May 15, 2022 - "Go!" written by cloud off the coast of Chile
Go
Tweet
Share
In a letter to a friend dated January 14, 1843, Henry David Thoreau
wrote, “You must not blame me if I do talk to the clouds…”. People have
long been talking to, gazing at, and imagining seeing things in clouds
as they look upward from Earth. These days, we can study the clouds by
looking down on the from space—and the clouds themselves may sometimes
seem to talk to us.
On May 6, 2022, a full 179 years after Thoreau admitted to cloud
conversations, that the Moderate Resolution Imaging Spectroradiometer
(MODIS) on board NASA’s Aqua satellite acquired a true-color image of a
remarkable configuration of clouds off the coast of Chile, which seemed
to be urging “Go!”. Maybe the clouds were sports fans, or—and much more
likely—cloud and atmospheric conditions created patterns that, when
combined with human imagination, appeared to create a word in the sky,
just waiting to be captured by MODIS.
The Pacific Ocean off the coast of Chile is covered in large banks of
cloud most of the time, and the region is famous for the formation of
bizarre patterns. The dark, lacy swirl that forms the “G” is a type of
open-cell cumulus pattern, while the thick white cloud is basically
closed-cell marine stratocumulus. The dark breaks in the white cloud
bank that appear to form the “o” and “!” are simply areas without
cloud, allowing the dark waters of the ocean to show through and are
most likely created by wind patterns.
Back in Thoreau’s day—actually until 1960 when NASA launched the first
weather satellite—no one had noticed that clouds over the ocean
frequently appeared to be formed in hexagonal cells with diameters
ranging from 50 – 100 km (30-60 miles). These cell patterns are created
by mesoscale cellular convection (MCC). In open cells, air is falling
in the center of the hexagon and rising around the edges, so clouds
formed at the edges, creating a lacy-looking pattern. In closed-cell
clouds, air is rising in the center, so the hexagon is filled with
fluffy cloud. There is also a third type of cloud formed by mesoscale
cellular convection—an intermediate type with a radial structure that
looks something like flowers or a wagon wheel. These are called
actinoform clouds, derived from the Greek word “aktinos”, meaning
“ray”. There are at least 2 actinoform clouds within the lacy
open-celled cloud that makes up the “G”.
Image Facts
Satellite: Aqua
Date Acquired: 5/6/2022
Resolutions: 1km (2.7 MB), 500m (7.6 MB), 250m (5.4 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=2022-05-15
--- up 10 weeks, 6 days, 21 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)