Monday 22 April 2024

Climate the Movie - debunked?

 Well not surprisingly the great boffins at Skeptical Science (sic) have published their debunking of Martin Durkin's recent film Climate the Movie, which took on the claims of the climate establishment by top scientists and appeared to emasculate them. Their main list (followed by more paragraphs of disapproval) was 25 points which I'll post here and then test each one as a judge would, with absolutely no bias either way.

Skeptical Science article



Quick rebuttal



Medieval Warm Period was warmer

Globally averaged temperature now is higher than global temperature in medieval times.



We're coming out of the Little Ice-age

Scientists have determined that the factors which caused the Little Ice Age cooling are not currently causing global warming.



It's freaking cold!

A local cold day has nothing to do with the long-term trend of increasing global temperatures.



Temp record is unreliable

The warming trend is the same in rural and urban areas, measured by thermometers and satellites.



It's Urban Heat Island effect

Urban and rural regions show the same warming trend.



Satellites show no warming in the troposphere

The most recent satellite data show that the earth as a whole is warming.



CO2 was higher in the past

Climate has changed along with CO2 levels through geological time.



CO2 is plant food

The effects of enhanced CO2 on terrestrial plants are variable and complex and dependent on numerous factors



CO2 is just a trace gas

Many substances are dangerous even in trace amounts; what really matters is the total amount of CO2 in the atmosphere.



CO2 lags temperature

CO2 didn't initiate warming from past ice ages but it did amplify the warming.



Increasing CO2 has little to no effect

The strong CO2 effect has been observed by many different measurements.



There's no correlation between CO2 and temperature

There is long-term correlation between CO2 and global temperature; other effects are short-term.



Ice age predicted in the 70s

The vast majority of climate papers in the 1970s predicted warming.



Models are unreliable

Models successfully reproduce temperatures since 1900 globally, by land, in the air and the ocean.



Climate's changed before

Climate reacts to whatever forces it to change at the time; humans are now the dominant forcing.



UAH atmospheric temperatures prove climate models are wrong

The most likely explanation for UAH data warming less than expected is that the UAH data set is biased low.



Clouds provide negative feedback

Evidence is building that net cloud feedback is likely positive and unlikely to be strongly negative.



It's cosmic rays

Cosmic rays show no trend over the last 30 years & have had little impact on recent global warming.



CERN CLOUD experiment proved cosmic rays are causing global warming

of one out of four requirements necessary to blame global warming on cosmic rays, and two of the other requirements have already failed.



It's the sun

In the last 35 years of global warming, sun and climate have been going in opposite directions



1934 - hottest year on record

1934 was one of the hottest years in the US, not globally.



Wildfires are not caused by global warming

Global warming worsens wildfires by creating drier conditions with more fuel for fires to spread further and faster.



Hurricanes aren't linked to global warming

There is increasing evidence that hurricanes are getting stronger due to global warming.



Polar bear numbers are increasing

Polar bears are in danger of extinction as well as many other species.



Great Barrier Reef is in good shape

Evidence clearly shows that both ocean warming and acidification due to human CO2 emissions are damaging the Great Barrier Reef

1) Medieval Warm Period was warmer Until 1999 it was. There was no doubt until then, the consensus was that it was warmer. Then came the hockey stick chart, one of a number offered to the UN IPCC, two similar and one different. This meant they had if nothing else been confused about the proxy records, using ice cores, tree rings, vegetation and other possibly contradictory methods to join together to form a reasonably credible representation of the last 1000 year's temperatures. The official line is it is still controversial and uncertain, which is definitely the case as otherwise more than two official diagrams could not stand for the same period. Some say it has been improved, others, using evidence such as vegetation unearthed around the Arctic Circle showing plants there which needed a far higher temperature to survive, while the southern hemisphere had so few records before the 20th century it had very little to begin with directly. So to be fair to both sides the jury is out on this one.

This is Michael Mann's hockey stick, currently used by the UN.

Here is a northern hemisphere graph, followed by the world graph used prior to the hockey stick and still used in some scientific circles.

This is vital to current climate policy, as if it can be proved, even on a balance of probabilities, that the MWP was warmer worldwide it confirms such warming is not only harmless but beneficial.

This is based on both the earlier temperatures (which so far have not been as widely disputed, as they were far more recent in the 18th century and correspond with many pictures and records of ice or frozen rivers much further from the poles than today) and the glacier sizes. These can be relatively easily measured from past records by geologists, and they did indeed start melting before the CO2 rose in the mid-19th century. However there appears to be no dispute whether the LIA actually existed as outside Skeptical Science it's part of official climate history. 

Global warming morphed into climate change, and the jetstream issue means when the jetstreams become unstable they draw more cold away from the poles. As some scientists blame this on man (the evidence is far from convincing) it means they are saying man made warming, sorry, climate change, can indeed cause colder weather as well as warm. This point was not used by the film to dismiss global warming, it was used by those who claim there is.

