It's not enough to know something might be a factor, we have to know how the value, too. Some of them, we don't even know the sign.
Even if the earth were as simple as a pan on a stove, predicting an equilibrium temperature, then turning on the gas and getting it repeatably right to 0.5C wouldn't be easy.
Cheers, James Arthur
Not if I were to give value and a tolerance for 'the' temperature. But, that's true of ALL measurement. Value, variance, and units are the scientific measurement trinity, no measurement is complete without all three.
A house is big, and so is a world. Everyone else deals with variations, you seem to think "you're wrong" , i.e. declaring the problem unsolved, is as valid as dealing with it. That's wrong, and you know it.
If your pet theory has to be protected with falsehoods, science offers a solution: euthanize that pet.
But, the other day you were saying 'same as yesterday' was a good model.
Clearly, you have no claim to good judgment of predictive models.
Do you think that your house, or an operating PC board, or a city, is isothermal? Do you think that any of those has one temperature?
Do you think that official weather stations at airports are good to characterize 200-year temperature trends?
-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
No, of course not. No physicist since Maxwell's Demon was first discussed has thought that any ensemble having a temperature was uniform. Since that hasn't been controversial for over a century, I'm confused why you want to discuss it.
Personally, I've never in my life been isothermal.
'Good' isn't testable, make a testable hypothesis, or every scientist knows you haven't asked a reality-based question. Science discards questions that cannot be tested against real world observations.
Characterizing a trend, in weather, uses weather observations. As many as are available. So, 'official weather stations' are accepted, and ubiquitous, and keep detailed long-term records, because that's what weather science consumes in order to grow in knowledge and understanding. Such records might falsify an hypothesis, which would be a knowledge gain. They've falsified one of your pet hypotheses, haven't they?
If your pet theories need the protection of repeated falsehoods, science offers a solution: euthanize that pet.
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.Cite? It is easy to claim that we don't know something when you don't give a specific example. George at least listed a few parameters - you didn't bo ther telling us the one for which we don't even know the sign. Clouds - in fact - go both ways depending on the nature of the clouds involved and wher e they are
"Clouds cause cooling by reflecting solar energy, but they also cause warmi ng by absorbing infrared energy (like greenhouse gases) from the surface wh en they are over areas that are warmer than they are."
That's John Larkin pretending he knows about chaotic systems.
But we do know that if you dump a lot of greenhouse gas into the atmosphere , the surface of the planet gets a lot warmer
The greenhouse gas seems to have been methane rather than CO2, but methane in the atmosphere oxidises to CO2 within a few decades.
-- Bill Sloman, Sydney
Processed properly they are pretty good. Anthony Watts doesn't think so, but his income does depend on spreading denialist propaganda.
-- Bill Sloman, Sydney
Or touch your left elbow with your left hand.
What you've looked at are the source code from a programmer's sandbox released by the Climategate hackers.
You haven't got access to the sort of climate models used by people like Julia Sligo
which can reflect the Chinese monsoon records over the past thousand years, even it can't get the Madden-Julian oscillation quite right.
The one's you could have seen may not be up to much, but they aren't exactly representative of the state of the art.
But what makes you think that the feedbacks are wrong? Water vapour is the big one, and it's relatively simple to model.
And we do have a giant natural experiment to refer to
-- Bill Sloman, Sydney
Does the concept of "more chaotic" mean anything more than "more random"?
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But we do know that it doesn't seem to make much difference.
We've got enough historical/geological evidence to know that more CO2 in th e atmosphere means a warmer climate. Changes in cloud cover might be able t o undo that, but we don't know of any examples where they did.
If you go back a very long way - when the sun was smaller (but no less mass ive) than it is now - you did need more CO2 to get a given temperature, but that doesn't suggest that a change in cloud cover could reverse anthropoge nic global warming.
We certainly do know what it is now - you can sit in your space station and measure how much light is being scattered back at the space station by any place on the surface of the earth.
It obviously varies from place to place - the ocean surface doesn't reflect all that much, and ice sheets and snow cover reflect up to about 90% of in coming solar radiation - and it varies from time to time. Get snow cover wa rm enough to have melt pools and the albedo drops dramatically.
yThe basic principles are clear enough, but temperature is not a simple line ar function of CO2 level in the atmosphere - the relationship is closer to logarithmic - so talking about "sensitivity" as if it is a fixed number bet rays a certain ignorance.
e tThat's a really poor analogy. More CO2 in the atmosphere isn't "a few extra twigs downstream" but a difference that is evenly spread over the whole at mosphere, which raises the effective emission height
What messes this up even more is that water vapour is also a greenhouse gas , but it freezes out into clouds of water droplets (or ice crystals when yo u get higher and colder), so for the IR wavelengths that water absorbs an r e-radiates, the effective emission height is quite a bit lower.
