Man Made Climate Change - Evidence Based Discussion

[stewfox]

Interesting in terms of modeling

 

http://tallbloke.wordpress.com/2014/08/27/extending-a-new-lunar-thermal-model-part-ii-modelling-an-airless-earth/

[Geoffwood]

Interitus. The rant about nocturnal ice making was about quantifying in understandable terms the lack of radiative losses from the surface with the current atmosphere. Surface radiative emissions are not slightly lowered but massively depleted. I'll write a longer reply later. Short of time now, but I will come back to this.

[knocker]

Hi knocker.

Your attached thumbnail shows that solar radiation is more intense than that of the Earth. The Earth emitting less though from more places.

The two fluxes are not directly comparable. The flux from the sun is near parallel, whereas the Earth's surface emits through 2pi steradians.

The solar flux can therefore continuously exploit the short atmospheric paths continually shown to the Sun as the Earth rotates. Some 80% of the energy entering the Earth system does so within 40deg latitude of the seasonal equator.

However, for all points on the surface many solid angles of emission encounter long atmospheric paths and therefore greater optical 'thickness' and attenuation. Only a those solid angles around the zenith can exploit short paths. This effect is independent of atmospheric composition and is a function of geometry.

Atmospheric opacity can be quantified for incoming radiation from Trenberth's (that ok?) energy balance. The atmospheric opacity for incoming radiation is 0.46 or 46% leaving 0.54 transmitted to the surface.

Of the netted, or real energy that we can express in Wm-2 as part of the surface energy budget, again from Trenberth's energy diagram 63Wm-2 leaves the surface and 40Wm-2 passes through the atmospheric window. Showing a long wave transmittance for the atmosphere of 0.63. So according to Trenberth's diagram the atmosphere attenuates a greater portion of incoming radiation compared to outgoing radiation.

This diagram may help.

The Sun emits at around 0.6um with over 50% of the band radiance at longer wavelengths than 0.7um (IR and beyond). The Earth's peak emission is centred around 10um for 300K.

 Hi Geoffwood

 

From Earth’s Annual Global Mean Energy Budget

 

J. T. Kiehl and Kevin E. Trenberth

National Center for Atmospheric Research,* Boulder, Colorado

 

The earth’s annual global mean energy budget based on the present study. Units are W m-2.

Edited September 27, 2014 by knocker

[knocker]

 Hi Geoffwood

 

From Earth’s Annual Global Mean Energy Budget

 

J. T. Kiehl and Kevin E. Trenberth

National Center for Atmospheric Research,* Boulder, Colorado

 

The earth’s annual global mean energy budget based on the present study. Units are W m-2.

 

This has actually been updated in;

 

EARTH’S GLOBAL ENERGY BUDGET

 

by Kevin E. Trenberth, John T. Fasullo, and Jeff rey Kiehl

 

 

An update of the Earth’s global annual mean energy budget is given in the light of new observations and analyses. Changes over time and contributions

from the land and ocean domains are also detailed.

[Devonian]

https://forum.netweather.tv/topic/80838-sceptical-about-climate-change-reasons-and-opinion/page-8#entry3046353

 

Stew the words you object to were being used as an analogy...Just, indeed, like one might the words Stalin and gulag?

[jonboy]

https://forum.netweather.tv/topic/80838-sceptical-about-climate-change-reasons-and-opinion/page-8#entry3046353

 

Stew the words you object to were being used as an analogy...Just, indeed, like one might the words Stalin and gulag?[/quote

Perhaps Dev there is a time to but out and this is one off them!!!

[knocker]

Steve Easterbrook has a series of articles on his blog that looks interesting considering some recent posts.

 

The Climate as a System, part 1: the central equilibrium loop

http://www.easterbrook.ca/steve/2013/08/the-climate-as-a-system-part-1-the-central-equilibrium-loop/

Edited September 28, 2014 by knocker

[Devonian]

https://forum.netweather.tv/topic/80838-sceptical-about-climate-change-reasons-and-opinion/page-8#entry3046353

 

Stew the words you object to were being used as an analogy...Just, indeed, like one might the words Stalin and gulag?[/quote

Perhaps Dev there is a time to but out and this is one off them!!!

 

I was talking to Stew...

Edited September 28, 2014 by Devonian

[Polar Maritime]

Can we please keep discussion friendly with-out the back stabs/digs and jibes, The subject is complicated enough... A little respect for one another would go a long way.

[stewfox]

I was talking to Stew...

 

Sorry I didn't have a  clue what you meant so lets move on.

[Devonian]

Deleted.

 

Wrong thread...

Edited September 28, 2014 by Devonian

[Interitus]

Interitus. You say,

"Forget obfuscation with physics, it is so very, very simple and this is the universal way it is calculated."

But it doesn't represent the surface!

The effective black body temperature describes as a single number how the system effectively behaves. The Earth's effective black body temperature is 255K. It in no way means that this is or should be associated directly with the surface. The main component of the Earth system that answers to space is the atmosphere producing 83% of Earth's emissions. As an average in quantity and spatial expanse it describes a mean height above the surface from which the effective assembly of radiators appears. We find 255K in the mid troposphere at a mean altitude of ~5km.

