Talk:Earth's energy budget
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It would be interesting to have some comparison here with human energy production. Terry 05:02, 2 Oct 2004 (UTC)
- (William M. Connolley 21:32, 18 Oct 2004 (UTC)) Thats a fair point. Another that would be of interest is the contribution from stars; other planets (in particular reflected light from the moon (I think there was a paper on this a couple of years back)); and the cosmic microwave background.
Hmm, well, having just written about this I added the (direct) human contribution. In the course of which I notice a problem: the article says:
The total flux of power entering the Earth's atmosphere is estimated at 174 petawatts. This consists of:
- solar radiation (99.985%, or nearly 174 petawatts; or about 341.5 W/m²)
- This is equal to the product of the solar constant, about 1366 watts per square metre, and the area of the Earth's disc as seen from the Sun, about 1.28 × 1014 square metres. The figure of 341.5 W/m² is then the global average value.
- geothermal energy (0.013%, or about 23 terawatts; or about 0.18 W/m²)
- This is produced by stored heat and heat produced by radioactive decay leaking out of the Earth's interior.
- tidal energy (0.002%, or about 3 terawatts; or about 0.02 W/m²)
- This is produced by the interaction of the Earth's mass with the gravitational fields of other bodies such as the Moon and Sun.
- Waste heat from fossil fuel consumption is about 13 terawattts of 0.025 Wm² [1].
Note that the ratio of TW and W/m2 for tidal energy and geothermal is not the same as for my newly added human numbers, or for the solar radiation. I suspect a factor of 4 error somewhere, but where...?
- The problem was that the solar constant is specified over the area of the Earth's disc (πr2 = 1.3e14 m2), but the other figures are specified over the Earth's surface (4πr2 = 5.1e14 m2). It's fixed now. --Heron 20:31, 21 November 2005 (UTC)
[edit] Greenhouse effect
Just to say that I've added categories so that this article appears alongside climate forcing/change articles. Seemed a bit of an omission for this article. It probably needs an explicit subsection on anthropogenic alterations to the energy budget. --Plumbago 09:13, 21 November 2005 (UTC)
- Seems fair enough. I've added a little section. William M. Connolley 18:35, 21 November 2005 (UTC).
