouse gas emissions to land use.

If you have to slap a label on me, I am a "catastrophic man-made climate change denier."  I deny the catastrophe.   Really, I would prefer "catastrophic man-made global warming denier" because there is no mechanism by which man's CO2 emissions can affect climate except through the intermediate step of warming.   The name change from "global warming" to "climate change" was, to my mind, less about science and more about a marketing effort to deal with the fact the temperatures had plateaued over the last 10-20 years and to allow activists to point to tail of the distribution weather events and call them man-made.    But we get ahead of ourselves.  We will discuss all of this in later sections.

In this series I will therefore be discussing what I will call the "Catastrophic Man-Made Global Warming Theory."   There are a lot of moving parts to this theory, so I will use the following framework as a structure for my discussion.

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This framework follows the work of the UN IPCC, an international panel that meets every 5 years or so to summarize the state of climate science in general and catastrophic man-made global warming in particular.  While I will obviously disagree with the IPCC canon from time to time, I will try to always point out when I do so.  However, I don't think any climate scientists would argue with the framework I am using here to describe their theory.

The first thing you will see, and perhaps the most important single point you should take away from this discussion, is that the core theory of catastrophic man-made global warming is actually a two part theory.  In part one, which is essentially greenhouse gas theory, a doubling of CO2 warms the Earth by a bit over 1 degree Celsius.  But there is a second part of the theory, a theory that is entirely unrelated to greenhouse gas theory.  That theory states that the Earth's climate systems are dominated by positive feedbacks which multiply the initial warming from CO2 by 3- 5 times or more.

It is this two-part theory that causes me, and many other skeptics, the most frustration in the climate debate.  For when advocates say the science is "settled," they really mean that greenhouse gas theory is pretty well accepted.  But this is only one part of a two-part theory, and in fact the catastrophe actually comes from the second theory, the theory that the climate is dominated by positive feedbacks, and this second theory is far from settled.  But again, I get ahead of myself, we will cover this all in great depth in later sections.

No theory in science has any meaning until it is confirmed by observations, so the bottom half of our framework deals with observational evidence for the theory.   The IPCC claims that the Earth has warmed about 0.8C over the last century, and that [much/substantial/most/all/more than 100%] of this warming is due to man.  The IPCC and many scientists have played with the wording of the amount of warming attributable to man over the years, and rather than deal with that complexity here, we will wait until we get to that section.  But it is fair to say that IPCC canon is that man's contribution to the warming is probably not less than half and could be more than 100%.

Finally, on the right of our framework, this man-made warming has the potential to cause all sorts of changes -- to weather patterns, to animal species, to disease vectors -- you name it.  Pick any possible negative effect -- more hurricanes, more tornadoes, more heat waves, more snow, less snow, lower crop yields, more malaria, more rain, less rain, more terrorism, rising sea levels, displaced persons, more acne, etc. etc. -- and someone has been quoted in the media claiming the link to warming.  When something bad happened in Medieval Europe, it was typically blamed on Jews or marginalized women (via witchcraft accusations).   Today, global warming is the new all-purpose target of blame.

Over many installments and several weeks, I hope to walk through this framework and discuss the state of the science (for those who can't wait, I wrote a much shorter overview here several years ago).  We will discuss parts of the science that are well-grounded -- such as man-made warming from greenhouse gas theory and the fact that the Earth has warmed over the last century.  We will discuss parts of the science I consider exaggerated -- such as the claim of large positive feedback multipliers of future warming and attribution of all past warming to man.  And we will discuss parts of the theory which, despite constant repetition in the press, have absolutely no evidence behind them whatsoever -- such as the claim that we are already seeing negative effects from warming such as more hurricanes and tornadoes.

Part 2 on the greenhouse gas theory continues here.

Coyote's Bi-Partisan Climate Plan -- A Climate Skeptic Calls For a Carbon Tax

While I am not deeply worried about man-made climate change, I am appalled at all the absolutely stupid, counter-productive things the government has implemented in the name of climate change, all of which have costly distorting effects on the economy while doing extremely little to affect man-made greenhouse gas production.  For example:

Even when government programs do likely have an impact of CO2, they are seldom managed intelligently.  For example, the government subsidizes solar panel installations, presumably to reduce their cost to consumers, but then imposes duties on imported panels to raise their price (indicating that the program has become more of a crony subsidy for US solar panel makers, which is typical of these types of government interventions).  Obama's coal power plan, also known as his war on coal, will certainly reduce some CO2 from electricity generation but at a very high cost to consumers and industries.  Steps like this are taken without any idea of whether this is the lowest cost approach to reducing CO2 production -- likely it is not given the arbitrary aspects of the program.

For years I have opposed steps like a Federal carbon tax or cap and trade system because I believe (and still believe) them to be unnecessary given the modest amount of man-made warming I expect over the next century.  I would expect to see about one degree C of man-made warming between now and 2100, and believe most of the cries that "we are already seeing catastrophic climate changes" are in fact panics driven by normal natural variation (most supposed trends, say in hurricanes or tornadoes or heat waves, can't actually be found when one looks at the official data).

But I am exhausted with all the stupid, costly, crony legislation that passes in the name of climate change action.   I am convinced there is a better approach that will have more impact on man-made CO2 and simultaneously will benefit the economy vs. our current starting point.  So here goes:

The Plan

Point 1:  Impose a Federal carbon tax on fuel.

I am open to a range of actual tax amounts, as long as point 2 below is also part of the plan.  Something that prices CO2 between $25 and $45 a ton seems to match the mainstream estimates out there of the social costs of CO2.  I think methane is a rounding error, but one could make an adjustment to the natural gas tax numbers to take into account methane leakage in the production chain.   I am even open to make the tax=0 on biofuels given these fuels are recycling carbon from the atmosphere.

A Pigovian tax on carbon in fuels is going to be the most efficient possible way to reduce CO2 production.   What is the best way to reduce CO2 -- by substituting gas for coal?   by more conservation?  by solar, or wind?  with biofuels?  With a carbon tax, we don't have to figure it out.  Different approaches will be tested in the marketplace.  Cap and trade could theoretically do the same thing, but while this worked well in some niche markets (like SO2 emissions), it has not worked at all in European markets for CO2.   There has just been too many opportunities for cronyism, too much weird accounting for things like offsets that is hard to do well, and too much temptation to pick winners and losers.

Point 2:  Offset 100% of carbon tax proceeds against the payroll tax

Yes, there are likely many politicians, given their incentives, that would love a big new pool of money they could use to send largess, from more health care spending to more aircraft carriers, to their favored constituent groups.  But we simply are not going to get Conservatives (and libertarians) on board for a net tax increase, particularly one to address an issue they may not agree is an issue at all.   So our plan will use carbon tax revenues to reduce other Federal taxes.

I think the best choice would be to reduce the payroll tax.  Why?  First, the carbon tax will necessarily be regressive (as are most consumption taxes) and the most regressive other major Federal tax we have are payroll taxes.  Offsetting income taxes would likely be a non-starter on the Left, as no matter how one structures the tax reduction the rich would get most of it since they pay most of the income taxes.

There is another benefit of reducing the payroll tax -- it would mean that we are replacing a consumption tax on labor with a consumption tax on fuel.  It is always dangerous to make gut-feel assessments of complex systems like the economy, but my sense is that this swap might even have net benefits for the economy -- ie we might want to do it even if there was no such thing as greenhouse gas warming.   In theory, labor and fuel are economically equivalent in that they are both production raw materials.  But in practice, they are treated entirely differently by the public.   Few people care about the full productive employment of our underground fuel reserves, but nearly everybody cares about the full productive employment of our labor force.   After all, for most people, the primary single metric of economic health is the unemployment rate.  So replacing a disincentive to hire with a disincentive to use fuel could well be popular.

Point 3:  Eliminate all the stupid stuff

Oddly enough, this might be the hardest part politically because every subsidy, no matter how idiotic, has a hard core of beneficiaries who will defend it to the death -- this the the concentrated benefits, dispersed cost phenomena that makes it hard to change many government programs.  But never-the-less I propose that we eliminate all the current Federal subsidies, mandates, and prohibitions that have been justified by climate change.  Ethanol rules and mandates, solar subsidies, wind subsidies, EV subsidies, targeted technology investments, coal plant bans, pipeline bans, drilling bans -- it all should go.  The carbon tax does the work.

