ATP Questions: Does Earth heated more by UV or infrared?

[Dasein]

Hi there. I am working on my ATPL preparation. In my aerocorse material, the book is suggesting the Earth is heated by shortwave (UV) radiation, while I have a strong impression that infrared is the major heating factor, since water is more sensitive to IR radiation.

Can anyone confirm and explain the correct answer a bit more please?

[CruiserNU]

The Earth is heated by UV rays. Once heated, the Earth gives off infrared radiation.

[photofly]

In terms of radiant energy, the sun doesn't output very much UV, at least not compared to the ferocious amounts of energy in the visible and near-infrared wavelengths:
https://www.researchgate.net/profile/Yo ... he-top.png

The earth's atmosphere is transparent to near infra-red from the sun (5700K), which heats the earth, and opaque to the far infra-red that the earth emits (at around 300K).

So I would say Aerocourse has it wrong.

[‘Bob’]

I’m curious as to why this is a question.

I’m more curious as to why they would suggest UV is the strongest contributor to heating the earth when a good part of the reason for the existence of the stratosphere and the steady -56.5C temperature from 36,000ft to 65,000
ft.. and then increasing as you go higher in ISA is because of the heat released due to the absorption of UV by the ozone layer.

[co-joe]

I think the point of the question is to understand that the sun doesn't heat the air, it heats the earth, which in turn heats the air. Definitely an FSQ.

[Bede]

The Earth is heated by UV rays. Once heated, the Earth gives off infrared radiation.

Fluorescence is cool.

[photofly]

I think the point of the question is to understand that the sun doesn't heat the air, it heats the earth, which in turn heats the air. Definitely an FSQ.

Except that UV is absorbed in the upper atmosphere by ozone, raising the temperature of the stratosphere. Is that fair?

I think the question isn't very clear. When it talks about heating the Earth, does it mean Earth as in the solid ground, or the Earth as in the planet including all its atmosphere?

[tsgarp]

Visible light has a shorter wavelength than IR, but longer than UV, so it penetrates to the Earth’s surface where it is absorbed, heating the surface which heats the troposphere. High energy UV strikes oxygen in the upper atmosphere which produces ozone, the ozone absorbs a broader spectrum of UV which in turn heats the ozone.

[tsgarp]

The Earth is heated by UV rays. Once heated, the Earth gives off infrared radiation.

Fluorescence is cool.

I miss phosphate detergents….

[co-joe]

I think the point of the question is to understand that the sun doesn't heat the air, it heats the earth, which in turn heats the air. Definitely an FSQ.

Except that UV is absorbed in the upper atmosphere by ozone, raising the temperature of the stratosphere. Is that fair?

I think the question isn't very clear. When it talks about heating the Earth, does it mean Earth as in the solid ground, or the Earth as in the planet including all its atmosphere?

Exactly why I said it's an FSQ. A Fn Stupid Question

[lownslow]

Somewhere a TC employee is jacking off furiously over this question and how someone could start by trying to make a valid assessment of a candidate’s knowledge but then get lost so far up their own ass in the pedantry of it all.

In conclusion, I have never needed to know what portion of the EM spectrum is responsible for making a thunderstorm.

[Inverted2]

I thought global warming, er “climate change” heats the earth. Yes I’m looking at all you bad people who heat your homes and drive cars around.

[linecrew]

I thought cow farts is what heated the earth.