Thursday 30 January 2020

Misdirection and Misinterpreting the Climate

You keep using that word - I do not think it means what you think it means

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This sequence on climate denialism started with On Climate Denialism – Deny Deny Deny.  Hard-core denialists just say “No, there is no climate change/global warming” or words to that effect, but it’s a difficult position to maintain unless they buy into the conspiracy theorising necessary to explain away all the evidence.  Not everyone is equipped with the special blend of imagination and credulousness that is necessary to believe conspiracy theories, but fortunately for climate denialism, there is a softer option – misunderstanding.

There are two aspects of misunderstanding in this context, misunderstanding the issue and misunderstanding the evidence.  If you are a climate denialist, you can spread misunderstanding by misdirecting attention to side issues or specious arguments or you can misinterpret (or misrepresent) real data in a selective or more explicitly deceptive way.

Note that it is possible misdirect and misinterpret unintentionally.  I would use this (in part) to delineate between a climate denier and a climate denialist – if its unintentional, the actor is probably just a denier (or naysayer), but when there’s an intent to distract or mislead, then you’ve got a denialist on your hands.  Further note that misinterpretation is not limited to deniers and denialists, activists and alarmists can also be guilty of it.  To avoid a difficult, nuanced discussion, they may also sometimes be guilty of misdirection, highlighting the evidence that clearly supports their case while drawing attention away from data that indicates that the argument is more complex than they would like (for example it is rare that climate activists will agitate for new nuclear power plants on the grounds that they are far safer today than they used to be and they produce far less CO2).

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Misdirection is possibly one of the easiest tactics for a climate denialist, made easier by climate activists who overreach or are guilty of their own misdirection.

Two examples that come to mind recently are Greta Thunberg and the 2019/2020 Australian bushfires.

Greta Thunberg is a student activist for action with respect to climate change.  She’s not a climatologist, or even a scientist working in a related area.  She has no formal qualifications at all, unless you count all the awards that she’s been granted.  She has a diagnosed mental condition, being on the autism spectrum with Asperger syndrome, obsessive-compulsive disorder and ADHD.  When she first came to prominence, she was only 15.

While Thunberg has been successful in drawing the attention of global media onto the issue of climate change, she brings little more than enthusiasm and a willingness to stand up and make demands for action.  Neither her comments nor the response to her by media organisations and other activists prove or disprove scientific evidence-based claims associated with climate change.  Even if Thunberg grossly misstates or exaggerates the extent of global warming or the consequences of it, the facts of the matter will remain the same.

Nevertheless, climate denialists such as the Murdoch press (News Corp [which owns a number of right-wing leaning newspapers, including the Daily Telegraph referred to in the link], Fox News and Sky News), other right-wing media (Breitbart, Rebel Media, etc), some libertarian media (Spiked), right-wing think tanks (Heartland Institute, etc etc) and a raft of bloggers (Joanne Nova, Tony Heller, etc etc) love to hate Greta and crow about her every stumble and misstep.  She’s just a schoolgirl, she’s mentally ill, she’s the focal point of some sort of environmentalist cult, she’s not writing all of her social media posts, she’s being used and controlled by climate extremists (or dark anti-western forces) and so on.

Some of those things are true.  Perhaps all but the parenthetical conspiracy theory one and the one about the cult (although maybe there is what could be called a cult of adoration that is coalescing around her, perhaps she might be deified or canonised in the future, stranger things have happened – when I search for “patron saint of climate change” I get this but the official [catholic] patron saint for that sort of things is actually Francis of Assisi [strictly speaking though, he’s the patron saint of animals and ecology]).

As said though, the faults of Greta Thunberg (and those around her) don’t impact on the fact, or otherwise, of climate change.  What they can do however, with great effectiveness, is distract.  So long as the attention of the public is encouraged to be on the phenomenon of Greta Thunberg as media whore, or misguided crazy person, or abused little schoolgirl, the public isn’t going to be giving any thought to the wealth of evidence that is available to support the notion that climate change is happening.

The 2019/2020 Australian bushfires are slightly different.  They were really dominating the news in December 2019, until viewer fatigue set in and attention was distracted by various other newsworthy events (impeachment of Donald Trump, the emergence of a novel coronavirus, some royal kerfuffle in the UK, Brexit finally looking certain).

The most distracting claim is that climate change didn’t cause the fires.

