• MODIS Pic of the Day 21 May 2022

    From Dan Richter@1:317/3 to All on Sat May 21 12:00:08 2022
    May 21, 2022 - Saharan Dust approaching South America

    Saharan Dust approaching South America
    Tweet
    Share

    On May 19, 2022, a cloud of dust from Africa’s Sahara Desert was
    captured approaching northeastern South America by the Moderate
    Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Aqua
    satellite. The leading edge of a thick pulse of tan dust, which appears
    to be mixed in with the white clouds, can be seen to the east (right)
    in this image, sitting about 860 miles (1,85 km) off the coast of
    Venezuela and heading southwest. A thinner veil of dust has already
    crossed the Atlantic Ocean to move over the Lesser Antilles, Venezuela,
    Guyana, Suriname, and French Guiana.

    A wide silvery-tan band that crosses the image from north to south is
    actually caused by an optical phenomenon known as “sunglint”. This
    occurs when sunlight reflects off the surface of water at the same
    angle that a satellite sensor views it. The result is a mirror-like
    reflection of sunlight off water and back at the sensor, creating a
    silver streak in an image. While the quantity of dust suspended in the
    atmosphere in the streak of sunglint is the same as the area
    surrounding it, the streak appears darker due to the sunglint.

    The dust seen in this image is just the leading edge of a long train of
    dust created by repetitive pulses of dust that have blown off of
    Western Africa from May 12 through May 19. By May 17, the Trinidad and
    Tobago Weather Center warned that a “significant and high”
    concentration of dust was set to move across the Lesser Antilles on May
    18 – 20, and elevated Saharan Dust levels are expected to remain across
    that country until May 27. Over the next several days the dust is
    expected to move northward over the Gulf of Mexico to impact the Gulf
    Coast of the United States, including parts of Texas and most of
    Florida, with impacts the heaviest on or around May 24.

    Image Facts
    Satellite: Aqua
    Date Acquired: 5/19/2022
    Resolutions: 1km (2.7 MB), 500m (7.8 MB), 250m (5.8 MB)
    Bands Used: 1,4,3
    Image Credit: MODIS Land Rapid Response Team, NASA GSFC



    https://modis.gsfc.nasa.gov/gallery/individual.php?db_date=2022-05-21

    --- up 11 weeks, 5 days, 20 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)