AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Marine Biological Ice Nuclei – Estimation of Sources and Significance for Marine Clouds
SUSANNAH BURROWS, Corinna Hoose, Ulrich Pöschl, Mark Lawrence, Paul DeMott, Xiaohong Liu, Po-Lun Ma, Phil Rasch, Pacific Northwest National Laboratory
Abstract Number: 550 Working Group: Bioaerosols: Characterization and Environmental Impact
Abstract Particles associated with marine biological activity have been proposed as a possible source of ice nuclei (IN) to the marine boundary layer. Using a combination of satellite data and parameterizations of sea spray emissions, we will argue that the region in which marine biogenic IN are most likely to influence IN concentrations is the remote Southern Ocean, where sea spray emissions and biological activity are strong, and continental aerosols are scarce.
Although concentrations of marine biogenic IN emissions are expected to be small, a large fraction of clouds in the Southern Ocean region contain super-cooled liquid and so these clouds may be particularly sensitive to changes in the concentration of ice nuclei. At the same time, continental aerosol that can act as IN is transported episodically from desert source regions to the remote ocean, often in a well-defined plume that lies above boundary-layer clouds.
To investigate and contrast the sensitivity of marine clouds to ice nuclei and cloud condensation nuclei from local marine sources and remote continental sources, we have performed simulations of marine clouds and their interactions with marine and continental aerosols using a cloud-resolving model. We present preliminary results from these simulations and suggest avenues for further research.