Satellite images: Hook echoes, debris and damage

May 30, 2011 By Kim Newton
Radar image of tornado near Tuscaloosa, Ala., on April 27, 2011. Credit: (NASA/SPoRT)

This image shows the radar reflectivity from the National Weather Service Doppler Radar in Birmingham, Ala. at 5:10 p.m. CDT on April 27, 2011, as a supercell thunderstorm moved across the city. The radar reflectivity is overlaid upon Advanced Spaceborne Thermal Emission and Reflection Radiometer, or ASTER, satellite data acquired on May 4, 2011, showing the damage track resulting from for the EF-4 tornado associated with the storm as it passed through the city and continued northeast toward Birmingham, Ala.

The complex pattern of ASTER data indicate variability in land use characterized by colors in this three-channel composite. Here, the ASTER data shows the tornado damage scar -- aqua in color -- left by the violent tornado as damage disrupts other, more typical land use patterns, while shows the classic "hook echo" signature associated with the rotating storm updraft. On the lower end of the hook is a round region of enhanced radar reflectivity -- near the Interstate 359 marker -- associated with the surface debris lofted by the tornadic winds. This "debris ball" signature corresponds to the ASTER tornado damage track in this and subsequent .

Radar image of tornado near Phil Campbell, Ala., on April 27, 2011. Credit: NASA/SPoRT

Similar to the radar and satellite composite imagery provided for the Tuscaloosa, Ala. tornado, this image from Phil Campbell, Ala. shows radar reflectivity from the Doppler Radar at Columbus Air Force Base, Miss. at 3:33 p.m. CDT as a strong supercell departed Marion County, Ala. and entered Franklin County, Ala. As in the Tuscaloosa case, the “hook echo” signature is apparent with enhanced radar reflectivity along the damage scar indicated by Advanced Spaceborne Thermal Emission and , or ASTER , likely corresponding to lofted debris. Damage in the Phil Campbell area was rated as an EF-5 and continued northeast before weakening slightly in the Mount Hope, Ala. area. The damage scar continues southwest into Marion County, Ala., through the community of Hackleburg, Ala. -- not shown -- and further to the northeast as the storm continued into southwestern Lawrence County, Ala.

These images were created by the NASA Short-term Prediction Research and Transition, or SPoRT, Center at Marshall Space Flight Center in Huntsville, Ala., using ASTER data provided courtesy of NASA's Goddard Space Flight Center in Greenbelt, Md.; the United States Geological Survey Land Processes Distributed Active Archive Center in Sioux Falls, S.D., Japan's Earth Remote Sensing Data Analysis Center in Tokyo, Japan; the Ministry of Economy, Trade and Industry, along with the Japan Research Observation System Organization. Final ASTER imagery were produced using resources of the Nebula Cloud Computing Platform, tiled, and displayed within Google Earth. Radar imagery were provided by the NOAA National Climatic Data Center's NEXRAD Archive in Asheville, N.C. Storm survey information was provided by the National Weather Service Forecast Offices in Birmingham and Huntsville, Ala.

Explore further: Satellites catch the birth of two volcanic islands

Related Stories

NASA satellite observes damage path of april tornadoes

May 09, 2011

Recent images of the April 27 storm damage path have been captured by NASA's Terra satellite, part of NASA's Earth Observing Satellite system, or EOS. An instrument aboard Terra, called Advanced Spaceborne ...

Recommended for you

Satellites catch the birth of two volcanic islands

3 hours ago

The birth of a volcanic island is a potent and beautiful reminder of our dynamic planet's ability to make new land. Given the destruction we've seen following natural events like earthquakes and tsunamis in t ...

Uncovering diversity in an invisible ocean world

4 hours ago

Plankton are vital to life on Earth—they absorb carbon dioxide, generate nearly half of the oxygen we breathe, break down waste, and are a cornerstone of the marine food chain. Now, new research indicates ...

Evolution of the Antarctic ice sheet

6 hours ago

ULB study sheds a new light on the stability of the Antarctic ice sheet. It shows for the first time that ice rises (pinning points that keep the floating parts of ice sheets in place) are formed during the transition between ...

Severe ozone depletion avoided

May 26, 2015

We are already reaping the rewards of the Montreal Protocol, with the ozone layer in much better shape than it would have been without the UN treaty, according to a new study in Nature Communications.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.