This is almost certainly true.  Australia has bushfires every year.  Australia has large bushfires every year.  As you fly northwest from Melbourne at night, over Northern Territory, it’s not uncommon to be able to look down and see massive bushfires burning without any human intervention at all – neither as a cause nor as the agents of the fires’ end.  Bushfires in Australia are a fact of life.

It’s also true that some of the bushfires were lit by idiotic humans.  It gets a bit complex because once a bushfire is ignited, since it takes off and starts creating conditions which are suitable for creating new fires – embers are caught in updrafts of hot air and can cause new fires a kilometre or more away, pyrocumulonimbus thunderstorms can form and produce dry lightning that can start new fires kilometres away and finally, an area that has had a fire go through can remain hot for days with roots smouldering for weeks


So it’s possible that one person accidentally (wheel fell off a trailer and showered sparks into dry grass), carelessly (smoker threw a cigarette butt out of the window, or a camper failed to properly extinguish a campfire, or a helicopter landed on dry grass with a hot landing light) or deliberately ignited a bushfire, say in East Gippsland and, not long afterwards, the entire area was ablaze eventually with millions of hectares burnt.


What was interesting to note here is that there is a strong correlation between a media outlet or blogger’s position on climate change and the likelihood that they would misreport the number of people who had been arrested for arson during the period of these horrendous fires.  There was, for example, a myth going around that about 200 people had been arrested “for arson” during the 2019/2020 bushfire season (since 8 Nov 2019). 

In early January 2020, PragerU put out a popular video (apparently more than two million hits) in which the following claim was made – noting that Americans call bushfires “brush fires”, see further below for a brush fire in Australia:

The popular narrative is that Australia’s fires are caused by climate change. But the facts say otherwise… Since November 8, 2019, nearly 200 arsonists have been arrested for starting brush fires in Australia. The arsonists were responsible for about 50% of the bushfires. Not climate change. Arsonists. Repeat that: Not climate change. Arsonists. But the left doesn’t care, because this fact doesn’t agree with their ‘science.'

(A not so scary brush fire)

The Australian (News Corp, linked to the Australian version of Sky News, both of which have a distinct anti-climate change stance), still had as of 28 Jan 2020, a headline that reads “Bushfires: Firebugs fuelling crisis as national arson toll hits 183” (in an article with the dateline 15 January 2020).

The body of the article makes clear that this figure is since the beginning of 2019, rather than since the beginning of the 2019/2020 fire season.  The Australian article mentions the NSW police report that was the basis of the myth being spread by PragerU, stating that legal action had been taken against 184 people for bushfire-related offences, of which only 24 were arson. 

Now arson is a really bad thing, and quite emotive in a country which has lost almost three thousand homes to fire (at time of writing), but the fact that it is true that there were some arsonists does not mean that all bushfires were lit by them.  There are a raft of reasons why bushfires start and it is thought that only about half of them are started deliberately by humans (or suspected to be) – many are also started accidentally or carelessly.

However, once a bushfire gets started, either accidentally, or deliberately, its behaviour – which contributes to how devastating it becomes – is dependent less on the source of ignition and more on the conditions in the area that is burning.  It is here that another media and climate denial fuelled argument arises: is the severity of the Australian bushfires in 2019/2020 due to climate change or something else?

First, I should acknowledge that there have been plenty of talking heads who have stated with great gravitas that the fires are due to climate change.  For example, even Piers Morgan suggested that the bushfires are caused by climate change and he is not quite the traditional friend of the environmentalist or climate change activists (note his focus on climate change activists being hypocrites for using air conditioning, his body language during the discussion with Laura Tobin, his highlighting of Thunberg’s youth, her being “hysterical” and having Asperger syndrome, the “unthinkable compromise” and the final claim that perhaps Thunberg was “hamming it up a bit”).

There are also scientists (and here and here) and activists who have claimed that the bushfires have been exacerbated, or “super-charged” by “a changing climate”.


It might be true that the climate exacerbated the fires, but there are other theories.

Humans have been using fire to control fire in Australia for tens of thousands of years, what has become known as “cultural burning” by the Australian Aboriginal peoples (also referred to as traditional owners, or traditional custodians, or original inhabitants, or indigenous – each term has its own problems).  When Westerners came to Australia and took control of the land, they tended to prevent cultural burning, although they did use fire for land-clearing and preparation for new growing seasons (cane fields for example are burned at the end of the season).  As a consequence, the amount of fuel available to burn in forests increased and increased until there were some truly catastrophic fires.  (California has suffered similarly, with their very successful fire prevention policies.)