States can continue to do whatever they want -- we don't need the Feds to step on states any more than they do already, and I continue to like the 50 state laboratory concept.  If California wants to continue to subsidize wind generators, let them do it.  That is between the state and its taxpayers (and for those who think the California legislature is crazy, that is what U-Haul is for).

Point 4:  Revamp our nuclear regulatory regime

As much as alternative energy enthusiasts would like to deny it, the world needs reliable, 24-hour baseload power -- and wind and solar are not going to do it (without a change in storage technology of at least 2 orders of magnitude in cost).  The only carbon-free baseload power technology that is currently viable is nuclear.

I will observe that nuclear power suffers under some of the same problems as commercial space flight -- the government helped force the technology faster than it might have grown organically on its own, which paradoxically has slowed its long-term development.  Early nuclear power probably was not ready for prime time, and the hangover from problems and perceptions of this era have made it hard to proceed even when better technologies have existed.   But we are at least 2 generations of technology past what is in most US nuclear plants.  Small air-cooled thorium reactors and other technologies exist that could provide reliable safe power for over 100 years.  I am not an expert on nuclear regulation, but it strikes me that a regime similar to aircraft safety, where a few designs are approved and used over and over makes sense.  France, which has the strongest nuclear base in the world, followed this strategy.  Using thorium could also have the advantage of making the technology more exportable, since its utility in weapons production would be limited.

Point 5: Help clean up Chinese, and Asian, coal production

One of the hard parts about fighting CO2 emissions, vs. all the other emissions we have tackled in the past (NOx, SOx, soot/particulates, unburned hydrocarbons, etc), is that we simply don't know how to combust fossil fuels without creating CO2 -- CO2 is inherent to the base chemical reaction of the combustion.  But we do know how to burn coal without tons of particulates and smog and acid rain -- and we know how to do it economically enough to support a growing, prosperous modern economy.

In my mind it is utterly pointless to ask China to limit their CO2 growth.  China has seen the miracle over the last 30 years of having almost a billion people exit poverty.  This is an event unprecedented in human history, and they have achieved it in part by burning every molecule of fossil fuels they can get their hands on, and they are unlikely to accept limitations on fossil fuel consumption that will derail this economic progress.  But I think it is reasonable to help China stop making their air unbreathable, a goal that is entirely compatible with continued economic growth.  In 20 years, when we have figured out and started to build some modern nuclear designs, I am sure the Chinese will be happy to copy these and start working on their CO2 output, but for now their Maslov hierarchy of needs should point more towards breathable air.

As a bonus, this would pay one immediate climate change benefit that likely would dwarf the near-term effect of CO2 reduction.  Right now, much of this soot from Asian coal plants lands on the ice in the Arctic and Greenland.  This black carbon changes the albedo of the ice, causing it to reflect less sunlight and absorb more heat.  The net effect is more melting ice and higher Arctic temperatures.  A lot of folks, including myself, think that the recent melting of Arctic sea ice and rising Arctic temperatures is more attributable to Asian black carbon pollution than to CO2 and greenhouse gas warming (particularly since similar warming and sea ice melting is not seen in the Antarctic, where there is not a problem with soot pollution).

Final Thoughts

At its core, this is a very low cost, even negative cost, climate insurance policy.  The carbon tax combined with a market economy does the work of identifying the most efficient ways to reduce CO2 production.   The economy benefits from the removal of a myriad of distortions and crony give-aways, while also potentially benefiting from the replacement of a consumption tax on labor with a consumption tax on fuel.  The near-term effect on CO2 is small (since the US is only a small part of the global emissions picture), but actually larger than the near-term effect of all the haphazard current programs, and almost certainly cheaper to obtain.  As an added benefit, if you can help China with its soot problem, we could see immediate improvements in probably the most visible front of man-made climate change:  in the Arctic.


Perhaps the hardest thing to overcome in reaching a compromise here is the tribalism of modern politics.  I believe this is  a perfectly sensible plan that even those folks who believe man-made global warming is  a total myth ( a group to which I do not belong) could sign up for.  The barrier, though, is tribal.  I consider myself to be pretty free of team politics but my first reaction when thinking about this kind of plan was, "What?  We can't let those guys win.  They are totally full of sh*t.  They are threatening to throw me in jail for my opinions."

It was at this point I was reminded of a customer service story at my company.  I had a customer who was upset call me, and I ended up giving them a full-refund and a certificate to come back and visit us in the future.  I actually suspected there was more to the story, but I didn't want a bad review.  The customer was happy, but my local manager was not.  She called me and said, "That was a bad customer!  He was lying to you.  How can you let him win like that?"   Does this sound familiar?  I think we fall into this trap all the time in modern politics, worried more about preventing the other team from winning than about doing the right thing.

Warren Meyer Speaking in LA on Lukewarmer Climate Position on Wednesday, February 24 -- Come See Me!

I am speaking on Wednesday night at the Athenaeum at Claremont-McKenna College near Pomona on Wednesday, February 24.  It is open to the public and is free.  Come by a say hi if you are in the area.  You can just walk in to the presentation which begins at 6:45 but if you want to attend the pre-dinner at 5:30, there is a $20 charge and you need to reserve a spot by calling  909-621-8244.

I really hope if you are in the LA area you will come by.  The presentation is about 45 minutes plus a Q&A afterwards.


Coyote Climate Talk in LA Area This Week

I am speaking on Wednesday night at the Athenaeum at Claremont-McKenna College near Pomona on Wednesday, February 24.  I believe it is open to the public and is free but requires you to call ahead and reserve a spot.  Come by a say hi if you are in the area.

Coyote on the Real Clear Radio Hour

Bill Frezza interviewed me for his show the other day.  I felt it was not one of my better performances but he says he is a wizard of editing so we will see.  Anyway, I am actually sharing the show with Coyote-favorite Dr. Richard Lindzen, so at least that half of the show should be worth your time.  Here are the details:

Tune in Saturday, February 13th to RealClear Radio Hour with Bill Frezza with guests Richard Lindzen and Warren Meyer.

You can listen live on Bloomberg’s Boston iHeartRadio or Bloomberg’s San Francisco iHeartRadioSaturdays at 10a PT/ 1p ET, 4p PT/ 7p ET or Sundays at 1a PT/ 4a ET.

Government Science Monopoly

Richard Lindzen, atmospheric physicist, MIT professor emeritus, and lead author of the “Physical Climate Processes and Feedbacks” chapter of the 2001 Intergovernmental Panel on Climate Change report, attributes climate hype to politics, money, and propaganda. Lindzen particularly takes issue with the “97% consensus” claim that is being used to stifle debate and demonize skeptics.

Rescuing Public Parks

Warren Meyer, founder and president of Recreation Resource Management, shares how he has successfully managed public parks for nearly 25 years. Meyer advocates for whole park concessions—privatized management of public parks—to save them from closure and agency mismanagement.

If you can't tune in live - download the as-aired shows from iTunes or listen to podcasts with additional content on SoundCloud or YouTube


The weekly one-hour program airs:

WXKS 1200 and WJMN 94.5F in Boston Saturdays 1p & 7p & Sundays 4a ET,

KNEW 960 & KOSF 103.7 in San Francisco Saturdays 10a & 4p & Sundays 1a PT,

1030 KVOI in Tucson, AZ Saturdays 4a MT,

KSBN 1230 Money Talk in Spokane, WA Saturdays 5a PT,

Cities 92.9FM WRPW in Bloomington, IL Saturdays 7a CT,

1590 WSMN in Nashua, NH Saturdays 12p ET,

KATE 1450AM in Alberta Lea, MN Saturdays 1p CT,

1330 WEBY in Pensacola, FL Saturdays 3p CT,

The Patriot, KRMR 105.7FM in Hays, KS Sundays 3p CT,

The Patriot, KNNS 1510AM in Larned, KS Sundays 3p CT,

KVOW 1450 in Riverton, WY Sundays 3p MT, and

WROM Radio in Detroit, MI Mondays 8p ET

US Temperature Trends, In Context

There was some debate a while back around about a temperature chart some Conservative groups were passing around.

Obviously, on this scale, global warming does not look too scary.  The question is, is this scale at all relevant?  I could re-scale the 1929 stock market drop to a chart that goes from Dow 0 to, say, Dow 100,000 and the drop would hardly be noticeable.  That re-scaling wouldn't change the fact that the 1929 stock market crash was incredibly meaningful and had large impacts on the economy.  Kevin Drum wrote about the temperature chart above,

This is so phenomenally stupid that I figured it had to be a joke of some kind.

