Some Surprisingly Persistent Climate Denial Arguments

Some Surprisingly Persistent Climate Denial Arguments

Recently I have encountered what I consider to be surprising doubts about the reality of anthropogenic climate change.  Perhaps this is a sign of the times, where authorities such as scientists are no longer trusted and assumed to be operating with some kind of political agenda.  What are we to believe in the face of apparent disagreement over the issue?

The mainstream view of climate science is that mankind is causing the warming of our atmosphere through burning hydrocarbons, and that unless some action is taken to limit the temperature increase to 1.5°, we are on course for serious and unpredictable effects on humanity and other life on earth.  The aim of this article is to explore a few of the ideas which have gained currency and are used to dispute the mainstream view.

Here is a list of some climate objections which I have heard expressed of late:

  1. The climate varies due to natural causes (and life has survived just fine)
  2. The science is not settled
  3. CO2 is not a pollutant (it makes plants grow, so more is better)
  4. Correlation is not causation
  5. The economy will collapse if we stop using oil and gas
  6. Solar and wind are too intermittent to meet energy needs

The climate varies due to natural causes (and life has survived just fine)

This is true.  Over geological timescales there is huge variation in climate.  The causes are manifold.

Over millions of years, changes in the position of continents have a strong effect on climate.  There are causes related to the earth’s motion such as variation in the tilt of its spin axis, precession of the spin axis and the eccentricity of its orbit around the sun.  These three can be lumped together under something called Milankovitch theory.  The effect operates on a scale measured in 10s to 100s of thousand years.  Events like volcanic eruptions can occur and generally have a cooling effect which may last for months or years.  It is also true that CO2 concentrations have varied widely.  High CO2 concentrations have been associated with high temperatures over geological timescales.  It is also true that earth has been much hotter in the past and life did just fine.  In recent history (i.e. the last few 100,000 years) earth has been much colder than present, since we are currently in an interglacial period.   If all we care about is that life will survive, then there is probably little cause for concern.  Global warming will not wipe life out.   However, this does not mean that all species will survive just fine.  Climate change has been responsible for some of the major extinction events in geological history.  More relevantly, it also is no guarantee that conditions which are comfortable for human civilization will persist.  Furthermore, geologically speaking CO2 concentrations change over periods measured in thousands of years, not decades.  It is the speed with which CO2 is being cranked up by human activity which is a cause for concern.

The science is not settled

The claim that the science is not settled, is usually based on the acknowledged uncertainties around modelling a complex system such as the climate.  It is important to distinguish between uncertainties related to the fact of climate change and the details as to how it will manifest.  Climate prediction is fraught because of non-linear responses and feedback.  For example, water vapour is a stronger contributor to climate change than CO2, and one criticism I have come across is that the effect of warming on water vapour and cloud formation is poorly understood.  In general terms, we know that it can be a negative feedback (i.e. reduce the effect of warming) via clouds which may reflect sunlight back to space, but it can also serve as a positive feedback (i.e. amplify the effect of warming) by trapping energy within the atmosphere.

The presence of feedbacks such as water vapour does not lead logically to a climate change denial position however: the fact is that the feedback effects could potentially make climate change more extreme, rather than less.   Meanwhile, ongoing measurements are by and large confirming that the models do a reasonable job of prediction.  This suggests the feedback effects though not fully understood are well enough understood to make climate models useful as input to climate policy.

CO2 is not a pollutant (it makes plants grow, so more is better)

This strawman argument attributes those who are concerned about climate change with saying “CO2 is polluting our atmosphere”, as if it was similar to smog.  It is easy to ridicule such eco fanatics, pointing out that life depends on CO2, since photosynthesis requires it and so on!  In fact, without the blanked of CO2 (and other greenhouse gases) which our atmosphere already contains, the average surface temperature would be -18C and life would be impossible.  Does the fact that some of a thing is good always mean that more of it is better?  No, obviously not.

We can agree, CO2 is not a pollutant in the conventional sense, harming life directly: scientists are not suggesting that it is.  However, the atmospheric concentration matters.  The earth is warming due to additional CO2 generated by human activity, taking place over a relatively short time period – rising from under 350ppm to over 400ppm during the last 50 years, as seen in the Keeling Curve.  This rapid increase is harmful to some plant and animal species, and very likely to human civilization.

Correlation is not Causation

This argument is all about the relationship between CO2 levels and temperature.  It goes like this: “OK it is true that over geological time there is a correlation between CO2 levels and temperature indicators.  But, so what?  This doesn’t prove that CO2 causes temperature change, it could just as easily be the reverse”.

If we had nothing to go on except the fact that two variables appear to have correlation this argument would hold (some) water.  But this is not the case.  We have a clear physical basis for the expectation that CO2 should cause temperature increases, due to the trapping of infrared radiation.  In fact, the effect goes both ways – a temperature increase also causes the release of CO2 from the oceans, thus creating a positive (reinforcing) feedback effect.

