Small satellites could improve hurricane forecasting
- By Matt Leonard
- Nov 15, 2016
NASA will launch a constellation of eight small satellites next month in an effort to improve wind measurements inside hurricanes. This data will help scientists monitor and predict rapid changes in hurricane intensity, which will prove vital to public safety, NASA officials said.
The Cyclone Global Navigation Satellite System (CYGNSS) constellation will attempt to alleviate two of the current challenges with measuring wind speed inside hurricanes: interference with rain and the time it takes to collect measurements.
“The primary limitation with our current ability to forecast how strong a hurricane is going to be in the future is our inability to see what’s going on in the inner core of the hurricane,” said Chris Ruf, the CYGNSS principal investigator at the University of Michigan, Ann Arbor. “We can forecast where a hurricane is going to go fairly well because that’s determined by environmental fields away from the hurricane that are easy to measure with existing satellites, but we can’t measure what’s happening in the center of the hurricane, which is what drives its rapid intensification.”
The current satellite-based technology used to measure wind speeds inside hurricanes uses a wavelength that is subject to interference from large raindrops, Ruf said. Additionally, satellites took three days of orbiting to get full earth data. The eight CYGNASS satellites can record 32 ocean surface wind measurements per second. The faster flow of more revealing data will make prediction models more accurate, NASA said.
CYGNSS will use two sets of GPS signals from existing satellites to determine wind speed. The first signal is sent directly from a satellite to CYGNASS to help pinpoint its position. The other signals are reflected off the ocean’s surface, where they measure the roughness of the waves, from which wind speed can be deduced.
The solar panels on the exterior of the eight satellites will produce the 60 watts of power needed to collect data, run measurements and send data back to earth.
CYGNSS is the first complete orbital mission competitively selected by NASA's Earth Venture program, which focuses on low-cost, rapidly developed, science-driven missions to enhance earth science understanding.
CYGNSS will be sent into orbit Dec. 12.
Matt Leonard is a former reporter for GCN.