HR: 0800h
AN: A51D-0728 [Abstracts]
TI: Preliminary results of the Cloud-Aerosol Interaction Measurements (CLAIM) 2007 campaign on the Amazon Basin, Brazil
AU: * Correia, A L
EM: acorreia@climate.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 613.2, Bldg 33, Rm C309, Greenbelt, MD 20771,
United States
AU: Fernandez-Borda, R
EM: rfborda@climate.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 613.2, Bldg 33, Rm C309, Greenbelt, MD 20771,
United States
AU: Fernandez-Borda, R
EM: rfborda@climate.gsfc.nasa.gov
AF: University of Maryland, Baltimore County JCET, 5523 Research Park Dr, Suite 320,
Baltimore, MD 21250, United States
AU: Martins, J V
EM: martins@climate.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 613.2, Bldg 33, Rm C309, Greenbelt, MD 20771,
United States
AU: Martins, J V
EM: martins@climate.gsfc.nasa.gov
AF: University of Maryland, Baltimore County JCET, 5523 Research Park Dr, Suite 320,
Baltimore, MD 21250, United States
AB:
Clouds and precipitation play an important role on Earth's radiation budget, water and hydrological cycles, as well
as energy cycles through latent heat release in the atmosphere. Under several aspects the interaction between
aerosols and clouds is still a poorly understood process, and one reason for this is the lack of experimental
observations to characterize the evolution of cloud microphysical structure.
An instrumentation suite was put together to assess these issues. The Cloud Scanner is a scanning radiometer
composed of 2 wavelengths in the near infrared (2.10 and 2.25 μm) used for the separation between ice and
water, and 3 wavelengths in the thermal infrared (8, 11 and 12 μm) for the measurement of cloud
brightness temperature, cirrus properties and water vapor correction. The Rainbow Camera is a multiangle
imaging polarimeter with the wavelengths 0.47, 0.55, 0.66, 0.76, 0.87, and 0.91 μm, with 60 degrees FOV,
used to retrieve droplet effective radii and distribution width. Both instruments were integrated onto a research
aircraft for a field campaign over the Brazilian Amazon Basin from Sep-Oct 2007 under varying conditions of
aerosol loading and cloud type, development stages, and cover area.
The preliminary results obtained include real-time mappings of ice/water separation for clouds, with temperature
profiles allowing for the retrieval of glaciation levels for a variety of cloud developmental stages and aerosol
loadings, including deep convective cumulus clouds and/or high aerosol content. Vertical profiles of effective
radius can be obtained using the measurements in 2.10 μm as entries in a look up table from a 3D radiative
transfer model for the cloud field. The post-processed polarimeter measurements allow retrieving a polarized
reflectance signal from which one can derive effective radii and distribution widths of droplets for clouds in the
observed scenes. These results help understanding and quantifying the effects of cloud-aerosol interactions and
their consequences for cloud microphysics.
DE: 3311 Clouds and aerosols
DE: 3354 Precipitation (1854)
DE: 3359 Radiative processes
DE: 3360 Remote sensing
DE: 9360 South America
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting