Bishop Hill Lilley in HuffPo
Jun 22, 2013 Climate: Sceptics Kudos to the Huffington Post for giving Peter Lilley space to put forward a dissenting view on climate change (see here). His thoughts will be unremarkable for BH regulars, but might come as a surprise to many HuffPo readers.
What most clearly distinguishes the Catastrophic Global Warming cult from science is that it is not refutable by facts. As Parliament enacted the Climate Change Bill, on the presumption that the world was getting warmer, it snowed in London in October - the first time in 74 years. Supporters explained "extreme cold is a symptom of global warming"!
The Met Office - whose climate model is the cult's crystal ball to forecast centuries ahead - has made a series of spectacularly unreliable short term forecasts: "Our children will not experience snow" (that was 2000, before the recent run of cold winters), a barbecue summer (before the dismal 2011 summer), the drought will continue (last spring before the wettest summer on record). Now they say that rain and floods are the new normal. But - hot or cold, wet or dry - global warming is always to blame.
I'm amused by some of the comments, with the outraged HuffPuffers apparently unsure how to deal with him. Lilley's observation that he accepts the existence of the greenhouse effect has been met with angry denunciations and claims that he is arguing with 97% of scientists. His noting that he studied Physics at Cambridge is met with accusations that he is unqualified to comment.
What fun!
[Please note that comments about radiative physics will be snipped]
Reader Comments (163)
"Except when it is grounded-ice at the Antarctic periphery, when melting will reduce sea volume."
michael hart
That may not be the case.
A floating iceberg displaces a volume equivalent to its own mass in water. Melting will turn it all to liquid which displaces the same amount. There is no change in water level. Try it with an ice cube floating in a glass.
A grounded ice shelf has a higher proportion of ice above water level than a floating iceberg. This means that the shelf displaces less than its mass of water. When it melts, the excess above-water ice will produce an increase in water level. Try filling the glass with ice cubes and then adding water to 3/4 of the full depth. Watch the water level rise as the ice melts.
Jun 24, 2013 at 6:57 PM | Entropic Man
An interesting idea EM. As Rhoda said - why did you not propose it before? I actually think it could be worked up into something of value.
Unfortunately, I no longer have access to labs that could perform this experiment. Perhaps a university out there? If it could be worked up into somethig that several agree could produce new data then it should not be too difficult for a MEng project. I would also wish to see varying relative humidity in the gas sample - from 0 - 4% perhaps?
None of this, of course, will impact on the AGW hypothesis because, as I have said before, the "radiative imbalance" component is dwarfed by other "known unknowns", but at least it could take some of the speculation out of the radiative physics argument.
rob burton
Locally, I would agree. Look at New York's current situation.
"Analyzing tide-level data from much of North America, U.S. Geological Survey scientists unexpectedly found that sea levels in the 600-mile (1,000-kilometer) stretch of coast from Cape Hatteras (map), North Carolina, to the Boston area climbed by about 2 to 3.8 millimeters a year, on average, between 1950 and 2009.
Global sea level rise averaged about 0.6 to 1 millimeter annually over the same period."
http://news.nationalgeographic.co.uk/news/2012/06/120625-sea-level-rise-east-coast-us-science-nature-climate-change/
EM, how can you explain to yourself that you are curious about a 2 year trend in sea level rise but not at all curious about more than 15 year long stall in temperature rise?
The Milankovitch cycle explanation is - as I have explained to BBD in the past - one of the worst explanations for the glaciations. There are so many problems with it as an explanation in comparison to a stochastic (LTP) explanation. The problems are manyfold:
1. The positive feedback plus Milankovitch cycle explanation requires a linearised model of climate. But we know climate is highly non-linear.
2. There is considerable tuning to make the Milankovitch cycles fit. The ice cores are often orbitally tuned, i.e. dated to ensure the oscillations in the cores match the frequency of the supposedly matching orbital cycles.
3. If tuning the frequency is not enough, the phase of the cycles are also tuned - such as the "insolation at 65N" explanation. This is usually coupled with a bit of hand-waving about the amount of land vs. sea at this latitude. In reality, it is merely another tuning parameter to force a fit.
If we consider a stochastic explanation via LTP for the glaciation cycles, we would expect a power spectral density to have greater amplitudes at lower frequencies. This means we expect amplitudes of 100kyr > 41 kyr > 21kyr for LTP. At much lower frequencies (>> 100kyr) we expect these frequencies to be swamped by lower frequency components (1Myr+).
For the Milankovitch hypothesis, we can fit almost anything in the window 21kyr to 125kyr; there are about half a dozen different cycles that match in this window. But the longest cycles have the smallest forcing, and there are no significant cycles at lower frequencies.
When we look at the data, we see the 100kyr dominating (which in itself makes no sense since there is no peak on 100kyr - there is a 95kyr and a 125kyr which should be resolved but do not). When we go to much longer (> 3 million years), we get lower frequencies dominating - just as we would expect from LTP, but not from Milankovitch forcing.
Given the evidence at hand, a stochastic LTP explanation fits the data far better than the deterministic Milankovitch explanation, even with all of the additional tuning afforded the deterministic explanation.
Worth noting also that the "pause" fits better to a stochastic LTP hypothesis than the deterministic AGW hypothesis. The LTP hypothesis also does not require linearity of the system. It is in every way a more elegant solution that fits the data and our understanding of the system, both in recent instrumental data sets and paleo data sets; but many people have great difficulty accepting stochastic answers over deterministic answers, because they are often viewed as less intuitive as a nice simple cause and effect.
