If NASA scientists are right, the Thames will be freezing over again.

It was never about science. It was all about power and the redistribution of wealth.

ion of wealth.

That may be all you want to see in it, but that is a rather short- sighted point of view.

The reality is that the earth has already warmed by about 0.8=B0C over the past century. Atmospheric CO2 levels have risen from about 270ppm before the industrial revolution to some 315ppm when we first started measuring them accurately in 1958 to to 387ppm at present.

Correlation isn't causation, but we do have a fairly clear idea of how rising CO2 levels make the earth's surface temperature rise, and no explanation of the 0.8=B0C temperature that doesn't involve increased greenhouse warming from the extra CO2 looks remotely plausible.

If we keep on pumping CO2 into the atmosphere at an every increasing rate, global temperatures are going to rise quite a bit more, which seems unlikely to do as any good at all.

Simple prudence suggests that we should slow down on burning fossil carbon to generate energy, and move over to renewable energy sources as fast as possible. This is going to cost money, but nothing we can't afford - at the current extra cost of renewable energy an immediate switchover would set the global economy back by a couple of years worth of normal economic development.

Since it would take us a decade or two to build enough renewable generating plant to replace existing power stations, we really wouldn't notice that energy had gotten more expensive, and the steadily rising price of fossil carbon - which isn't a renewable resource and is getting progressively more expensive to dig up as we get through the more accessible deposits - and the economies of scale involved in building really extensive renewable energy generating plant will almost certainly mean that renewable energy will be the cheaper option whenever we get around to building enough plant to replace a significant proportion of the fossil-fuel-based plant.

The only people who object to this logic are the guys who are making a lot of money out of digging up fossil carbon and selling it as fuel. They seem to figure that they are all going to be dead before anything serious happens, and that they will be able to accumulate enough money to let their kids buy their way into some sort of safe haven when climate change does go from an inconvenience to a real threat.

Jahred Diamond's book "Collapse: How Societies Choose to Fail or Succeed". New York: Viking Books. ISBN 1-586-63863-7 makes it perfectly clear that the top dogs in any society under threat will concentrate on remaining top dogs as their society disintegrates around them. It's going to take an effort to get them to behave more responsibly.

-- Bill Sloman, Nijmegen

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I used to read RSI whan I was a kid, working summers (microwave spectroscopy and nuclear instrument design) at LSUNO, where the "library" (actually a trailer) had the hardcopy version.

A couple of years ago I had online access (paid!) to RSI so I culled the past few decades of good stuff, which turned out to be not much. The electronics tends to be somewhere between primitive and dreadful.

I can go to the nearby Mission Bay campus of UCSF and look up RSI, and other journals, there for free, and print stuff for $1 a page. I do that occasionally, specifically when I have some new science to instrument.

particular group or organization[1]."

much so that you ignore all evidence which conflicts with it and try to pretend you are the only scientific ones.  There is no science but your science.

grounds  (Merriam-Webster)

incredibly egotistical and semi-hysterical to believe they can determine the climate.

I rarely breadboard, and that's mostly to characterize parts that are inadequately specified, or sometimes to play with a fun circuit. We never prototype, because that wastes time and teaches bad habits. Our products are designed, formally released, and built by manufacturing, and most of the time we can sell rev A, the first release.

We don't do a lot of Spice simulation either, because we design things that will work. What does take a lot of time is FPGA workbenching, which makes sense because FPGA designs are usually very complex and you can't easily probe the guts of an FPGA to find out what's wrong.

I did fix a real stumper yesterday, on a laser controller we're doing. My guys are coding both ends of a 32-bit ARM-to-Xilinx memory-mapped interface and three of the bits were weird. The ARM would always read back whatever it last wrote to the FPGA, on three bits out of 32, bits

So I fortified myself with chocolate and opened the ghastly 1200-page NXP LPC3250 manual, the trick being to ignore the big print and look for the tiny footnotes where they hide the real horrors. Bingo, those three bits have alternate/multiplexed functions having to do with one DDR DRAM mode, and the ARM setup code somehow enabled the 32 bit data bus *and* the 16-bit DRAM mode... one bit in some obscure register set wrong, three man-days wasted. NXP lets things like that happen.