Mother Jones has banned me from commenting on Drum's site, so I could not participate in the conversation over this chart.  But I thought about it for a while, and I think the chart's author perhaps has a point but pulled it off poorly.  I am going to take another shot at it.

First, I always show the historic temperature anomaly on the zoomed in scale that you are used to seeing, e.g.  (as usual, click to enlarge)

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The problem with this chart is that it is utterly without context just as much as the previous chart.  Is 0.8C a lot or a little?  Going back to our stock market analogy, it's a bit like showing the recent daily fluctuations of the Dow on a scale from 16,300 to 16,350.  The variations will look huge, much larger than either their percentage variation or their meaningfulness to all but the most panicky investors.

So I have started including the chart below as well.  Note that it is in Fahrenheit (vs. the anomaly chart above in Celsius) because US audiences have a better intuition for Fahrenheit, and is only for the US vs. the global chart above.  It shows the range of variation in US monthly averages, with the orange being the monthly average daily maximum temperature across the US, the dark blue showing the monthly average daily minimum temperature, and the green the monthly mean.  The dotted line is the long-term linear trend

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Note that these are the US averages -- the full range of daily maximums and minimums for the US as a whole would be wider and the full range of individual location temperatures would be wider still.   A couple of observations:

  • It is always dangerous to eyeball charts, but you should be able to see what is well known to climate scientists (and not just some skeptic fever dream) -- that much of the increase over the last 30 years (and even 100 years) of average temperatures has come not from higher daytime highs but from higher nighttime minimum temperatures.  This is one reason skeptics often roll their eyes as attribution of 15 degree summer daytime record heat waves to global warming, since the majority of the global warming signal can actually be found with winter and nighttime temperatures.
  • The other reason skeptics roll their eyes at attribution of 15 degree heat waves to 1 degree long term trends is that this one degree trend is trivial compared to the natural variation found in intra-day temperatures, between seasons, or even across years.  It is for this context that I think this view of temperature trends is useful as a supplement to traditional anomaly charts (in my standard presentation, I show this chart scale once and the standard anomaly chart scale further up about 30 times, so that utility has limits).

Revisiting James Hanson's 1988 Global Warming Forecast to Congress

(Cross-posted from Climate Skeptic)

I want to briefly revisit Hansen's 1998 Congressional forecast.  Yes, I and many others have churned over this ground many times, but I think I now have a better approach.   The typical approach has been to overlay some actual temperature data set on top of Hansen's forecast (e.g. here).  The problem is that with revisions to all of these data sets, particularly the GISS reset in 1999, none of these data sets match what Hansen was using at the time.  So we often get into arguments on where the forecast and actuals should be centered, etc.

This might be a better approach.  First, let's start with Hansen's forecast chart (click to enlarge).

hansen forecast

Folks have argued for years over which CO2 scenario best matches history.  I would argue it is somewhere between A and B, but you will see in a moment that it almost does not matter.    It turns out that both A and B have nearly the same regressed slope.

The approach I took this time was not to worry about matching exact starting points or reconciling difference anomaly base periods.  I merely took the slope of the A and B forecasts and compared it to the slope over the last 30 years of a couple of different temeprature databases (Hadley CRUT4 and the UAH v6 satellite data).

The only real issue is the start year.  The analysis is not very sensitive to the year, but I tried to find a logical start.  Hansen's chart is frustrating because his forecasts never converge exactly, even 20 years in the past.  However, they are nearly identical in 1986, a logical base year if Hansen was giving the speech in 1988, so I started there.  I didn't do anything fancy on the trend lines, just let Excel calculate the least squares regression.  This is what we get (as usual, click to enlarge).

click to enlarge

I think that tells the tale  pretty clearly.   Versus the gold standard surface temperature measurement (vs. Hansen's thumb-on-the-scale GISS) his forecast was 2x too high.  Versus the satellite measurements it was 3x too high.

The least squares regression approach probably under-estimates that A scenario growth rate, but that is OK, that just makes the conclusion more robust.

By the way, I owe someone a thanks for the digitized numbers behind Hansen's chart but it has been so many years since I downloaded them I honestly forgot who they came from.

Dear Conservatives: This Is Why We Hate All Your Civil Rights Restrictions in the Name of Fighting Terror

Because about 5 seconds after they are passed, government officials are scheming to use the laws against non-terrorists to protect themselves from criticism.

Twenty-four environmental activists have been placed under house arrest ahead of the Paris climate summit, using France’s state of emergency laws. Two of them slammed an attack on civil liberties in an interview with FRANCE 24....

The officers handed Amélie a restraining order informing her that she can no longer leave Rennes, is required to register three times a day at the local police station, and must stay at home between 8pm and 6am.

The order ends on December 12, the day the Paris climate summit draws to a close....

Citing the heightened terrorist threat, French authorities have issued a blanket ban on demonstrations – including all rallies planned to coincide with the climate summit, which Hollande is due to formally open on Monday.

This justification is about as lame as them come:

AFP news agency has had access to the restraining notices. It says they point to the “threat to public order” posed by radical campaigners, noting that security forces “must not be distracted from the task of combating the terrorist threat”.

Note that the police had absolutely no evidence that these folks were planning any violence, or even that they were planning any particular sort of protest.  This was a classic "round up the usual suspects" dragnet of anyone who had made a name for themselves protesting at green causes in the past.

Postscript:  Yes, I know that these protesters and I would have very little common ground on environmental issues.  So what?  There is nothing more important than supporting the civil rights of those with whom one disagrees.

And yes, I do have the sneaking suspicion that many of the very same people caught up in this dragnet would cheer if I and other skeptics were similarly rounded up for our speech by the government.  But that is exactly the point.  There are people who, if in power, would like to have me rounded up.  So it is important to stand firm against any precedent allowing the government to have these powers.  Else the only thing standing between me and jail is a single election.

Update:  Think that last bit is overly dramatic?  Think again.  I can guarantee you that you have some characteristic or belief that would cause someone in the world today, and probably many people, to want to put you up against the wall if they had the power to do so.  As proof, see:  all of history.

The New Rich -- Living the High Life Through Your Non-Profit

Several months ago, a lot of folks where shocked to find that the Clinton Foundation only spent $9 million in direct aid out of a total budget of $150 million, with the rest going to salaries and bonuses and luxury travel for family and friends and other members of the Clinton posse.

None of this surprised me.  From my time at Ivy League schools, I know any number of kids from rich families that work for some sort of trust or non-profit that has nominally charitable goals, but most of whose budget seems to go to lavish parties, first-class travel, and sinecures for various wealthy family scions.

But this week comes a story from the climate world that demonstrates that making a fortune from your non-profit is not just for the old money any more -- it appears to be a great way for activists to build new fortunes.

The story starts with the abhorrent letter by 20 university professors urging President Obama to use the RICO statute (usually thought of as a tool to fight organized crime) to jail people who disagree with them in a scientific debate.  The letter was authored by Jagadish Shukla of George Mason University, and seems to take the position that all climate skeptics are part of an organized coordinated gang that are actively promoting ideas they know to be wrong solely for financial enrichment. (I will give the near-universal skeptic reply to this:  "So where is my Exxon check?!"

Anyway, a couple of folks, including Roger Pielke, Jr. and Steve McIntyre, both folks who get accused of being oil industry funded but who in fact get little or no funding from any such source, wondered where  Shukla's funding comes from.   Shukla gets what looks like a very generous salary from George Mason University of $314,000 a year.  Power to him on that score.  However, the more interesting part is where he makes the rest of his money, because it turns out his university salary is well under half his total income.  The "non-profits" he controls pays him, his family, and his friends over $800,000 a year in compensation, all paid out of government grants that supposedly are to support science.

A number of years ago Shukla created a couple of non-profits called the Institute for Global Environment and Security (IGES) and the Center for Ocean Land Atmosphere Interactions (COLA).  Both were founded by Shukla and are essentially controlled by him, though both now have some sort of institutional relationship with George Mason University as well.  Steve McIntyre has the whole story in its various details.

COLA and IGES both seem to have gotten most of their revenues from NSF, NASA, and NOAA grants.    Over the years, the IGES appears to have collected over $75 million in grants.  As an aside, this single set of grants to one tiny, you-never-even-heard-of-it climate non-profit is very likely way higher than the cumulative sum total of all money ever paid to skeptics.   I have always thought that warmists freaking out over the trivial sums of money going to skeptics is a bit like a football coach who is winning 97-0 freaking out in anger over the other team finally picking up a first down.

