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So a basic computation of the total greenhouse effect using a blackbody assumption and an albedo of 0.7, that of stone and water, shows that the atmosphere i.e.

by midjji 5y ago

So a basic computation of the total greenhouse effect using a blackbody assumption and an albedo of 0.7, that of stone and water, shows that the atmosphere i.e. the greenhouse effect lifts the temperature of the earth from -70C to 4C. Details can be changed about a bit, but the size of the earth and the temperature of the sun, and their distance are pretty damned exact. Minor sources like residual heat, radiological warming and lunar gravity stirring are too small and can be ignored. So if it had been doubled it would have increased to 78 C, which is obvious bullshit.

miltondts 5y ago
Did you take into account the warming of the oceans? They have 3 orders of magnitude more mass than air (1.37 × 10^21 kg vs 5.1480×10^18 kg), and take much more energy to heat per mass.
- midjji 5y ago
  I disregarded that 99% of the earth is melted i.e. not in yet in thermal equilibrium with its surroundings. Mostly because it does not matter. This is showing how large the greenhouse effect really is, about 74 degrees. That is how much heat the earth "traps", and while its getting warmer, its getting a degree or two warmer, not slowly ramping up from 4C to 78C. My point is more one of technical correctness. People keep thinking that the greenhouse effect is something new and strange, but without it the earth would be a snowball regardless of the about 0.5% increase we have affected so far, or the predicted 1% increase we will get in 30 years at current development. When people are saying the greenhouse effect has suddenly increased temperature by 1C they make people go what, that sounds strange and huge? if you say, the sum total of human activity in the world has had an 0.5% effect on the critical 74C atmosphere greenhouse property people generally go really, not more? The bad framing caused by shitty incorrect titles like the one linked is making the problem worse. Politicians arent saying our atmospheric impact on the greenhouse effect is insignificant so far, they are outright denying that the greenhouse effect exists. And they get away with it because of bad framing.
jfengel 5y ago
Headline is ambiguous but TFA is not. That 4C temperature is the long-term equilibrium. The word "trapped" in the headline means the amount of additional energy that goes to alter that equilibrium. It's not measuring the total greenhouse effect. It's measuring the additional greenhouse effect. Or rather, all of the total factors contributing to warming, which includes things like more blue ocean rather than bright ice. As you note, the existing greenhouse effect is really quite large, and the additional ~200 ppm of carbon dioxide is relatively small. It leads to a change of about 1C so far, and perhaps a total of 3-4C over the next century. But those changes are significant when it comes to human society, both directly because of the temperature and indirectly due to an increase in extreme events.

by midjji 5y ago

miltondts 5y ago

Did you take into account the warming of the oceans? They have 3 orders of magnitude more mass than air (1.37 × 10^21 kg vs 5.1480×10^18 kg), and take much more energy to heat per mass.

midjji 5y ago
I disregarded that 99% of the earth is melted i.e. not in yet in thermal equilibrium with its surroundings. Mostly because it does not matter. This is showing how large the greenhouse effect really is, about 74 degrees. That is how much heat the earth "traps", and while its getting warmer, its getting a degree or two warmer, not slowly ramping up from 4C to 78C. My point is more one of technical correctness. People keep thinking that the greenhouse effect is something new and strange, but without it the earth would be a snowball regardless of the about 0.5% increase we have affected so far, or the predicted 1% increase we will get in 30 years at current development. When people are saying the greenhouse effect has suddenly increased temperature by 1C they make people go what, that sounds strange and huge? if you say, the sum total of human activity in the world has had an 0.5% effect on the critical 74C atmosphere greenhouse property people generally go really, not more? The bad framing caused by shitty incorrect titles like the one linked is making the problem worse. Politicians arent saying our atmospheric impact on the greenhouse effect is insignificant so far, they are outright denying that the greenhouse effect exists. And they get away with it because of bad framing.

jfengel 5y ago

Headline is ambiguous but TFA is not. That 4C temperature is the long-term equilibrium. The word "trapped" in the headline means the amount of additional energy that goes to alter that equilibrium. It's not measuring the total greenhouse effect. It's measuring the additional greenhouse effect. Or rather, all of the total factors contributing to warming, which includes things like more blue ocean rather than bright ice. As you note, the existing greenhouse effect is really quite large, and the additional ~200 ppm of carbon dioxide is relatively small. It leads to a change of about 1C so far, and perhaps a total of 3-4C over the next century. But those changes are significant when it comes to human society, both directly because of the temperature and indirectly due to an increase in extreme events.