A powerful weather satellite will improve forecasts


The current three-to-seven-day forecast that Americans rely on to plan everything from weekend picnics to hurricane evacuations relies heavily on constant updates from satellites that orbit the Earth’s poles. to measure temperature, humidity and a host of other variables that define the evolution of the planet. – changeable weather.

Early Tuesday, NASA plans to launch the first of four state-of-the-art polar orbiters for the The National Oceanic and Atmospheric Administrationa $1.6 billion weather satellite that will monitor the entire planet as it orbits below, providing computer models with the data they need to make increasingly accurate predictions.

Forecasters and climatologists say it’s hard to overstate the importance of the new satellite, which will join a once experimental and now aging weather station already in polar orbit to ensure uninterrupted service.

Steve Volz, director of satellite and information service at NOAA, said the first Joint Polar Satellite System The spacecraft — JPSS 1 — will use “the best technology NOAA has ever used operationally in polar orbit to capture more precise observations of Earth’s atmosphere, land and waters that will help improve NOAA’s vital weather forecasts”.

The program’s chief scientist, Mitch Goldberg, said JPSS 1 will deliver that data six times faster than previous satellites could with up to six times the resolution.

“That means we’re providing forecasting models with much more accurate data,” he said. “We also have an imager that can detect forest fires, volcanic eruptions, floods, sea ice, droughts, etc., another instrument that observes ozone and another that observes the radiation balance of the Earth.”

In addition to improving forecasts, he added, “JPSS can observe ocean and coastal water quality, which are important to fisheries and coastal communities, JPSS can observe vegetation and precipitation, all of which are two important for agriculture”.

“JPSS will provide satellite products for ice detection and thickness needed for safe navigation around Alaska and the Arctic. We can see volcanic eruptions, ash clouds, which have of course an impact on aviation, we can see small fires before they become bigger to give firefighters a head start.

The National Oceanic and Atmospheric Administration plans to spend $11.3 billion to develop instruments and build, launch and operate a fleet of four Joint Polar Satellite System spacecraft through 2038.

The relatively low-altitude Polar Orbiters will work in concert with the more familiar Geostationary Operational Environmental Satellites – GOES – weather stations that provide hemispherical views from their elevated perches 22,300 miles above the equator.

But it’s the polar orbiters that provide the lion’s share of the data needed for the computer models used by forecasters.

A view of Hurricane Irma as it passed through Barbuda, as seen by the polar-orbiting Suomi NPP satellite. The JPSS 1 satellite launch on Tuesday will join the aging Suomi nuclear power plant to provide uninterrupted service.


Built by Ball Aerospace, JPSS 1 is scheduled to launch from Vandenberg Air Force Base, Calif., at 1:47 a.m. PST (GMT-8) Tuesday atop a United Launch Alliance Delta 2 rocket. The satellite’s $1.6 billion price includes the cost of the rocket and operational support.

The Delta 2, fitted with nine solid-fueled belt thrusters for additional lift-off power, will propel JPSS 1 into a 512-mile high polar orbit that will repeatedly carry the spacecraft across the equator at 1:30 p.m. local time. . After three months of testing and verification, the satellite will enter normal operation.

JPSS 1 will share its orbit with Suomi Nuclear Power Plant, a satellite launched in 2011 to serve as a test bed for the sophisticated instruments of the Joint Polar Satellite System spacecraft. While launched as a research satellite, Suomi NPP is now considered operational.

Once the experimental instruments aboard the Suomi nuclear power plant proved their worth during this year’s hurricane season when Harvey, Irma and Maria caused widespread flooding and devastation. In all three cases, NOAA satellites supported accurate forecasts that gave residents time to prepare.

Lin-Manuel Miranda in Puerto Rico


“In all of these events, the death rates were far lower than previous historic storms, such as Katherine“, said Louis W. Uccellini, director of the National Weather Service. “The well-coordinated preparation decisions for these storms were based on forecasts that rely on global numerical prediction systems.

“The forecasts you have seen are impossible without the robust, high-quality global measurements of the atmosphere needed to initialize our numerical weather prediction systems. Polar satellites are the only way to obtain global measurements of temperature and humidity, and they are the backbone of the global observing system that we use to make these predictions of extreme events.”

JPSS 1 is equipped with five state-of-the-art instruments:

  • The advanced technology microwave sounder for measuring atmospheric temperature and humidity, day or night, regardless of cloud cover; built by Northrup Grumman Electronic Systems.
  • The Cross-Track Infrared Sounder, designed to collect 2,000 channels of highly accurate temperature and humidity readings in open sky areas; built by Harris Corp.
  • The Visible Infrared Imaging Radiometer Suite, which will collect visible light and infrared images for global land, atmosphere and ocean observations; built by Raytheon Co.
  • The Ozone Mapping and Profiler Suite, which will measure ozone concentrations in the atmosphere and monitor the “ozone hole” over Antarctica; built by Ball Aerospace and Technology Corp.
  • Clouds and Earth’s Radiant Energy System, or CERES, which will monitor how the Earth absorbs and reflects solar radiation; built by Northrop Grumman Aerospace Systems.

“JPSS Constellation satellites collect global measurements of atmospheric, land and ocean conditions, including sea and land surface temperatures, vegetation, clouds, precipitation, snow and ice cover, locations of fires and smoke plumes, atmospheric temperature, water vapor and ozone,” according to the JPSS website.

“JPSS provides key observations for the country’s essential products and services, including forecasting extreme weather conditions such as hurricanes, tornadoes and blizzards days in advance, and assessing environmental risks such as droughts. , forest fires, poor air quality and harmful coastal waters.”

The JPSS system “will ensure the continuity of critical observations of the Earth on a global scale, including our atmosphere, our oceans and our lands until 2038”.


Comments are closed.