Apparently a LOT of this non-profit grant money ends up in the Shukla family bank accounts.

In 2001, the earliest year thus far publicly available, in 2001, in addition to his university salary (not yet available, but presumably about $125,000), Shukla and his wife received a further $214,496  in compensation from IGES (Shukla -$128,796; Anne Shukla – $85,700).  Their combined compensation from IGES doubled over the next two years to approximately $400,000 (additional to Shukla’s university salary of say $130,000), for combined compensation of about $530,000 by 2004.

Shukla’s university salary increased dramatically over the decade reaching $250,866 by 2013 and $314,000 by 2014.  (In this latter year, Shukla was paid much more than Ed Wegman, a George Mason professor of similar seniority). Meanwhile, despite the apparent transition of IGES to George Mason, the income of the Shuklas from IGES continued to increase, reaching $547,000 by 2013.

Grant records are a real mess but it looks like from George Mason University press releases that IGES and its successor recently got a $10 million five-year grant, or $2 million a year from the government.  Of that money:

  • approximately $550,000 a year goes to Shukla and his wife as salaries
  • some amount, perhaps $90,000 a year, goes to Shukla's daughter as salary
  • $171,000 a year goes as salary to James Kinter, an associate of Shukla at George Mason
  • An unknown amount goes for Shukla's expenses, for example travel.  When was the last time you ever heard of a climate conference, or any NGO conference, being held at, say, the Dallas-Ft Worth Airport Marriott?  No, because these conferences are really meant as paid vacation opportunities as taxpayer expense for non-profit executives.

I don't think it would be too much of a stretch, if one includes travel and personal expenses paid, that half the government grants to this non-profit are going to support the lifestyle of Shukla and his friends and family.  Note this is not money for Shukla's research or lab, this is money paid to him personally.

Progressives always like to point out examples of corruption in for-profit companies, and certainly those exist.  But there are numerous market and legal checks that bring accountability for such corruption.  But nothing of the sort exists in the non-profit world.  Not only are there few accountability mechanisms, but most of these non-profits are very good at using their stated good intentions as a shield from scrutiny -- "How can you accuse us of corruption, we are doing such important work!"

Postscript:  Oddly, another form of this non-profit scam exists in my industry.  As a reminder, my company privately operates public recreation areas.  Several folks have tried to set up what I call for-profit non-profits.  An individual will create a non-profit, and then pay themselves some salary that is equal to or even greater than the profits they would get as an owner.  They are not avoiding taxes -- they still have to pay taxes on that salary just like I have to pay taxes (at the same individual tax rates) on my pass-through profits.

What they are seeking are two advantages:

  • They are hoping to avoid some expensive labor law.  In most cases, these folks over-estimate how much a non-profit shell shelters them from labor law, but there are certain regulations (like the new regulations by the Obama Administration that force junior managers to be paid by the hour rather than be salaried) that do apply differently or not at all to a non-profit.
  • They are seeking to take advantage of a bias among many government employees, specifically that these government employees are skeptical of, or even despise, for-profit private enterprise.  As a result, when seeking to outsource certain operations on public lands, some individual decision-makers in government will have a preference for giving the contract to a nominal non-profit.   In California, there is even legislation that gives this bias a force of law, opening certain government contracting opportunities only to non-profits and not for-profits.

The latter can have hilarious results.  There is one non-profit I know of that is a total dodge, but the "owner" is really good at piously talking about his organization being "cleaner" because it is a non-profit, while all the while paying himself a salary higher than my last year's profits.

These 20 Scientists Want to Make it A Crime to Disagree with Them

I think it is important to publicize these names far and wide:

  • Jagadish Shukla, George Mason University, Fairfax, VA
  • Edward Maibach, George Mason University, Fairfax, VA
  • Paul Dirmeyer, George Mason University, Fairfax, VA
  • Barry Klinger, George Mason University, Fairfax, VA
  • Paul Schopf, George Mason University, Fairfax, VA
  • David Straus, George Mason University, Fairfax, VA
  • Edward Sarachik, University of Washington, Seattle, WA
  • Michael Wallace, University of Washington, Seattle, WA
  • Alan Robock, Rutgers University, New Brunswick, NJ
  • Eugenia Kalnay, University of Maryland, College Park, MD
  • William Lau, University of Maryland, College Park, MD
  • Kevin Trenberth, National Center for Atmospheric Research, Boulder, CO
  • T.N. Krishnamurti, Florida State University, Tallahassee, FL
  • Vasu Misra, Florida State University, Tallahassee, FL
  • Ben Kirtman, University of Miami, Miami, FL
  • Robert Dickinson, University of Texas, Austin, TX
  • Michela Biasutti, Earth Institute, Columbia University, New York, NY
  • Mark Cane, Columbia University, New York, NY
  • Lisa Goddard, Earth Institute, Columbia University, New York, NY
  • Alan Betts, Atmospheric Research, Pittsford, VT

These 20 people, who nominally call themselves "scientists", have written a letter to President Obama urging him to use the RICO statute to prosecute people who disagree with them on climate science, essentially putting scientific disagreement in the same status as organized crime.  If they can't win the scientific debate with persuasion, they will win it with guns.  From the letter:

One additional tool – recently proposed by Senator Sheldon Whitehouse – is a RICO (Racketeer Influenced and Corrupt Organizations Act) investigation of corporations and other organizations that have knowingly deceived the American people about the risks of climate change, as a means to forestall America’s response to climate change.

Of course "deceive the American people" is defined by these folks in practice as "disagreeing with us".

Gawker Was Always Vile

Even before the current unpleasantness, Gawker was always vile.  Here is Adam Weinstein in Gawker arguing that people who disagree with him should be jailed.  Incredibly, Weinstein has been held up in certain quarters as a voice of moderation and reasonableness in the current Gawker brouhaha

Those [climate] denialists should face jail. They should face fines. They should face lawsuits from the classes of people whose lives and livelihoods are most threatened by denialist tactics...

'm talking about Rush and his multi-million-dollar ilk in the disinformation business. I'm talking about Americans for Prosperity and the businesses and billionaires who back its obfuscatory propaganda. I'm talking about public persons and organizations and corporations for whom denying a fundamental scientific fact is profitable, who encourage the acceleration of an anti-environment course of unregulated consumption and production that, frankly, will screw my son and your children and whatever progeny they manage to have.

Those malcontents must be punished and stopped.

Deniers will, of course, fuss and stomp and beat their breasts and claim this is persecution, this is a violation of free speech. Of course, they already say that now, when judges force them into doing penance for comparing climate scientists to child-rapist and denial poster-boy Jerry Sandusky.

But First Amendment rights have never been absolute. You still can't yell "fire" in a crowded theater. You shouldn't be able to yell "balderdash" at 10,883 scientific journal articles a year, all saying the same thing: This is a problem, and we should take some preparations for when it becomes a bigger problem.

Incredibly, he makes this plea while arguing that it is wrong "to deny people the tools they need to inform themselves" --  which we will accomplish by throwing one side of the debate in jail?  Really?

I am so sick of this "First Amendment is not absolute" bullshit.  It is absolute when it comes to issues like debating the merit of a scientific conclusion or debating the political implications of scientific research.  It is absolutely absolute.  In sports terms, this is a pop fly hit to second base.  It is no where near the foul lines.   It is so far from the foul lines that people would look askance at an umpire who screamed "fair ball" when the fact was already so patently obvious.

And no: motives, funding sources, and even being demonstrably right or wrong does not affect this absolute First Amendment protection.

Which all leaves an interesting question for Gawker:  Under what First Amendment theory is outing salacious sexual details of private citizens who happen to work for Gawker's competition in order to gain advertising revenue somehow protected but discussing the shortcomings and political consequences of climate forecasts is not?  I think they are both protected, but the former sure looks closer to the foul line than the latter.

A Great Example of How the Media Twists Facts on Climate

First, let's start with the Guardian headline:

Exxon knew of climate change in 1981, email says – but it funded deniers for 27 more years

So now let's look at the email, in full, which is the sole source for the Guardian headline.  I challenge you, no matter how much you squint, to find a basis for the Guardian's statement.  Basically the email says that Exxon knew of the concern about global warming in 1981, but did not necessarily agree with it.  Hardly the tobacco-lawyer cover-up the Guardian is trying to make it sound like.  I will reprint the email in full because I actually think it is a pretty sober view of how good corporations think about these issues, and it accurately reflects the Exxon I knew from 3 years as a mechanical / safety engineer in a refinery.

