Boiling point falls with altitude

Why does water boil at a lower temperature at altitude?

Water boils about 1 °C cooler for every 300 m of altitude.

Why it works

Lower pressure means less energy needed to boil. At 3,000 m water boils near 90 °C — food takes noticeably longer.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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More in Environmental

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