Nuclear Power at TED Conference

[MSimon]

The Earth has never exceeded 22 degrees, in four billion years, even when CO2 levels were more than ten times higher.

http://www.nature.com/nature/journal/v4 ... 04668.html

OK 23C well within the MOE (re: 22C) for measurements from that era.

We show that sea surface temperatures near the North Pole increased from approx18 °C to over 23 °C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming.

Well well well. Look at the weasel word "imply". And of course it says nothing about ice at higher elevations elsewhere. You would think from the way they are talking that air doesn't circulate.

Don't sceptics do science any more? Or is scepticism the sole province of engineers these days?

[alexjrgreen]

The Earth has never exceeded 22 degrees, in four billion years, even when CO2 levels were more than ten times higher.

http://www.nature.com/nature/journal/v4 ... 04668.html

OK 23C well within the MOE (re: 22C) for measurements from that era.

We show that sea surface temperatures near the North Pole increased from approx18 °C to over 23 °C during this event.

Polar temperatures would normally be below the global average.

[MSimon]

http://www.nature.com/nature/journal/v4 ... 04668.html

OK 23C well within the MOE (re: 22C) for measurements from that era.

We show that sea surface temperatures near the North Pole increased from approx18 °C to over 23 °C during this event.

Polar temperatures would normally be below the global average.

That is a conjecture. Wouldn't data be better?

[alexjrgreen]

OK 23C well within the MOE (re: 22C) for measurements from that era.

Polar temperatures would normally be below the global average.

That is a conjecture. Wouldn't data be better?

Neotropical temperatures of 36 to 37 degrees C for the same period are given here:
http://www.climatechangeandbiodiversity ... amillo.pdf (28/37)

[MSimon]

Polar temperatures would normally be below the global average.

That is a conjecture. Wouldn't data be better?

Neotropical temperatures of 36 to 37 degrees C for the same period are given here:
http://www.climatechangeandbiodiversity ... amillo.pdf (28/37)

The scatter plot looks like about 23C or 24 C for the average. The paper gives 24C.

And then we get into the "climate model predictions". Now the current models are known to be defective. (The oceans are not done well and clouds are a mystery) And then there is the little problem of sparse data for model inputs. Bad now. And it has to be much for data from 50 million years ago.

This paper is based on CO2 causes warming. What if it ain't so (CO2 follows warming is the evidence from the ice cores). And then we have current evidence. CO2 is rising and temperatures have stalled.

Until the models get much better (solar and climate) I'd say that the paper is interesting conjecture. One thing I do agree with - more CO2 is helpful to plants.

One interesting point re: clouds and CO2 it seems like the climate guys love getting cause and effect reversed. If so it changes the sign of the feedback re: clouds and what causes what re: CO2.

[Art Carlson]

One thing I do agree with - more CO2 is helpful to plants.

I'm probably going to regret entering the fray, but it seems you could be a tiny bit bolder. How about, "All other things being equal, adding CO2 to the atmosphere will tend to raise temperatures."? We can argue till the cows come home about how much the effect might be mitigated by feedback mechanisms, and about what others natural and anthropogenic effects might be even more important, but it is simple physics that CO2 reduces re-radiation of energy at relevant wavelengths, and it would be highly unusual if at all possible for a forcing term to produce a net effect in the opposite direction. I mean on the whole, disregarding possible local effects. So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants. I think it is even significantly stronger.

[alexjrgreen]

That is a conjecture. Wouldn't data be better?

Neotropical temperatures of 36 to 37 degrees C for the same period are given here:
http://www.climatechangeandbiodiversity ... amillo.pdf (28/37)

The scatter plot looks like about 23C or 24 C for the average. The paper gives 24C.

If you're referring to the plot on page 5 of 37, 24C is given as the temperature difference above present (14C), ie 38C, during part of the Cretaceous period. This is likely to be a mistake, because the delta 18O figure also varies with global ice volume and the period was glaciated.

