Energy and Human Ambitions on a Finite Planet, 2021a

C Selected Answers 387
Chapter 9
1. A single integer works okay for all three
2. Nearly 100 kg
3. Between 10–15 kg
4. Approaching 1 GJ, <strong>and</strong> human-mass scale
5. Total is like small adult or large child
6. More than a factor of two
7. Get about 50 years; rate not constant
8. The numbers basically match
9. Between 1–2 ppm v , in agreement with Figure
9.3
10. What is it we know?
11. Seems deserving of high marks
12. Historical vs. current activity levels
13. About 10 ◦ C cooler than actual
14. Two pure cases <strong>and</strong> one partial
15. Several degrees warmer
16. Very good for us at the right level
17. Numbers are not far from realistic
18. Triple pre-industrial <strong>and</strong> almost 5 ◦ C
19. End ∼3 ◦ C high; almost linear, but not
quite
20. No need to balance: Nature doesn’t
bother
21. It’s no game-changer
29. Sum to about 700 years; almost all in ice
<strong>and</strong> ocean
30. A few hundred meters
31. A finger’s breadth per year
32. Keen to hear your thoughts
33. Keen to hear your thoughts
Chapter 10
1. Mostly clean; not all, though
2. Nothing is free
3. What would unlimited mean?
4. Table 10.2 has some help
5. Can’t rely on any sun-driven energy
6. Between 200–250 W/m 2
7. Photosynthesis supports essentially all
life
8. Comparing numbers in TW
9. More than half
10. A little less than 1%
11. Not far from 1,000 W/m 2
12. Nearly 10 degrees
13. Look for crazy-big input
14. Between 0.5–1 gallon
15. More than 4,000×
22. Student’s choice
23. E.g., 390 − 152 238 for a match
24. Use 290.6 K; looks like continuation of
panel progression
25. A few millimeters
26. A little over a century
27. A year or two
28. A couple of degrees
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