I will add that you can see the media denial that a lukewarmer position even exists (which I complained about most recently here) in full action in this Guardian article.  Exxon's position as described in the Guardian's source looks pretty close to the lukewarmer position to me -- that man made global warming exists but is being exaggerated.   But to the Guardian, and many others, there is only full-blown acceptance of the most absurd exaggerated climate change forecasts or you are a denier.  Anyway, here is the email in full:

Corporations are interested in environmental impacts only to the extent that they affect profits, either current or future. They may take what appears to be altruistic positions to improve their public image, but the assumption underlying those actions is that they will increase future profits. ExxonMobil is an interesting case in point.

Exxon first got interested in climate change in 1981 because it was seeking to develop the Natuna gas field off Indonesia. This is an immense reserve of natural gas, but it is 70% CO2. That CO2 would have to be separated to make the natural gas usable. Natural gas often contains CO2 and the technology for removing CO2 is well known. In 1981 (and now) the usual practice was to vent the CO2 to the atmosphere. When I first learned about the project in 1989, the projections were that if Natuna were developed and its CO2 vented to the atmosphere, it would be the largest point source of CO2 in the world and account for about 1% of projected global CO2 emissions. I’m sure that it would still be the largest point source of CO2, but since CO2 emissions have grown faster than projected in 1989, it would probably account for a smaller fraction of global CO2 emissions.

The alternative to venting CO2 to the atmosphere is to inject it into ground. This technology was also well known, since the oil industry had been injecting limited quantities of CO2 to enhance oil recovery. There were many questions about whether the CO2 would remain in the ground, some of which have been answered by Statoil’s now almost 20 years of experience injecting CO2 in the North Sea. Statoil did this because the Norwegian government placed a tax on vented CO2. It was cheaper for Statoil to inject CO2 than pay the tax. Of course, Statoil has touted how much CO2 it has prevented from being emitted.

In the 1980s, Exxon needed to understand the potential for concerns about climate change to lead to regulation that would affect Natuna and other potential projects. They were well ahead of the rest of industry in this awareness. Other companies, such as Mobil, only became aware of the issue in 1988, when it first became a political issue. Natural resource companies – oil, coal, minerals – have to make investments that have lifetimes of 50-100 years. Whatever their public stance, internally they make very careful assessments of the potential for regulation, including the scientific basis for those regulations. Exxon NEVER denied the potential for humans to impact the climate system. It did question – legitimately, in my opinion – the validity of some of the science.

Political battles need to personify the enemy. This is why liberals spend so much time vilifying the Koch brothers – who are hardly the only big money supporters of conservative ideas. In climate change, the first villain was a man named Donald Pearlman, who was a lobbyist for Saudi Arabia and Kuwait. (In another life, he was instrumental in getting the U.S. Holocaust Museum funded and built.) Pearlman’s usefulness as a villain ended when he died of lung cancer – he was a heavy smoker to the end.

Then the villain was the Global Climate Coalition (GCC), a trade organization of energy producers and large energy users. I was involved in GCC for a while, unsuccessfully trying to get them to recognize scientific reality. (That effort got me on to the front page of the New York Times, but that’s another story.) Environmental group pressure was successful in putting GCC out of business, but they also lost their villain. They needed one which wouldn’t die and wouldn’t go out of business. Exxon, and after its merger with Mobil ExxonMobil, fit the bill, especially under its former CEO, Lee Raymond, who was vocally opposed to climate change regulation. ExxonMobil’s current CEO, Rex Tillerson, has taken a much softer line, but ExxonMobil has not lost its position as the personification of corporate, and especially climate change, evil. It is the only company mentioned in Alyssa’s e-mail, even though, in my opinion, it is far more ethical that many other large corporations.

Having spent twenty years working for Exxon and ten working for Mobil, I know that much of that ethical behavior comes from a business calculation that it is cheaper in the long run to be ethical than unethical. Safety is the clearest example of this. ExxonMobil knows all too well the cost of poor safety practices. The Exxon Valdez is the most public, but far from the only, example of the high cost of unsafe operations. The value of good environmental practices are more subtle, but a facility that does a good job of controlling emission and waste is a well run facility, that is probably maximizing profit. All major companies will tell you that they are trying to minimize their internal CO2 emissions. Mostly, they are doing this by improving energy efficiency and reducing cost. The same is true for internal recycling, again a practice most companies follow. Its just good engineering.

Matt Ridley: What the Climate Wars Did to Science

I cannot recommend Matt Ridley's new article strongly enough.  It covers a lot of ground be here are a few highlights.

Ridley argues that science generally works (in a manner entirely parallel to how well-functioning commercial markets work) because there are generally incentives to challenge hypotheses.  I would add that if anything, the incentives tend to be balanced more towards challenging conventional wisdom.  If someone puts a stake in the ground and says that A is true, then there is a lot more money and prestige awarded to someone who can prove A is not true than for the thirteenth person to confirm that A is indeed true.

This process breaks, however when political pressures undermine this natural market of ideas and switch the incentives for challenging hypotheses into punishment.

Lysenkoism, a pseudo-biological theory that plants (and people) could be trained to change their heritable natures, helped starve millions and yet persisted for decades in the Soviet Union, reaching its zenith under Nikita Khrushchev. The theory that dietary fat causes obesity and heart disease, based on a couple of terrible studies in the 1950s, became unchallenged orthodoxy and is only now fading slowly.

What these two ideas have in common is that they had political support, which enabled them to monopolise debate. Scientists are just as prone as anybody else to “confirmation bias”, the tendency we all have to seek evidence that supports our favoured hypothesis and dismiss evidence that contradicts it—as if we were counsel for the defence. It’s tosh that scientists always try to disprove their own theories, as they sometimes claim, and nor should they. But they do try to disprove each other’s. Science has always been decentralised, so Professor Smith challenges Professor Jones’s claims, and that’s what keeps science honest.

What went wrong with Lysenko and dietary fat was that in each case a monopoly was established. Lysenko’s opponents were imprisoned or killed. Nina Teicholz’s book  The Big Fat Surprise shows in devastating detail how opponents of Ancel Keys’s dietary fat hypothesis were starved of grants and frozen out of the debate by an intolerant consensus backed by vested interests, echoed and amplified by a docile press....

This is precisely what has happened with the climate debate and it is at risk of damaging the whole reputation of science.

This is one example of the consequences

Look what happened to a butterfly ecologist named Camille Parmesan when she published a paper on “ Climate and Species Range” that blamed climate change for threatening the Edith checkerspot butterfly with extinction in California by driving its range northward. The paper was cited more than 500 times, she was invited to speak at the White House and she was asked to contribute to the IPCC’s third assessment report.

Unfortunately, a distinguished ecologist called Jim Steele found fault with her conclusion: there had been more local extinctions in the southern part of the butterfly’s range due to urban development than in the north, so only the statistical averages moved north, not the butterflies. There was no correlated local change in temperature anyway, and the butterflies have since recovered throughout their range.  When Steele asked Parmesan for her data, she refused. Parmesan’s paper continues to be cited as evidence of climate change. Steele meanwhile is derided as a “denier”. No wonder a highly sceptical ecologist I know is very reluctant to break cover.

He also goes on to lament something that is very familiar to me -- there is a strong argument for the lukewarmer position, but the media will not even achnowledge it exists.  Either you are a full-on believer or you are a denier.

The IPCC actually admits the possibility of lukewarming within its consensus, because it gives a range of possible future temperatures: it thinks the world will be between about 1.5 and four degrees warmer on average by the end of the century. That’s a huge range, from marginally beneficial to terrifyingly harmful, so it is hardly a consensus of danger, and if you look at the “probability density functions” of climate sensitivity, they always cluster towards the lower end.

What is more, in the small print describing the assumptions of the “representative concentration pathways”, it admits that the top of the range will only be reached if sensitivity to carbon dioxide is high (which is doubtful); if world population growth re-accelerates (which is unlikely); if carbon dioxide absorption by the oceans slows down (which is improbable); and if the world economy goes in a very odd direction, giving up gas but increasing coal use tenfold (which is implausible).

But the commentators ignore all these caveats and babble on about warming of “up to” four degrees (or even more), then castigate as a “denier” anybody who says, as I do, the lower end of the scale looks much more likely given the actual data. This is a deliberate tactic. Following what the psychologist Philip Tetlock called the “psychology of taboo”, there has been a systematic and thorough campaign to rule out the middle ground as heretical: not just wrong, but mistaken, immoral and beyond the pale. That’s what the word denier with its deliberate connotations of Holocaust denial is intended to do. For reasons I do not fully understand, journalists have been shamefully happy to go along with this fundamentally religious project.

