Easy⏱ time30 min$ cost2

Rain Gauge

Build and calibrate a gauge to measure rainfall and track it over weeks.

Result first

The build

Step 01

Funnel into a straight jar.

Step 02

Tape a ruler scale to the side.

Step 03

Set it in the open, away from cover.

Step 04

Log depth after each rain.

Working Principle

Rain falls evenly, so the depth collected in a straight-sided container equals the rainfall depth over any area.

The science behind it

A constant cross-section means collected volume scales directly with depth, giving a true rainfall reading.

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