Science · Environmental Science
Chapter 1: Environmental Systems and Science
The measurement and the decision are different questions.
In 2023 and 2024 four hydroelectric dams on the Klamath River, in Oregon and California, were torn down. About 160 megawatts of generating capacity went with them, and about 400 miles of river reopened to salmon. Leo and Maya read the same fact sheet and reach opposite verdicts.
If they agree on every number, what are they disagreeing about?
Make your guess to turn the page.
Still to come: 10 pages · Lab · Words to Know · What We Learned · 4 questions · Explain It in Writing · Open Questions
The idea this lesson is working on — Students assume that an environmental disagreement means one side is ignoring the evidence. The book gives two partners identical numbers about the Klamath dams and opposite verdicts, and the lab settles an empirical question cleanly while its readout has nothing to say about whether the result is worth its cost. Ask: which part of this argument is a claim about the world, and which is a claim about priorities? The idea to reach is that science settles the first and constrains the second without deciding it.
The figures and where they come from — The Klamath figures are rounded from the removal project and news reporting: J.C. Boyle, Copco 1 and 2 and Iron Gate, about 160 MW combined, about 400 miles of habitat, removal completed in 2024, and Chinook seen above the former sites that October. The ozone hole was reported by Farman, Gardiner and Shanklin in 1985; the Montreal Protocol reached universal ratification in 2009; the 2066 date is the 2022 WMO/UNEP assessment for Antarctica.
Mechanism, never a position — The book deliberately does not say whether the dams should have come down or how climate policy should be designed. It lays out what the evidence settled, what it could not, and why the structure of a problem shapes how fast agreement comes. A student who can separate those can evaluate an argument instead of choosing a side by reflex.