Modeling studies of frontogenesis in the upper and middle troposphere

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:6927952

Konor, C S

This research addresses questions associated with upper-level frontogenesis during the evolution of a mid-latitude disturbance in the framework of three-dimensional primitive-equation model simulations on a [beta]-plane. Simulations are performed using two models based on pressure and isentropic vertical coordinates starting with similar initial conditions in a nearly adiabatic atmosphere. Model performance is evaluated using different spatial resolutions for various initial conditions to select the most realistic upper-level frontogenesis simulation. Dynamical processes involved in upper-level frontogenesis are analyzed separately in selected pressure and isentropic coordinate model simulations. Analyses reveal many similarities as well as differences in the process of simulated frontogenesis and tropopause folding with these models. The isentropic coordinate model produces stronger and very narrow upper-level fronts and deep tropopause foldings compared to the pressure coordinate model. Difficulties resulting from intersection of isentropic surfaces with lower boundary with isentropic coordinate model remain unsolved. Consequently, near the lower boundary, potential vorticity and temperature fields are unrealistic. Therefore, combining isentropic coordinate with a [sigma]-coordinate, which follows the terrain, appears very attractive. However, there are many technical difficulties associated with such a general coordinate system. In this study, a method to design such a hybrid coordinate system is discussed in detail.

• Research Organization: California Univ., Los Angeles, CA (United States)
• OSTI ID: 6927952
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540110*
ATMOSPHERIC CIRCULATION
COMPUTERIZED SIMULATION
EARTH ATMOSPHERE
ISENTROPIC PROCESSES
METEOROLOGY
SIMULATION
TROPOSPHERE
WEATHER