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This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.

Cloud Clearing


Given the clear radiance, Rclr and the fraction of clouds, alphai in scene i.

Ri = (1-alphai) · Rclr + alphai · Rcld
Rclr = R1 + eta · ( R1 - R2 )
eta ident alpha1/(alpha2 - alpha1)

Chahine, M.T. 1974, J. Atmos. Sci. 31 p.233

Susskind, J., J. Joiner and C.D. Barnet 1995. Determination of atmospheric and surface parameters from simulated AIRS/AMSU sounding data. I. Retrieval methodology. submitted to J. Atmos. Oceanic Tech. (JAOT) Sep. 1995.

N* method

N* ident alpha1/alpha2 = (R1 - Rclr)/(R2 - Rclr)
Rclr = (R1 - N* R2)/(1 - N*)
eta = N* / (1 - N*)

McMillin, L.M. and C. Dean 1982. Evaluation of a new operational technique for producing clear radiances. J. Appl. Meteor. 21 p.1005-1014.

Smith, W.L. 1968. An improved method for calculating tropospheric temperature and moisture from satellite radiometer measurements. Monthly Weather Review 96 p.387-396.