Accession Number:

ADA231595

Title:

Development of a Cloud Forecast Scheme for the GL Baseline Global Spectral Model

Descriptive Note:

Final rept. 1 Oct 1987-30 Sep 1989,

Corporate Author:

AIR FORCE SYSTEMS COMMAND HANSCOM AFB MA GEOPHYSICS LAB

Report Date:

1989-12-20

Pagination or Media Count:

163.0

Abstract:

Using forecast relative humidity RH from a global model, several pre-existing diagnostic RH-to-cloud schemes were tested to forecast global fractional cloud cover in a postprocessor format. Since none of the schemes tested provided a superior cloud forecast when compared to Air Force Global Weather Centrals AFGWC operational 5LAYER cloud forecasts, a new RH-to-cloud scheme was developed by relating cumulative frequencies of forecast RH to cumulative frequencies of analyzed cloud cover from the AFGWC RTNEPH cloud analysis. This scheme creates a series of forecast time dependent RH-to-cloud curves that can be temporally updated to account for changes in season, cloud analysis, or forecast model, The global model used was a spectral-type developed by the Geophysics Laboratory GL using parameterized diabatic physics presently incorporated in the operational GSM global spectral model at AFGWC.

Subject Categories:

  • Meteorology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE