Remote sensing of evapotranspiration for water management in Brazil

 

Our goal

Provide consistent and timely access to satellite-based estimates of evapotranspiration for improved water management at multiple scales across Brazil on an open and user-friendly platform named ET Brasil .

 

Our motivation

Evapotranspiration, a measure of the water entering the atmosphere as water vapor through evaporation from the land surface and transpiration from plants, is a key driver in Earth’s water, carbon, and energy cycles.

With increasing forest fires, land cover changes from deforestation, and expanding agriculture in the tropics, using novel remote sensing technologies to monitor evapotranspiration is crucial for assessing changes in the water cycle and associated effects on interactions between the land surface and atmosphere.

Evapotranspiration data  is also an essential information for water resources management and can support decision-makers in efforts to improve water security and better allocate of water use in agricultural lands.

 

Our project

New technologies and high-performance computing have enabled significant improvements in remote sensing data and models. Using the Google Earth Engine cloud-computing platform, our research group is able to generate evapotranspiration estimates at multiple scales down to the field-level, using several models and data sources, including Landsat and MODIS images.

We also use ground-measured data across Brazil for model validation and accuracy assessment, allowing us to apply widely used global models to tropical and subtropical climates.

Before public release, our evapotranspiration estimates are submitted to peer-reviewed and high-impact journals, giving scientific credibility and reliability to the datasets.

User-friendly Earth Engine application (geeSEBAL) 

geeSEBAL can be accessed at  https://etbrasil.org/geesebal (not public released yet)

 

Research applications and case studies

Using Landsat images from 1984 to present, we’re focusing on several applications in Brazil, including assessing the impacts of deforestation in the Amazon on surface-atmosphere water fluxes and water use associated with expanding acreage of irrigated cropland.

Assessing impacts of deforestation on surface-atmosphere interaction in the Amazon’s “Arc of Deforestation”

 

Mapping cropland expansion and agricultural water use in Brazil

 

Areas of ongoing research

  • Assessment of large-scale drivers of evapotranspiration in South America
  • Data fusion to estimate seasonal evapotranspiration at high spatial and temporal resolutions
  • Impacts of deforestation on surface-atmosphere interaction in the tropics
  • Irrigated cropland expansion mapping and agricultural water use
  • Multi-model ensemble intercomparison based on surface energy balance and vegetation-based algorithms
  • Multi-model calibration and validation for tropical applications
  • Regional applications of global algorithms

 

Our research team and partners

Our team is part of the Large-Scale Hydrology (HGE) research group, hosted at the Institute of Hydraulic Research (IPH), from the Federal University of Rio Grande do Sul (UFRGS), Brazil. The project includes researchers with specialties in hydrology, remote sensing and water resources engineering.

Development of ET Brasil is supported by the Brazilian Water Agency (ANA), the National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (CAPES), with in-kind support from the Google Earth Engine team and many other national and international institutions.

The HGE team:

To access our up-to-date list of publications, please navigate to https://www.researchgate.net/profile/Anderson-Ruhoff/research

Our main funding agencies include the Brazilian Water Agency (ANA), the National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (CAPES), with in-kind support from the Google Earth Engine team and many other national and international institutions.

Our Brazilian research partners include:

  • Brazilian Water Agency (ANA)
  • University of Sao Paulo (USP)
  • National Institute for Space Research (INPE)
  • Federal University of Santa Maria (UFSM)
  • Federal University of Mato Grosso (UFMF)
  • Federal University of Campina Grande (UFCG)

Our South American partners include:

  • Universidad Nacional del Litoral (Argentina)
  • Instituto de Ciencias de la Naturaleza, Territorio y Energías Renovables (Peru)
  • Research Institute of the Peruvian Amazon (Peru)

For more information about the ET Brasil research group, please contact Anderson Ruhoff at andersonruhoff (at) gmail.com.