NASA MODIS Image of the Day: March 29, 2012 – Clouds along the Great Australian Bight
An impressive bank of clouds hung over the Great Australian Bight in early fall, 2012, stretching thousands of kilometers from Perth, Western Australia to Adelaide, Southern Australia and beyond. The cloud bank also extended thousands of kilometers to the south, extending beyond the southern edge of this image and over the Indian Ocean. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on March 23, 2012 at 1:45 UTC (12:45 p.m. local time). On that same day, Weatherzone reported that the first strong cold front of the season had surged up from the Southern Ocean, bringing the bitter gale wind to southeast Australia. Although that region is to the east of this image, the clouds seen in the Great Australian Bight are likely part of that same extensive cold front. The cloud formations seen in this image are both beautiful and complex. They appear to be primarily convective clouds, with an uneven cloud surface and readily recognizable independent cellular cloud areas. Convective clouds are formed when warm, humid air rises, such as over water that is warmer than the atmosphere. As air rises, it cools. When humid air is cooled sufficiently, water condenses onto tiny particles suspended in the air, forming droplets, and clouds are formed. A cold front is simply the leading edge of a cooler mass of air. As a large cold front moves over an expanse of warmer waters, conditions can become quite favorable for formation of a large bank of convective clouds.