The whole thing reads like a lukewarmer manifesto.  Honestly, Ridley writes about 1000% better than I do, so rather than my trying to summarize it, go read it.

"Man-Made" Climate Change

Man has almost certainly warmed the world by some tenths of a degree C with his CO2, though much of this warming has hit night-time lows rather than daily highs.  Anyway, while future temperature rise forecasts are often grossly exaggerated by absurdly high assumptions of positive feedback, there is at least a kernel of fact in there that CO2 is likely warming the world somewhat.

However, the popular "science" on climate change is often awful, positing, for example, that hurricanes are being increased by man right in the midst of the longest hurricane drought we have seen in the US for a hundred years.

Inevitably, the recent severe California droughts have been blamed on manmade CO2.  As a hopefully useful adjunct to this debate, I have annotated a recent chart from the San Jose Mercury News on the history of California droughts to reflect the popular global warming / climate change narrative.  You be the judge of the reasonableness:

click to enlarge

LMAO -- My Kid Learns About the Cold

My Arizona-raised, thin-blooded son was convinced that he had no problem with cold weather when he departed for Amherst College several years ago.  That, of course, was based on exposure to cold via a couple of ski trips.  What he likely underestimated was the impact of cold that lasts for like 6 freaking months.

So it was with good-natured parental fondness for my child that I was LMAO when I read this:

Amherst, MA has coldest February in recorded history.  or here if you hit a paywall.

The average temperature in Amherst in the past month was 11.2 degrees, the lowest average monthly temperature since records were first kept in town in 1835. It broke the previous record of 11.6 degrees set in 1934, according to Michael A. Rawlins, an assistant professor in the department of geosciences and manager of the Climate System Research Center at the University of Massachusetts.

As it turns out, I have made a climate presentation in Amherst so I actually have historic temperature charts.  It is a good example of two things:

  1. While Amherst has been warming, it was warming as much or more before 1940 (or before the era of substantial CO2 emissions) as much as after
  2. Much of the recent warming has manifested as increases in daily minimum temperatures, rather in an increase in daily maximum temperatures.  This is as predicted by warming models, but poorly communicated and understood.  Possibly because fewer people would be bent out of shape if they knew that warming translated into warmer nights rather than higher highs in the daytime.

click to enlarge

Wherein I Come Clean to Representative Grijalva

Here is the letter I wrote today (pdf) to Representative Grijalva confessing my climate funding biases.  The image is below.  I feel so much better.


I wrote this in support particularly of Roger Pielke, who has educated a lot of people about climate and is not even really a climate skeptic and who has been pretty upset by this scrutiny.  Call it the "I am Spartacus" strategy.

My earlier post on funding and bias is here.

On Funding and Bias in Climate

I really, really did not want to have to write yet another post on this.  99+% of all climate funding goes to alarmists rather than skeptics.   Greenpeace laments donations of funds to skeptics by Exxon of a million dollars or so and wants to drive out all such funding when Greenpeace and Tides and the US Government are giving literally billions to alarmists.  Despite this staggering imbalance, the only stories you ever see are about the dangers and bias introduced by that measly 1% skeptics get.  I guess that 1% is spent pretty well because it sure seems to have people running in circles declaring the sky is falling.

One would think that at some point the world would wake up and realize that criticizing the funding sources behind an individual does not actually rebut that individual's arguments.

Potential bias introduced by funding sources (or some other influence) are a pointer -- they are an indication there might be a problem warranting deeper examination of the evidence introduced and the methodology of collecting that evidence.  Such potential biases are not themselves evidence, and do nothing to rebut an argument.  A reasonable way to use such biases in an argument would be something like:

I want to begin by noting that Joe may have had a predisposition to his stated conclusion even before he started because of [funding source, political view, whatever].  This means we need to very carefully look at how he got to his conclusion.  And I intend to show you that he made several important errors that should undermine our acceptance of his conclusions.  They are....

Unfortunately, nowadays people like the New York Times and our own Arizona Representative Raul Grijalva seem to feel like the job is done after the first sentence.  They have decided that the best way to refute recent scientific work by a number of climate scientists is to try to show that some of their funding comes from fossil fuel companies.

Beyond the strange implicit assumption that fossil fuel funding would automatically "disprove" a research paper, there is also an assumption that oil company funding is "unclean" while government or non-profit environmental group funding is "clean".  Remember the last time you saw a news story about a climate alarmist's funding?  Yeah, neither do I.

There is no justifiable reason for this asymmetry.  Funding does not potentially introduce bias because it is sourced from for-profit or non-profit entities.  In fact, the motivation of the funding source is virtually irrelevant.  The only relevant questions related to bias are:

  1. Did the funding source demand a certain conclusion at the outset of the study as the price of the funding -- or --
  2. Is there a reasonable expectation that the source would deny future funding if the conclusions of the study don't go their way

My sense is that #1 is rare and that the real issue is #2.

But #2 is ubiquitous.  Sure, if a group of skeptical scientists suddenly started writing papers about 8 degree warming predictions, Chevron is going to be less likely to fund their future research.  But on the flip side if Michael Mann suddenly started saying that future warming will only be a modest 1-2 degrees, do you think that he would continue to get funding from Greenpeace, the Tides Foundation, the WWF, or even from an Obama-run Federal agency?  No way.   There is absolutely no less bias introduced by Chevron funding than from Greenpeace funding, because in each case there can be a reasonable fear by the researcher that future funding would be denied by that source if the "right" answer was not reached.

Postscript & Disclosure of Biases:  I have never received any outside funding for this blog or my climate work.  However, if Chevron were to send me a check for a million dollars, I would probably cash it.  I do own individual shares of ExxonMobil stock as well as shares of the Vanguard S&P500 index fund, which includes equities of a number of energy companies.  I also am a frequent purchaser of gasoline and electricity, as well as a number of other products and services whose prices are tied to energy prices (e.g. air transportation).  As a consumer, I would rather not see the prices of these products rise.  I buy a lot of food, whose price might be improved by longer growing seasons.  My camping company tends to benefit from rising gasoline prices, because rising prices causes people to stay closer to home and camp at the type of places we operate.  It is hard to predict how regional climates will change if overall global temperatures rise, but since many of my campgrounds are summer escapes at high altitude, they would probably benefit somewhat from rising temperatures.  I own a home in Arizona whose value would probably be lessened if the world warmed 2-3 degrees, because it would make winters in the northeast and midwest more bearable and thus hurt Arizona as a location for a winter second home.  Global warming may reduce the life of my dog as we are less likely to walk her when it is over 100 degrees out which makes her less healthy.  I own land in Hawaii that might be more valuable if sea level rises puts it 6-8 inches close to the ocean.  I am planning a vacation to see the tulips bloom in Holland and changes in climate could shift the blooming date and thus cause me to miss the best colors.  Fifteen years from now my daughter would like a June wedding and changes to climate might cause it to rain that day.  My daughter also owns 5 shares of Walt Disney and their earnings might be helped by global warming as nostalgia for cooler weather could greatly increase DVD sales of "Frozen".

Skeptics: Please Relax on the Whole "Greatest Scientific Fraud of All Time" Thing

Climate skeptics are at risk of falling into the same exaggeration-trap as do alarmists.

I have written about the exaggeration of past warming by questionable manual adjustments to temperature records for almost a decade.  So I don't need to be convinced that these adjustments 1) need to be cleaned up and 2) likely exaggerate past warming.

However, this talk of the "Greatest Scientific Fraud of All Time" is just crazy.  If you are interested, I urge you read my piece from the other day for a more balanced view.  Don't stop reading without checking out #4.

These recent articles are making it sound like alarmist scientists are simply adding adjustments to past temperatures for no reason.  But there are many perfectly valid reasons surface temperature measurements have to be manually adjusted.  It is a required part of the process.  Just as the satellite data must be adjusted as well, though for different things.

