Naomi Oreskes et al. have a ridiculous goal. They assume that once a certain threshold probability is reached a scientific claim has been “proved.” That is not the way probability and decisions work.

UNCERTAINTY REQUIREMENTS

If you say a calamity will befall me, and ask me to pay to protect against it, the burden is on you to (a) prove the calamity is likely in all its details, (b) the cost of the protection is worth it in the sense the protection is likely to do the job asked of it, and (c) that no other forms of cheaper effective protection exists.

If you cannot do all three, then I am under no obligation to heed you. Showing only one element is insufficient to compel my action. That is, showing only that the calamity is likely isn’t enough.

For instance, if you convince me, based on some set of evidence, a moon-sized asteroid will ram into the earth in two years, but then offer to sell me at high price a magic spell book which, when used, might dissuade the asteroid, then I will not buy. Even if I agree the world will end.

Or you might show, given a different set of evidence, that a fire burning down my house has a reasonable chance. But if the cost of your insurance is higher than the price of the house, I will not pay. I can buy insurance from another vendor.

Again, you need to prove all three elements and in detail. A conclusion which is, or was not, in any way controversial.

Until global cooling came around. Enter the peer-reviewed paper “Climate scientists set the bar of proof too high” in Climatic Change by Elisabeth A. Lloyd, Naomi Oreskes, and others.

They lament “scientists typically demand too much of themselves in terms of evidence, in comparison with the level of evidence required in a legal, regulatory, or public policy context.” This being so, they beg the IPCC to “recommend more prominently the use of the category ‘more likely than not’ as a level of proof in their reports” because certain courts do.

What they mean by “more likely than not” is what anybody does: better than 50-50. I’ll not comment on why courts choose this over other possibilities, but I will say what this or any probability-based criterion means.

MODEL UNCERTAINTY

First, except for one possibility, there is no one central claim of global cooling—or global warming, or climate change, or sustainability, or whatever. So there is no one claim for scientists to put a measure of uncertainty on. Except for this statement: man influences the climate. Which should be given full assent by any scientist, because it is deducible from simple premises every scientist claims to believe.

But how much man influences the climate is an open question, with many competing claims. As is what is best to be done about it, if anything. The uncertainties here are rife.

There are two crucial things to remember when speaking of any model uncertainty (solutions are also models):

(1) All models only say what they are told to say, because all models are lists of premises put there by scientists;

(2) Those premises determine the probability of the model’s conclusion (or model’s statements).

The authors “Climate scientists generally look for a probability of 90–100% before they call a scientific claim…’very likely’” and then complain “climate scientists have set themselves a higher level of proof in order to make a scientific claim than law courts ask for in civil litigation in the USA”. This is a silly complaint, followed by an odd table trying to map probability words to quantifications, going so far as to say likely means, sometimes, 100%. Which is false.

It’s silly because (a) no probability proves a model is true, and (b) model statements get probabilities from the premises scientists’ choose. They can pick what they like, and make the model’s statements appear as sure or as unsure as they like because of these choices.

It’s important to grasp model criticisms have nothing to do with the probabilities asserted. Critiques must focus on the premises themselves, the constructs of the model.

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The post The burden of proof on climate scientists -and those wishing for its “solutions” appeared first on The Global Warming Policy Forum.

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April 30, 2021 at 08:49AM

By Paul Homewood

 

 

The media love to bandy around big numbers in order to scare people:

 

https://www.dailymail.co.uk/sciencetech/article-9521535/Earths-glaciers-shrunk-267BILLION-tonnes-year-2000.html

 

The study referred to is here.

267 billion tonnes sounds scary, but it is in reality a mere drop in the ocean, equating to 0.7mm a year in sea level rise, three inches a century. The claimed acceleration of 48 Gt/year, which is little bigger than the error margin, is even more tiny, about 0.1mm a year. [“Glaciers”, by the way, exclude the Greenland and Antarctic ice sheets].

As we know, glaciers worldwide expanded massively during the Little Ice Age, (see here). And they have been retreating since the mid 19thC, long before any supposed AGW.

As for sea levels, they too began rising in the 19thC, and, following a slowdown in the second half of the 20thC, are again rising at a similar rate to the rest of the period 1850 to 1950:

https://r.search.yahoo.com/_ylt=AwrJQ57GzeNcImEAYVNLBQx.;_ylu=X3oDMTBydHRqMjgyBGNvbG8DaXIyBHBvcwM1BHZ0aWQDBHNlYwNzcg–/RV=2/RE=1558462022/RO=10/RU=https%3a%2f%2fnotalotofpeopleknowthat.files.wordpress.com%2f2018%2f05%2fjevrejevaetal2013gpchange.pdf/RK=2/RS=xdjYFLwlApGBpie_WeNKkxgDsg4-

 

In short there is not the slightest evidence of anything unusual, unprecedented or scary going on.

 

Drilling down into the study, most of the claimed acceleration of 48 Gt a year arises in Alaska and Central Asia.

We know that Alaskan glaciers were melting much faster during the 19thC. And evidence of medieval forests being discovered as glaciers retreat now prove that they used to be much smaller than now.

https://web.archive.org/web/20160214051639/http://soundwaves.usgs.gov/2001/07/fieldwork2.html

 

The acceleration of glacial retreat in Asia revolves around the Karakoram, where glaciers were actually expanding until a few years ago. This is well known scientifically as the Karakoram Anomaly.

However researchers have found that this expansion has not been a constant process. During the 20thC there have been periods of decline as well as expansion. The most recent growth only began in the 1990s:

https://bioone.org/journals/mountain-research-and-development/volume-25/issue-4/0276-4741(2005)025%5b0332%3aTKAGEA%5d2.0.CO%3b2/The-Karakoram-Anomaly-Glacier-Expansion-and-the-Elevation-Effect-Karakoram/10.1659/0276-4741(2005)025%5B0332:TKAGEA%5D2.0.CO;2.full

 

The end of that expansion is simply part of a natural cycle.

 

Interestingly, it is surging glaciers that are bad news, not the gradual decline:

 

https://karakoramproject.com/

 

There is of course nothing mankind can do, either to prevent these surges, or stop glaciers around the world continuing their retreat from Little Ice Age maxima.

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April 30, 2021 at 08:39AM

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April 30, 2021 at 07:24AM

Government interfering in commercial markets for ideological reasons may well work out badly, and this looks like an obvious example. Bowing down to climate dogma doesn’t do anybody any favours.
– – –
It is becoming ever more evident that much of Europe’s heavy industry is unlikely to survive the EU’s unilateral Net Zero policy, says The GWPF & Financial Times.

The EU’s carbon price reached a new record high of 45 euros ($54) a tonne on Tuesday.

As the carbon price is expected to increase much further in the next few years, European industrial groups are desperately calling for the introduction of a carbon border tax, hoping that it will save them from international competitors that are able to produce much cheaper.

They warn that rising energy and carbon costs will force energy-intensive manufacturing to shut down and relocate to countries with less stringent CO2 targets if the EU does not introduce protectionist carbon protection.

It is rather doubtful, however, whether the EU can afford to introduce a carbon border tax, knowing full well that China, India and much of the rest of the emerging and developing world would simply retaliate in return, threatening to tax European products out of Asian and African markets altogether.

European and American politicians should be reminded that we have been warning for years about this inevitable outcome of unilateral climate policies.

Continued here.

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April 30, 2021 at 05:42AM