Two new spaceborne Earth-observing instruments will
help scientists better understand how global forests and ecosystems are affected
by changes in climate and land use change. This image of the Amazon rainforest
is from a 2010 global map of the height of the world’s forests based on multiple
satellite datasets.
Image Credit:
NASA Earth Observatory
NASA has selected proposals for two new instruments that will observe changes
in global vegetation from the International Space Station. The sensors will give
scientists new ways to see how forests and ecosystems are affected by changes in
climate or land use change.
A laser-based system from the University of Maryland, College Park, will
observe the structure of forest canopy. This instrument will be completed in
2019 and will not cost more than $94 million. A high-resolution multiple
wavelength imaging spectrometer from NASA's Jet Propulsion Laboratory (JPL) in
Pasadena, California, will study the effectiveness of water use by vegetation.
This instrument will be completed in 2018 and not cost more than $30
million.
"We are excited to expand the use of the International Space Station to make
critical Earth observations that will help scientists understand the diversity
of forests and vegetation and their response to a changing climate," said John
Grunsfeld, associate administrator of NASA's Science Mission Directorate in
Washington. "These innovative Earth Venture Instruments will join a growing
suite of NASA Earth-observing sensors to be deployed to the station starting
this year."
The instruments were competitively selected from 20 proposals submitted to
NASA's Earth Venture Instrument program. Part of the Earth System Science
Pathfinder program Earth Venture investigations are small, targeted science
investigations that complement NASA's larger research missions. The National
Research Council recommended in 2007 that NASA undertake this type of regularly
solicited, quick-turnaround project. The program's first selection was awarded
in 2010.
Ralph Dubayah, of the University of Maryland, is the principal investigator
for the Global Ecosystem Dynamics Investigation (GEDI) Lidar. This project will
use a laser-based system to study a range of climates, including the observation
of the forest canopy structure over the tropics, and the tundra in high northern
latitudes. This data will help scientists better understand the changes in
natural carbon storage within the carbon cycle from both human-influenced
activities and natural climate variations.
Simon Hook of JPL is the principal investigator for the ECOsystem Spaceborne
Thermal Radiometer Experiment on Space Station (ECOSTRESS). This project will
use a high-resolution thermal infrared radiometer to measure plant
evapotranspiration, the loss of water from growing leaves and evaporation from
the soil. These data will reveal how ecosystems change with climate and provide
a critical link between the water cycle and effectiveness of plant growth, both
natural and agricultural.
The GEDI team has extensive experience in observing and modeling forest and
vegetation dynamics. Dubayah has led numerous vegetation lidar observations from
sub-orbital platforms throughout his career. The team includes partnerships with
NASA's Goddard Space Flight Center, Greenbelt, Maryland; Woods Hole Research
Center, Woods Hole, Massachusetts; the U.S. Forest Service, Ogden, Utah; and
Brown University, Providence, Rhode Island.
The ECOSTRESS team has extensive experience in development and analysis of
thermal infrared spectroscopic images of the Earth’s surface. Hook has served as
project scientist for the Advanced Spaceborne Thermal Emission Reflection
Radiometer (ASTER) instrument on NASA's Earth Observing System Terra satellite
and has been involved in numerous sub-orbital field campaigns. The team includes
partnerships with the U.S. Department of Agriculture, Beltsville, Maryland, and
Maricopa, Arizona; Princeton University, Princeton, New Jersey; and University
of Idaho, Moscow, Idaho.
The International Space Station provides several in-orbit capabilities useful
to both instruments. The space station orbit is inclined relative to the poles,
providing more observation time of forests and vegetation over temperate land
masses than possible from the polar orbits commonly used for other types of
Earth observations. The GEDI laser requires significant power resources, which
the space station can provide. Also, the relatively low altitude of the
station's orbit, about 260 miles up, benefits GEDI by ensuring a higher return
energy for laser pulses reflected from the ground.
In 2012, NASA selected the first Earth Venture Instrument investigation, the
Tropospheric Emissions: Monitoring of Pollution (TEMPO) mission. TEMPO will be
the first space-based sensor to monitor major air pollutants across North
American hourly during daytime. It will share a ride on a commercial satellite
as a hosted payload and orbit about 22,000 miles above the equator.
NASA's Langley Research Center in Hampton, Virginia, manages the Earth System
Science Pathfinder program for NASA's Science Mission Directorate. The missions
in this program provide an innovative approach to address Earth science research
with periodic windows of opportunity to accommodate new scientific
priorities.
For more information, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui
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