Climate Change - The Scientific Debate (Vol. II)

[Atomic12C]

Gandahar said:

Good posts

"but the human influence is being wildly over-estimated in climate models, and therefore the science behind why the globe has seen a temperature rise since the industrial revolution is flawed."

So far the PH TVR V8 drivers on here have failed to show this is false. And not likely to to any time soon.

Happily be corrected....
Is it not the case though that climate modelling does not follow ongoing observations?
Wasn't it Al Gore that said we'd all now be in a run-away catastrpophe situation by 2020 with already miillions of dead who lived near the coast and a 2m sea level rise?

So maybe not the PH V8 posters, but the failing of the climate consensus to show that their models predict accurately using the theory that is given to politicians?

[Jinx]

hairykrishna said:

The water absorption thing again.

As always I urge anyone with a science background to read the Physics Today article from a few years ago where Prof. Pierrehumbert sets out the basics of the IR greenhouse effect; https://geosci.uchicago.edu/~rtp1/papers/PhysToday...

Until you're at least the level of understanding imparted by that article there is no point in you debating about IR absorption in the atmosphere because you have no idea what you're talking about.

There is nothing in that article that contradicts my comment - it is a very narrow band of IR that CO2 absorbs. I have not claimed that CO2 is saturated at that band just pointing out that the IR spectrum is a lot wider. That article claims that "The CO2 greenhouse effect is directly visible in satellite observations of the bite taken out of the IR spectrum near 667 cm^(-1)"
And goes on to claim that the width will increase as CO2 increases.
I say no it isn't. H2O (as vapour) as shown in figure 1 also absorbs in the in the 667 (bottom right figure - H2O spikes at 668-670) and to assume that the CO2 spike at magnitudes of molecules less than H2O (can be easily 4% of the atmosphere vs 0.04%) is the cause of the dip is a jump in logic and unsupported.
Note - figure 3 is a mix of models, calculations and measurements (would have been nice to have a like with like for the planets rather than a mix of summer (Mars) and night (Venus) and AIRS.
How much energy is at the 667 cm^(-1)? Approx 0.04 W/m^2 by eyeballing the fig 3 graph. How much does Hansen et. al give the imbalance? 0.58 W/m^2 (+-0.15 W/m^2) (2005-2010)
So where does this extra magnitude of energy come from? If only we could harness this magical 0.54 W/m^2 of freely created energy we could get our perpetual motion machines working.....

[Jinx]

hairykrishna said:

Take the 'controversial' tree ring data out. Still get a hockey stick from other temperature reconstructions.

The McIntyre and McKitrick criticism has been picked apart plenty of times; 'has been shown to produce a hockey stick from random noise' is not accurate.

The other "reconstructions" need to stand on their own merits. Ergo all tree ring based temperature proxies need to be removed and the papers that depend on them (or reference them) need to be either thrown out or re-evaluated. Also any hockey sticks that splice thermometer records at a high resolution onto proxy data at low resolution without at least reducing the high resolution data to a lower resolution need to be thrown out as bad practice.

[Toltec]

Flibble said:

A better graph is this:



Notice how CO2 covers quite a large portion of the effective window (i.e. the portion that is relevant for ground emissions), despite being a small amount of the total blocked by water.

Just a minor point, the lack of vertical range numbering on the top graph rather hides the fact that a different scale is being applied to the downgoing and upgoing portions of the graph.

[Flibble]

Toltec said:

Just a minor point, the lack of vertical range numbering on the top graph rather hides the fact that a different scale is being applied to the downgoing and upgoing portions of the graph.

Does it matter? The intention is not to compare absolute energy amounts, but to compare the proportion of each being absorbed by the atmosphere.

[Toltec]

Flibble said:

Toltec said:

Just a minor point, the lack of vertical range numbering on the top graph rather hides the fact that a different scale is being applied to the downgoing and upgoing portions of the graph.

Does it matter? The intention is not to compare absolute energy amounts, but to compare the proportion of each being absorbed by the atmosphere.

I guess it only matters if you want to know what effect it has on the total energy balance, but if you just want a cool looking graph it is fine.

I'll leave my cool graph too.

[Flibble]

Toltec said:

Flibble said:

Toltec said:

Just a minor point, the lack of vertical range numbering on the top graph rather hides the fact that a different scale is being applied to the downgoing and upgoing portions of the graph.

Does it matter? The intention is not to compare absolute energy amounts, but to compare the proportion of each being absorbed by the atmosphere.

I guess it only matters if you want to know what effect it has on the total energy balance, but if you just want a cool looking graph it is fine.

I'll leave my cool graph too.

It was to show the overlap of the emission spectrum of Earth and the CO2 absorption spectrum, not to compare the Sun with the Earth.

But you crack on with your cool graph, which shows a completely different set of data.

Since you're going to be needlessly obtuse, here you go:

[Jinx]

Flibble said:

It was to show the overlap of the emission spectrum of Earth and the CO2 absorption spectrum, not to compare the Sun with the Earth.

But you crack on with your cool graph, which shows a completely different set of data.

