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Figure 1 | Figure 2 |
These two images show Hurricane Isabel as viewed by AIRS and each of the
two SeaWinds scatterometers on the ADEOS-2 and QuikScat satellites, all
JPL-managed experiments. AIRS data are used to create global
three-dimensional maps of temperature, humidity and clouds, while
scatterometers measure surface wind speed and direction.
Figure 1 shows Isabel on September 13, 2003, when it was a Category 5
storm threatening the Caribbean and southern United States. At the time
Isabel was the strongest Atlantic storm since hurricane Mitch killed
thousands in central America in 1997. The red vectors in the image show
Isabel's surface winds as measured by SeaWinds on ADEOS-2, and the
background colors show the temperature of clouds and surface, as viewed
in the infrared by AIRS. The hurricane's powerful swirling winds are
apparent. These winds circle the hurricane's eye, seen as the red dot
near the middle top of the image. Light blue areas shows adjacent cold
clouds tops associated with strong thunderstorms embedded within the
storm.
Figure 2 shows Isabel as it approached landfall on the outer banks of
North Carolina on September 18. The hurricane weakened in the five days
since the earlier image was observed, as indicated by a less clearly
defined eye. Nevertheless, it was still a powerful storm. The winds
blowing onshore north of the eye knocked over trees, blew roofs off
buildings, and drove large waves that breached the coastal barrier
islands in many places. Water, transportation and power are still not
fully restored to many of the areas in the image. The winds apparently
blowing away from the eye of the storm are an artifact of one of the
hurricane's other destructive phenomena: rain. The darkest blue clouds
observed by AIRS show the most intense thunderstorms, and hence the
heaviest rains. Hard rain fools the the SeaWinds on QuikSCAT system into
thinking the winds are blowing directly across the viewing 'swath.'
Nevertheless, the two systems give a consistent picture of this storm.