dave burton

daveburton | December 14, 2021

angech, it is specifically where the in going and outgoing energy fluxes are equal.
You know that.

Actually, I don’t know that, angech. That definition is new to me.
There is not necessarily any altitude at which the incoming and outgoing radiant energy fluxes to and from a particular location on the Earth’s are equal at any given time. On the night side, at most latitudes, outgoing flux is much greater than incoming (which is why temperatures cool after sunset). Conversely, on the day side, the outgoing flux is generally much less than the incoming flux.

Those are good points.
I think we should talk more about the definition of TOA to clear it up as others are definitely not understanding it

The problem is that TOA is actually a specific average flux figure for the whole of the planet,so the value does not vary depending on which side of the planet or which pole you are at.
Are you happy with that?

The TOA does vary in average height over the world depending firstly on the input radiation.
If the sun goes up a notch the TOA goes up a notch both in value and height.
Agreed on that?

I would guess that if albedo goes up so there is less incoming radiation that TOA value and average height go down.

Three out of three?

Now the tricky bit .
While the average height of the TOA is a specific figure the amount of energy going out increases as the amount of energy coming in increases during the day due to the sun being overhead.
The amount of energy hence the height of the TOA under the sun is quite large in value and quite high in altitude.
But it is in balance as it is measured where the two are in balance always
The TOA refers to the height of the atmosphere where the air is thin enough to allow as much energy out as came in.

Now the night side. though you do not see it, there is no heat source external to the atmosphere. The atmosphere still contains energy that is escaping to space all night long.
As long as the amount of energy going out

Nor are even the average fluxes necessarily balanced. Some places have positive average net radiative fluxes, and others have negative average net radiative fluxes, because air and water currents also transport heat.

Overall, the Earth is believed to have a current slight net energy imbalance at TOA (which NASA estimates at 0.6 W/m², but that’s pretty clearly too high).
No it is specifically where the in going and outgoing energy fluxes are equal.
You know that.
It therefor can be well within the earths atmosphere [night time cold side] but never above or outside the atmosphere.

Taken literally, it suggests some unspecified distance/displacement from the Earth’s surface or orbital path.

Not unspecified. It exists everywhere the fluxes are equal in and out all around the earth in the atmosphere.

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