As the hurricane season churns toward its most potent period with storms affecting both Hawaii and Florida, superior aerial firepower is being deployed to provide advanced forecasting of the dangerous systems as they develop.
Last week, through a partnership between Boulder's National Center for Atmospheric Research and the National Oceanic and Atmospheric Administration, a Gulfstream-V aircraft took to the air to support hurricane forecasting.
That aircraft was rolled out for duty while NOAA's Gulfstream-IV was in the shop for unscheduled maintenance.
The plane, which is owned by the National Science Foundation, is capable of flying at high altitudes and utilizes the same specialized sensors as NOAA's G-IV. The instruments take key observations of atmospheric conditions for use by NOAA's National Hurricane Center.
Data show that those observations can improve hurricane tracking forecasts in the U.S. global weather model by roughly 15 percent during the 24 to 48 hours prior to landfall. Such forecasts also boost the accuracy in forecasting hurricanes' intensity.
The G-V, available for flights over both the Atlantic and Pacific oceans, flies above hurricanes at up to 45,000 feet, and also around the edges of storms. It is equipped with a dropsonde launch system and software similar to that of the G-IV.
"The G-V has superior range to the G-IV so we can actually stay airborne longer and stay above storms longer," said Lou Lussier, Research Aviation Facility project manager at NCAR's Research Aviation Facility based at Rocky Mountain Metropolitan Airport in Broomfield.
The Research Aviation Facility is part of NCAR's Earth Observing Laboratory.
"The G-V can also climb slightly higher than the G-IV," Lussier said. With the dropsondes taking readings from their high point to the surface, he added, "Since you get to higher altitudes than the G-IV, you get more depth in the atmosphere variables than with the G-IV."
Dropsondes, developed at NCAR in the 1970s, are parachute-borne sensors that record ambient temperature, humidity, pressure, wind direction and speed at select altitudes as they descend through the atmosphere.
The G-V were guided on its missions by NCAR pilots along preset flight tracks, releasing dropsondes about every 15 minutes. Data that was produced was processed by on-board NOAA technicians, and related to the agency's global telecommunications system for immediate input into the hurricane model forecasts.
While many people are somewhat familiar with research aircraft flying directly into the eyes of hurricanes to take readings in support of a forecast, the G-V's approach differs.
"What we're doing is more of a survey of the large-scale environment around the hurricane," Lussier said, which can produce data critical to tracking their intensity.
While Hurricane Hermine menaced Florida and Hurricane Lester was bearing down on Hawaii, the NCAR plane flew a pattern around Lester on Wednesday in the eastern Pacific. It then continued on to Honolulu and is standing by for additional flights if needed.
In a news release, Antonio Busalacchi, president of the University Corporation for Atmospheric Research — which manages NCAR for the NSF — hailed the latest manifestation of its cooperative relationship with NOAA.
"It's critical to have detailed measurements of the atmosphere around a hurricane in order to ensure that forecasts are as accurate as possible," Busalacchi said.
"NCAR and its research partners have a proven track record of improving predictions of dangerous storms. Consistent with our role of managing NCAR, we take very seriously our ability and responsibility to share our advanced resources in support of NOAA's mission to protect life and property."
At the end of May, NOAA's forecast for this hurricane season, which ends Nov. 30, was for a near-normal season in the Atlantic, with a 70 percent chance of 10 to 16 named storms.