The figure for the (unglaciated) Eocene period (just after our polar figures) is given as 12 degrees above present, or 26C. A global average temperature corresponding to the polar figures would be slightly higher.

[djolds1]

I'm probably going to regret entering the fray, but it seems you could be a tiny bit bolder. How about, "All other things being equal, adding CO2 to the atmosphere will tend to raise temperatures."?... So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants. I think it is even significantly stronger.

Warmer, yes. But how much warmer? Evidence I've seen is that additional warming from CO2 falls off on a logistic curve. For every +1 unit of CO2 you get <+1 unit of warming. A minuscule human-caused warming component is just that; minuscule.

[MSimon]

One thing I do agree with - more CO2 is helpful to plants.

I'm probably going to regret entering the fray, but it seems you could be a tiny bit bolder. How about, "All other things being equal, adding CO2 to the atmosphere will tend to raise temperatures."? We can argue till the cows come home about how much the effect might be mitigated by feedback mechanisms, and about what others natural and anthropogenic effects might be even more important, but it is simple physics that CO2 reduces re-radiation of energy at relevant wavelengths, and it would be highly unusual if at all possible for a forcing term to produce a net effect in the opposite direction. I mean on the whole, disregarding possible local effects. So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants. I think it is even significantly stronger.

Yes. I agree that a CO2 doubling would cause a 1 deg. C rise (the consensus value) absent feedback.

Satellite data implies a negative feedback reducing the rise to .5C. System gain .5.

Models assume a positive feedback with the reasonable range considered to be system gain of 1.5 to 4.5.

It all hinges on a few things: was the PDO positive aliased for CO2? What is the actual sign and magnitude of cloud feedback? Why do long term sunspot cycles (Dalton, Maunder Minimums) correlate with large climate shifts. There is a lot of uncertainty and disputation in the first two items. On the third there is ZERO clue. Unless Svensmark with his cosmic rays or Shaviv with his galactic zones gets sufficient backing.

The IPCC has a mandate of imputing to CO2 all unknown forcings. That seems to me a rather unscientific attitude and prone to corruption. i.e. the PDO cycle was known in 1997. As far as I know it was only recently included in ONE model so far. And as far as I know that one model group has not announced a (expected) reduced CO2 forcing as some of the warming would have had to have been unimputed. The attitude is that once the PDO forcing stops temps will roar back. Well yes. the PDO effect in the models would have to be very strong if the CO2 effect is not reduced. And I would expect the models to then show a VERY positive slope at the end of the PDO cycle.

The kicker in all this is that our "constant" sun may not cooperate. Be tough on the modelers if that is so. Fortunately they have bought themselves time with their 2020 prediction.

Lots of fun for all concerned if the government doesn't use this shaky science as a means of robbing us blind. Then we may well see blood in the streets. At least in America where the population is armed and dangerous. It is a good thing every now and then to remind the politicians who their masters are. They have a habit of forgetting their place.

[MSimon]

alexjrgreen,

I have no idea if what you say is true because all we see are pretty pictures. Some one snipped the text.

On top of that models (known to be in error) are used to massage the data.

Now one thing for sure: the models are sensitive to initial conditions. At 50 million years back we can't even impute a century to the data let alone a year. We do not know if variations in the sun's magnetic field have skewed the data ala C14 dating. Nor has any work been done on Shaviv's theories re moving in and out of galactic areas. Things like that could change everything.

But thanks for the pretty pictures . Too bad it wasn't billed as an art piece. The artistry is good.

Also - there are not near enough sceptics in science these days (Art is a good exception at least when it comes to Polywell). That job seems to be left to engineers. Glad to do my part.

[alexjrgreen]

Neotropical temperatures of 36 to 37 degrees C for the same period are given here:
http://www.climatechangeandbiodiversity ... amillo.pdf (28/37)

The scatter plot looks like about 23C or 24 C for the average. The paper gives 24C.

