The “enhanced” greenhouse effect that wasn’t

Update (March 24th) at the end of this post – a kind of response from Feldman.



There was much ado recently about a new paper published in ‘Nature’ (“Observational determination of surface radiative forcing by CO2 from 2000 to 2010″ by Feldman et al.) claiming to have observed a strengthening in CO2-specific “surface radiative forcing” at two sites in North America going from 2000 to the end of 2010 (a period of 11 years) of about 0.2 W/m2 per decade, and through this observation further claiming how they have shown empirically (allegedly for the first time outside the laboratory) how the rise in atmospheric CO2 concentration directly and positively affects the surface energy balance, by adding more and more energy to it as “back radiation” (“downwelling longwave (infrared) radiation” (DWLWIR)), thus – by implication – leading to surface warming.

In other words, Feldman et al. claim to have obtained direct empirical evidence – from the field – of a strengthening of the “greenhouse effect”, a result, it would seem, lending considerable support to the hypothesis that our industrial emissions of CO2 and other similar gaseous substances to the atmosphere has enhanced, and is indeed enhancing still, the Earth’s atmospheric rGHE, thus causing a warming global surface – the AGW proposition.

From the abstract:

(…) we present observationally based evidence of clear-sky CO2 surface radiative forcing that is directly attributable to the increase, between 2000 and 2010, of 22 parts per million atmospheric CO2.”

And,

“These results confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions, and provide empirical evidence of how rising CO2 levels (…) are affecting the surface energy balance.”

So the question is: Do these results really “confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions”?

Of course they don’t. As usual, the warmists refuse to look at the whole picture, insisting rather on staying inside the tightly confined space of their own little bubble model world. Continue reading

The greenhouse effect that wasn’t (Part 1)

This turned out to be a longer post (the first of two) than what I had originally planned. The actual presentation and analysis of data starts only about halfway through. If you don’t much care for my ranting about how ‘the climate establishment’ deliberately employ specious arguments and methods to try and make us believe and perceive that clouds somehow massively warm the Earth even when they’re not, then please feel free to scroll past the first three or four sections.


THE NEGATIVE “CLOUD GREENHOUSE EFFECT”

Yes, we have all experienced how clouds covering the sky on a sunny day will tend to cool things down. Heck, shade or sunshine, which is hotter? Likewise, I think most of us can attest to the experience of how a cloudy night will be milder than a clear one.

These two different ‘cloud effects’ work in opposite directions. During the day, the heat comes in from the Sun: Qin. If you then pull a blanket or something similar between you and the heat source, you will (hopefully) avoid being overheated. People living in deserts know all about this principle. They wear their long, loose, bright garments not to stay warm, but in order to stay cool. Note, there is also heat going out (from the surface) during the day (Qout) – a direct consequence of the original solar heat input. But in most cases, this is totally overwhelmed by the incoming solar heat, so much so that it’s normally forgotten about, unless you happen to step onto a hot pavement or sand. Since the outgoing heat is also very much dependent on the original solar heating, reducing Qin during the day would also necessarily reduce Qout.

During the night, there is no more heat coming in from the Sun. There is only the heat going out, at this point from excess solar energy having accumulated during the day. So the surface is no longer being heated. Its temperature is dropping. It loses energy (as heat). Cooling. It cools directly to space, but also substantially to the air/atmosphere above it, which then in turn cools to space from higher up on its behalf, so to say. What happens if we now pull a blanket over the scene? Well, the remaining heat source, the ground, is now obstructed from direct access to its ultimate cold reservoir, space. The heat being expelled is to a much lesser degree able to go straight to the outer, icy cold heat sink, it goes rather to the more warmish layer in between. Reducing the overall gradient, thus reducing the cooling rate. People living in cold places know all about this principle. They wear thick, heavy, fluffy clothes in multiple layers, not to stay cool, but to stay warm.

The wonders of insulation! It works both ways. You only need to figure out where the principal heat is coming from.

OK, so this should be our starting point: Clouds exert both an indirect ‘cooling’ and an indirect ‘warming’ influence on surface temperatures. They take away from the solar input during the day (>Qin), and they reduce the ground’s cooling rate during the night (>Qout).

So which of these contrary ‘cloud effects’ is stronger?

Well, the heading above should give you an inkling of sorts. But I fear we will have to wind our way forward a bit before reaching final enlightenment.

First we need to revisit an old friend. Yes, that old friend … Continue reading