An 'average' in intensity and space makes no assertions about the maximum number in the averaged range nor the extreme of its extent. The surface being the highest temperature at the lowest extent of the radiating range. It represents an average in both.

 

You're still including atmospheric emittance - in the calculation the atmosphere is considered to be transparent to IR so all emittance is from the surface, thus the temperature does represent the surface.

 

Interesting in terms of modeling

 

http://tallbloke.wordpress.com/2014/08/27/extending-a-new-lunar-thermal-model-part-ii-modelling-an-airless-earth/

 

Good link Stew with a very in depth discussion in the comments - though slightly bewildering at times to see those such as a physics professor being challenged and ridiculed by some who clearly do not have a clue.

[knocker]

 

 

 

Good link Stew with a very in depth discussion in the comments - though slightly bewildering at times to see those such as a physics professor being challenged and ridiculed by some who clearly do not have a clue.

 

I agree on both counts and I'm not about to join them but I'm slightly puzzled by this.

 

An Albedo of 0.3 is not realistic for either regolith or ice.

 

My understanding is that the 0.3 is derived from a number of global surfaces such as forests, deserts, water,etc,  Anyway to move on another very good paper on the subject although it takes a bit of reading.

 

http://www.grida.no/climate/ipcc_tar/wg1/pdf/TAR-06.pdf

Edited September 29, 2014 by knocker

[Geoffwood]

Interitus, first we have the most basic approximation for the Earth whereby we assume it is a black body. Secondly we incorporate its albedo but still assume it radiates as a black body. Then perversely we attribute this function to the surface even though we know most of the emissions come from the atmosphere! As adopted and as you want me to accept.

With a physical model as we add detail we add realism. Authenticity is the result of addition of physical detail.

In reality gases are 'way from' black bodies and as a result have much lower emissivities.

Deny the following;

1)at equilibrium an object will emit in the long wave the equivalent of the shortwave thermalised.

2) the portion of the object that answers to space is the last broadband optical depth.

Uranus has come into equilibrium with the solar flux. It's troposphere includes the final optical depth that answers to space as a physical necessity.

Go on, tell me that it describes a surface temperature!!!!

On a planet that doesn't have one.

You and yours are making massive assumptions that by leaving out the 'physics details' you can get away with illogical assumptions.

As we add detail we inevitably arrive at the surface temperature as a basic physical consequence.

Not a 33 deg anomaly.

[Geoffwood]

This is how the goal posts are changing your going to have to run to keep up!

Wikipedia, 'greenhouse effect'

"The absorbed energy warms the surface. Simple presentations of the greenhouse effect, such as the idealized greenhouse model, show this heat being lost as thermal radiation. The reality is more complex: the atmosphere near the surface is largely opaque to thermal radiation (with important exceptions for "window" bands), and most heat loss from the surface is by sensible heat and latent heat transport. Radiative energy losses become increasingly important higher in the atmosphere largely because of the decreasing concentration of water vapor, an important greenhouse gas. It is more realistic to think of the greenhouse effect as applying to a "surface" in the mid-troposphere, which is effectively coupled to the surface by a lapse rate.

Edited September 29, 2014 by Geoffwood

[Geoffwood]

. It is more realistic to think of the greenhouse effect as applying to a "surface" in the mid-troposphere, which is effectively coupled to the surface by a lapse rate.

[Geoffwood]

Er, except the full troposphere is coupled by the mechanical lapse up to the point where we can neglect radiation!

[Geoffwood]

Hi knocker, great now we are buddies!

Have a look at this;

Edited September 29, 2014 by Geoffwood

[Geoffwood]

This shows that there is no physical mechanism to absorb radiation between 8um and 13um due to the transmission window. Therefore the atmosphere cannot emit between 8um and 13um. Therefore 390Wm-2 cannot go up and be absorbed. Rethink required!

Edited September 29, 2014 by Geoffwood

[Geoffwood]

Or do you prefer this one;

Edited September 29, 2014 by Geoffwood

[Geoffwood]

See with integration of the Planck continuum you basically 'colour in' under the line. If it isn't filled it ain't a black body, oops, looks like the sky isn't! Well according to downwelling radiation and the atmospheric window it isn't.

Gee must be down to geometry then.

Edited September 29, 2014 by Geoffwood

[Geoffwood]

Awful lot of that upwelling radiation going up and not coming back down knocker.

What do you have to say about the long wave transmission?

[Geoffwood]

It is very interesting though that it is called a 'greenhouse gas' theory when Wien displacement places outgoing surface radiation smack bang in the middle of the outgoing transmission window. What's more increase of temperature moves the outgoing peak away from CO2's fixed band absorption. Still,as said radiation at low thermal gradients to a first approximation, can be ignored.

[Geoffwood]

Even the Wikipedia article is turning against you

"Simple presentations of the greenhouse effect, such as the idealized greenhouse model, show this heat being lost as thermal radiation. The reality is more complex:"

Oops!

[Methuselah]

Even the Wikipedia article is turning against you

"Simple presentations of the greenhouse effect, such as the idealized greenhouse model, show this heat being lost as thermal radiation. The reality is more complex:"

Oops!

We all know it's complex, GW...Are you ever going to present any evidence for your guesses? Manipulating equations, one at a time (in such a complex situation) is nowt more than very simple obfuscation...