Premium
Gradient Richardson number profiles and changes within an intense mid‐tropospheric baroclinic zone
Author(s) -
Bosart L. F.,
Garcia O.
Publication year - 1974
Publication title -
quarterly journal of the royal meteorological society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.744
H-Index - 143
eISSN - 1477-870X
pISSN - 0035-9009
DOI - 10.1002/qj.49710042608
Subject(s) - baroclinity , radiosonde , richardson number , climatology , geology , atmospheric sciences , troposphere , meteorology , physics , turbulence
Abstract The three‐dimensional pattern of Richardson numbers in isentropic co‐ordinates is investigated for a case study of a mid‐tropospheric baroclinic zone for which special three‐hourly radiosonde data are available. Results show that the lowest Richardson number values are found within the baroclinic zone with most values between 0.25 and 1.0. An equation developed by Roach (1970) was used to relate observed versus computed changes of d/dt (In Ri ) in isentropic co‐ordinates throughout the baroclinic zone. In general stretching deformation contributed to an increase of In Ri in downstream regions of the baroclinic zone whereas the converse was true for shearing deformation in mid‐ and upstream regions of the baroclinic zone. Overall agreement between computed and observed changes ranged from poor outside the baroclinic zone to fair to good within the zone. Air parcels entering the upstream region of the baroclinic zone underwent both frontogenesis and decrease in In Ri . The reverse was noted in the downstream region of the baroclinic zone.