It is true that ice core measurements covering the last 400,000 years appear to indicate that the net release of CO2 lags the increase in temperature.  In these long timescale observations, the initial temperature increase is known to be caused by changes in the earth’s orbit.  However, the total effect was then amplified by the resulting release of CO2 into the atmosphere.  The orbital effect is also well understood and is not sufficient on its own to explain observed temperature changes.

So, rather than allowing us to be less concerned about CO2 levels, this feedback loop should make us more concerned.

The economy will collapse if we stop using oil and gas

Several studies have shown that economies can grow while converting to renewable energy.   During recent years, some countries have taken steps based on their climate commitments to reduce greenhouse emissions, and their economies have not shuddered to a halt.   In 2017 CO2 emissions in the UK reached a level 38% below 1990 and not seen since 1890, largely as a result of reduced coal power generation.  In  a recent UK government ONS report Dr Amina Syed states that “The UK has shown evidence of absolute decoupling between 1985 and 2016, as gross domestic product (GDP) per head grew by 70.7%, while CO2 emissions fell by 34.2%.”  Obviously for countries with economies based on export of oil and gas or coal, such as Saudi, Canada or Australia, a move away from these forms of energy could be economically difficult, unless these industries are replaced by renewable equivalents.   However, for countries which have mixed economies, and are primarily consumers of oil and gas, switching to renewables can be neutral or beneficial to the economies.

Solar and wind are too intermittent to meet energy needs

This used to be a stronger argument against the viability of renewables, but advances in battery technology and other forms of storage such as pumped hydroelectric, as well as smart grid management are making this concern obsolete.

Existential Risk: from World Wars to AGI

Existential Risk: from World Wars to AGI

Reposting this article from 2015

Wandering Through my Mind

Recently I have read several books which have been unusually thought provoking.

The first of these is “The Making of the Atomic Bomb” by Richard Rhodes (he has a series of interesting books covering the history of nuclear weapons).  In the book, he describes the history of the physics and politics leading up to and during the Manhattan project, in which the US and its allies developed the first atomic weapons at Los Alamos and other sites.  One thing clear from his account is that once the program was underway, and had the backing of the US government and military, it was essentially unstoppable.  This was true even though the original rationale – the fear of a Nazi atom bomb happening first – was a moot point when eventually the atom bomb was tested at Trinity site in New Mexico, and subsequently dropped twice on Japan.  A…

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Existential Risk: from World Wars to AGI

Existential Risk: from World Wars to AGI

Recently I have read several books which have been unusually thought provoking.

The first of these is “The Making of the Atomic Bomb” by Richard Rhodes (he has a series of interesting books covering the history of nuclear weapons).  In the book, he describes the history of the physics and politics leading up to and during the Manhattan project, in which the US and its allies developed the first atomic weapons at Los Alamos and other sites.  One thing clear from his account is that once the program was underway, and had the backing of the US government and military, it was essentially unstoppable.  This was true even though the original rationale – the fear of a Nazi atom bomb happening first – was a moot point when eventually the atom bomb was tested at Trinity site in New Mexico, and subsequently dropped twice on Japan.  A second, somewhat disconcerting, point was that there were initially genuine concerns among some scientists that use of an atomic bomb could potentially cause an uncontrolled nuclear reaction which would ignite the earth’s atmosphere – and of course eliminate life on earth.  At least the scientists at Los Alamos checked their theory to be (almost) certain that this wasn’t the case.

The second book was “Thirteen Days”, Robert Kennedy’s insider account of the Cuban Missile Crisis when the world was brought to the brink of nuclear armageddon.  During the critical days of the title, John F. Kennedy was persistently under pressure from his military advisors to take preemptive action against the Soviet missile bases in Cuba.  Kennedy resists this advice, and steers through the crisis by continually thinking about the likely “next moves” which would follow any action from the US side.  In other words he tries to see things from Khrushchev’s perspective (who was also under pressure from the Soviet military) and make sure he always had a peaceful option.  What was behind Kennedy’s thought process?  One part of it was the influence of a book he had recently read regarding the outbreak of World War I, the next book on my list.

The Guns of August” by Barbara Tuchman describes the process of decision making among the European leaders, both military and civilian, as Europe headed into the outbreak of World War I.  In contrast to Kennedy’s careful avoidance of putting his opponent in an untenable position, the leaders in 1914 seemed to be continually narrowing their options to the point where war became inevitable.  Issues of national pride, personal grievances, over-reliance on military advice and so on all pushed things towards the catastrophic sad outcome.  There was also much naivety about the type of war which might result – with expectations built from previous experience before the age of trenches, machine guns and mass mobilization.  There is also a sense in which the arrival of WWI was precipitated by changes in the technology of warfare, which were not matched by changes in human decision making at the level of the relevant governments.  Railways – intended for beneficial use, but certainly employed as a form of weapon – shortened the timelines for mobilization of armies, and hence the time available for leaders to consider possible courses of action.   I think what Kennedy must have learned from his study of this book is that it is not weakness to avoid escalation, when the outcome is likely to leave everyone much worse off (namely dead in the 1960’s version).

