Why is it in the news?
- Recently, NASA’s Terra satellite captured a cluster of cavum clouds, also known as hole-punch clouds, over the Gulf of Mexico off Florida’s west coast.
About Cavum Clouds
Top of Form
- Cavum clouds are characterized by their distinctive appearance, resembling a large circle or ellipse that appears to have been precisely cut out from the clouds.
- They leave behind feathery wisps in the middle of the hole, giving them a unique and striking appearance.
- These clouds are also known as hole-punch clouds or fallstreak holes.
Formation:
- Cavum clouds are formed under specific atmospheric conditions.
- When airplanes fly through banks of altocumulus clouds, which are mid-level clouds containing supercooled water droplets, a fascinating process unfolds.
- As the airplane moves through the cloud bank, it triggers a phenomenon known as adiabatic expansion. This process causes the supercooled water droplets to freeze into ice crystals.
- These ice crystals then grow in size and weight, eventually becoming heavy enough to fall out of the sky. This falling ice creates a hole in the cloud layer, thus forming the cavum cloud.
- In the centre of these holes, wispy trails of precipitation can be observed, known as virga, which are the remnants of the falling ice crystals that never reach the ground. Top of Form
| Cloud Type | Description |
| Cirrus Clouds | · High-altitude clouds typically found above 6,000 meters (20,000 feet) with a wispy, curly, or stringy appearance.
· Composed primarily of ice crystals, associated with fair weather. |
| Stratus Clouds | · Horizontal and layered clouds capable of covering the entire sky in a continuous layer.
· Often found close to the Earth’s surface. |
| Cumulus Clouds | · Large, puffy clouds that develop vertically into the atmosphere.
· Formed by strong updrafts of warm, moist air. |
| Nimbostratus Clouds | · Low to middle-level clouds appearing dark grey and often bringing continuous precipitation. |
| Stratocumulus Clouds | · Low clouds characterized by irregular masses and rolling or puffy appearance.
· Typically found below 2,000 meters (6,500 feet). |
| Cumulonimbus Clouds | · Towering clouds with dark bases and tall, billowing towers that extend into the atmosphere.
· Can lead to severe weather phenomena. |
