03-20-23, 12:20 PM
From HERE
The surface of the Earth was radiating at 386 W/m2 in the year 1700 (before any increase in GHGs started) which produced an average temperature of 14.3C.
Today, the surface is radiating at 390 W/m2 which produces an average temperature of 15.0C (20C at the height of the day and 10C at the low point at sunrise and +0.7C higher than 1700).
Okay, so CO2 doubles from the year 1700 level or an extra 3.7 W/m2. The other GHGs such as Methane, N20 and the CFCs add another 0.22 W/m2 so we are at +3.92 W/m2.
From this extra +3.92 W/m2, tTemperatures increase by 1.04C at the tropopause and just 0.74C at the surface (which might imply, the lapse rate also falls from the current 6.5C/km to 6.4C/km which is close to what the IPCC estimates for the lapse rate feedback so that counts in feedback No. 1).
So what about the other feedbacks.
Water Vapour seems to increase by about 4.0% per 1.0C temperature increase (which is a little less than the climate models have and is indicated in the Classius Clapeyron equations at 7.0% per 1.0C but this is the consistent empirical estimate from all sources).
4.0% * 113.2 W/m2 * 0.5 (log impact) = +2.25 W/m2 for water vapour from this 0.74C to 1.04C temperature increase [which is very close to what the climate models have].
What about clouds? Clouds go up by about 3.0% (a little less than the water vapour increase).
Cloud long-wave positive forcing = 32 W/m2 * 3% * 0.5 (log impact) = +0.5 W/m2.
Cloud short-wave reflectance = -53 W/m2 * 3% * 1 (no log impact here now) = -1.6 W/m2.
Lets now add-in the IPCC Albedo feedback of +0.26 W/m2.
We then have —> 386 W/m2 + 3.92 W/m2 + 2.25 W/m2 + 0.5 W/m2 – 1.6 W/m2 + 0.26 W/m2 = 391.3 W/m2
—-> 15.3C or just 1.0C above the year 1700 level with just 0.3C more to go.
There you go, another estimate. All the forcings included (except for the Aerosols and solar changes which could net to Zero or a small negative if you believe Hansen which would just further reduce the numbers)
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EDITED to create Paragraphs.
The surface of the Earth was radiating at 386 W/m2 in the year 1700 (before any increase in GHGs started) which produced an average temperature of 14.3C.
Today, the surface is radiating at 390 W/m2 which produces an average temperature of 15.0C (20C at the height of the day and 10C at the low point at sunrise and +0.7C higher than 1700).
Okay, so CO2 doubles from the year 1700 level or an extra 3.7 W/m2. The other GHGs such as Methane, N20 and the CFCs add another 0.22 W/m2 so we are at +3.92 W/m2.
From this extra +3.92 W/m2, tTemperatures increase by 1.04C at the tropopause and just 0.74C at the surface (which might imply, the lapse rate also falls from the current 6.5C/km to 6.4C/km which is close to what the IPCC estimates for the lapse rate feedback so that counts in feedback No. 1).
So what about the other feedbacks.
Water Vapour seems to increase by about 4.0% per 1.0C temperature increase (which is a little less than the climate models have and is indicated in the Classius Clapeyron equations at 7.0% per 1.0C but this is the consistent empirical estimate from all sources).
4.0% * 113.2 W/m2 * 0.5 (log impact) = +2.25 W/m2 for water vapour from this 0.74C to 1.04C temperature increase [which is very close to what the climate models have].
What about clouds? Clouds go up by about 3.0% (a little less than the water vapour increase).
Cloud long-wave positive forcing = 32 W/m2 * 3% * 0.5 (log impact) = +0.5 W/m2.
Cloud short-wave reflectance = -53 W/m2 * 3% * 1 (no log impact here now) = -1.6 W/m2.
Lets now add-in the IPCC Albedo feedback of +0.26 W/m2.
We then have —> 386 W/m2 + 3.92 W/m2 + 2.25 W/m2 + 0.5 W/m2 – 1.6 W/m2 + 0.26 W/m2 = 391.3 W/m2
—-> 15.3C or just 1.0C above the year 1700 level with just 0.3C more to go.
There you go, another estimate. All the forcings included (except for the Aerosols and solar changes which could net to Zero or a small negative if you believe Hansen which would just further reduce the numbers)
=======
EDITED to create Paragraphs.
“A theory that is not refutable by any conceivable event is non-scientific.” – Karl Popper
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