In October 2007, strong, dry Santa Ana winds raised a major dust plume and several minor plumes on the Baja California peninsula. The light brown dust spread west to the Pacific Ocean (image top right). Because they are warm, dry, and strong, Santa Ana winds reduce soil moisture and famously promote dust storms such as this. On this occasion, the Santa Anas also supported the outbreak of fires in southern California that resulted in significant damage to homes in hilly, wooded country.
Dust plumes are known to start from relatively small, dust-prone areas. Here the plumes rise from the Real del Castillo agricultural valley, which is surrounded by rocky hills in northern Baja California. The valley is 25 miles long, and part of Mexico’s wine-producing region. Specifically, the dust is rising from spreads of loose sediment known as alluvial fans. Small streams from the local hills carry sediment with every rainstorm and deposit it at the foot of small canyons on the east side of the valley. It is notable that the vegetated farmland itself—the small rectangular pattern on the valley floor—protects the soil from the wind and is not producing dust plumes.
Astronaut photograph ISS016-E-5526 was acquired on October 21, 2007, with a Kodak 760C digital camera fitted with a 280 mm lens. The image was taken by the Expedition 16 crew. The image is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Laboratory, Johnson Space Center. The image in this article has been cropped and enhanced to improve contrast. Lens artifacts have been removed. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth.