After pounding North Carolina and Virginia on Aug. 27, Hurricane Irene made a second landfall near Little Egg Inlet, N.J., early Sunday morning, Aug. 28, still as a category one hurricane with maximum sustained winds of 75 mph (120 kilometers per hour). It then weakened slightly before making a third landfall over Coney Island, N.Y. as a 65-mph (100-kilometer-per-hour) tropical storm. Irene's heavy rains, winds and storm surge are causing widespread problems throughout the U.S. mid-Atlantic and Northeast.
This infrared image of Irene was taken by the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft at 2:47 a.m. EDT on Aug. 27, a few hours before the storm's second landfall in New Jersey.
The AIRS data create an accurate 3-D map of atmospheric temperature, water vapor and clouds, data that are useful to forecasters. The image shows the temperature of Irene's cloud tops or the surface of Earth in cloud-free regions. The coldest cloud-top temperatures appear in purple, indicating towering cold clouds and heavy precipitation. The infrared signal of AIRS does not penetrate through clouds. Where there are no clouds, AIRS reads the infrared signal from the surface of the ocean waters, revealing warmer temperatures in orange and red.<
The Atmospheric Infrared Sounder, AIRS, in conjunction with the Advanced Microwave Sounding Unit, AMSU, senses emitted infrared and microwave radiation from Earth to provide a three-dimensional look at Earth's weather and climate. Working in tandem, the two instruments make simultaneous observations all the way down to Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, three-dimensional map of atmospheric temperature and humidity, cloud amounts and heights, greenhouse gas concentrations, and many other atmospheric phenomena. Launched into Earth orbit in 2002, the AIRS and AMSU instruments fly onboard NASA's Aqua spacecraft and are managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.
More information about AIRS can be found at http://airs.jpl.nasa.gov.More on NASA's hurricane research and Irene is online at NASA's hurricanes/tropical cyclones website http://www.nasa.gov/mission_pages/hurricanes/main/index.html and the JPL TC-IDEAS hurricane website http://hurricanes.jpl.nasa.gov.