Cloud Mass Meridional Transport (CMMT) Events

Synoptic and Mesoscale Storms in the Southern Ocean and their Impact on the Cryosphere

This project aims to investigate the controlling mechanisms of cryospheric variability in Antarctica and the Southern Ocean. The main goal of the research is to advance the understanding of atmospheric processes responsible for the characteristics of Southern Ocean synoptic and mesoscale cyclones that most influence the evolution of the cryosphere. In particular, the focus will be on the dynamic processes that drive sea ice changes and will better quantify the poleward moisture transport which is critical for the maintenance of the Antarctic mass sheet mass balance

What is a Cloud Mass Meridional Transport Event?

Definition (Staude et al., 2004): An event in which a cloud mass travels from an oceanic region perpendicularly onto the continent, lasting at least 48 consecutive hours.

Guidelines for Counting CMMT Events:

• Clouds must be perpendicular to continent.
• If there is a gap greater than 12 hours, it is counted as two separate events.
• If the event starts in one month and ends in another, it is counted as an event for the starting month.
• A CMMT event is considered “skirting” if it starts transporting clouds in one region and continues to transport clouds while moving around the continent.

Example CMMT event (Video)

May 2009 water vapor composite satellite loop illustrating CMMT events both over West Antarctica and over Enderby Land. Note the continual poleward propagation of the cloud masses, represented through the water vapor channel.

Antarctic Regions: