pyet
Open Source
Reference and potential evapotranspiration in Python — 20+ published methods, FAO-56 included, on pandas/xarray.
CROPWAT
DormantFAO's classic tool for crop water requirements and irrigation scheduling from climate and crop data.
by FAO
- Pricing
- Free
- License
- FAO freeware
- Commercial use
- Permitted
- Ecosystem
- Standalone
- Platform
- Windows
About CROPWAT
CROPWAT is the FAO's decision-support tool for irrigation: it computes reference evapotranspiration (FAO-56 Penman-Monteith), crop water requirements through the growing season, and irrigation schedules under different supply assumptions, using climate data from the companion CLIMWAT database or your own records.
The software itself is old Windows freeware, but the methodology is the global standard for irrigation planning, and CROPWAT remains the reference implementation officials and lenders recognise. For scripted workflows, modern packages (pyet for ET, AquaCrop-OSPy for yield response) cover the same ground programmatically.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
Alternatives to CROPWAT
Ranked by the topics, categories and workflow stages they share with CROPWAT.
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Integrated water resources planning and policy analysis framework for basin-scale supply and demand modeling.
MIKE SHE
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Browser-based rainfall frequency analysis — fit and rank 11 distributions with confidence intervals.
HEC-SSP
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Statistical hydrology from HEC: Bulletin 17C flood frequency, volume-duration and general frequency analysis.
SWAT+
Open Source
The USDA watershed model for land use, sediment and nutrients — continuous simulation at catchment scale.