So we should not be suspicious of adjustments per se.  We should be concerned about them, though, for a number of reasons:

  • In many parts of the world, like in the US, the manual adjustments equal or exceed the measured warming trend.  That means the"signal" we are measuring comes entirely from the adjustments.  That is, to put it lightly, not ideal.
  • The adjustments are extremely poorly documented and impossible for any third party to replicate (one reason the satellite record may be more trustworthy is all the adjustment code for the satellites is open source).
  • The adjustments may have a bias.  After all, most of the people doing the adjustments expect to see a warming trend historically, and so consider lack of such a trend to be an indicator the data is wrong and in need of adjustment.  This is not a conspiracy, but a normal human failing and the reason why the ability to replicate such work is important.
  • The adjustments do seem to be very aggressive in identifying any effects that might have artificially created a cooling trend but lax in finding and correcting effects that might have artificially created a warming trend.  First and foremost, the changing urban heat island effect in growing cities seems to be under-corrected  (Again there is debate on this -- the proprietors of the model believe they have fixed this with a geographic normalizing, correcting biases from nearby thermometers.  I and others believe all they are doing is mathematically smearing the error over a larger geography).

Again, I discussed all the pros and cons here.  If pushed to the wall, I would say perhaps half of the past warming in the surface temperature record is due to undercorrection of warming biases or overcorrection of cooling biases.

Bill Maher, Living in an Echo Chamber

I refuse to assume (contrary to the modern practice) that someone who disagrees with me is either stupid or ill-intentioned or both [OK, I did call people idiots here -- sorry, I was ranting].  Intelligent people of goodwill can disagree with each other, and the world would be a better place if more people embraced that simple notion.

Anyway, I won't blame lack of intelligence or bad motivations for the following statement from Bill Maher.  He seems to be a smart guy who is honestly motivated by what he says motivates him.  But this statement is just so ignorant and provably false that it must be the result of living in a very powerful echo chamber where no voices other than ones that agree with him are allowed.

HBO’s Bill Maher complained that comparing climate change skepticism to vaccine skepticism was unfair to vaccine skeptics before attacking GMOs on Friday’s “Real Time.”

“The analogy that I see all the time is that if you ask any questions [about vaccines], you are the same thing as a global warming denier. I think this is a very bad analogy, because I don’t think all science is alike. I think climate science is rather straightforward because you’re dealing with the earth, it’s a rock…climate scientists, from the very beginning, have pretty much said the same thing, and their predictions have pretty much come true. It’s atmospherics, and it’s geology, and chemistry. That’s not true of the medical industry. I mean, they’ve had to retract a million things because the human body is infinitely more mysterious” he stated.

Climate science is astoundingly complex with thousands or millions of variables interacting chaotically.  Separating cause and effect is a nightmare, because controlled experiments are impossible.  It is stupendously laughable that he could think this task somehow straightforward, or easier than running a double-blind medical study  (By the way, this is one reason for the retractions in medicine vs. climate -- medical studies are straightforward enough they can be easily replicated... or not, and thus retracted.  Proving cause and effect in climate is so hard that studies may be of low quality, but they are also hard to absolutely disprove).

It is funny of course that he would also say that all of climate scientists predictions have come true.  Pretty much none have come true.  They expected  rapidly rising temperatures and they have in fact risen only modestly, if at all, over the last 20 years or so.  They expected more hurricanes and there have been fewer.  They called for more tornadoes and there have been fewer.  The only reason any have been right at all is that climate scientists have separately forecasts opposite occurrences (e.g. more snow / less snow) so someone has to be right, though this state of affairs hardly argues for the certainty of climate predictions.

By the way, the assumption that Bill Maher is an intelligent person of goodwill who simply disagrees with me on things like climate and vaccines and GMO's is apparently not one he is willing to make himself about his critics.  e.g.:

Weekly Standard Senior Writer John McCormack then pointed out that there are legitimate scientists, such as Dr. Richard Lindzen, who are skeptical of man-made climate change theories, but that there were no serious vaccine-skeptic professors, to which Maher rebutted “the ones who are skeptics [on climate change], usually are paid off by the oil industry.”

I will point out to you that the Left's positions on climate, vaccines, and GMO's have many things in common, as I wrote in a long article on evaluating risks here.

Adjusting the Temperature Records

I have been getting inquiries from folks asking me what I think about stories like this one, where Paul Homewood has been looking at the manual adjustments to raw temperature data and finding that the adjustments actually reverse the trends from cooling to warming.  Here is an example of the comparisons he did:

Raw, before adjustments;



After manual adjustments



I actually wrote about this topic a few months back, and rather than rewrite the post I will excerpt it below:

I believe that there is both wheat and chaff in this claim [that manual temperature adjustments are exaggerating past warming], and I would like to try to separate the two as best I can.  I don't have time to write a well-organized article, so here is just a list of thoughts

  1. At some level it is surprising that this is suddenly news.  Skeptics have criticized the adjustments in the surface temperature database for years.
  2. There is certainly a signal to noise ratio issue here that mainstream climate scientists have always seemed insufficiently concerned about.  For example, the raw data for US temperatures is mostly flat, such that the manual adjustments to the temperature data set are about equal in magnitude to the total warming signal.  When the entire signal one is trying to measure is equal to the manual adjustments one is making to measurements, it probably makes sense to put a LOT of scrutiny on the adjustments.  (This is a post from 7 years ago discussing these adjustments.  Note that these adjustments are less than current ones in the data base as they have been increased, though I cannot find a similar chart any more from the NOAA discussing the adjustments)
  3. The NOAA HAS made adjustments to US temperature data over the last few years that has increased the apparent warming trend.  These changes in adjustments have not been well-explained.  In fact, they have not really be explained at all, and have only been detected by skeptics who happened to archive old NOAA charts and created comparisons like the one below.  Here is the before and after animation (pre-2000 NOAA US temperature history vs. post-2000).  History has been cooled and modern temperatures have been warmed from where they were being shown previously by the NOAA.  This does not mean the current version  is wrong, but since the entire US warming signal was effectively created by these changes, it is not unreasonable to act for a detailed reconciliation (particularly when those folks preparing the chart all believe that temperatures are going up, so would be predisposed to treating a flat temperature chart like the earlier version as wrong and in need of correction. 1998changesannotated
  4. However, manual adjustments are not, as some skeptics seem to argue, wrong or biased in all cases.  There are real reasons for manual adjustments to data -- for example, if GPS signal data was not adjusted for relativistic effects, the position data would quickly get out of whack.  In the case of temperature data:
    • Data is adjusted for shifts in the start/end time for a day of measurement away from local midnight (ie if you average 24 hours starting and stopping at noon).  This is called Time of Observation or TOBS.  When I first encountered this, I was just sure it had to be BS.  For a month of data, you are only shifting the data set by 12 hours or about 1/60 of the month.  Fortunately for my self-respect, before I embarrassed myself I created a spreadsheet to monte carlo some temperature data and play around with this issue.  I convinced myself the Time of Observation adjustment is valid in theory, though I have no way to validate its magnitude  (one of the problems with all of these adjustments is that NOAA and other data authorities do not release the source code or raw data to show how they come up with these adjustments).   I do think it is valid in science to question a finding, even without proof that it is wrong, when the authors of the finding refuse to share replication data.  Steven Goddard, by the way, believes time of observation adjustments are exaggerated and do not follow NOAA's own specification.
    • Stations move over time.  A simple example is if it is on the roof of a building and that building is demolished, it has to move somewhere else.  In an extreme example the station might move to a new altitude or a slightly different micro-climate.  There are adjustments in the data base for these sort of changes.  Skeptics have occasionally challenged these, but I have no reason to believe that the authors are not using best efforts to correct for these effects (though again the authors of these adjustments bring criticism on themselves for not sharing replication data).
    • The technology the station uses for measurement changes (e.g. thermometers to electronic devices, one type of electronic device to another, etc.)   These measurement technologies sometimes have known biases.  Correcting for such biases is perfectly reasonable  (though a frustrated skeptic could argue that the government is diligent in correcting for new cooling biases but seldom corrects for warming biases, such as in the switch from bucket to water intake measurement of sea surface temperatures).
    • Even if the temperature station does not move, the location can degrade.  The clearest example is a measurement point that once was in the country but has been engulfed by development  (here is one example -- this at one time was the USHCN measurement point with the most warming since 1900, but it was located in an open field in 1900 and ended up in an asphalt parking lot in the middle of Tucson.)   Since urban heat islands can add as much as 10 degrees F to nighttime temperatures, this can create a warming signal over time that is related to a particular location, and not the climate as a whole.  The effect is undeniable -- my son easily measured it in a science fair project.  The effect it has on temperature measurement is hotly debated between warmists and skeptics.  Al Gore originally argued that there was no bias because all measurement points were in parks, which led Anthony Watts to pursue the surface station project where every USHCN station was photographed and documented.  The net result was that most of the sites were pretty poor.  Whatever the case, there is almost no correction in the official measurement numbers for urban heat island effects, and in fact last time I looked at it the adjustment went the other way, implying urban heat islands have become less of an issue since 1930.  The folks who put together the indexes argue that they have smoothing algorithms that find and remove these biases.  Skeptics argue that they just smear the bias around over multiple stations.  The debate continues.
  5. Overall, many mainstream skeptics believe that actual surface warming in the US and the world has been about half what is shown in traditional indices, an amount that is then exaggerated by poorly crafted adjustments and uncorrected heat island effects.  But note that almost no skeptic I know believes that the Earth has not actually warmed over the last 100 years.  Further, warming since about 1980 is hard to deny because we have a second, independent way to measure global temperatures in satellites.  These devices may have their own issues, but they are not subject to urban heat biases or location biases and further actually measure most of the Earth's surface, rather than just individual points that are sometimes scores or hundreds of miles apart.  This independent method of measurement has shown undoubted warming since 1979, though not since the late 1990's.
  6. As is usual in such debates, I find words like "fabrication", "lies",  and "myth" to be less than helpful.  People can be totally wrong, and refuse to confront their biases, without being evil or nefarious.

