On the onset of entrainment instability over the ocean

✍ Scribed by David P. Rogers

• Book ID: 104630430
• Publisher: Springer
• Year: 1986
• Tongue: English
• Weight: 893 KB
• Volume: 37
• Category: Article
• ISSN: 0006-8314
• DOI: 10.1007/bf00122762

✦ Synopsis

The marine atmospheric boundary layer is characterized by cool temperatures and high humidity. Clouds are observed over most of the oceans. It is generally accepted that these overcast cloud decks break up into scattered fragments due to cloud-top entrainment instability. That is, if the air above the boundary layer is sufficiently cool and dry relative to cloud top, the buoyancy flux will be directed upwards and entrainment can occur freely.

A boundary-layer model is used to test the sensitivity of the model atmosphere to the various processes which promote the onset of cloud-top entrainment instability. It is found that the transition from a solid cloud deck to scattered cumulus clouds depends on a rate process. The cloud cover is sensitive to mesoscale variations in sea surface temperature only if the cloud-top inversion is sufficiently weak.

Boundary-Layer Meteorology 31(1986) 167-182.