If you're referring to the plot on page 5 of 37, 24C is given as the temperature difference above present (14C), ie 38C, during part of the Cretaceous period. This is likely to be a mistake, because the delta 18O figure also varies with global ice volume and the period was glaciated.

The figure for the (unglaciated) Eocene period (just after our polar figures) is given as 12 degrees above present, or 26C. A global average temperature corresponding to the polar figures would be slightly higher.

I was wrong. The original paper by Zachos is here:

http://earthscience.ucr.edu/gcec_pages/ ... Trends.pdf

and the 12C should be read as the global average. That makes the 24C from Huber's paper more reasonable.

Deep-sea paleotemperature record of extreme warmth during the Cretaceous
Brian T. Huber, Richard D. Norris and Kenneth G. MacLeod
Geology; February 2002; v. 30; no. 2; p. 123-12

[TDPerk]

So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants.

To propose a mechanism which makes this out to be a naive assumption: CO2 in greater concentrations traps impinging solar energy at thermal wavelengths in greater concentrations at the altitudes at which it is intercepted. When atmospheric CO2 increases, in the then relatively smaller areas which receive full sunlight, disproportionately more water vapor is produced from water covered areas, which diffuses to other, higher, colder altitudes such that it condenses and in net reduces the average temperature of the earth--the warm areas are much warmer, but the rest of the planet is colder, and on average more cold overall.

It does imply more locally violent weather as local temperature imbalances move towards equilibrium.

It is a great weakness of the AGW crowd that they have no models which speak reliably to the possibility,let alone no models which reproduce the past from the data, without their being invalidated when the data is revised.

We need robust models before we just do something instead of standing there.

Yours, TDP, ml, msl, & pfpp[/quote]

[Art Carlson]

So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants.

To propose a mechanism which makes this out to be a naive assumption: CO2 in greater concentrations traps impinging solar energy at thermal wavelengths in greater concentrations at the altitudes at which it is intercepted. ...

Hold it right there. The things I don't know about climatology would fill libraries, but I think I do understand the basic greenhouse mechanism. CO2 is transparent in the visible so it doesn't absorb much "impinging solar energy" at all. It's by absorbing the energy re-radiated by the Earth at thermal wavelengths that CO2 contributes to warming. There may be a mechanism that trades extreme local warming against global cooling, but I have never seen it and can't imagine it myself.

[glemieux]

Wow, guess I stirred something up . I just want to point out that my intention was to discuss the talk's internal merits, not necessarily the baseline assumptions. Perhaps I should have put this in the general section....

[TallDave]

So the conclusion that the CO2 we are adding to the atmosphere is making the world warmer than it would be otherwise seems at least as solid as your statement that CO2 helps plants.

To propose a mechanism which makes this out to be a naive assumption: CO2 in greater concentrations traps impinging solar energy at thermal wavelengths in greater concentrations at the altitudes at which it is intercepted. ...

Hold it right there. The things I don't know about climatology would fill libraries, but I think I do understand the basic greenhouse mechanism. CO2 is transparent in the visible so it doesn't absorb much "impinging solar energy" at all. It's by absorbing the energy re-radiated by the Earth at thermal wavelengths that CO2 contributes to warming. There may be a mechanism that trades extreme local warming against global cooling, but I have never seen it and can't imagine it myself.

Yes, that's actually one of the problems with the models. If CO2 drives temps in any meaningful fashion (and there are strong historical reasons to think it does not), the mechanism should do so in a predictable way: mid-tropospheric warming and stratospheric cooling. The fact we don't see that suggests any warming we are experiencing has little to do with CO2.

This is sort of like the difference between beam-beam fusion and beam-background fusion. You would want to be skeptical of people claiming significant consequences (i.e., scaling to net power) based on an assumption their experiment is recording beam-beam fusion, if upon closer evaluation the experiment turns out to have all the characteristics of beam-background.