To these I will add a #7:  The notion that satellite results are somehow pure and unadjusted is just plain wrong.  The satellite data set takes a lot of mathematical effort to get right, something that Roy Spencer who does this work (and is considered in the skeptic camp) will be the first to tell you.  Satellites have to be adjusted for different things.  They have advantages over ground measurement because they cover most all the Earth, they are not subject to urban heat biases, and bring some technological consistency to the measurement.  However, the satellites used are constantly dieing off and being replaced, orbits decay and change, and thus times of observation of different parts of the globe change [to their credit, the satellite folks release all their source code for correcting these things].   I have become convinced the satellites, net of all the issues with both technologies, provide a better estimate but neither are perfect.

The 2014 Temperature Record No One Is Talking About

Depending on what temperature data set you look at **, or on your trust in various manual adjustments in these data sets ***, 2014 may have beaten the previous world temperature record by 0.02C.  Interestingly, the 0.02C rise over the prior record set four years ago would imply (using only these two data points which warmists seem to want to focus on) a temperature increase of 0.5C per century, a few tenths below my prediction but an order of magnitude below the alarmists' predictions for future trends.

Anyway, whether there was an absolute record or not, there was almost certainly a different temperature record set -- the highest divergence to date in the modern measured temperatures from what the computer models predicted.  The temperature increase for the past 5 years was a full 0.17C less than predicted, the largest gap yet for the models in forward-prediction mode (as opposed to when they are used to backcast history).


** There are four or five or more data sets, depending on how you count them.   There are 2 major satellite data sets and 2-3 ground based data sets.  The GISS ground data set generally gives the largest warming trends, while the satellite data sets give the least, but all show some warming over the last 30 or so years (though most of this warming was before 1999).

*** The data sets are all full of manual adjustments of various sorts.  All of these are necessary.  For surface stations, the measurement points move and change technology.  For the satellites, orbits and instruments shift over time.  The worrisome feature of all these adjustments is that they are large as compared to the underlying warming signal being measured, so small changes in the adjustments can lead to large changes in the apparent trend.  Skeptics often charge that the proprietors of land data sets are aggressive about including adjustments that increase the apparent trend but reluctant to add similar adjustments (eg for urban heat islands) that might reduce the trend.  As a result, most of the manual adjustments increase the trend.  There is actually little warming trend in the raw data, and it only shows up after the adjustments.  It may be total coincidence, but the database run by the most ardent warmist is the GISS and it has the highest trend.   The database run by the most skeptical is the UAH satellite database and it shows the smallest trend.  Hmm.

California Drought Update -- Not Even Close to Worst Drought Ever

There is little trend evidence anywhere that climate is getting -- pick the world -- weirder, more extreme, out of whack, whatever.  In particular, name any severe weather category you can imagine, and actual data in trend charts likely will not show any recent trend.

The reasons the average person on the street will swear you are a crazy denier for pointing such a thing out to them is that the media bombards them with news of nearly every 2+ sigma weather event, calling most of these relatively normal episodes as "the worst ever".

A great example is the California drought.  Here is the rolling average 5-year precipitation chart for California.  Find the worst drought "ever".


I know no one trusts anyone else's data in public debates, but you can make these charts yourself at the NOAA site, just go here:  The one record set was that 2013 had the lowest measured CA precipitation in the last century plus, so that was indeed a record bad year, but droughts are typically made up of multiple years of below average precipitation and by that measure the recent CA drought is the fourth or fifth worst.

By the way, Paul Homewood points out something that even surprised me and I try not to be susceptible to the mindless media bad news stampeded:  California rainfall this year was close to normal.  And, as you can see, there is pretty much no trend over the last century plus in California rainfall:



As discussed previously, let's add the proviso that rainfall is not necessarily the best metric of drought.  The Palmer drought index looks at moisture in soil and takes into account other factors like temperature and evaporation, and by that metric this CA drought is closer to the worst of the century, though certainly not what one would call unprecedented.  Also, there is a worsening trend in the Palmer data.



Update:  By the way, the fact that two measures of drought give us two different answers on the relative severity of the drought and on the trend in droughts is typical.   It makes a mockery of the pretense to certainty on these topics in the media.  Fortunately, I am not so invested in the whole thing that I can't include data that doesn't support my thesis.

What is Normal?

I titled my very first climate video "What is Normal," alluding to the fact that climate doomsayers argue that we have shifted aspects of the climate (temperature, hurricanes, etc.) from "normal" without us even having enough historical perspective to say what "normal" is.

A more sophisticated way to restate this same point would be to say that natural phenomenon tend to show various periodicities, and without observing nature through the whole of these cycles, it is easy to mistake short term cyclical variations for long-term trends.

A paper in the journal Water Resources Research makes just this point using over 200 years of precipitation data:

We analyze long-term fluctuations of rainfall extremes in 268 years of daily observations (Padova, Italy, 1725-2006), to our knowledge the longest existing instrumental time series of its kind. We identify multidecadal oscillations in extremes estimated by fitting the GEV distribution, with approximate periodicities of about 17-21 years, 30-38 years, 49-68 years, 85-94 years, and 145-172 years. The amplitudes of these oscillations far exceed the changes associated with the observed trend in intensity. This finding implies that, even if climatic trends are absent or negligible, rainfall and its extremes exhibit an apparent non-stationarity if analyzed over time intervals shorter than the longest periodicity in the data (about 170 years for the case analyzed here). These results suggest that, because long-term periodicities may likely be present elsewhere, in the absence of observational time series with length comparable to such periodicities (possibly exceeding one century), past observations cannot be considered to be representative of future extremes. We also find that observed fluctuations in extreme events in Padova are linked to the North Atlantic Oscillation: increases in the NAO Index are on average associated with an intensification of daily extreme rainfall events. This link with the NAO global pattern is highly suggestive of implications of general relevance: long-term fluctuations in rainfall extremes connected with large-scale oscillating atmospheric patterns are likely to be widely present, and undermine the very basic idea of using a single stationary distribution to infer future extremes from past observations.

Trying to work with data series that are too short is simply a fact of life -- everyone in climate would love a 1000-year detailed data set, but we don't have it.  We use what we have, but it is important to understand the limitations.  There is less excuse for the media that likes to use single data points, e.g. one storm, to "prove" long term climate trends.

A good example of why this is relevant is the global temperature trend.  This chart is a year or so old and has not been updated in that time, but it shows the global temperature trend using the most popular surface temperature data set.  The global warming movement really got fired up around 1998, at the end of the twenty year temperature trend circled in red.

click to enlarge


They then took the trends from these 20 years and extrapolated them into the future:

click to enlarge

But what if that 20 years was merely the upward leg of a 40-60 year cyclic variation?  Ignoring the cyclic functions would cause one to overestimate the long term trend.  This is exactly what climate models do, ignoring important cyclic functions like the AMO and PDO.

In fact, you can get a very good fit with actual temperature by modeling them as three functions:  A 63-year sine wave, a 0.4C per century long-term linear trend  (e.g. recovery from the little ice age) and a new trend starting in 1945 of an additional 0.35C, possibly from manmade CO2.Slide52

In this case, a long-term trend still appears to exist but it is exaggerated by only trying to measure it in the upward part of the cycle (e.g. from 1978-1998).