A new space‑based instrument to study how effectively plants use water is being developed at NASA's Jet Propulsion Laboratory. The ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) will monitor one of the most basic processes in living plants: the loss of water through the tiny pores in leaves, or transpiration. ECOSTRESS will measure combined evaporation and transpiration, known as evapotranspiration, from the International Space Station.

NASA's ECOSTRESS will monitor how plants react to heat and water stress. (Wikimedia Commons)

ECOSTRESS's science instrument is a high‑resolution thermal infrared radiometer that works like a giant thermometer from space to measure the temperature of plants and the amount of heat radiating from Earth's surface. ECOSTRESS will provide a four‑day repeat cycle and a spatial resolution of 125 feet by 185 feet, high enough to see most farms and small differences within ecosystems.

By combining the instrument's measurements with other ecosystem data, scientists will be able to calculate how efficiently plants use water to process carbon dioxide, and identify plants likely to be more resilient during droughts.