Assimilating Surface Data to Improve the Accuracy of Atmospheric Boundary Layer Simulations
- 1 November 2001
- journal article
- Published by American Meteorological Society in Journal of Applied Meteorology and Climatology
- Vol. 40 (11), 2068-2082
- https://doi.org/10.1175/1520-0450(2001)040<2068:asdtit>2.0.co;2
Abstract
Large errors in atmospheric boundary layer (ABL) simulations can be caused by inaccuracies in the specification of surface characteristics in addition to assumptions and simplifications made in boundary layer formulations or other model deficiencies. For certain applications, such as air quality studies, these errors can have significant effects. To reduce such errors, a continuous surface data assimilation technique is developed. In this technique, surface-layer temperature and water vapor mixing ratio are directly assimilated by using the analyzed surface data. Then, the difference between the observations and model results is used to calculate adjustments to the surface fluxes of sensible and latent heat. These adjustments are then used to calculate a new estimate of the ground temperature, thereby affecting the simulated surface fluxes on the subsequent time step. This indirect data assimilation is applied simultaneously with the direct assimilation of surface data in the model's lowest layer, thereby maintaining greater consistency between the ground temperature and the surface-layer mass-field variables. A one-dimensional model was used to study the improvements that result from applying this technique for ABL simulations in two cases. It was found that application of the new technique led to significant reductions in ABL modeling errors.Keywords
This publication has 26 references indexed in Scilit:
- Coupling an Advanced Land Surface–Hydrology Model with the Penn State–NCAR MM5 Modeling System. Part I: Model Implementation and SensitivityMonthly Weather Review, 2001
- Comparing Different Cloud Schemes of a Single Column Model by Using Mesoscale Forcing and Nudging TechniqueJournal of Climate, 1999
- Effects of atmospheric boundary layer mixing representations on vertical distribution of passive and reactive tracersArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 1998
- Impact of Atmospheric Surface-layer Parameterizations in the new Land-surface Scheme of the NCEP Mesoscale Eta ModelBoundary-Layer Meteorology, 1997
- UNCERTAINTY IN THE SPECIFICATION OF SURFACE CHARACTERISTICS: A STUDY OF PREDICTION ERRORS IN THE BOUNDARY LAYERBoundary-Layer Meteorology, 1997
- Simulation of Atmospheric Boundary Layer Processes Using Local- and Nonlocal-Closure SchemesJournal of Applied Meteorology and Climatology, 1997
- Modeling of land surface evaporation by four schemes and comparison with FIFE observationsJournal of Geophysical Research: Solid Earth, 1996
- Sequential Assimilation of Soil Moisture from Atmospheric Low-Level Parameters. Part I: Sensitivity and Calibration StudiesJournal of Applied Meteorology and Climatology, 1993
- Analysis of Urban-Rural Canopy Using a Surface Heat Flux/Temperature ModelJournal of Applied Meteorology, 1978
- The Dependence of Bare Soil Albedo on Soil Water ContentJournal of Applied Meteorology, 1975