Satellite to sharpen weather forecasting
It’ll cut lawn mower-like swaths around the globe, 500 miles above surface.
The Suomi satellite, a silent watchman on high that warned Florida of Hurricane Irma’s brutal march west, is in the twilight of its life.
A weather prediction marvel when launched six years ago, it will soon relinquish its guardianship duties to a whippersnapper with similar, but supercharged instruments meant to sharpen seven-day forecasts and save lives when Mother Nature hurls her worst.
The enhanced Joint Polar Satellite System-1, or JPSS-1, is the first in a new series of polar orbiting planetary monitors.
Scheduled for liftoff Tuesday, the $1.6 billion spacecraft can peer through clouds, see colors in thousands of different spectral bands, and get data to scientists twice per orbit — double the capability of the old Suomi.
The revolutionary GOES-16 weather satellite, which launched last year, stands as a motionless sentry 22,000 miles above Earth and with a focus on North America. The JPSS-1 is different in that it will cut lawn mower-like swaths around the globe just 500 miles from its surface.
lite’s ability to look at longer-term weather patterns was key in forecasting the track and intensity of Hur“Weather doesn’t know bor- ricane Irma, which made ders,” said Joseph Pica, direc- landfall near Cudjoe Key tor of the National Weather on Sept. 10 as a Category Service’s Office of Observa- 4 storm. tions. “The humidity and Florida Gov. Rick Scott rainfall on the coast of China declared a state of emergency today could be over the Pacific a full five days ahead of Irma’s Northwest in several days.” landfall, with President Don-
Polar orbiters have circled ald Trump approving emer- the Earth for decades. The gency declarations for Flor- Suomi launch in 2011 marked ida, Puerto Rico and the U.S. a huge advancement in tech- Virgin Islands a day later. nologies, but it was only a Six million Floridians evac- test, helping scientists bet- uated ahead of the storm, a ter understand how to use massive undertaking Pica the equipment onboard and said was possible because how the new data affected of the early forecasts. weather models. “We’re really proud of
A hefty amount — 85 perwhat happened with Irma cent — of the data that goes because of all the time and into global weather modnotice everyone got,” Pica els comes from polar orbitsaid. “The track and intensity ers. And whereas GOES-16 forecasts are largely based looks deeply at what is hap- on polar orbiters.” pening now in the atmoThere have been misses sphere or just upstream, also. In September 2015, the polar orbiter is key to when Suomi was operational, medium-range forecasts with Tropical Storm Erika trig- instruments that measure gered a state of emergency as slices of the atmosphere sim- Florida found itself in a five- ilar to the information gath- day forecast track that also ered by the daily weather called for Erika to strengthen balloon launches made at to a hurricane. Instead, Erika the nation’s 120 weather fizzled over Hispaniola. forecasting offices. “The JPSS-1 brings new
The JPSS-1, which will technology that will be able circle the globe 14 times per day, also will monitor sea-surface temperatures, ocean color, sea ice cover, volcanic ash spread and wildfires.
“Having the ability to look through the atmosphere vertically is important,” said Dan Kottlowski, a senior meteorologist at the Pennsylvania-based AccuWeather. “It gives us a lot of information about how Earth is working.”
Pica said the Suomi satel- to significantly improve the confidence we can provide in the forecast,” Pica said.
The five key instruments on the JPSS-1 include an ozone mapper, infrared imager, an infrared sounder (which measures temperature and moisture content in the atmosphere), a microwave sounder to measure radiation, and a radiometer to collect information on snow, clouds, fog, fire, smoke and dust.
The Melbourne-based Harris Corp. built the Cross-track Infrared Sounder, which slices up the atmosphere to measure temperature and moisture at different elevations.
Harris Chief Solutions Engineer Ron Glumb said a similar instrument is on the Suomi.
“The one flying now is very good already, the one on JPSS will be even better,” Glumb said.
The JPSS-1 is scheduled for launch Tuesday from California’s Vandenberg Air Force Base at 4:47 p.m. EST. NASA-TV will cover the launch live at www.nasa. gov/ntv.