THIRN4IMCH67 is the Nimbus-4 Temperature-Humidity Infrared Radiometer (THIR) data product consisting of daily montages of brightness temperatures measured at 6.7 microns on 70 mm photofacsimile film strips. Daytime and nighttime orbital swaths are displayed in strips, each corresponding to a distance approximately from pole to pole and a width from horizon to horizon. The ground resolution of 22.6 km at nadir decreases as the horizontal distance from the subsatellite track increases. Each film strip is gridded with geographic coordinates and is identified by orbit number, time, and an indication of whether it is daytime (D) or nighttime (N). The images are saved as JPEG 2000 digital files. About 1 week of images are archived into a TAR file. Additional information can be found in section 3.4.1 of "The Nimbus IV User's Guide". The THIR instrument was designed to detect emitted thermal radiation in both the 10.5- to 12.5-micrometer region (IR window) and the 6.5- to 7.0-micrometer region (water vapor). The window channel measured cloudtop temperatures day and night. The other channel operated primarily at night to map the water vapor distribution in the upper troposphere and stratosphere. The THIR experiment made measurements from April 18, 1970 until April 8, 1971. This product was previously available from the NSSDC with the identifier ESAD-00194 (old ID 70-025A-02B).