7. Sun Aswan Alexandria 7.2 ° Circ. = 2 π r Circumference = 805 km ∙ 50 805 km Circ. = 40,250 km r = 6400 km 7.2 ° 1 50 r = Circ. 2 π = 7.2° 360° 805 km Circumference = 1 50
16. Systems A systems approach to Earth’s energy balance From: Strahler & Strahler Where and how does the energy flow in this global-scale natural system?
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27. Energy as a System But a scientist’s results are only as good as the data and the assumptions. What did Kelvin not know about? Convection in the mantle Heat from the radioactive decay of atomic nuclei