Alaska weather forecasters promise better predictions with new polar satellites

Alaska weather experts are predicting better forecasts ahead, once a $1.6 billion satellite begins looping the planet's poles next week. Trailing a similar satellite, it will vastly improve detection of everything from nascent wildfires to approaching storms and even nighttime fog.

The increased data and clear images will benefit weather prediction globally, said officials at the National Oceanic and Atmospheric Administration. It will have particular importance in Alaska for pilots, mariners and backcountry travelers trying to avoid hazards, they said in a conference call with reporters this past Tuesday.

NOAA 20, as the satellite will be called in orbit, is scheduled to launch no earlier than Tuesday from Vandenberg Air Force Base in California. The launch was delayed four days because of battery problems on the load-carrying rocket.

Alaska has "many forecast challenges," with limited observation sites spread across vast areas, said Nate Eckstein, a meteorologist with the National Weather Service in Alaska.

The new satellite, joining its prototype cousin launched in 2011, will go a long way in closing that gap, he said. For Alaska, they're a tremendous improvement over satellites that orbit the equator and struggle to see north of the Alaska Range.

Officials said they are the first state-of-the-art, polar-orbiting satellites.

The prototype satellite launched six years ago provided a test run for the Joint Polar Satellite System program, a collaboration between NOAA and NASA.

Under the program, four new polar-orbiting satellites will be launched about every five years through 2031, including the one Tuesday. New satellites will replace old ones that reach the end of their operational lives, said Mitch Goldberg, a NOAA scientist working on the program.

The satellites fly close to Earth compared to other satellites, Goldberg said. They use microwaves to see at night through clouds, detecting images of sea ice or other features below. They will use reflected moonlight to capture detailed surface images.

One benefit is the level of atmospheric data the polar-orbiting craft gather, such as for temperatures and moisture. They'll contribute to "vertical profiles" of the atmosphere that are now central to weather prediction, including the accurate five-day forecast that predicted Hurricane Sandy would slam into the New Jersey coast in 2012, Goldberg said.

The improved forecasting accuracy will give authorities better information days earlier, helping make calls on evacuations, such as when a Bering Sea storm approaches a village, Eckstein said.

Predictions about the direction of volcanic ash will improve. Small wilderness fires will be spotted earlier, offering clues about their potential to become big blazes. Fog detection in mountain passes will benefit small-plane pilots seeking safe routes, he said.

"This ability to detect small areas in tight places where our general aviation aircraft are operating is really key," Eckstein said.

Together, the two satellites will see all of Alaska eight times daily, said Goldberg.

Carl Dierking of the University of Alaska's Geographic Information Network of Alaska, which shares satellite data with the weather service, said the two polar-orbiting satellites will increase the number of clear, round-the-clock views of land and water.

"You can see tremendous detail," Dierking said. "Where there's snow versus no snow, flooding versus fog. All these things are important if you're traveling in remote locations. The more we can help monitor hazardous weather conditions in Alaska, the better off we are."

The satellites will boost weather-reporting capabilities that are lacking in Alaska, Dierking said.

Florida has several weather service forecast offices for an area the size of the Alaska Panhandle. Alaska has just three, in Anchorage, Fairbanks and Juneau.

"We're doubling our ability to see (visible light) at night, and that's a real advantage for the Far North," he said.