An ageing United States weather satellite crucial to accurate predictions on the intensity and path of hurricanes could fail at any moment, and plans to launch a replacement have been pushed back seven years to 2016.
In a letter obtained by The Associated Press, the National Oceanic and Atmospheric Administration’s (NOAA) chief said the failure of the QuikScat satellite could bring more uncertainty to forecasts and widen the areas that are placed under hurricane watches and warnings.
If the satellite faltered, experts estimate that the accuracy of two-day forecasts could suffer by 10 per cent and three-day forecasts by 16 per cent, which could translate into miles of coastline and the difference between a city being evacuated or not. The satellite covers about 90 per cent of the globe’s oceans, experts say.
“We would go blind. It would be significantly hazardous,” said Wayne Sallade, emergency manager in Florida’s Charlotte County, which was hit hard by Hurricane Charley in 2004.
In the letter to a Florida congressman, NOAA Administrator Conrad Lautenbacher blamed the delays on technical and budget problems. Scientists said if QuikScat failed, they may have to rely on less accurate satellites.
Bill Proenza, director of the National Hurricane Center in Miami, said authorities “may have to err on the side of caution” in future forecasts.That means “more people disrupted, and more impact on the economy,” Proenza said. “On the other hand, we have to err on the side of the protection of life. And that’s how we would handle it.”
Lautenbacher said the replacement is part of a larger programme to update America’s weather satellites. The AP reported last week that other cuts in the programme have included scaled-back efforts to measure global warming from space.
Last year, forecasts were off an average of 111 miles (179 kilometres) two days in advance, a figure that has been cut in half over the past 15 years. But experts said that could grow 10 percent to 122 miles (196 kilometres) if the satellite is lost, causing the “cone of error” well known to coastal residents to expand.
Some scientists also complain that the technology planned for the replacement satellite is less precise for hurricane forecasting than what is currently flying.
QuikScat, launched in 1999 and designed to last two to three years, provides key data on wind speed and direction over the ocean. Weather aircraft and buoys can also obtain similar measurements near a storm, but they do not provide a constant flow of data as QuikScat does.
Last year, the satellite suffered a majorsetback – the failure of a transmitter used to send data to Earth about every 90 minutes. Now the satellite is limping along on a backup transmitter and has other problems.
The backup transmitter could last years, but there are no guarantees and no warnings when it is about to fail, said Robert Gaston, who works with the satellite at NASA’s jet propulsion laboratory.
Even if money were immediately available, a replacement satellite is estimated to take at least four years and cost approximately US$400 million to build.
If the satellite fails, the options are few. Other satellites have instruments to measure wind speed and direction over water, but they are less accurate.
A European satellite called ASCAT is available, but it does not give scientists as clear a picture as QuikScat because the distance between the readings it takes is larger. Using ASCAT would be like a person who wears glasses taking them off, seeing a once-sharp world blurred, said National Hurricane Center senior hurricane specialist Rick Knabb.