NASA will monitor plants’ water usage through new instrument on ISS
The ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) will track the health of plants worldwide and provide information that will help scientists predict droughts and address them in their early stages.
Increases in plant’s temperature indicates can mean it is becoming dehydrated. When heated by sunlight, plants transport water their roots absorbed from the soil to pores in their leaves, from which it is released. Known as transpiration, this process cools plants much like sweating cools humans.
When a plant does not get enough water, it conserves what it has by closing these pores, which increases its temperature. Continued lack of water causes plants to go into a condition known as “water stress.”
Plants produce their own food, which involves transforming carbon dioxide and water into sugar through a process known as photosynthesis.
Because they absorb atmospheric carbon dioxide from the same pores in their leaves through which water is released, closure of these pores can cause them to starve, overheat, and eventually die.
“When a plant is so stressed that it turns brown, it’s often too late for it to recover,” noted ECOSTRESS principal investigator Simon Hook of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “But measuring the temperature of the plant lets you see that a plant is stressed before it reaches that point.”
By regularly monitoring the temperatures of plants around the globe, ECOSTRESS will enable scientists to address agricultural water imbalances while plants can still be saved.
If many plants in a particular area show signs of water stress, ECOSTRESS data will function as an early warning of potential drought in that area.
“ECOSTRESS will allow us to monitor rapid changes in crop stress at the field level, enabling earlier and more accurate estimates of how yields will be impacted. Even short-term moisture stress, if it occurs during a critical stage of crop growth, can significantly impact productivity,” said ECOSTRESS science team member Martha Anderson of the US Department of Agriculture (USDA) in Beltsville, Maryland.
From low-Earth orbit on the ISS exterior, ECOSTRESS will take plant data from multiple regions at various times of day. Every three to five days, it will produce detailed images of regions as small as 43 by 76 yards (40 by 70 meters).
Unlike other instruments studying the Earth, ECOSTRESS can conduct measurements at the same level of detail at different types of day, a capability that will prove useful for scientists in terms of water and food resource management.
“As water resources become more critical for our growing population, we need to track precisely how much water our crops need,” stated ECOSTRESS science lead Josh Fisher of JPL. “We need to know when plants are becoming susceptible to droughts, and we need to know which parts of the ecosystem are most vulnerable because of water stress.”
Data returned by ECOSTRESS will also prove useful to scientists conducting other studies that rely on temperature information, including some seeking to detect heat waves, wildfires, and even volcanoes.
Scheduled for launch from Cape Canaveral Air Force Station on June 29 as part of a SpaceX resupply mission, ECOSTRESS will be installed robotically on the outside of the ISS Japanese Experiment Module Exposed Facility Unit. Current plans call for it to collect data for a year.
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.