Development and Implementation of an Isentropic Potential Vorticity Algorithm for use at Air Force Global Weather Center

This thesis presents and validates methods for calculating isentropic potential vorticity (IPV) and applies these methods in software programs planned for implementation at the Air Force Global Weather Center (AFGWC). The IPV programs will provide Air Force Weather forecasters additional tools to diagnose atmospheric kinematics and understand atmospheric dynamics. A FORTRAN program is recommended using mandatory-level isobaric data projected to be available on AFGWC computer systems, specifically, from the Navy Operational Global Atmosphere Prediction System and Medium Range Forecast models. Program development and analysis consists of three main steps: (1) data retrieval; (2) IPV calculations; and, (3) interpolation to an isentropic vertical coordinate system. This thesis recommends performing IPV calculations at constant pressure for comparison with other mandatory-level isobaric parameters, or in routine cross-sectional analysis. Additionally, a recommendation is made to calculate IPV at constant potential temperature from interpolated isentropic state variables instead of interpolating isobaric IPV fields. Applications of the developed programs include visualization of synoptic-scale motions an alternative method of locating the tropopause in cross-sectional analysis. This thesis is a significant effort to move toward operational use of isentropic analysis and the incorporation of IPV analysis into forecasting techniques at AFGWC.Air Force Inst of Tech Wright-Patterson AFB OH is the author of 'Development and Implementation of an Isentropic Potential Vorticity Algorithm for use at Air Force Global Weather Center', published 1997 under ISBN 9781423567325 and ISBN 1423567323.