January 16, 2019 - Swirls of ice imitating cloud

Swirls of ice imitating cloud

When seen from space, complex winter scenes that include cloud, snow, and ice may look like a magnificent study in white. Thanks to similar reflectance values, cold and fluffy clouds, brittle and frigid ice, and soft, fluffy snow all appear similar in true-color satellite imagery. While this conveys the power and chill of a winter landscape, scientists frequently want to be able to differentiate these features. To tell the difference between snow, ice, and cloud, scientists often turn to false-color images.

On January 9, 2019, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Terra satellite acquired two views of a wintery scene of the coast of Newfoundland and Labrador, Canada. The true-color version of this image, which can be seen HERE, showed swaths of white on a background of blue ocean. A bank of cloud in the northwest appeared to sweep into dramatic swirls over the water. The swirling patterns were unusual, especially for cloud.

In this false-color image, which is created by using both infrared and visible light (true-color uses visible light only), the differences between ice, cloud, and snow are readily apparent. Ice appears mid-range blue, vegetation appears green, snow appears bright turquoise, water appears black, and cloud appears white or, in some areas, very light pink. With this combination the swirls are easily recognized as ice which has been swirled into eddies by the off-shore currents.

Image Facts
Satellite: Terra
Date Acquired: 1/9/2019
Resolutions: 1km (913.4 KB), 500m (2.4 MB), 250m (2.1 MB)
Bands Used: 7,2,1
Image Credit: MODIS Land Rapid Response Team, NASA GSFC