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417 words used in the labs.

Find a term from the labs, understand the process behind it, and see how it appears in the landscape. Each entry connects an explanation with a real observation and a model you can explore.

Af

Köppen tropical rainforest climate: every month averages at least 18 °C and receives at least 60 mm of precipitation.

What to look for

Tropical forest at Bodiman, Cameroon. This is a landscape example for tropical rainforest climate; an Af classification is determined from long-term monthly temperature and rainfall, not from vegetation alone.

Dense green tropical forest canopy at Bodiman, Cameroon.
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Explore further with USGS water glossary · USGS volcano glossary · NPS glacial geology · NASA Earth facts. Photograph acknowledgements are collected on the Image credits page.