SCRN4L1RAD is the Nimbus-4 Selective Chopper Radiometer (SCR) Level 1 Calibrated Radiances data product. The calibrated radiances are measured at 6 channels from 2.3 to 15 micrometers with a ground resolution of 25 km, and are "declouded" (interpolated and smoothed across regions of cloud). The radiances were used to obtain the temperatures of six successive 10-km layers of the atmosphere from earth or cloudtop level to 60-km height. The data were recovered from the original 9-track tapes, and are now stored online as daily files in their original proprietary binary format with about 14 orbits per day. Spatial coverage is near global from latitude -80 to +80 degrees. The data are available from 27 July 1970 (day of year 208) to 20 February 1973 (day of year 51). The channel 1 temperature monitoring system failed on June 15, 1970, thereby reducing the accuracy of the SCR data. Channels 3 and 4 became noisy and unusable on April 18, 1972. The principal investigator for the SCR experiment was Dr. John T. Houghton from Oxford University. This product was previously available from the NSSDC with the identifier ESAD-00096 (old ID 78-098A-10E).