Maybe Google will index this, and somebody with the same problem will trip across it.

I've published at least one comment there saying pretty much exactly that about a specific paper

and I've published comments that are only slightly less disparaging about a couple of others. The referees they use for electronics-based papers don't always seem to be all that good.

See if you can find somebody who subscribes the the British "Measurement Science and Technology" published by the British Institute of Physics. It seems to publish a bit more stuff from industry, and the electronics isn't usually too bad.

-- Bill Sloman, Nijmegen

I hadn't forgotten, I was just talking about hydrostatic equilibrium. And whatever the merits of Darwin's work (his reputation in philosophical circles is not very high just now AIUI), he was personally a bit of a git. (The Geological Society produced a fair number of those round about that time--if you haven't read Martin Rudwick's book, "The Great Devonian Controversy", I highly recommend it. A classic of the history of science, and enormous fun besides.)

That's a bit of an overstatement, I think. In broad averages, the hydrostatic solution has to work--there's nothing that's going to change the mass of a proton or the charge on an electron, and the calculation of luminosity on the basis of stellar mass and composition is pretty fundamental stuff. (You can argue about the treatment of metals, but that's a second order effect anyway.) So over timescales comparable or longer than the thermal time constant of the Sun, I entirely agree.

But the topic came up in regards to things like the Maunder minimum, which was only 300 years ago. That's long compared with the acoustic timescale, but short compared with the thermal time scale. Our satellite data span what, 10% of the time since then? I'm not saying that I have a good mechanism for larger variations, but who knows? Stars do funny things sometimes.

Jason got his Ph.D. in 1965, for doing a reasonably complete numerical model of the Sun. I'm sure there were a fair number of people involved--it was one of the pressing problems of the day. I haven't seen his thesis, or read any of the other folks' stuff. I was mostly passing on content from the class. (It was my favourite astronomy class, closely followed by celestial mechanics.)

The measured changes do, I agree, but the very short data set we have available doesn't prove that the Maunder minimum wasn't associated with a century or two of lower solar output. Annual variation is too fast and equinoctial procession is too slow to fit. Anyway, that wasn't what I was mostly on about.

Mostly I was subjecting Bill to mild ridicule for saying that it was unscientific to believe stellar models, when he believes climate models, which contain far more in the way of fudge factors and parameter fitting.

Cheers

Phil Hobbs

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If you want to propose a century or two of significantly reduced solar output, you've got to find a plausible place to store the extra heat that isn't getting out. Got any suggestions?

Which isn't what I'd said; I was objecting to the proposition that anybody had claimed absolute stability in solar output on the basis of a theoretical model. The theoretical model doesn't leave a lot of room in which to store energy so that you can get fluctuations in the rate of delivery of energy that is being produced by a fusion process that is taking place in the core of the sun, a long way from anything that might perturb the fusion process, but the sun's convection layer was known to be turbulent pretty much as soon as anybody had worked out that it had to exist, and turbulence should have suggested some small scale variation.

The climate models required to validate anthropogenic global warming aren't that complicated. The models required to predict how bad it will be are more complex, and those required to predict how climate change will screw up local weather conditions and agricultural productivity are worse again. This doesn't mean that we ought to ignore the problem until it is bad enough to make the modelling is simpler.

Before you get too enthusiastic about using the Maunder Minimum to explain the Little Ice Age, you may want to read

which explains it in terms of no less than four substantial volcanic eruptions which produced significant and sustained growth in the northern ice cap.

"The persistence of cold summers is best explained by consequent sea- ice/ocean feedbacks during a hemispheric summer insolation minimum; large changes in solar irradiance are not required."

It showed up on the science page of the Volkskrant today - on the web- site the paper is still in press, but google shows up quite a few references to it.

-- Bill Sloman, Nijmegen

So how big a factor is the low level of volcanism since Krakatoa?

BTW, what do you think of Lomborg?

