Low-light imagery is being used to assist emergency management agencies in the aftermath of Hurricane Katrina
ABOVE: LOS ANGELES AFB, Calif. – These nighttime satellite images show areas of the Gulf Coast without power (shown in red) following the passage of Hurricane Katrina versus areas with normal lights (yellow). Comparing an annual composite against data from one night makes this nighttime change image. The composite is produced using cloud-free portions of low-light imaging data acquired by the Defense Meteorological Satellite Program over one year. In this case, the composite is made using data from 2004 and is compared with data from Aug. 30, 2005. Clouds are displayed in blue. As power is restored, areas in red should revert to yellow. (Images courtesy of National Geophysical Data Center).
BELOW: LOS ANGELES AFB, Calif. – These images show Defense Meteorological Satellite Program nighttime imagery of the Gulf Coast Region Aug. 31 compared to a satellite pass over the area Aug. 28 and again Sept. 7 – before and after Hurricane Katrina’s impact on the area’s power grid. (Images courtesy of Air Force Weather Agency)
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LOS ANGELES AFB, Calif. – Low-light imagery is being used to assist emergency management agencies in the aftermath of Hurricane Katrina through U.S. Air Force Space Command’s Space and Missile Systems Center Defense Meteorological Satellite Program satellites.
Agencies can assess damage and track repair progress by comparing “lights at night” images taken before and after a disaster. This imagery provides data on human activity as indicated by city and industrial lights.
DMSP satellites meet military requirements for worldwide space and terrestrial weather information. Through these satellites, military weather forecasters detect developing patterns of weather, track existing weather systems over remote areas and alert civil and military communities of anticipated hazards in space.
Data from these satellites helps identify, locate and determine intensity of severe weather such as thunderstorms, hurricanes and typhoons. It can also be used to form 3-D cloud analyses, which are the basis for computer forecast models that meet unique military requirements. Additionally, space environmental data is used to assist high-frequency communications, over-the-horizon radar and spacecraft drag and re-entry tasks.
All of this information aids military commanders in making decisions. Data obtained through DMSP supports launch, en route, target and recovery portions of a wide variety of strategic and tactical missions.
“Meteorological satellites play an important role in observing the environment and predicting how the environment will change with time,” said Col. John Wagner, DMSP system program office director. “Now in its fourth decade of service, the DMSP has proven itself to be a valuable tool in supporting military operations on land, at sea, in space and in the air.”
DMSP satellites also provide support to the civil weather system.
“The unique nighttime visual imagery is used for storm damage assessment, detecting forest fires, volcanic activity and lightning,” said Colonel Wagner. “Our microwave data is used in measuring sea ice coverage and age and in numerical weather forecast models, and our space environmental sensors contribute to predictions of communication and power line outages.”
DMSP satellites provide meteorological data in real time to Air Force, Army, Navy and Marine Corps tactical ground stations and Navy ships worldwide. This data is also stored in recorders on the satellites for later transmission to one of four ground stations located near Fairbanks, Alaska; New Boston, N.H.; Thule Air Base, Greenland; and Kaena Point, Hawaii.
From these ground stations, data is relayed to the Air Force Weather Agency at Offutt Air Force Base, Neb., and to the U.S. Navy's Fleet Numerical Meteorological and Oceanographic Center at Monterey, Calif., where this information is used to compile numerous worldwide weather and space environmental products. The Air Force and Navy weather centers distribute these products to the Department of Defense and other government agencies. The National Hurricane Center issues hurricane warnings in the continental United States, using DMSP data.
The Operational Linescan System detects low levels of visible, near infrared radiance at night, including clouds illuminated by moonlight, plus lights from cities, towns, industrial sites, gas flares and ephemeral events such as fires and lightning-illuminated clouds.
During the first 20 years of DMSP, no digital archive of nighttime OLS data was maintained. In 1992, DoD and NOAA established a digital archive for the DMSP program at the NOAA National Geophysical Data Center. NGDC researchers have now used the digital data to produce a “city lights” dataset for the United States and other areas of the world.
NGDC's Earth Observation Group produced a similar series of satellite images showing the extent of power outage following Hurricane Katrina. Nighttime lights data acquired by the DMSP OLS and overlaying individual orbits of OLS nighttime data on the stable lights product from 2004 generated the power outage images.
In the imagery, areas with power outage are red; areas with power are yellow; and clouds are blue. On Aug. 30, a large area of power outage can be observed in southeastern Louisiana and the southern half of Mississippi and, in succeeding nights, the area of power outage contracts. These NGDC products were provided to the Department of Homeland Security and the Federal Emergency Management Agency. FEMA included the image in the Sept. 1 presidential briefing on Katrina.
While DMSP does not distribute data directly to the emergency management agencies assisting with Hurricane Katrina, information derived from DMSP imagery is distributed by the Air Force Weather Agency, U.S. Navy Fleet Numerical Meteorological and Oceanographic Center and “tactical” terminals – portable systems which enable weather satellite data to be used more quickly by joint warfighters in the field. In this case, imagery was provided by AFWA to U.S. Air Force Northern Command, North American Aerospace Defense Command and the U.S. Air Force Operations Group at the Pentagon.