NASA announced last week that both the University of Washington STRIVE team and the UW-affiliated EDGE team were selected to lead satellite missions to better understand Earth and improve capabilities to foresee environmental events and mitigate disasters.
STRIVE and EDGE were among four finalists selected in May 2024 as part of the agency's Earth System Explorers Program, which conducts principal investigator-led space science missions as recommended by the National Academies of Sciences, Engineering, and Medicine 2017 Decadal Survey for Earth Science and Applications from Space.
The total estimated cost of each mission, not including launch, will not exceed $355 million with a mission launch date of no earlier than 2030, stated NASA.
"This was fantastic news. We have been working on this concept for a few years now, and for many of us it is a dream come true. To be able to observe the atmosphere at this level of detail is a tremendous opportunity," said Lyatt Jaeglé, a UW professor of atmospheric and climate science, who is leading the STRIVE mission.
Stratosphere-Troposphere Response using Infrared Vertically-resolved light Explorer
STRIVE, which stands for Stratosphere-Troposphere Response using Infrared Vertically-resolved light Explorer, will examine the regions of the atmosphere where weather forms and the ozone layer sits, yielding new insights into temperature and trace gases in the atmosphere that affect aviation, long-range transport of volcanic smoke and air pollution.
The STRIVE instruments, compact enough to fit into the trunk of a midsize SUV, can make more than 400,000 observations each day. Instead of looking straight down at the Earth, like other missions, the STRIVE instruments angle sideways towards Earth's surface to capture the atmosphere in greater detail.
"With these observations, we won't just get measurements of ozone but rather all the chemical species that affect ozone in the stratosphere," Jaeglé said.
The ozone layer, which absorbs ultraviolet radiation, is bouncing back after severe depletion in the early 2000s, but still requires careful monitoring.
STRIVE represents a technological and scientific quantum leap that will help researchers understand how air pollution circulates following a wildfire or volcanic eruption, for example. Importantly, STRIVE will also aid weather forecasting efforts beyond the typical 10-day window to give people time to prepare for extreme weather events.
"If we can see something propagating from high up - such as large shifts in winds - then we will know that several weeks later it will impact Earth's surface. Our current weather models cannot predict this connection very well because we don't really know what is going on at the interface of the stratosphere and troposphere," Jaeglé added.
The national-scale team includes partners from academia, industry and federal science labs. Jun Wang at the University of Iowa is the deputy principal investigator of STRIVE, and Luke Oman at NASA's Goddard Space Flight Center is the project scientist. Several NASA Goddard scientists are also involved. Other UW members of STRIVE are professor Qiang Fu, assistant professor Alex Turner and affiliate faculty member Daehyun Kim, all in the UW Department of Atmospheric and Climate Science.
The Earth Dynamics Geodetic Explorer
EDGE, or Earth Dynamics Geodetic Explorer, uses lasers to observe the three dimensional structure of Earth's surface - including forests, glaciers, ice sheets and sea ice - as it changes. Benjamin Smith, a senior principal physicist and Tyler Sutterly, a senior research scientist both at the UW Applied Physics Laboratory and David Shean, a UW associate professor of civil and environmental engineering, are part of the EDGE team, led by Helen Amanda Fricker from Scripps Institution of Oceanography at the University of California San Diego.
EDGE will be the first global satellite imaging laser altimeter system, according to a press release from UCSD. The system captures surface detail in high resolution by firing laser pulses at the Earth and recording how long it takes for them to return, making over 150,000 measurements each second. It can also precisely track changes in surface elevation over time to capture how ice sheets and glaciers are responding to climate change over seasonal and longer-term timescales.
"What's really exciting about EDGE is the level of detail it will measure. Older laser altimetry measurements sample a coarse grid of points on the ground, but with the EDGE data we will be able to see individual trees around Seattle, and small cracks in glaciers in Greenland and Antarctica. Often, it's the fine-scale processes that drive how the large-scale system changes," Smith said.
Although the effort will focus on polar regions, forests and coastlines, EDGE is an "everything mission," Shean said.
"These precise surface elevation change measurements are essential for so many pressing scientific and engineering applications," he added. "The EDGE data will have implications for sea level rise, natural hazards monitoring, water resource and forest management, and wildfire response. This is also a major milestone for UW, as it formalizes UW leadership and involvement on not one, but two NASA Earth Observation missions. I'm excited to bring students onto the EDGE team and train the next generation of UW researchers who will do amazing things with EDGE data in the coming decades."