Some of Darwin's supporters were worse and cartoonists had a field day!

But his basic hypothesis and the observational foundation was sound.

I'd be wary of claiming universal constancy of output from stars in all cases. A proportion of stars are variable and some like Cepheids and RR Lyrae have periods that are determined by their absolute luminosity. The solution may be OK on average but if it bounces around the equilibrium it doesn't have to be constant. They provide excellent standard candles for local galaxies now as Henrietta Lovett first observed. For anyone interested:

And even when we think we know how they behave there are still minor twists and turns.

And the sun itself is a bit quirky when you really look up close with modern instruments. I can't find the latest but this will do:

No disagreement there and on the face of it there is now evidence that lack of sunspots and consequent changes in UV output can alter the position of the jetstream making Northern Europe colder in winter. Not necessarily global cooling but locallised in highly populated areas.

There is no doubt that an active sun also fluffs up and dumps energy into the thermosphere (mainly causing extra drag on satellites) but it might also play a very small part in warming the Earth. The pure TSI change on its own is too small to explain the periodic variation in temperature so some additional feedback must occur on the Earth.

But the recent warming occurred during a period where there was good satellite monitoring of TSI so magic hand waving will not hack it.

I rather liked the idea that more massive stars burn much faster. Essentially since a bigger volume inside them met the conditions for fusion and the surface area for light to escape from scales as r^2.

I agree there is a distinct possibility that some of what we see as climate change on Earth is due to changes in the sun (roughly about half of what has been observed since 1850). Certainly during the Maunder minimum there is a real possibility that solar TSI was lower although Keeling and Whorf offer another explantion that I personally find more appealing - that the tidal influence of the Sun-Moon-Earth system has certain key periodicities which seem to be reflected in climate data.

Whilst I have technical reservations about parts of their analysis (notably how they isolated the decadal variation) I think they might be onto something. Unfortunately the non-linear coupled oceanic circulation model folk are all in vogue to explain this at the moment.

Although they do include adjustable parameters you must know as well as I do that in astrophysics it is just the same but you don't get many fossil fuel lobbyists complaining about relativistic jets in distant galaxies, cold dark matter or dark energy. I find the latter much harder to accept since it was discovered long after my involvement. YMMV

Regards, Martin Brown

Interesting stuff, Martin, thanks.

Cheers

Phil Hobbs

What's the matter Bill? Things hitting to close to home lately?

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Not that I've noticed. And you don't qualify as thing - if you were harbouring any delusions about your own status - and barely even qualify as an object of derision.

Apologies to the usegroup for giving this much attention to the twit.

-- Bill Sloman, Nijmegen

I am glade you apologized to the group, it is only a small step but at least you're starting to get it.

Maybe somewhere along the lines, you may even start admitting to be misinformed, about many things.

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On those rare occasions when I have proved to be misinformed, I do admit it. One of the reasons that I post here is that it tests the state of my knowledge. You - on the other hand - don't know much, a lot of what you think you know isn't so, and you show no capacity for becoming better informed. To cap it all, you are so unaware of your ignorance that you presume to tell me that I'm misinformed on many subjects.

Thanks for the moment of amusement. I hope the rest of the group finds it equally funny.

-- Bill Sloman, Nijmegen

simple

I guess your method of testing has failed ^^^^^^^^^^^^^^^^^^^^^^^^^^^

But like you said above, you test your knowledge. Your test has failed you grossly.. Like I said before, misinformed.

Didn't your mother tell you to believe half of what you see and nothing of what you hear?

Jamie

Some of the rivers are already in the process of freezing over:

particular group or organization[1]." =20

much so that you ignore all evidence which conflicts with it and try to = pretend you are the only scientific ones. There is no science but your = science.

grounds (Merriam-Webster)

incredibly egotistical and semi-hysterical to believe they can determine = the climate.

Target approved, bomb away.

?-)

So, hell really can freeze over. :)

Cold enough here that watefalls have frozen

Ice skating in the fens in Eastern England and -22C reported in the Netherlands.