An Evaluation of Northern Hemisphere Merged Cloud Analyses from the United States Air Force Cloud Depiction Forecasting System II
Abstract
Data from the CloudSat cloud profiling radar was used to verify the performance, or operational health, of the United States Air Force s World Wide Merged Cloud Analysis (WWMCA) system to detect clouds. WWMCA performance for 2010 over the Northern Hemisphere was analyzed by (1) cloud event category: Cloudy, Partly Cloudy, Clear; (2) geographic region: (Northern Hemisphere, 0N 50N, 0N 23.5N, 23.5N 35N, 35N-50N, 50N 90N, South China Sea, and Southwest Asia), 3) month; and (4) age of input data used by WWMCA. Overall and cloud category performance were evaluated using 11 performance metrics. Overall, WWMCA properly identified cloud categories 65% of the time, with a detection range of 40% 70% depending on the region. WWMCA performed best (worst) at low (high) latitudes. Decreases in WWMCA accuracy were noted when using input data older than 45 minutes. We confirmed that newer (older) data performed best (worst), with an improvement of nearly 20% when using all data available rather than data older than 3 hours. Annual hemispheric average Heidke skill scores were 0.52 for Cloudy, 0.47 for Clear, and 0.09 for Partly Cloudy conditions. Maximum (minimum) HSS values for all three cloud categories occurred at low (high) latitudes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2013
- Accession Number
- ADA581730
Entities
People
- Chandra M. Pasillas
Organizations
- Naval Postgraduate School