Set for launch in November, the Earth-observing satellite will closely monitor sea level and provide atmospheric data to support weather forecasting and climate models.
On Nov. 10, the world’s latest Earth-observing satellite will
launch from Vandenberg Air Force Base in California. As a historic
U.S.-European partnership, the Sentinel-6 Michael Freilich spacecraft will
begin a five-and-a-half-year prime mission to collect the most accurate
data yet on global sea level and how our oceans are rising in response to
climate change. The mission will also collect precise data of atmospheric
temperature and humidity that will help improve weather forecasts and climate
models.
The
spacecraft is named after Dr. Michael Freilich, the former director of NASA’s
Earth Science Division and a tireless advocate for advancing satellite
measurements of the ocean.
Sentinel-6 Michael Freilich builds on the heritage of the ESA (European
Space Agency) Copernicus Sentinel-3 mission as well as the heritage and legacy
of the U.S.-European TOPEX/Poseidon and Jason-1, 2, and 3 series of sea level
observation satellites. Launched in 2016, Jason-3 is currently providing data
initiated with the observations of TOPEX/Poseidon in 1992.
The
data from these satellites has become the gold standard for sea level
studies from space over the past 30 years. In 2025, Sentinel-6 Michael
Freilich’s twin, Sentinel-6B, is scheduled to launch and advance these
measurements for at least another half decade.
“This continuous record of observations is essential for
tracking sea level rise and understanding the factors that contribute to it,”
said Karen St. Germain, director of NASA’s Earth Science Division. “With
Sentinel-6 Michael Freilich, we ensure those measurements advance both in
number and in precision. This mission honors an exceptional scientist and
leader, and it will continue Mike’s legacy of advances in ocean studies.”
So how will Sentinel-6 Michael Freilich further our ocean
and climate knowledge? Here are five things you should know:
1. The spacecraft will
provide information that will help researchers understand how climate change is
reshaping Earth’s coastlines – and how fast this is happening.
Earth’s oceans and atmosphere are inextricably connected.
The sea absorbs more than 90% of the heat trapped by rising greenhouse gases,
which causes seawater to expand. This expansion accounts for about one-third of
modern-day sea level rise, while meltwater from glaciers and ice sheets accounts
for the rest.
The joint U.S.-European Sentinel-6 Michael Freilich is the next in a line of Earth-observing satellites that will collect the most accurate data yet on sea level and how it changes over time. With millimeter-scale precision, data from this mission will allow scientists to precisely measure sea surface height and gauge how quickly our oceans are rising. Credit: NASA-JPL/Caltech/NOAA
The rate at which the oceans are rising has accelerated over
the past two decades, and scientists expect it to speed up more in the years to
come. Sea level rise will change coastlines and increase flooding from tides
and storms. To better understand how rising seas will impact humanity,
researchers need long climate records – something Sentinel-6 Michael Freilich
will help provide.
“Sentinel-6 Michael Freilich is a milestone for sea
level measurements,” said Project Scientist Josh Willis of NASA’s Jet
Propulsion Laboratory in Southern California, which manages NASA’s
contributions to the mission. “It’s the first time we’ve been able to
develop multiple satellites that span a complete decade, recognizing that
climate change and rising seas are here to stay.”
2. The satellite will
see things that previous sea level missions couldn’t.
In monitoring global sea levels since 2001, the Jason series
of satellites have been able to track large ocean features like the Gulf Stream
and weather phenomena like El Niño and La Niña that stretch over thousands of
miles. However, measuring smaller sea level variations near coastlines, which can
affect ship navigation and commercial fishing, has been beyond their
capabilities.
Sentinel-6 Michael Freilich will collect measurements at
higher resolution. What’s more, it will include new technology in the Advanced
Microwave Radiometer (AMR-C) instrument that, along with the mission’s Poseidon-4
radar altimeter, will enable researchers to see these smaller, more complicated
ocean features, especially near the coastlines.
3. Sentinel-6 Michael
Freilich builds upon a highly successful U.S.-European partnership.
Sentinel-6 Michael Freilich is the first NASA-ESA joint
effort in an Earth science satellite mission, and it marks the first
international involvement in Copernicus, the European Union’s Earth Observation
Programme. It continues a decades-long tradition of cooperation between NASA, the
National Oceanic and Atmospheric Administration (NOAA), and European partners,
including ESA, the intergovernmental European Organisation for the Exploitation
of Meteorological Satellites (EUMETSAT), and France’s National Centre for Space
Studies (CNES).
These international collaborations enable access to a larger
pool of resources and scientific expertise than would be available otherwise.
Researchers have published thousands of scientific papers using the sea level
data collected by the series of U.S.-European satellite missions that began
with the 1992 launch of TOPEX/Poseidon.
4. By expanding the
global atmospheric temperature data record, the mission will help researchers better
understand how Earth’s climate is changing.
Climate change doesn’t just affect Earth’s oceans and surface;
it impacts all levels of the atmosphere, from the troposphere to the
stratosphere. A
science instrument on Sentinel-6 Michael Freilich uses a technique called
radio occultation to measure the physical
properties of Earth’s atmosphere.
The Global Navigation Satellite
System – Radio Occultation (GNSS-RO) instrument
tracks radio signals from navigation satellites that orbit Earth. When a satellite
dips below (or rises above) the horizon from Sentinel-6 Michael Freilich’s
perspective, its radio signal passes through the atmosphere. As it does, the
signal slows, its frequency changes, and its path bends. Called refraction,
this effect can be used by scientists to measure minute changes in atmospheric
density, temperature, and moisture content.
When researchers add this information to existing data from
similar instruments currently in space, they’ll be able to better understand how
Earth’s climate is changing over time.
“Like the long-term measurements of sea level, we also
need long-term measurements of our changing atmosphere to better understand the
full impacts of climate change,” said Chi Ao, the GNSS-RO
instrument scientist at JPL. “Radio occultation is a wonderfully precise
and accurate way to do that.”
5. Sentinel-6 Michael
Freilich will help to improve weather forecasts by providing meteorologists
information on atmospheric temperature and humidity.
The satellite’s radar altimeter will collect measurements of
sea surface conditions, including significant wave heights, and data collected by
the GNSS-RO instrument will complement existing observations of the atmosphere.
These combined measurements will give meteorologists further insights to
improve weather forecasts. Moreover, information on the temperature and
humidity of the atmosphere, as well as the temperature of the upper layer of
the ocean, will help to improve models that track the formation and evolution
of hurricanes.
More About the
Mission
The Sentinel-6/Jason-CS satellite pair is being jointly
developed by ESA, EUMETSAT, NASA, and NOAA, with funding support from the
European Commission and technical support from CNES.
NASA JPL developed three science instruments for each
Sentinel-6 satellite: the AMR-C, the GNSS-RO, and the Laser Retroreflector
Array. NASA is also contributing launch services, ground systems supporting
operation of the NASA science instruments, the science data processors for two
of these instruments, and support for the international Ocean Surface
Topography Science Team.
To learn more about NASA’s study of sea level rise, visit:
News Media Contact
Ian J. O’Neill / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-2649 / 818-354-0307
ian.j.oneill@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov
2020-190
Source: Jet Propulsion Laboratory