Accession Number:

ADA056959

Title:

Persistence, Runs, and Recurrence of Visibility.

Descriptive Note:

Environmental research papers,

Corporate Author:

AIR FORCE GEOPHYSICS LAB HANSCOM AFB MASS

Personal Author(s):

• Lund,Iver A.
• Grantham,Donald D.

Report Date:

1978-01-31

Pagination or Media Count:

47.0

Abstract:

A total of 511,056 hourly observations of visibility, taken over a 13-year period at nine stations, was studied to obtain a better understanding of the characteristics of persistence, runs, and recurrence. Each hourly visibility observation was categorized as either greater than or equal to 10 miles, greater than or equal to 5 miles, less than or equal to 3 miles, less than or equal to 1 mile in summer, or less than or equal to 0.25 mile in winter. Probabilities of each category were estimated from relative frequencies determined from this large data sample and were compared with some theoretical models. The models can be applied to estimate the probability that any visibility category will be observed for sequences of x hours, or more for exactly x hours or at time t, and also at time tx hours. Author

Descriptors:

• *WEATHER FORECASTING
• DATA PROCESSING
• TIME INTERVALS
• OBSERVATION
• METEOROLOGICAL DATA
• SEASONAL VARIATIONS
• VISIBILITY
• DATA ACQUISITION
• STATISTICAL ANALYSIS
• WEATHER STATIONS
• METEOROLOGICAL CHARTS

Subject Categories:

• Meteorology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE