Satellite and ship-based estimates of cloud-aerosol interactions during MAGIC campaign
Authors
Patrick Minnis — NASA - Langley Research Center
J.-Y. Christine Chiu — Colorado State University
Christopher Rogers Yost — Science Systems and Applications, Inc.
David Painemal — NASA LaRC /SSAI
Category
Warm Low Clouds and Interactions with Aerosol
Description
The interactions between cloud microphysics and cloud condensation nuclei (CCN) are investigated over the Northeast Pacific with observations from MAGIC campaign during 2012-2013. We analyze the dependency of cloud droplet number concentration (Nd) on CCN, through the metric χ=∂ln(Nd)/∂ln(CCN) by combining remotely sensed cloud properties and surface observations of CCN. Cloud retrievals are derived from satellites instruments (the Fifteenth Geostationary Operational Environmental Satellite Imager: GOES-15, and the MOderate Resolution Spectroradiometer: MODIS) and from a ship-borne Cimel sun-photometer, whereas Nd is calculated assuming cloud adiabaticity. Satellite Nd is highly correlated with CCN (~0.6), with χ reaching values close to the upper physical limit of 1 (χ>0.9). When combining sun-photometer retrievals with a two-channel microwave radiometer liquid water path, the cloud aerosol-interactions metric χ is high and consistent with its satellite counterpart. The importance of the spatial/temporal scale and potential artifacts associated with retrievals biases will be examined. Particular attention will be paid to the role of the boundary layer turbulence in modulating χ, and to the precipitation signature in the remotely sensed retrievals.