In the 1920s, foresters in Western Australia started using fire to reduce fuel load (the amount of leaf litter, fallen branches etc) in cooler and damper weather in preparation for the bushfire season.  It’s a little complex though because not all land is available to burn, due to various ownership of the land, there’s a limited amount of time in which to burn and there are questions about the most effective burn rotations since too frequent and you kill everything, too infrequent and there’s too much fuel load and mature trees survive fire better, but if you don’t let any trees get to maturity due to your burn rotations you’ve got a different problem. 

The simplistic argument is that if we remove most of what tends to burn then, when there is a bushfire, there will be less fuel and a bushfire won’t be as severe.  It does sound pretty obvious.  According to Donald Trump, for example, efforts in Finland to keep their forests well-raked have been instrumental in limited bushfires in that country.   This would actually work, to a certain extent, but Australia is rather large.  The authorities aren’t going to be able to get millions of hectares raked, so they are left with the option to burn it away – and each year tens of thousands of hectares are burned on a rotation basis, the idea being that there are large areas in the forest with low fuel load and any bushfires that start will be more easily controlled.

A problem is that this theory is based on the notion that a fire will quickly move through an area that has had a fuel reduction burn, consuming the limited fuel left on the ground, leaving the mature trees largely untouched.  When the conditions are bad, however, with extreme temperatures after months, if not years of drought, the trees themselves burn.


Once the crowns (the tops of the trees) are burning, it no longer matters too much what is lying on the ground.

The real argument therefore resolves to a question about the conditions in which the Australian bushfires happened … were the extreme heat and/or the drought that preceded it due to climate change?  Possibly.  Denialists argue that there’s no conclusive evidence that climate change even exacerbated the bushfires, because Australia has had droughts before, terrible droughts and this is far from the first heatwave experienced together with bushfires.

This is distraction, rather than outright denial, because there’s some truth to those claims.  What a denialist will try to avoid accepting is another truth: there’s no conclusive evidence that climate change had no impact whatsoever on the severity of the bushfires.  I suspect the truth lies somewhere in the middle, there was some impact due to climate change, making the fires worse than they otherwise would have been, the drought may have been exacerbated, rather than caused by climate change, the weather (not climate) systems contributed to hot air being channelled from the middle of the continent to the south eastern part of the country but warming climate ensured that there was a lot of heat to warm that air and records do show that we had some unprecedented temperatures in that period (warmest day for the whole of the country on average for example).

There are some interesting graphics that imply that the changing climate may have had an impact:

(modified from here)

(taken from here)

(modified from here using this)

What we can see, from the fruits of my labours above, is that the distraction works.  I spent time, during the drafting of this article, looking into whether climate change had any impact on the bushfires.


But the point is that, even if denialists could show definitively that the bushfires were not due to climate change and were due instead to no more than a normal combination of weather and human idiocy (both in lighting fires and not acting sufficiently to prevent fires), this would not change the fact that there are records showing that the temperature is rising across the globe, that sea levels are rising and so on.

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Misinterpreting the term “climate” and data about the climate is another excellent way to promote misunderstanding.

The most common example of this is to conflate the terms “weather” and “climate”, thinking of them as being the same thing, and then arguing either that there has been hot weather somewhere in the past (therefore hot weather today is no surprise) or that there is currently cold weather somewhere (and therefore where’s the global warming?)  Denialists (and deniers) will bring up the fact that in the 1930s there were heatwaves that led to record temperatures, some of which stand today.  They will point to cold spells, particularly in the US with their polar vortices, but also in Europe (the Beast from the East) and say something along the lines of “it’s really cold today, global warming must be a hoax”.  Since some of them are not averse to blatant cherry picking, they might even point out that it’s been cooler than usual recently in New Delhi and Anchorage (I’ll leave it to the reader to work out which is which):



Note that I had to search for quite some time to find these two examples of distinctly cooler than average temperatures in the past two months.  The vast majority of cities had December temperatures that range from significantly warmer than average (such as Perth, Canberra, Sydney,  Sevastapol, Tokyo, Santiago, Tangiers, Stockholm and Moscow) through a bit above average (Mawson Station, Darwin, Melbourne, Auckland, Calgary, Washington DC, Rio de Janeiro, Mombasa, Kabul and Mombai) and about average (Hobart, Bangkok, Beijing, Ulaanbaatar and Los Angeles) to slightly below average (Johannesburg, Reykjavik and Montreal).  I tried to find representative cities in each continent, but Australia has been much in the news with the bushfires, so I took a few cities from there.