Since you're going to be needlessly obtuse, here you go:

Since we are all posting images - here's an accurate one for CO2

]

[PRTVR]

hairykrishna said:

The water absorption thing again.

As always I urge anyone with a science background to read the Physics Today article from a few years ago where Prof. Pierrehumbert sets out the basics of the IR greenhouse effect; https://geosci.uchicago.edu/~rtp1/papers/PhysToday...

Until you're at least the level of understanding imparted by that article there is no point in you debating about IR absorption in the atmosphere because you have no idea what you're talking about.

Right, I am not a scientist but read the article, nothing new, he talks about filling the gaps, if that was the case there would be saturation at some point, if not we would have hot spots around areas of high CO2, this we do not have, so is the saturation level very low ?

[hairykrishna]

Jinx said:

hairykrishna said:

The water absorption thing again.

As always I urge anyone with a science background to read the Physics Today article from a few years ago where Prof. Pierrehumbert sets out the basics of the IR greenhouse effect; https://geosci.uchicago.edu/~rtp1/papers/PhysToday...

Until you're at least the level of understanding imparted by that article there is no point in you debating about IR absorption in the atmosphere because you have no idea what you're talking about.

There is nothing in that article that contradicts my comment - it is a very narrow band of IR that CO2 absorbs. I have not claimed that CO2 is saturated at that band just pointing out that the IR spectrum is a lot wider. That article claims that "The CO2 greenhouse effect is directly visible in satellite observations of the bite taken out of the IR spectrum near 667 cm^(-1)"
And goes on to claim that the width will increase as CO2 increases.
I say no it isn't. H2O (as vapour) as shown in figure 1 also absorbs in the in the 667 (bottom right figure - H2O spikes at 668-670) and to assume that the CO2 spike at magnitudes of molecules less than H2O (can be easily 4% of the atmosphere vs 0.04%) is the cause of the dip is a jump in logic and unsupported.
Note - figure 3 is a mix of models, calculations and measurements (would have been nice to have a like with like for the planets rather than a mix of summer (Mars) and night (Venus) and AIRS.
How much energy is at the 667 cm^(-1)? Approx 0.04 W/m^2 by eyeballing the fig 3 graph. How much does Hansen et. al give the imbalance? 0.58 W/m^2 (+-0.15 W/m^2) (2005-2010)
So where does this extra magnitude of energy come from? If only we could harness this magical 0.54 W/m^2 of freely created energy we could get our perpetual motion machines working.....

I didn't post the article to directly contradict any points you had made. My comment was that, until you understand the physics to at least the base level of that article, there's no point spending time debating with you about IR transport. The reason being that you will keep making arguments that are physically incorrect.

You haven't understood the point about effective emission heights and the role of water vapour vs CO2.

You seem to be 'eyeballing' a graph of the earths TOA radiance, i.e. watts per steradian per square metre, picking a number for a single wavelength and comparing this number to Hansens calculated total average flux imbalance. 'Not even wrong' is the phrase that comes to mind.

[Gandahar]

While you have all been fannying about arguing over a graph.... here's another one


Current Antarctic sea ice extent lowest on modern day sat record




Global ice extent record might fall too in the next couple of days....

Edited by Gandahar on Saturday 8th September 17:37

[micky g]

And in 2014 it was a record high.

Short term changes prove what exactly?

[PRTVR]

Gandahar said:

While you have all been fannying about arguing over a graph....


Current Antarctic sea ice extent lowest on modern day sat record

And 2014 looks the highest, do you think we can read anything into the numbers ?

[Gandahar]

Atomic12C said:

Gandahar said:

Good posts

"but the human influence is being wildly over-estimated in climate models, and therefore the science behind why the globe has seen a temperature rise since the industrial revolution is flawed."

So far the PH TVR V8 drivers on here have failed to show this is false. And not likely to to any time soon.

Happily be corrected....
Is it not the case though that climate modelling does not follow ongoing observations?
Wasn't it Al Gore that said we'd all now be in a run-away catastrpophe situation by 2020 with already miillions of dead who lived near the coast and a 2m sea level rise?

So maybe not the PH V8 posters, but the failing of the climate consensus to show that their models predict accurately using the theory that is given to politicians?

Good post. So in summary politicians and what is fed to them is as bad as laymen, V8 or humble 4 pot diesel varieties.

What winds me up though is people on here saying, in effect, the scientists are wrong. Just down to a feeling....

We just don't chuck in religion now to really put them down, like we did in the old days

[Gandahar]

PRTVR said:

Gandahar said:

While you have all been fannying about arguing over a graph....


Current Antarctic sea ice extent lowest on modern day sat record

And 2014 looks the highest, do you think we can read anything into the numbers ?

Very good point!

No.

Long term trends are what matter.

[PRTVR]

Gandahar said:

PRTVR said:

Gandahar said:

While you have all been fannying about arguing over a graph....


Current Antarctic sea ice extent lowest on modern day sat record

And 2014 looks the highest, do you think we can read anything into the numbers ?

