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Liquid water and precipitation rate

Water forms one of the most important constituents of the Earth’s atmosphere and is essential for human existence. The global water cycle is at the heart of the Earth’s climate system, and better predictions of its behaviour are needed for monitoring climate variability and change, weather forecasting and sustainable development of the world’s water resources.
Detailed MeasurementDescription*InstrumentsTimeline
Precipitation index (daily cumulative)Cumulative precipitation over a 24-hour period.3 instruments
Precipitation intensity at the surface (liquid or solid)
Intensity of precipitation reaching the ground - Physical unit: [ mm/h ] (if solid, mm/h of liquid water after melting) - Accuracy unit: [ mm/h ]. Since accuracy changes with intensity, it is necessary to specify a reference intensity. Assumed rate: 5 mm/h.33 instruments
* Description adapted from WMO.