Your location: Home

Compendium on methods and tools to evaluate impacts of, and vulnerability and adaptation to, climate change


AquaCrop, a new version of CROPWAT, is a Windows-based software programme designed to simulate biomass and yield responses of field crops to various degrees of water availability. Its application encompasses rain fed as well as supplementary, deficit and full irrigation. It is based on a water-driven growth-engine that uses biomass water productivity (or biomass water use efficiency) as key growth parameter (WPb).

The model runs on daily time-steps using either calendar time or thermal time. It accounts for three levels of water-stress responses (canopy expansion rate, stomatal closure and senescence acceleration), for salinity build-up in the root zone and for fertility status.

AquaCrop is a tool for:

  1. Predicting crop production under different water-management conditions (including rain fed and supplementary, deficit and full irrigation) under present and future climate change conditions;
  2. Investigating different management strategies, under present and future climate change conditions.
Appropriate Use

AquaCrop is useful for cropping planning and management and is mainly intended for practitioners such as those working for extension services, governmental agencies, NGOs and various kinds of farmers’ associations. It is useful for developing irrigation strategies under water deficit conditions.

AquaCrop is particularly useful for perspective studies as it includes biomass and yield predictions under global warming and elevated CO2, i.e., it is suitable for climate change types of studies.

Scope AquaCrop can be applied to any field condition worldwide (once calibrated, it can be extrapolated in space and time). The “field-plot” scale should be the most appropriate spatial scale, while the “day” time-step is the time scale.
Key Output AquaCrop is a crop-growth model predicting biomass and yield response to water under any climatic and soil conditions, including climate change cases.
Key Input AquaCrop requires weather data (air temperature, reference evapotranspiration and rainfall), soil texture data (sand, clay, loam, in %) and crop parameters (initial, final and rate of change in % Canopy Cover; initial, final and rate of deepening in root depth; biomass water productivity; harvest index; typical management conditions such as irrigation dates and amounts, sowing and harvest dates, mulching, etc.).
Ease of Use AquaCrop is user-friendly. The degree of difficulty can be rated very low.
Training Required AquaCrop comes with documentation and people do not require training to use it. Nevertheless, it is generally recommended to participate in periodic training workshops that are offered for special applications.
Training Available Training sessions are periodically organized based on demand.
Computer Requirements AquaCrop runs on PCs with Microsoft Windows operating systems and requires 5 Mb of Hard Disk space.
Documentation AquaCrop includes a “User’s Guide” and “Technical Manual” for the calculation procedures and algorithms.

AquaCrop is at prototype level. Applications, tests and validations are under publication (first official document will be available in 2008).

Contacts for Framework, Documentation, Technical Assistance

Pasquale Steduto

Chief of Water Unit, Land and Water Division, Food and Agricultural Organization of the United Nations (FAO), Viale delle Terme di Caracalla, 00153 Rome, Italy; e-mail:

Cost AquaCrop will be downloadable from the Internet. It is intended to be free of charge. The hard-copies of the documentation and the CD with the software will be inexpensive (to cover the hardcopy production cost).

AquaCrop is new and has not yet developed publications that have critically discussed its use.