The discussion focuses on the mechanisms of heat transfer in the atmosphere, particularly the greenhouse effect and the distribution of thermal radiation. It is established that the atmosphere emits more thermal radiation downwards (approximately 340 W/m²) than upwards (about 200 W/m²), contradicting the assumption that energy is equally distributed. The conversation highlights the roles of conduction, convection, and radiation, with radiation being the primary method of energy transfer to space. Participants emphasize the importance of understanding these processes to grasp the Earth's energy budget accurately.
PREREQUISITESClimate scientists, environmental researchers, educators in atmospheric science, and anyone interested in understanding the complexities of heat transfer and the greenhouse effect in relation to Earth's climate system.
Why do you say that? Did you carefully look at the picture?F X said:That can't possibly be correct. It would mean the planet is always heating up, and very fast.
It's not clear what you are claiming. It's impossible, just a physical impossibility for each square meter of the planet to have 342 watts per square meter being added all the time. The budget has to balance, the amount of heat in has to equal the amount out or the planet is heating up at every second in time. If you shine 342 watts of energy on a square meter surface you will learn what this actually causes to happen, and fast. Physics tells us it is impossible for that amount of energy to the added to the planet. The world would never have lasted.klimatos said:For historical reasons, heat budgets are usually given in units of watts per square meter, averaged over the Earth’s entire surface. One watt is one joule per second. Since the Earth’s surface area is exactly four times its disc area, this gives us an energy income for our global heat budget of 342 watts per square meter—more or less.
The atmosphere emits 169.9 W/m2 + 29.9 W/m2 = 199.8 W/m2 towards space, and 340.3 W/m2 towards Earth, exactly as @D H said.F X said:The IR amount shown leaving (arrows pointing away from planet) is 343.8, the amount pointing towards the planet is 340.3
So "The atmosphere as a whole emits more thermal radiation to the Earth's surface (340 than it does to space (200 W/m^2)" is completely wrong. It's comparing just two parts of the picture, not the whole amounts.
The Earth's surface is emitting 398.2 W/m2...F X said:Just think about the claim. It can't even be possible. An extra 140 W/m^2 would cook the planet in a short time. It's self evident.
F X said:The IR amount shown leaving (arrows pointing away from planet) is 343.8, the amount pointing towards the planet is 340.3
So "The atmosphere as a whole emits more thermal radiation to the Earth's surface (340 than it does to space (200 W/m^2)" is completely wrong. It's comparing just two parts of the picture, not the whole amounts.
Just think about the claim. It can't even be possible. An extra 140 W/m^2 would cook the planet in a short time. It's self evident.