DATA PROCESSING PROCEDURES IN NUMERICAL MESOANALYSIS

Abstract

Pressure traces taken from microbarograms of first-order and research network stations are prepared for objective analysis on an electronic computer by placing paired numbers of time and pressure on punched cards. Data are evaluated at significant points along the trace in such a way that the trace between recorded points is approximately a straight line. Allowance is made for corrections for slow or fast clock, and deviations between aneroid and mercurial barometric readings are made by the computer. From use of a suitable reference atmosphere, sea level pressures (P* values) are determined for first-order stations from mean station pressures for some 3-hour period for which all recorded pressure traces are relatively undisturbed. P* values for network stations are derived from a map analyzed for first-order stations. The mesoanalysis program then produces a sea level (P*) map for any particular minute in the period of analysis. Several maps produced by the program are compared with mesomaps produced by manual methods, and with the National Weather Analysis Center analysis. A series of maps at 10-minute intervals is shown which indicates the development and history of individual cells of the mesosystems.