If you look up temperature records for virtually any period (raw, adjusted and anomalies) they do indeed differ. If any professional engineer, architect or doctor produced differing data you'd find another one, so climate scientists can't get a pass on this one. Easily demonstrated.

I can provide these till the cows come home, and virtually all the adjustments make the present warmer or the past cooler. That means they are not prima facie reliable using the dictionary definition.

Well it is real. Urban heat islands

They do generally, but not everywhere or always.
 See Troposhere graph Roy Spencer graphs for all UAH records.


CO2 was higher in the past

Yes it was.


CO2 is just a trace gas

It makes up around 0.04% of the air. If rising heat goes through the air it has a 99.96% chance of missing a CO2 molecule.

It always has before the recent graphs beginning around 1850, until you enlarge them enough and find they still do. 

The experiment always raised to prove this is wrong uses either a tube or a tank, both closed, to add CO2 and watch the temperature rise. As warmer air can't rise out of a closed vessel this experiment can't represent the air. Equations using spectral analysis make up most of the gap, and relies on sensitivity rates (temperature rise per CO2 molecule) set by the experimenters in advance rather than be found by the experiment. Also they can't model feedback, which increases increasing temperatures (positive) or reduces them (negative). The main two are aerosols (negative) and humidity (positive). The hypothesis is that warmer air is more humid which in turn does trap heat as water vapour is easy to measure. In fact the humidity has fallen in all three levels of the atmosphere, meaning the major element of feedback is absent.

The third element from rising water is clouds. As it's nigh on impossible to model cloud formation as it is not predictable enough, they will mean more water evaporating will actually form clouds which in their thicker forms block the sun. 


Ice age predicted in the 70s


This is a blanket statement and depends on the model and what they are trying to model. Rather than write an entire paper I'll simply quote the IPCC:

The value of long-term climate predictions was dismissed by the IPCC directly in 2001, saying exactly what its opposition had always said: "The climate system is a coupled non-linear chaotic system, and therefore the long-term prediction of future climate states is not possible"

14.2.2 Predictability in a Chaotic System The climate system is particularly challenging since it is known that components in the system are inherently chaotic; there are feedbacks that could potentially switch sign, and there are central processes that affect the system in a complicated, non-linear manner. These complex, chaotic, non-linear dynamics are an inherent aspect of the climate system. As the IPCC WGI Second Assessment Report (IPCC, 1996) (hereafter SAR) has previously noted, “future unexpected, large and rapid climate system changes (as have occurred in the past) are, by their nature, difficult to predict. This implies that future climate changes may also involve ‘surprises’. In particular, these arise from the non-linear, chaotic nature of the climate system

14.4 The elimination of models because they are in conflict with climate-relevant data is particularly important.

15) Climate's changed before Climate reacts to whatever forces it to change at the time; humans are now the dominant forcing.

I would read the summary of this article and draw your own conclusions.

16) Clouds provide negative feedback

It's called shade. Temperatures are always taken in the shade or the thermometer may melt on a hot day. What causes the shade which blocks so much heat from reaching the surface?


It's cosmic rays

The UN do not recognised solar changes as affecting the temperature in any significant way, but more research suggests it does, based on sunspots, solar output and other cycles which mean the magnetic output of the sun forms more aerosols in the atmosphere which allow more clouds to form, blocking out the sun.

There are more and more articles showing a very close correlation between solar activity and temperature so I suggest Skeptical Science goes back to school on this one.

18) CERN CLOUD experiment proved cosmic rays are causing global warming

"The CLOUD experiment studies how ions produced by high-energy particles called cosmic rays affect aerosol particles, clouds and the climate. It uses a special cloud chamber and a beam of particles from the Proton Synchrotron to provide an artificial source of cosmic rays. For this run, however, the cosmic rays are instead natural high-energy particles from cosmic objects such as exploding stars.

“Cosmic rays, whether natural or artificial, leave a trail of ions in the chamber,” explains CLOUD spokesperson Jasper Kirkby, “but the Proton Synchrotron provides cosmic rays that can be adjusted over the full range of ionisation rates occurring in the troposphere, which comprises the lowest ten kilometres of the atmosphere. That said, we can also make progress with the steady flux of natural cosmic rays that make it into our chamber, and this is what we’re doing now.”"

CERN experiment


It's the sun

 see points 17 and 18, this just merges the two.


1934 - hottest year on record

1934 was one of the hottest years in the US, not globally.

Well it was in America yes. 1934 heatwave

And Britain, apparently 1934 heatwave Britain

However, it is a red herring as whether it was or not it doesn't change any of the other points.

Well if they were they would be increasing as it warms.

This is correct. There is no trend in hurricanes.

24) Polar bear numbers are increasing

Populations of polar bears have tripled in 50 years and shown no connection with ice levels.

They are referring to coral, one of the oldest forms of life on earth, which has both thrived during ice ages and warm periods. An average temperature change of a few degrees does not affect coral in all but the shortest term where it may bleach for a while, which will then recover with new growth.

Acidification is an alleged symptom of rising CO2 but in fact the oceans remain alkaline. As it's not related to warming I'll leave that to the specialists.

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