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Non‐hydrostatic simulations of a cold front observed during the Fronts 87 experiment
Author(s) -
Redelsperger J.L.,
Lafore J.P.
Publication year - 1994
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.49712051703
Subject(s) - rainband , baroclinity , cold front , hydrostatic equilibrium , geology , front (military) , momentum (technical analysis) , frontogenesis , meteorology , mechanics , warm front , climatology , physics , mesoscale meteorology , tropical cyclone , finance , quantum mechanics , economics
A two‐dimensional non‐hydrostatic cloud model is used to simulate a frontal system observed on 11 November 1987 during the Fronts 87 experiment. The cloud‐resolving model is able to reproduce a large variety of frontal bands, starting from only the meso‐α‐scale fields produced by a hydrostatic forecast model. A narrow cold‐frontal rainband is identified at the surface cold front. Two classes of wide bands are also simulated: a wide cold‐frontal rainband and warm‐sector wide rainbands. The vertical‐velocity fields exhibit similar banded features in both the simulations and the Doppler‐radar observations, with bands having the same position, intensity and width. Several sensitivity experiments are presented. One of them shows that the initial knowledge of the ageostrophic circulation is not necessary to give a successful simulation. Other experiments show that the along‐front baroclinicity drives the wide‐band formation whereas the along‐front deformation is not important. The heat, moisture and horizontal momentum budgets are also investigated, in order to determine the rainband effects on larger scales.