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Author Mahfouf, Jeanfranois ♦ Boilley, Alexandre
Source Directory of Open Access Journals (DOAJ)
Content type Text
Publisher Taylor & Francis Group
File Format HTM / HTML
Date Created 2012-06-15
Copyright Year ©2012
Language English
Subject Domain (in LCC) GC1-1581 ♦ QC851-999
Subject Keyword Anthropology ♦ Low-level wind ♦ Meteorology ♦ Geography ♦ Recreation ♦ Science ♦ Oceanography ♦ Physics ♦ Climatology ♦ Data assimilation ♦ Nudging
Abstract The performance of a new data assimilation algorithm called back and forth nudging (BFN) is evaluated using a high-resolution numerical mesoscale model and simulated wind observations in the boundary layer. This new algorithm, of interest for the assimilation of high-frequency observations provided by ground-based active remote-sensing instruments, is straightforward to implement in a realistic atmospheric model. The convergence towards a steady-state profile can be achieved after five iterations of the BFN algorithm, and the algorithm provides an improved solution with respect to direct nudging. It is shown that the contribution of the nudging term does not dominate over other model physical and dynamical tendencies. Moreover, by running backward integrations with an adiabatic version of the model, the nudging coefficients do not need to be increased in order to stabilise the numerical equations. The ability of BFN to produce model changes upstream from the observations, in a similar way to 4-D-Var assimilation systems, is demonstrated. The capacity of the model to adjust to rapid changes in wind direction with the BFN is a first encouraging step, for example, to improve the detection and prediction of low-level wind shear phenomena through high-resolution mesoscale modelling over airports.
ISSN 02806495
Age Range 18 to 22 years ♦ above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study
Learning Resource Type Article
Publisher Date 2012-06-01
e-ISSN 02806495
Journal Tellus: Series A, Dynamic Meteorology and Oceanography
Volume Number 64
Page Count 15
Starting Page 1
Ending Page 15

Source: Directory of Open Access Journals (DOAJ)