Strange Clouds Off Chilean Coast has Hexagonal Cell Pattern

A few months ago, NASA satellites noticed an unusual cloud cover off the coast of Chile that resembled a hexagonal grid.

The image of the day for February 3, 2023, according to NASA Earth Observatory, was a photograph of the lovely cloud formations taken in August of last year.

Marine Stratocumulus Clouds

The photograph was captured by NASA's Terra satellite's Moderate Resolution Imaging Spectroradiometer (MODIS), and it depicts these holey clouds, also referred to as organized marine stratocumulus clouds, drifting low over the Pacific Ocean.

Marine stratocumulus clouds typically develop over oceans at lower altitudes, less than a mile above the ground. Only in the subtropics and mid-latitudes do organized marine stratocumulus clouds, like the ones in the image, form. They come in two varieties: open-cell and closed-cell.

Open-cell clouds resemble an empty honeycomb structure with the rim of the cells visible and no cloud inside, in contrast to closed-cell clouds, which appear as though a honeycomb has been stuffed with clouds.

Strange Clouds in Hexagonal Cell Pattern

Marine stratocumulus clouds, which cover an average of 23% of the world's oceans and roughly 15% of the planet's surface, are actually quite common, NASA Earth Observatory reported.

The cells were too big to be properly detected from the ground, so scientists were unaware of their existence until the first-ever weather satellites were launched. In February 1961, the open-cell clouds were first caught on film.

Rayleigh-Bénard cells, which are naturally-formed hexagonal cells that occur when fluids are heated from below, are the shape of organized marine stratocumulus clouds. Warm air rising and expanding over the ocean cools and forms clouds.

In closed-cell clouds, the warm air rises in the center and the cool air sinks at the edges, in contrast to open-cell clouds where the warm air goes up along the rim of the cells and sinks through the middle. Each cell could reach a maximum width of 45 miles.

Rayleigh-Bénard Convection

Ilan Koren from the Environmental Sciences and Energy Research Department of the Weizmann Institute explained in 2011 that boiling water exhibits a similar phenomenon to these cloud cells, with the water rising and falling in columns as a result of the temperature difference between the heated base of the pot and its upper surface. Rayleigh-Bénard convection, also referred to as this rolling, cell-like pattern, was first described more than a century ago.

These clouds tend to form more frequently along the western boundaries of continents. In addition, ocean temperatures are lower compared to other regions at the same latitude because the atmosphere is more stable near land masses like continents.

Open Cells vs. Closed Cells

The lovely honeycomb-like clouds don't last for very long because open-cell clouds break up much more quickly than closed-cell clouds, which can maintain their shape for up to 10 hours. Open-cell clouds produce more rainfall than closed-cell clouds.

Additionally, one type of cloud cell can change into another as a result of atmospheric pollution such as smoke, dust, and ship exhaust aerosols.

Cross-hatch-shaped clouds following ship tracks off the western coast of Peru are formed by low marine clouds, according to research published in October 2012 by Pacific Northwest National Laboratory. The tracks are a result of water being drawn in by a large number of pollution particles from ship exhaust, which causes very bright and reflective droplets to form in the clouds.

The image taken by NASA of these peculiar clouds over the Pacific waters in 2022 depicts a larger cell system than is typically observed. Rain or other atmospheric variations, as well as atmospheric instability, could be the reason for this occurrence, Newsweek reports.