What is the real LED energy efficiency?

[Chris Hogg]

There was this: "Carbon dioxide causes about 20 percent of Earth?s greenhouse effect; water vapor accounts for about 50 percent; and clouds account for 25 percent." It then went on to say "when carbon dioxide concentrations rise, air temperatures go up, and more water vapor evaporates into the atmosphere ? which then amplifies greenhouse heating".

But water vapour has always been present in the atmosphere. If CO2 causes the atmosphere to warm, which in turn increases the water vapour content and results in yet more warming, the same is true for water vapour on its own. A small amount will cause the atmosphere to warm a little, resulting in more water vapour, causing more warming, until you get thermal runaway and it gets very warm indeed, a bit like Venus.

But that doesn't happen, so why should it happen with CO2? I don't see that water vapour being condensable while CO2 isn't, makes any difference.

[RJH]

Why don't you just contact them and ask? I don't think anybody on this NG has enough of a grasp of the science . . .

[Chris Bacon]

Why have you completely misread the article? I suggest you re-read it, more carefully.

[Chris Bacon]

You don't need much of a grasp of science, jus the basicsand a willingness to red and *think*, an ability that seems sadly lacking.

[Chris Bacon]

I very much doubt that. Which lectures, precisely? They can be viewed online, so I would like to know.

[The Natural Philosopher]

truly scary.

[The Natural Philosopher]

Calorific value of a corpse isn't great sadly, or we would have combined cycle gass crematoria power stations.

[The Natural Philosopher]

NASA run on gummint funding. They wont contradict the Party Line. When you find websites that ought to be authoritative like the met office, the BBC or NASA spouting palpable nonsense, you know there isn't much hope

[The Natural Philosopher]

The doublethink is frightening.

What the proposition is, is that any temperature change is amplified by positive feedback. ANY temperature change, Volcanoes - anything.

I read a paper that said when stripped down to basics

'we looked at the change in radiation caused by a major volcanic eruption and found that it absolutely agreed with recorded temperature drop, which proves that the radiation drop/ temperature drop is valid, then we took that figure MULTIPLIED IT BY THE FEEDBACK and showed that modern climate change was due to CO2!!!!'

But they *never* multiplied the climate change due to the volcano, by the feedback.

And yet that is what is supposed to happen - any change in temperature due to a change in radiation is multiplied by the feedback. Unless its Pinataubo, when it isn't. To make the data fit the CAGW theory!

What they had done is utterly disprove the CAGW narrative, and yet they claimed their results supported it.

[The Natural Philosopher]

I think that far too many people at NASA don't have a grasp of the science or the mathematics.

That is the trouble. Too narrow specialisations.

Climate science so called is a mixture of physics chaos mathematics, statistics, computer modelling and downright fudging.

Very few people exist who understand, or have the time to understand, more than one bit of it.

Even fewer are going to risk their jobs over it.

[newshound]

I was *very* irritated by the recent BBC "Climate Question" episode subtitled Putin and the Planet. That part was OK, but they had a filler at the end on some Finnish research that had discovered a negative feedback term in forest chemistry. They said, quite without irony, that we normally only hear of positive feedback effects in the climate debate.

My email to them asking whether anyone on the production team had actually ever heard of James Lovelock was probably a bit too ranty for me to expect a response.

[Chris Hogg]

It was a rhetorical question. The fact that water vapour doesn't cause thermal runaway in the global temperature means there must be negative feedback in there somewhere, so where is it and what causes it? The simple answer is clouds. The more water vapour in the atmosphere, the greater the propensity for cloud formation. Although clouds trap heat beneath them (you generally don't get frost on cloudy nights, only on clear nights), they also reflect the sun's incoming energy and prevent it reaching the earth's surface, so preventing that surface from warming (it's bloody hot in a desert with no clouds in the sky above you). It's a balance, or actually an imbalance. Although nearly all the global temperature models assume clouds cause positive feedback, trapping more heat than they block coming from the sun, that doesn't make sense. There has to be negative feedback otherwise we'd have had thermal runaway squillions of years ago, long before man ever appeared on the earth, let alone before he started burning fossil fuels and producing CO2.

More discussion here:

[Vir Campestris]

I think you'll find the efficiency is **** awful. For a start they reflect most of the green, and don't use it.

However as they are self assembling they still have a useful impact.

Andy

[Chris Hogg]

Quite, which is why leaves are mostly green. Chlorophylls absorb mostly in the blue and in the red.

[RJH]

Ah OK. I think the confusion/disagreement related to your rhetorical question and answer lies in the notion that vapour is an effect of temperature change, and not a cause.

But I have very little knowledge of climate science. You obviously do - far beyond that of many other climate science postdocs it seems.

Do you happen to think that any focus on reducing CO2 output is misplaced?

That seems to be saying 'clouds matter'. No argument from me.

[RJH]

Very good reasons for that - reasons that you, as a solid physicist and climate science expert will doubtless recount . . . ;-)

[RJH]

'Don't know' then?

[RJH]

It's difficult to establish what you think on this topic, or why. But in essence I take you disagree with pretty much all of the originally linked article:

because of the 'trouble of narrow specialisations'?

So. Why don't you write to them with your corrections, rather than peddle your theories on a backwater NG?

Take this section:

[Chris Hogg]

It is both an effect and a cause, not an either/or. The article linked to above says it causes about 50% of the Earth's greenhouse effect. It is a greenhouse gas (GHG) in its own right. If the global temperature goes up, for whatever reason, whether a greenhouse effect due to CO2 or to water vapour, the water vapour content of the atmosphere will rise, so increasing the greenhouse effect yet further (that article says so). It's positive feedback. So why didn't the Earth see the effects of this superabundant and self-increasing GHG millennia ago? Because something held it back, and that something was negative feedback due to clouds. That particular negative feedback will work just as well for warming due to CO2 as it will for warming due to water vapour.

Yes. But it keeps millions of people in employment, doing research, designing and building wind and tidal generators and solar panels, so the juggernaut rolls on, ignoring or sidelining any voices that question its basis. "It is difficult to get a man to understand something when his salary depends on his not understanding it" Upton Sinclair

. Hear, hear!

It says more than that. It says clouds are responsible for negative feedback, which mainstream AGW hypothesisers don't accept. It's one of the several reasons why climate temperature models predicting 'fireball earth' (I exaggerate) are getting it so wrong and are way above reality.

[The Natural Philosopher]

I think its total bollocks. A modest increase in CO2 would benefit greening the planet, and some of its more arid areas.

And historically a slightly warmer planet has seen humanity flourish