Low-pressure system near Iceland coasts.
auteur: Nasa/GSFC/Modis/Novapix
référence: t-nua01-00400
Image Size 300 DPI: 51 * 44 cm
A beautifully-formed low-pressure system swirls off the southeastern coast of Greenland, illustrating the maxim that `nature abhors a vacuum.` The vacuum in this case would be a region of low atmospheric pressure. In order to fill this void, air from a nearby high-pressure system moves in, in this case bringing clouds along for the ride. And because this low-pressure system occurred in the Northern Hemisphere, the winds spun in toward the center of the low-pressure system in a counter-clockwise direction; a phenomenon known as the Coriolis force (in the Southern Hemisphere, the Coriolis force would be manifested in a clockwise direction of movement). The clouds in the image resembled pulled cotton and lace as they spun in a lazy hurricane-like pattern. This huge system swirled over the Denmark Strait in between Greenland and Iceland. The image was taken by the Aqua MODIS instrument on September 4, 2003.