Very good point!

No.

Long term trends are what matter.

Looking at the top the 10 year trend appears to show an increase, but the 10 million dollar question is, what is long term.

[Atomic12C]

Gandahar said:

Good post. So in summary politicians and what is fed to them is as bad as laymen, V8 or humble 4 pot diesel varieties.

What winds me up though is people on here saying, in effect, the scientists are wrong. Just down to a feeling....

We just don't chuck in religion now to really put them down, like we did in the old days

I've been watching a few youtube vids of various psychology and social acceptance of 'MMGW' and it is interesting to see how confirmation bias is at play.... not only if one views it from the non-acceptance side of the argument but also strongly for those that blindly accept it too.

It is a very polarising issue. With large influential advocates on either side.


The debate is obviously an ongoing one, but I think there is a failure on both sides to keep things 'simple' and not to confuse everything with endless manipulated graphs and pages of adjusted data that is aimed at advocating a particular aspect of the observation.

For me the accuracy of the science falls back on the scientific method.... that being if the predictions accurately match observations.
Of course the time scale for climatology plays out over a long time in comparison to many other sciences, but all the same as time goes on we have all the predictions from the start of the 2000's leading up to current day. If the predictions are constantly inaccurate then there is nothing more than politics at play. However if the predictions are very much within a fraction of a percent, then the modelling and the theory of what is happening should be accepted.


This is where I'd happily be corrected, as I've not followed the in-depth discussions nor all the particular aspects of what is being measured and what is predicted about them, but on the whole (to ask this thread in general) is the predicted temperature of the globe following the emprical measurements to the letter or not?

Or are we finding that the prediction models are constantly having to be modified or have to contain an amount of 'political' interpretation in order they fit accurately?

For me the whole debate as to whether climatology on MMGW is science or politics hangs around that.

[durbster]

Atomic12C said:

... we have all the predictions from the start of the 2000's leading up to current day. If the predictions are constantly inaccurate then there is nothing more than politics at play. However if the predictions are very much within a fraction of a percent, then the modelling and the theory of what is happening should be accepted.

I don't think anybody expects a model of the earth's atmosphere to be that accurate. It's far too complex a system for that and it's impossible to know how much CO2 (and other greenhouse gases) will be in the atmosphere in x years, let alone natural events like volcanoes. The earth is not a constant state at all, so precise predictions are highly unlikely.

All the models can do is make an informed guess at the long term trend.

Nobody expects them to be perfect, or treats them as such (unless you're arguing against AGW and need a strawman ).

Atomic12C said:

This is where I'd happily be corrected, as I've not followed the in-depth discussions nor all the particular aspects of what is being measured and what is predicted about them, but on the whole (to ask this thread in general) is the predicted temperature of the globe following the emprical measurements to the letter or not?

To the letter, no of course not, but basically they've all been on the right track:
https://www.yaleclimateconnections.org/2017/10/how...

Atomic12C said:

Or are we finding that the prediction models are constantly having to be modified or have to contain an amount of 'political' interpretation in order they fit accurately?

As computing power increases and more data becomes available, obviously you would modify the models to try and make them more accurate.

[robinessex]

durbster said:

Atomic12C said:

... we have all the predictions from the start of the 2000's leading up to current day. If the predictions are constantly inaccurate then there is nothing more than politics at play. However if the predictions are very much within a fraction of a percent, then the modelling and the theory of what is happening should be accepted.

I don't think anybody expects a model of the earth's atmosphere to be that accurate. It's far too complex a system for that and it's impossible to know how much CO2 (and other greenhouse gases) will be in the atmosphere in x years, let alone natural events like volcanoes. The earth is not a constant state at all, so precise predictions are highly unlikely.

All the models can do is make an informed guess at the long term trend.

Nobody expects them to be perfect, or treats them as such (unless you're arguing against AGW and need a strawman ).

Atomic12C said:

This is where I'd happily be corrected, as I've not followed the in-depth discussions nor all the particular aspects of what is being measured and what is predicted about them, but on the whole (to ask this thread in general) is the predicted temperature of the globe following the emprical measurements to the letter or not?

To the letter, no of course not, but basically they've all been on the right track:
https://www.yaleclimateconnections.org/2017/10/how...

Atomic12C said:

Or are we finding that the prediction models are constantly having to be modified or have to contain an amount of 'political' interpretation in order they fit accurately?

As computing power increases and more data becomes available, obviously you would modify the models to try and make them more accurate.

1. Models have miserably failed to predict anything you could call accurate
2. Fiddling with models until they give you the answer you want is as good as guessing.

PS. No one knows whether a slight rise in the planets temperature (whatever that is) is good or bad. Maybe we ought to concentrate on that first

[PRTVR]

durbster said:

Atomic12C said:

Or are we finding that the prediction models are constantly having to be modified or have to contain an amount of 'political' interpretation in order they fit accurately?

As computing power increases and more data becomes available, obviously you would modify the models to try and make them more accurate.

No problems with that, but first accept that we are not at the stage political decisions should be based on inaccurate predictions.