Science Forums 2

modest · 01-09-2009

Quote:

Originally Posted by Turtle

curious about where/how the heat from the core figures in to what is radiated from surface?

Good question!

The heat flux from the internal heat flow of the earth is approximatly 75 $erg \ cm^{-2} \ s^{-1}$ . This is given here:

Google book source

To convert 75 $erg \ cm^{-2} \ s^{-1}$ to watts per meter squared (since those were the units we were using),

$\left( \frac{75 \ erg}{s} \right) \times \left( \frac{1.0 \times 10^{-7} \ J}{1 \ erg} \right) \times \left( \frac{1 \ W}{1 J \ s^{-1}} \right) \times \left( \frac{10000 \ cm^2}{1 \ m^2} \right) = 0.075 \ W / m^2$

The contribution is then 0.075 $W/m^2$ . This is verified by this source:

Allen's Astrophysical Quantities

which gives values of .078 W/m^2 for the ocean and .0565 for land.

Thus, the heat contribution available to the lower atmosphere and upper crust from the core is approximately 0.075 W/m^2 compared to the approximately 1360 W/m^2 available from the sun. That's about .005%—it is not significant for the calculation.

I hesitate to point at this source, because the first 4 paragraphs are unhelpful and slightly wrong, but it does (at the bottom) the same calculation in the same context as above.

~modest

Science Forums 2

Hypography?

Share the love!

Sponsors

Friends