There's also heat transfer within the atmosphere by convection (and condens ing out water vapour dumps the latent heat of condensation into the atmosph ere at the level where the condensation occurs - driving more convection).
The final point is that a lot of the extra heat we trapping with our curren t high CO2 level isn't just warming the surface of the oceans, it's also wa rming the ocean depths. One of the positive feedbacks is that as the ocean depths warm, they lose dissolved CO2, but it takes some 600 to a 1000 years for the ocean depths to fully warm up and dump some of their dissolved CO2 .
At the moment we don't much more about the depths of the ocean than we do a bout the conditions at the bottom of ice sheets - though the Argo buoys are starting to give us data about the ocean depths.
Your "stream" is a lot wider and deeper than your analogy admits.
Predicting how much the a particular rise in CO2 level would eventually rai se the temperature of the surface of the earth isn't all that useful - we n eed to work out how much the temperature will rise over the next few decade s as well.
There's a lot more going on than you would like the reader to think.
-- Bill Sloman, Sydney
Chaotic systems aren't random, but highly determinate. The difficult bit th at they are very sensitive to starting conditions.
John Larkin doesn't know enough about them to say anything sensible, and I don't think he has got the message that the solar system is chaotic, but it happens to take about a millions years for imprecise starting conditions t o show up as hard-to-predict behaviour.
For weather it takes about ten days. Climate is just the integral of weathe r, and the fact that weather follows consistent trajectories with somewhat uncertain timing means that you can predict climate well enough to make far ming practical. John von Neumann demonstrated back in 1956 - with rather ru dimentary computers - that computational models of global weather developed the same features as real weather, with much the same periodicities, even though the "bufferfly effect" - which was known at the time - meant that yo u couldn't predict exactly when the features would show up or exactly how t hey would develop.
-- Bill Sloman, Sydney
Just so.
Hi James, I guess I really don't understand your objections, Let's say that we don't know all the parameters, and may not even have the sign right on some of the one we do know. And even that it's chaotic, (though that part seems less important to me... it's like that guy in the dinosaur movie claiming that chaos is causing the dinosaurs to break loose and go on a rampage... but I digress.) So it's complicated, does that mean we give up and not try to understand it?
Or is your objection that the scientists are corrupt?
Aside, creek analogy: A few twigs are not going to make a difference. However if a tree comes down* that will have an effect. I think that just means we have to adjust our models to new circumstances. Big volcanoes are going to have a big effect on the climate.
George h.
*So trees come down across 'my' creek. But I would find that during the year someone would come by and chain saw all the logs so that they would be swept away in the spring floods... I never understood who did this till I was talking to some local wild water kayakers. It seems that they come by and 'clean up' the creek every year so they can go down it when we have a bunch of rain in the spring/summer. So we can even have human impacts in my creek analogy.Grin back at ya, :^)
GH
Both systems can be described as having a state-change time constant.
The chaotic system can also be characterized by its sensitivities to changes in parameters or external stimuli. That sort of thing can be quantified.
Our planetary system is weakly chaotic; you can predict a planet's location pretty exactly after a hundred orbits, but not forever. Our atmosphere is wildly chaotic, because you can't predict the weather for many days.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
The official San Francisco weather station has been moved six or eight times, generally northeast, more downtown. And downtown is a huge amount bigger (and hotter) than it used to be. And sure enough, we keep hitting high temperature records.
Long term records?
Is this sort of data your idea of settled science?
Not that I know of. Tell me.
If your theories are immune to doubt, and not subject to experiment, you are no scientist.
Are you a scientist?
-- John Larkin Highland Technology, Inc lunatic fringe electronics
No, but we should be cautious about declaring, without a doubt, that we do understand it, and making trillion-dollar decisions based on that belief.
There has been a lot of data fudging, a lot of unscientific bullying, and a lot of failed predictions.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Sure, that's right. (IMO) So let's put up more weather satellites and such. I read this story that there are big LNG tankers from Russia docking in Boston harbor. Why, we've got lots of NG now? It's because we won't build more pipe lines to get the gas to the Northeast. That's dumb. NY banned fracking, that's dumb too.
I'm not sure about lots, but I'd agree with some. I don't know any climate scientists but I would bet most of them are doing their best not to make those kinds of mistakes... the world (or at least Republicans in the US) is/are watching.
And of course now that it's a political football there is all sorts of silliness on the issue, from people who don't know much. (Like you and me... well at least me. :^)
George H.
The anti-fracking, and anti-nuke, positions are absurd. NG and nuclear power both reduce CO2.
Face it, AGW isn't about science, or protecting the planet, it's about politics and power.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Greens can be inconsistent idiots; no news there.
Face it, GW denial isn't about science, or protecting the planet, it's about politics and power.
The financial incentives for denialists are clear.
Skeptics will not gain power, or control over trillions of public dollars, if they prevail. Alarmists will.
Follow the money.
-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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