330px-Superintelligence-Paths_Dangers_Strategies

The last book of my  selection is “Superintelligence” by Nick Bostrom, a Swedish philosopher at the University of Oxford and director of the Future of Humanity Institute.  Bostrom’s interests in general revolve around the big question.  What big question?  Actually, the survival of humanity.  Which, you have to admit, is a big question.  This particular book addresses his concerns over the introduction of human or superhuman level artificial intelligence, sometimes called artificial general intelligence (AGI), which seems increasingly possible even probable within perhaps the next few decades.   These concerns echo those recently brought to public attention by well known scientists and technologists such as Stephen Hawking, Sir Martin Rees and Elon Musk among others.   The scenario Bostrom envisages is that once AI becomes capable of slightly more than human intelligence, it will then have the capability to rapidly design more and more advanced versions of AGI, and there will follow an “intelligence explosion”.  Because this could happen very quickly, the first such super intelligence may end up being the only one – a so-called “singleton”, with enormous power of thought and more worryingly – action.  At the point, the interests of humanity hinge on a very critical question: what does the singleton “want”? Bostrom’s book spends a lot of pages looking at the challenges faced in making sure that we have AGI with the goals that we would like it to have, and how easy it is to get that wrong – the “control problem”.  One problem is that we tend to anthropomorphize something which is deemed to be intelligent, and assume that it will have a similar motivational framework to our own.  This is almost guaranteed not to be the case, since human motivation (good or bad) is the product of millennia of evolution.  Overall, Bostrom thinks that there is a reasonable chance that humanity can solve the control problem, which leads to a very positive outcome, with tremendous benefits to the human race stretching into the far future.

But, having said that, he does wrap up the book with this slightly unsettling paragraph:

“Before the prospect of an intelligence explosion, we humans are like small children playing with a bomb. Such is the mismatch between the power of our plaything and the immaturity of our conduct. Superintelligence is a challenge for which we are not ready now and will not be ready for a long time. We have little idea when the detonation will occur, though if we hold the device to our ear we can hear a faint ticking sound.”

Hmm.

So what are the connections (at least in my mind) between Bostrom’s forward looking book and the other three historical accounts?  It is firstly the phenomenon of an arms race, and secondly the immaturity of human conduct alluded to in Bostrom’s quote above.

The atomic bomb was the classic example of an arms race, where otherwise peace-loving scientists felt compelled to work hard and fast on the most destructive weapon imaginable at at the time – just because they could not be certain it wasn’t being done by someone else who would use it against them.  Knowing full well the dangers inherent in the technology, they judged these to be less if it was technology in their own hands rather than those of an adversary.  The mutual distrust theme of course underlies the whole history of the cold war which followed, with the every increasing arsenals necessary to prevent (in the minds of the superpowers of that time) a certain first strike by the other power, and hence the doctrine of mutually assured destruction (MAD) provided a safety of sorts.   In the run up to WWI a naval arms race between Britain and Germany took place, after the introduction by Britain of the “dreadnoughts”.  This naval competition led to mutual suspicion and hostility, and was a factor in Britain’s entry into the war.  There were also first strike arguments strikingly similar to those which  became prevalent  in the Cold War: “We don’t want war, but if it will happen anyway, then we must strike first, because time is of the essence with these new railways/ships etc.”.   The point to notice here is that an arms race typically is often motivated not by aggression, but by fear.

So it may be for the case of AGI according to Bostrom.  The tremendous competitive advantage that will accrue to the first nation, commercial company or even individual that achieves this goal will set up the almost inevitable dynamic of an arms race.  The worst outcome might be that some other party attains the breakthrough first, establishes a singleton and essentially has the world to ransom.  The risk is that in the effort to be first to achieve AGI, caution will be thrown to the wind, and insufficient care take regarding the control problem.  This is a truly frightening prospect.  It is perhaps similar to the dilemma the atomic scientists faced when deciding whether the atmosphere would set alight.  But the difference is more important than the similarity.  The atomic scientists were dealing with physics and their understanding of nuclear chain reactions, which may have been imperfect but within limits they understood.  It is far from clear that this will be the case for AGI.  This is why some very smart people like Elon Musk and Stephen Hawking are sounding the alarm.  But I wonder whether the right people are listening to it and believe it is not just a false alarm?