A View Inside Hurricane Florence
In April 2006, a Boeing Delta II rocket launched CloudSat, along with a second satellite, CALIPSO, into space on two- and three-year missions to study the world's clouds and a mix of airborne particles called aerosols.
Twelve years later, both satellites are still chugging along, though it has not always been easy going in recent years. In CloudSat's case, only a series of orbital maneuvers and other technical fixes have kept the satellite returning useful science data in the twilight years of its mission.
One of CloudSat's most recent acquisitions—a view of the inner structure of Hurricane Florence as the storm took aim for the Carolinas—underscores the mission's scientific value. This natural-color image shows how Hurricane Florence appeared from above to the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite on September 11, 2018. The second image, acquired by CloudSat on the same day, shows a cross-section—how the storm would look if it had been sliced near the middle and viewed from the side. The blue line is the north-to-south track that CloudSat flew over Florence. Note that the MODIS image has been rotated.
The CloudSat pass offers a unique view of Florence's asymmetrical structure, the intense convection and rainfall churning inside the storm, and the complex vertical cloud structure that is not visible from above. The storm's clouds reached an altitude of about 15 kilometers (9 miles) at their highest point—fairly high for a tropical cyclone.
The darkest blues represent areas where clouds and raindrops reflected the strongest signal back to the satellite radar. These areas had the heaviest precipitation and the largest water droplets. The blue horizontal line across the data is the melting level; ice particles were present above it, raindrops below it. Note how the radar detects more signal immediately below this line. "It almost looks like two images were pasted together and not matched very well," said Philip Partain, a researcher at Colorado State University who helped design CloudSat's data processing system. "That's because falling ice crystals become coated in water as they pass the melting level and become very reflective to the radar."
View the full resolution image.
Credit: NASA\Colorado State University\Adam Voiland.