Author : Kenneth E. Mitchell,Douglas C. Hahn
Publisher : Unknown
Page : 166 pages
File Size : 51,5 Mb
Release : 1989
Category : Cloud forecasting
ISBN : UOM:39015095331750
Development of a Cloud Forecast Scheme for the GL Baseline Global Spectral Model by Kenneth E. Mitchell,Douglas C. Hahn Pdf
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 Central's (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.
