Saildrone 1045, one of the five drones PMEL and AOML deployed in the western Atlantic was steered into position to intercept Category 4 Hurricane Sam on September 30, 2021 to record critical data. The encounter required precise interpretation of hurricane forecasts and tight collaboration with Saildrone pilots. The saildrone measured one-minute sustained wind speeds of up to 90.6 miles per hour (40.5 m/s) with wind gusts up to 126.5 mph (56.5 meters/second), waves exceeding 46.4 feet (14.2 meters), and saturated air near the surface. The saildrone was in the hurricane eye next to the eyewall at 16:00 UTC / 12:00 EDT and was in sustained hurricane-force winds (at least 75 mph) for about two hours straight. The first ever drone camera images and video show a large amount of sea spray from the ocean surface and are a frightening display of the power of tropical cyclones.
This is the first time that sea surface conditions near a hurricane eye were observed by an uncrewed surface vehicle. Its success is built upon years of partnership between NOAA and Saildrone, Inc. with testing in progressively more hostile environments and 5 years of innovative engineering on the platform, sensors, and data processing, months of preparation leading to the deployment, and dedicated efforts of operating saildrones by the NOAA science team and Saildrone pilots during the deployment. This animation shows how the saildrone intercepted Hurricane Sam, and this animation, created by scientists at NOAA AOML, shows how the saildrone was positioned to intercept Hurricane Sam alongside saildrone observations of Hurricane Sam.
Prior to hurricane Sam, the NOAA saildrones also measured tropical storms Peter (9/21/2021), Henri (8/20/2021), Grace (8/17/2021) and Fred (8/13/2021). Read more about these encounters on the mission blog: https://www.pmel.noaa.gov/saildrone-hurricane2021/mission_blog.html
PMEL in the News
For the first time, a surface drone captured footage of a Category 4 hurricane’s 50-foot waves and 120-mph winds. Chris Meinig is quoted.
A new study showed nighttime air in the western U.S. is getting drier and warmer, potentially prolonging fire activity. Andy Chiodi is quoted.
Local evidence of the cataclysm has literally washed away over the years. But Oregon’s Douglas firs may have recorded clues deep in their tree rings. Bob Dziak is quoted.
This map shows heat content anomalies (differences from the long-term average)—in the top 700 meters (~2,100 feet) of the global ocean. Positive anomalies mean the ocean gained heat in 2020 (orange); negative anomalies mean the ocean lost heat energy (blue) in 2020. NOAA Climate.gov image, based on data provided by John Lyman (UH JIMAR/PMEL)
The 31st annual State of the Climate report confirmed that several markers such as sea level, ocean heat content, and permafrost in 2020 once again broke records set just one year prior. 2020 was also among the three warmest years in records dating to the mid-1800s, even with a cooling La Niña influence in the second half of the year. New high... more