NASA Distributed Active Archive Center (DAAC) at NSIDC

AMSR-E/Aqua Data

Advanced Microwave Scanning Radiometer - Earth Observing System Sensor on the NASA Aqua Satellite

AMSR-E Images of Hurricane Katrina

Hurricane Katrina struck the central Gulf Coast of the United States in late August 2005, resulting in the death of nearly 1800 people and the displacement of more than a quarter million. It was the most costly natural disaster to hit the U.S. with the estimated damages reaching $125 billion. Katrina was one of the strongest storms to impact the coast of the U.S. in over 100 years. The storm made landfall along the Gulf Coast on 29 August 2005 as a strong Category 3 hurricane on the Saffir-Simpson scale, with wind speeds reaching 127 mph.

The Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) sensor, aboard the NASA Aqua satellite, captured images of the hurricane as it tracked across the Gulf of Mexico. AMSR-E is a a twelve-channel, six-frequency, passive-microwave radiometer that is well-suited for studying rainfall, oceans, soil moisture, and polar sea ice.

The Level-2 and Level-3 ocean products provide daily, weekly, and monthly sea surface temperature (SST) at 38 and 56 km resolutions and near-surface wind speed in 21 and 38 km resolutions. The SST algorithm utilizes the 6.9 through 36.5 GHz AMSR-E channels while the wind algorithm uses the 10.7 through 36.5 GHz channels (Wentz and Meissner 2000).

The Level-2 Rain product provides instantaneous measurements of rain rate and rain type, generated from Level-2A brightness temperatures (AE_L2A). The Goddard Space Flight Center (GSFC) Profiling algorithm determines rain rate and rain type over ocean areas, and a Modified GSFC Profiling algorithm over land (Kummerow and Ferraro 2007).

Sea Surface Temperature

SST, 23 August
23 August 2005
SST, 27 August
27 August 2005
SST, 29 August
29 August 2005

The above images from the NASA/Goddard Space Flight Center Scientific Visualization Studio show the cold water trail left by Hurricane Katrina.  The colors on the ocean represent the sea surface temperatures, and satellite images of the hurricane clouds are laid over the temperatures to clearly show the hurricane positions. Orange and red depict regions that are 82 degrees Fahrenheit and higher, where the ocean is warm enough for hurricanes to form. Hurricane winds are sustained by the heat energy of the ocean, so the ocean is cooled as the hurricane passes and the energy is extracted to power the winds. The sea surface temperatures are 3-day moving averages based on the AMSR-E instrument, while the cloud images were taken by the Imager on the GOES-12 satellite.

Katrina reached peak strength on 28 August 2005 and made landfall on 29 August 2005. The following AMSR-E browse images show daily Level-2 instantaneous measurements of rain rate in mm/hr and daily Level-3 wind speed over ocean in m/s at 21 km resolution for 28-29 August 2005.

 

Rain Rate

Rain Rate, 23 August
 
Rain Rate, 28 August
28 August 2005
Rain Rate, 29 August
29 August 2005

     
 

Wind Speed

Wind Speed, 23 August
 
Wind Speed, 28 August
28 August 2005
Wind Speed, 29 August
29 August 2005

Browse images courtesy of Matt Smith at the Information Technology & Systems Center, University of Alabama at Huntsville.