The evidence for climate change is not that the temperature, every single day, in every single location, is rising consistently.  It’s that the average temperature, across the globe, averaged over the span of a few years can be seen to be rising (ed. strictly speaking, it's actually over a couple of decades).  There will be variations over time and there will be geographical variations.  For example, 2018 was significantly cooler globally than were both 2016 and 2015 (but not 2014).  Your region might have been significantly cooler in 2016 than in prior and following years, despite the fact that globally 2016 was the hottest year on record (marginally warmer than 2019, which was the second hottest year on record, narrowly eclipsing 2015).  That doesn’t change the fact that, overall, 2015 and 2016 (and 2019) were warm years.

Heatwaves tend to be due to weather rather than climate.  It’s worth noting that a heatwave is defined as “a prolonged period of abnormally hot weather”, so if the climate just warmed up by a small amount each year but temperatures were otherwise unremarkable, there’d never be a heatwave.  A heatwave is due, for the most part, to warm air moving from where it is normally warm to a place that normally has mild temperatures, leading to abnormal heat.  Australia provides a good example of this phenomenon.

In February 1933, there was a heatwave in Perth, Western Australia.  The synoptic chart for that time looked like this:


It’s from a long time back, well before satellites and computers, so it should be taken with a pinch of salt, but what you can see is a high pressure system sitting in the Bight (to the south of the continent).  Air would be moving around that system in a clockwise direction, meaning that winds would push warm air from the centre of the continent down towards Perth in the bottom left hand corner (ie the south-west).

A more recent heatwave looked like this:


Again, warm air would be pushed from the centre down to the south-west, which happened, leading to temperatures in the high 30s despite it only being October.

Neither event could seriously be considered to be climate change related, but that doesn’t stop climate denialists setting up strawman arguments to distract attention away from solid evidence of climate change.

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When you hear a climate denialist railing against some climate activist, or climate related scientific measurements or modelling, or mainstream media, it might be worth taking a moment to consider: what would be the consequences if this person (Greta Thunberg, Michael Mann or some unwashed radical vegan), measurement, model or media outlet were wrong?  Would that negate the wealth of evidence that indicates that climate change is real and is happening?  If not, then there’s little point getting riled up by the rhetoric.

And if they bring up a heatwave that happened in the past, check to see if it was in a period that we already know was hotter than average.  Also ask what the following winter was like (for example, 1934 was a warm year in the US, but the winter was very cold, so the average temperature was still lower than in the 1940s).  When you have warmer summers and warmer winters, as we are beginning to have all too frequently, it’s a signal that things are not all well.  But even then, remember that evidence of a heatwave in the past is not evidence that there is no heating trend in the climate today.

If you’re in a discussion with a denier, ask for evidence against climate change.  If the best they can come up with is the notion that some person said something that wasn’t true or there was a notable hot spell at some time in the past, then they clearly don’t have a good argument.

As for misinterpreting the data, I intend to touch on an example of that in an article about climate modelling and there may well be other examples in an article or two on my discussion with my climate denier friend, JP.  One that has already been touched on relates to sea level rise, where a chart was presented that looks very much like there’s very little rise:


The choice to display minimum, maximum and mean justifies the use of the scale in terms of metres and it can be easily observed that the sea level has risen only a fraction of a metre over a period of more than 100 years.  However, the same data can be presented a different way and from that it can be easily seen that sea level rise is in accordance with global measurements (currently about 3.6mm/decade).

This chart was presented to me as evidence that the sea level rise isn’t accelerating, but reanalysis of the raw data indicated that it is in fact accelerating, just like CSIRO and University of Hawaii measurements are telling us.

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And why did I have the quotation from “The Princess Bride”?  It’s both because the word was “inconceivable”, which is the thrust of some denialists, they simply can’t conceive of the climate being affected by humans, and because the person who was being accused of misusing (and thus apparently misinterpreting) the word, Vizzini, was a swindler who at one point plays a variation of the cup and ball game, a classic game of distraction.  Of course, the game didn’t end up going too well for him, but the same could be the case for climate denialists in the longer term if they are successful in catastrophically delaying action to prevent or mitigate against further climate change.

