Science

eLEAF is built on over 20 years of advanced research and we are still developing every day. Read more about the science behind our data.

The interaction of sunlight with the atmosphere, soil and vegetation determines the transport of energy and matter through ecosystems.

Our key business is to convert satellite observations into useful data products. These reflect the complex interaction between soil, vegetation and atmosphere. On this page we explain this ‘science behind our data’ by introducing the key physical processes and showing how they can be reconstructed by remote sensing observations.

Water and energy balance

eLEAF estimates the physical parameters of ecosystems, critical to land, water and crop management. These parameters emerge as part of the flow of energy and water through these ecosystems: the water and energy balance, displayed schematically in the image above. Our methods solve the water and energy balance based on satellite data.The transport of water illustrates these different processes:Rainfall and irrigation feed water into an ecosystem or agricultural field. This water enters the soil, where some of it subsequently evaporates, drains off to the groundwater layer or runs off to streams and rivers. Some soil water is taken up by plant and crop roots. Most of this water travels through the plant and transpires through stomata (small openings in leaves), leaving the vegetation in the atmosphere. Water that remains in the plant fuels photosynthesis: a chemical reaction powered by sunlight, that transfers water and carbon dioxide into plant biomass.

The energy balance traces the flow of energy through the different components of soil, vegetation and atmosphere. Solar radiation is partly reflected and partly absorbed by the atmposphere (resulting in an increased sensible heat), vegetation (used for e.g. evaporation through latent heat, internal transport and photosynthesis) and soil (dissipated as heat and evaporation through latent heat). All these separate components (soil, vegetation, atmosphere) exchange energy as heat, striving to reach thermal equilibrium.

 

Some key examples of energy and water balance components, estimated using eLEAF methodology:

Evapotranspiration (ET)

is the total amount of water that is evaporated from the soil and transpired from plants. In agriculture, it expresses the amount of water lost in the crop production process. Evapotranspiration can be used to determine water use efficiency, and whether crops or vegetation experience water stress.

Biomass production 

by crops is estimated from the amount of solar radiation received, combined with ambient conditions (availability of water, air temperature, humidity, soil moisture stress) that determine the efficiency of photosynthesis. 

Water use efficiency

the amount of biomass produced, given the available water, serves as a proxy for crop health.

 

Soil moisture content

estimates are a key decision parameter for e.g. irrigation planning.

These quantities are calculated by our models and algorithms, based on inputs from satellites: meteorological data (solar radiation, wind speed, air temperature, relative humidity), surface reflectiveness (albedo), and vegetation cover (NDVI). These are determined by weather satellites, and satellites detecting optical, thermal infrared and microwave radiation (radar). 

input data Illustration

The variables needed to solve the water and energy balance are observed by a suite of satellites in different orbits, and measured at different time intervals and spatial resolutions, as illustrated below. Our computational engine combines these different observations into uniform data products: reproducible, reliable and to be used in our different applications.

eLEAF provides satellite based application to various companies

eLEAF provides satellite based applications and data to optimise crop production and water management. Proven by our track record of over 20 years, it doesn’t matter whether you are managing a multinational agro-holding or developing complex water management policies, our state-of-the-art products will provide an extra dimension and support you to optimise your outputs.