Airborne and Ground Based Measurement of the Vertical Structure of Cloud Properties
J. Vanderlei
Martins, JCET/UMBC - NASA GSFC and IFUSP, martins@climate.gsfc.nasa.gov
(Presenting)
Yoram
J.
Kaufman, NASA GSFC, kaufman@climate.gsfc.nasa.gov
Paulo
Artaxo, USP, artaxo@if.usp.br
Lorraine
A.
Remer, NASA GSFC, remer@climate.gsfc.nasa.gov
Daniel
Rosenfeld, The Hebrew Univeristy of Jerusalem, daniel@vms.huji.ac.il
Ilan
Koren, NRC-NASA GSFC, ilank@atmos.gsfc.nasa.gov
A new technique for measuring the microphysical properties of cloud droplets was applied by the first time during the SMOCC experiment in Amazonia. A scanning spectrometer system covering wavelengths from 350 to 2500nm was used onboard the INPE Bandeirante aircraft, in parallel with in situ measurement of aerosol microphysical and chemical properties. The system was used to scan clouds from their illuminated side providing profile information of the cloud spectral reflectance. The spectral reflectance is later converted to cloud thermodynamic and microphysical properties. The simplest product of this data is the vertical separation between water and ice droplets. The difference in refractive indices of water and ice in this spectral range is enough for a very significant separation between both phases. A more complex inversion was also applied to the spectral reflectance data in order to provide measurements of the cloud droplet size. Estimates of the droplet size as a function of the cloud vertical structure shows important characteristics of the growing mechanism of the droplets. This vertical structure can be readily associated with the effect of aerosols particles on cloud droplets and precipitation processes. Results from aircraft measurements during the SMOCC campaign in Amazonia and ground based measurements from Mount Evans in Colorado, US, will be discussed and compared.
Submetido por Jose Vanderlei Martins em 25-MAR-2004