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Next: “A Climate of Minimisation”

Wednesday 29 January 2020

Sea Level Denialism

For the purposes of providing evidence of a prominent climate denialist who denies that sea levels are rising, as mentioned in On Climate Denialism, I present Nils-Axel Mörner, retired paleogeophysics and geodynamics head from Stockholm University.  Along with believing that a period of cooling is imminent he also believes that sea-levels are going to decline rather than rise (which would make sense if we enter a period of cooling and ice coverage on land masses such as Antarctica and Greenland were to start building up again).  He further argues however that there is no (rapid) rise in the sea-level going on today.  It’s unclear what “rapid” means in this context – Mörner seems to vary his claim from no more than 1mm a year over a long period (since 1850 for example) to nothing (since 1970 or since 1992).

An argument along the same line was presented to me personally by my friend, JP, related to the readings at Fort Denison in Port Jackson (where Sydney Harbour is located).  The gist was more about the lack evidence of an accelerated rise since 1960 (in accordance with the “Hockey Stick” and which was raised in response to an article quoting the CSIRO).

JP sent me this home-made chart:


Fair enough.  It doesn’t really seem to be showing much of an increase, in terms of metres, perhaps 100mm over a period of 100 or so years.  There was also a complaint that the article referred to only mentions dates since 1993 which is coincidentally a low point, rather than since 1914 when measurements began.  I dug up another chart in reply:



The 1993 date relates to the beginning of dedicated sea level telemetry from satellites.  Note the chart is expressed in inches, not metres (a metre being slightly less than 40 inches).  It’s also showing the global average rather than readings at a single tide gauge.  According to NASA there doesn’t really appear to be much acceleration in sea-level rise since 1993, but the rise is nevertheless relentless (and there’s more significant acceleration over the longer period since 1880):


I am aware that looking at one data point (or one data collection station) out of context is fraught with danger and won’t necessarily tell us much about the global situation but indulge me for a moment.  I downloaded data from Fort Denison, and plotted 1993 to 2018 using a scatter diagram (note that others based on the same data set are mentioned in Sea Levels Rising):



That shows an increase of, in average, 3.6 mm per year or slightly higher than the global average – so the local data collection station output was representative of the global data after all.  The remaining question then is what did the IPCC AR5 (2013) projections look like (note projections, not predictions):


That black line at the end is 3.6mm/year, so it seems that while it’s a little lower than for RCP2.6’s central estimate, it still lies within the range of projections.  RCP2.6, by the way, is the mildest scenario in which radiative forcing peaks at 3 W/m2 before 2100 and then declines.  Radiative forcing is a measure of the imbalance between energy into the climate and energy out.  Peaking at 3 W/m2 is equivalent to peaking at 475 ppm CO2.  Currently we are at about 410 ppm CO2 with an annual increase of a bit over 2 ppm/year which means that, if we don’t start turning things around, we will exceed RCP2.6 just after 2050.  The next most lenient RCPs are RCP4.5 and RCP6.0, which have us hitting 4.5 or 6.0 W/m2 before levelling out after 2150 – or 630 ppm and 800 ppm CO2.  At 2 ppm/year, with no change to our climate policies and practices, we will hit 620 ppm by 2130 and 800 ppm by 2215.


The trouble is that the rate at which the CO2 concentration is increasing is also increasing, so those dates are very conservative:

 

The positive news here is that the sea levels aren’t increasing as quickly as some projections were telling us they might but, on the other hand, they are increasing.

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I was going to address JP’s claims with respect to sea levels together with sea level-relate climate denial, but the article got too long, so I broke this part out, leaving the other section in Sea Levels Rising.

Sunday 26 January 2020

On Climate Denialism - Deny Deny Deny!


I don’t hope to cover the nature of climate denialism in its entirety in one single argument, but rather intend to provide rough categories of the types of denialism and motivations of denialists.

I’ll start with the categories of denialism because they seem to be easier and, to a certain extent, more clear-cut.

The most hard-core type of denialist simply denies that climate change is happening.  Examples of this are those who make claims that:

global warming may well have been happening a bit, but it has now plateaued,
historical records have been tampered with to give only the appearance of global warming, and
hot temperatures were experienced in the past (so why are we making a fuss now?)

That first is one that gets renewed every few years, whenever the records can be twisted into supporting the claim, usually based on a longer period where the first year is abnormally warm and the final year is unusually cool such as 1983-1996, 1998-2012, 1990-2000, 2003-2013 and 2016-2019 (but 2016-2018 was particularly exciting for this crowd, with a short term drop of more than 0.5C per year).  But when you look at the entire period in context, it becomes significantly less compelling (“Extra! Extra! Read all about it!  2018 is the Coldest Year since 2014 (which was the warmest year on record up until that point)!”):


It’s true that a glacier is growing, but again, this is a fact taken out of context.  One glacier is growing in Greenland but the entirety of the ice sheet is still diminishing.

