The Cyclone Global Navigation Satellite System will fly for another 19 months. NASA decided to extend the mission because the project provides fresh insight into forecasting hurricane tracks and, more importantly, hurricane intensity. That insight may help save lives.
The satellite system was launched in December 2016 to collect wind speed data using the unconventional method of measuring GPS waves bouncing of the Earth. Until CYGNSS, the scientific community couldn’t measure wind speed under heavy clouds and rain, or in a hurricane, unless they flew a specially-outfitted plane—a Hurricane Hunter—into it.
The data has been modeled, and project scientists say it improves hurricane track forecasts, but more importantly, it improves the hurricane-intensity forecast. Because scientists have lacked routine and frequently updated data from inside hurricanes, they have not improved intensity forecasting for decades. Intensity and storm surge cause most of the property damage and loss of life.
“The intensity forecasts have definitely improved,” said Chris Ruf, CYGNSS principal investigator and University of Michigan professor. “When the forecasts are good, we don’t add much value. When they’re bad, we add value.”
CYGNSS cuts down on surprises. That’s especially valuable with storms that develop unusually like last year’s Hurricane Irma, which had winds circling off kilter.
The National Oceanic and Atmospheric Administration has watched the new method develop, and Ruf hopes they decide to use their data in predictive forecasts.
“In the end, that’s the sign of success is that, either with this mission or a follow on mission, just to show that this technique adds value to information about the hurricane in the present to help them forecast them in the future,” he said.
The data set and process are just a couple of ways the mission has proved unconventional.
At $152 million, it was fairly inexpensive. The NOAA GOES-R, which launched about a month before CYGNSS, was part of a series valued at $1.4 billion. It is a constellation of eight satellites, all being run outside of NASA.
Science is run out of the University of Michigan. The satellites are operated out of San Antonio-based Southwest Research Institute, where the suitcase-size satellites were built, which is also unconventional because SwRI had at the time never built a satellite.
“It’s a remarkable achievement,” said Charles Webb, NASA program executive for operating missions in Earth science, “to be able to do that outside the auspices of NASA where it has traditionally been done.”
That isn’t to say the mission has been without complications. The learning curve for the new collection method took longer than expected, and scientists had to adjust to things outside their control, like the variable strength of GPS signals. Sometimes the Air Force would adjust its signal strength without warning.
CYGNSS succeeded in meeting its science requirements, and, according to Webb, the decision to extend was a relatively easy one. Primarily, NASA is interested in more wind speed and storm data, but the team did propose expanding into land applications as well.
The satellites’ data has shown promise in flood forecasting, commercial agriculture and tropical wind research.
Paul Flahive can be reached at paul@tpr.org or on Twitter @paulflahive.
