Power outages after Hurricane Ian
28–29 September 2022, Hurricane Ian roared through Florida as one of the most powerful storms ever to make landfall in the state. The Category 4 hurricane brought sustained winds of 150 miles (240 kilometers) per hour and several feet of storm surge to Florida’s southwest coast before dumping more than a foot of rain across the state.
In the hours after the storm, millions of home and business customers lost electricity and light. The Visible Infrared Imaging Radiometer Suite (VIIRS) at NOAA–NASA Satellite of the Finnish nuclear power plant captured views of some of these losses as they appeared on September 30, 2022.
The images above and below focus on the Fort Myers and Bradenton/Sarasota metro areas, which were the hardest hit communities. VIIRS has a twilight sensor – a day-night area that measures nighttime light emissions and reflections. Researchers Black marble project At NASA’s Goddard Space Flight Center, Science Systems and Applications, Inc. (SSAI) and the University of Maryland, College Park (UMD) processed VIIRS data to show the lights before and after Ian passed through cities. Data from September 30 were compared to the pre-storm composite (August) and overlaid with data collected by land cover. Landsat 8 and 9.
“Since disasters often affect an entire region, the ability to record widespread power outages in a distributed energy system is very useful for damage assessment,” said Ranjay Shrestha, a researcher at SSAI’s Black Marble team. “Combining socio-economic and demographic data with metrics from nighttime light will help us understand the interaction between power restoration rates and vulnerable populations.”
By informal assessments, about 580,000 of Florida’s 11 million business and residential customers were without power on the afternoon of Oct. 3, compared to about 2.7 million on Sept. 29. The outages were concentrated in Lee, Charlotte and Sarasota counties in the southwestern part of the state. Thousands of utility workers from 34 states traveled to Florida to help restore power lines and other equipment.
The VIIRS day/night band makes it possible to distinguish the intensity of lights and detect their changes. Aid organizations sometimes use night images to identify areas that need the most help and support. “Our team has developed standardized approaches to outage and restoration assessment to help local communities improve resilience to the effects of climate change and extreme weather events,” said Zhuosen Wang, a researcher at the University of Maryland and principal investigator of the Black Marble product. .
Accuracy is critical in research conducted with night lights. Unprocessed images can be misleading because moonlight, clouds, pollution, seasonal vegetation—even the satellite’s position—can change how light is reflected and distort observations. The Black Marble team’s processing takes such changes into account and filters stray light from sources other than electric lights.
NASA Earth Observatory images by Joshua Stevens using Black Marble data courtesy of Ranjay Shrestha/NASA Goddard Space Flight Center, Landsat data US Geological Surveyand information about the destination OpenStreetMap. Story by Michael Carlowicz.