It’s often said by Great Plains farmers that the next drought could be around the corner. A look at the most recent U.S. Drought Monitor Index shows exceptional levels of drought in areas already prone to dryness.
That’s why no-till practices is so important for reducing or eliminating soil disturbance and keeping adequate soil moisture around for crops.
Water can be released from the Earth through both evaporation or transpiration, the latter a measure of water loss from plants. The combination of those two events is “evapotranspiration” and being able to measure that is important to growers for tracking the productivity or stress of crops.
Accurate estimations of evapotranspiration rates can help growers react to changes and control water consumption, but those estimates aren’t easy to calculate.
There are many factors determining the evapotranspiration rates, such as land cover, vegetation type, humidity, temperature and wind speed. The Earth’s surface also reveals from space that plots and fields differ in shape or crop type and may also affect the evapotranspiration rate.
Work being done by a European company’s Earth observation program, Copernicus Land Monitoring Service, could unveil insights on how evapotranspiration can be more accurately measured and the data used to help farm management.
The company notes that parcel-specific estimates of evapotranspiration are key for sustainable agriculture and water management.
With more exact knowledge of evapotranspiration rates, farmers can easily identify crops under water stress even before they show any visible signs of damage. Evapotranspiration rates can be used for irrigation and water consumption monitoring to make sure that irrigation water is not wasted.
The global component of the Copernicus Land Monitoring Service provides a range of global products used to estimate evapotranspiration.
Land cover maps give information about different types of physical coverage of the Earth’s surface. Several products can be used to estimate vegetation type and condition, such as Normalized Difference Vegetation Index (NDVI), Leaf Area Index (LAI), or Fraction of Absorbed Photosynthetically Active Radiation (FAPAR). They also provide information about Land Surface Temperature (LST), which is estimated from top-of-atmosphere brightness temperatures together with albedo, vegetation cover and soil moisture.
The company says evapotranspiration and LST monitoring will become even easier in the future as it works to add high spatial-temporal resolution thermal infrared (TIR) observations to current Sentinel observation capabilities in support of agricultural management.
If your crops are under heat and water stress, have you found that by the time you discovered it, yield potential has already been lost?
Advanced tools such as these are going to be very important in the future for growers in semi-arid regions to both keep their farms productive and profitable but also safeguard precious water supplies for future generations. If you aren’t utilizing some of this new technology somehow, maybe it’s time.