Lay people often mistake cause and effect as being scientific, and stochastics not; in practice, stochastics are more important in science than cause and effect, because they define the limits of measurements and interpretation. If you don't know where your limits are, you may as well be seeing shapes in clouds.
Roger Longstaff
It's an obvious experiment, an extension of what John Tyndall did in 1859. Checking the literature I note that most work is addressed to measuring the RF in the atmosphere, rather than in the lab.
I could not find a paper on this. This could mean that either a) its never been done, or more likely b) its been done so often that it's part of the background knowledge and no longer worth special mention.
It's an easy experiment to do. Any university physics lab should have the equipment. Anyone out there like to try it and report back?
I'm full of satiable curtiosity.
The pause may have one or several causes. Changes in ocean circulation and mixing, man-made and volcanic sulphur aerosols, increased ice melting rates, reduced solar insolation, Dalton mimima, various cycles, etc have all been mentioned as possible contributors. Lots of discussion and papers on the subject, but nothing definitive yet. It's probably several negative forcings pushing temperatures down against the upward pressure from CO2. Losing the GLORY satellite in 2011 was a real blow. It would have given us a lot more data on energy flows, particularly the effect of aerosols.
If the CSU graph is reliable 2011/13 has shown sea level rising three times faster than the 30 year mean and nobody seems interested. If it returns to normal it may be stochastic variation, if not it may indicate a tipping point. Are you not curious to see which way it goes, and why?
spence_uk
The problem with a stochastic process is that it would produce a random pattern of glacial and interglacial conditions. The actual pattern is much more regular, as would be expected if the forcing was cyclic.
EM
When calculated correctly, most of the Milankovitch patterns lie within the CIs of an LTP process, i.e. the pattern is indistinguishable from random chance. It might exceed random chance if it ran for longer, but as we know it completely fails at 3 million years, which should be enough to reject it alone. This needs to be assessed numerically though, not by eyeballing which is highly prone to error (e.g. Wunsch 2004, Markonis and Koutsoyiannis 2013)
As noted, the 100kyr cycle doesn't actually match the frequency it is supposed to be at without orbital tuning to force the frequency to be "correct". These are fundamental problems that are glossed over too easily.
It is very easy to delude yourself into seeing what you want to see, especially with long term persistence which exhibits what is easily mistaken for deterministic behaviour at all scales.
There is some evidence that the 41kyr forcing is above the random variation, but not really the other frequencies (which is in line with the forcing magnitudes). But the 41kyr forcing alone fails to explain the glaciations of the last million years.
The Milankovich pattern fails before 3 million years ago because the forcing only generates glacial periods once the Arctic Ocean becomes sufficiently isolated. At 3 mya Asia, Europe and North America start to close around the Arctic and limit the flow of warmer water from the Atlantic and the Pacific. This allowed latitudes above 50N to cool enough that Winter snowfall no longer thawed in Summer, and the ice sheets spread.
Before then, sufficient heat circulated through the Arctic to prevent ice sheet formation even at minimum insolation and an ice age as we define it now was not possible.
Regarding the 100kyr frequency, remember that you are not looking at one cycle, but three beating at different frequencies. You only get an interglacial when insolation exceeds the threshold value, which may result from one cycle peaking, or the interaction of two.It also affects the timing. For example, if the 41kyr cycle peaks just before the 100kyr cycle it would trigger an interglacial early. If the other cycles bottom out at the same time as the 100kyr cycle peaks, you may not get an interglacial at all.
Is this the "tuning you refer to?
If environmentalism has similarities to religion, the most interesting thing the connection tells us is about man's need to believe. The enlightened West spent much of the last century getting rid of God (often with a sneering contempt). The success of this project has left the vacuum of an unmet need - which many have attempted to fill with eco-nonsense. Like all unmet needs, its presence is felt with an urgency and a conviction of fatality if left unaddressed.
The difference, of course, being that environmentalism is (by its very name) outsiderism... whereas religion placed its central emphasis on the inside. In other words, in seeking to meet a felt need, the environmentalist has absolved himself of any requirement to reflect on its subjective value - and (as we have seen) to studiously avoid others who might do their reflecting for them.
Peter S
Climate scepticism also resembles a religion.
I live in Northern Ireland, which has a useful word : thran.
Depending on your viewpoint it means" persevering in ones opinions" or "pig stubborn".
A typical example of thran would be the fundamentalist Protestant Free Presbyterian who told me "My mind is made up; dont confuse me with facts."
Entropic Man,
I only just saw your response, and was amused by how it read. It very much reminds me of the royal society of physicians defence of bloodletting back in 1871 (article here). An explanation of X causes Y causes Z in a plausible sounding way with absolutely no evidence to support the assertions nor any way of testing the assertions. (See here for another perspective of this phenomenon)
It is interesting because many people have the misguided impression (even within the scientific community - above as an example) that this is what science is about. It isn't. In science, that you can force fit a few crumbs of untestable evidence while ignoring the mountain of contradictory evidence is not considered a good sign in support of your ideas. In fact, it's a pretty good indicator your ideas belong in a bin.
As for the multiplicity of forcings, yes spectral methods should be able to resolve the frequencies between 95kyr and 125kyr but when these methods are applied the "forcings" do not resolve, into different frequencies, showing that the model is not right.
And secondly no, that is not what I mean by orbital tuning, and I find it hard to believe that you try to speak with any kind of authority about Milankovitch cycles without even knowing what orbital tuning is.
97 % of scientists ....
Yes, 97% of government-funded and government-selected scientists say they believe in CAGW and that the role and funding of government should be expanded.
Hats off to the government bureaucrats making the funding decisions.