Record Details
Field | Value |
---|---|
Title | A synoptic and radar study of post-cold-frontal squall lines |
Names |
Fosberg, Michael A.
(creator) Decker, Fred W. (advisor) |
Date Issued | 1962-11-30 (iso8601) |
Note | Graduation date: 1963 |
Abstract | Seven cases of post-cold-frontal squall lines moving through the Willamette Valley of Northwest Oregon were investigated by the various techniques of meso-analysis. Time cross sections were converted to space cross sections by using the movement of the radar echo of the squall lines. The observations in time were converted to observations in distance by the time distance relationship of the echo velocity. A percentage technique was used to study the precipitation of the squall lines. Results indicate that the post-cold-frontal squall lines are similar in structure to the pre-frontal squall lines, showing a pressure surge and temperature drop marking the leading edge, a high pressure area immediately behind the leading edge followed by a wide zone of pressure fall. There is evidence that the pressure field is modified by the production of cold air by evaporation of precipitation. No definite features of dew point and relative humidity fields were observed. The precipitation patterns associated with the squall line showed small centers of activity along the squall line with a preference for two zones, one ten miles behind the leading edge and the second from twenty to thirty miles behind the leading edge. An analysis of the radar data showed that the centers of precipitation were recognizable on the PPI and RHI displays. |
Genre | Thesis/Dissertation |
Topic | Meteorology -- Observations |
Identifier | http://hdl.handle.net/1957/49220 |