I addressed sea ice in the Ice Extent Challenge and sea levels in both Sea Levels Rising and Sea Level Denialism.

There are quite a few climate deniers in the “it’s all due to the sun and it’ll start cooling soon” camp.  One of these is David Evans, husband to Joanne Nova, who is a proponent of the notch-delay solar theory and has made a bet with Brian Schmidt that global warming will not be as significant as was being projected (it’s quite a complicated bet, so it’s better that you read the details at the source).  The first phase of that bet came due this year, for Brian to win $1500, the climate needed to have warmed by 0.17C over the decade.  It warmed by 0.29C over the period by my calculations.  I’ve not yet seen any response from Evans or Nova, but Schmidt is willing to donate his winnings to support recovery from the bushfires being experienced in Australia.

The crowd who are convinced that we are just about to enter into a cooling period, if not a full-blown ice age, are quite resilient.  Each time there is two or three years cooling from a high point, they come out of the woodwork to proclaim a different type of doom.  What also brings them out is any major snow or polar vortex event, as if a local weather event were evidence of global cooling.  Their simplistic argument is “if the world is cooling, why is it snowing/cold where I am?”  Senator James Inhofe ran the same sort of argument when he carried a snowball into the US Senate in Washington DC in 2015 (and that was before the US had a president who had even earlier claimed [in 2012] that climate change was a hoax perpetrated by China [he has since backed up a tiny bit on the climate denial, verbally, although his actions don’t quite mesh with his words]).

Then there is the claim that there is some tampering of climate records.  This is a common refrain of Tony Heller, who is a master at cherry picking.  It is true that there are corrections made to historical temperature records.  Occasionally arcane explanations are provided as to why these corrections are made – usually due to interpolation of trends across multiple sites to eradicate erroneous readings, or to account for relocation of weather stations (which tends to happen after years of encroaching suburbia, which has an incremental impact on readings).  However, even if we were to accept all of Heller’s carefully cultivated evidence, it’s not a major issue that the historical records now tell us that the temperature has risen by 2.0C since 1884 rather than just 1.5C.  Even 1.5C in that time period is not good and the trend continues to be warming.

Sometimes, when digging through the historical records, the aim of the denialist is to find not so much evidence of record tampering, but rather evidence of either past warm periods or scientists being worried about global cooling.  There are paleoclimatologists who point out that thousands or hundreds of thousands of years ago, it was as warm as or warmer than it is today (or that CO2 was higher than today), which is true enough.  There are news reports of heatwaves way back into the early 1900s and beyond.  That in itself is not a surprise, given that a heatwave is a period abnormally warm weather (the term “heatwave” wasn’t used that much before the 1920s, but periods of abnormally warm temperature would have happened anyway).  The problem is that this definition allows for a moving feast, given that the “normal” shifts.  That said, there are high temperature records that still stand from the 1930s (Washington DC, for example).  The problem is that there’s a lot of cherry picking involved.  Warm summer temperatures are trumpeted but the very cold winters are ignored.  Additionally, a single location being very warm on a few days one year is no guarantee that the entire globe is going to be warm that year, as can be seen in the graph at the top of this article.  1930 was a bit warmer than 1929, but it was a lot cooler overall than the early years of the 1940s (which were a bit of an anomaly in themselves).

It’s similar with worries about global cooling.  It is true that a group of scientists in the 1970s were concerned that the world was going into a cooling period, which was not totally unreasonable, given that there was a cooling trend apparent in the records since the 1940s.  However, what is ignored is that there were more scientists at the time who were effectively saying that the apparent cooling trend was masking the real trend which was for warming (Peterson 2008):


So far, I have not seen anyone who seriously claims that there has been no warming whatsoever over the 20th century and since.  Perhaps there are some out there, but I’ve not had the pleasure of deconstructing their illusions.

The bottom line is that, to be a real hard-core denialist, you need to be able to strictly filter your data.  Not many people are able to do that, but there are other options.  You could misrepresent (or misunderstand) the data.  You could minimalise the consequences of the data.  Or (and if I write an entire article on this one, it’s surely going to be quite short), you can just ignore the data, and any potential consequences.  More on these later.

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Next: “Misdirection and Misinterpreting the Climate” or “You keep using that word - I do not think it means what you think it means”