Inner-Loop Stopping Criteria for Incremental Four-Dimensional Variational Data Assimilation
نویسندگان
چکیده
منابع مشابه
Four-Dimensional Data Assimilation
Surface inhomogeneities, including boundaries between different types of vegetations and land use patterns, have important effects on the structure of the atmospheric boundary layer. Changes in the surface roughness, temperature and wetness make the planetary boundary layer (PBL) nonhomogeneous and produce substantial horizontal gradients of boundary layer properties. Significant differences in...
متن کاملDownscaling of radio brightness measurements for soil moisture estimation: A four-dimensional variational data assimilation approach
This paper investigates the feasibility of estimating large-scale soil moisture profiles and related land surface variables from 1.4 GHz (L-band) passive microwave measurements, using variational data assimilation. Our four-dimensional assimilation algorithm takes into account both model and measurement uncertainties and provides dynamically consistent interpolation and extrapolation of remote ...
متن کاملExistence and Uniqueness for Four-Dimensional Variational Data Assimilation in Discrete Time
Variational techniques for data assimilation, i.e., estimating orbits of dynamical models from observations, are revisited. It is shown that under mild hypotheses a solution to this variational problem exists. Using ideas from optimal control theory, the problem of uniqueness is investigated and a number of results (well known from optimal control) are established in the present context. The va...
متن کاملA penalized four-dimensional variational data assimilation method for reducing forecast error related to adaptive observations
Four-dimensional variational (4D-Var) data assimilation method is used to find the optimal initial conditions by minimizing a cost function in which background information and observations are provided as the input of the cost function. The optimized initial conditions based on background error covariance matrix and observations improve the forecast. The targeted observations determined by usin...
متن کاملPOD/DEIM reduced-order strategies for efficient four dimensional variational data assimilation
This work studies reduced order modeling (ROM) approaches to speed up the solution of variational data assimilation problems with large scale nonlinear dynamical models. It is shown that a key ingredient for a successful reduced order solution to inverse problems is the consistency of the reduced order Karush-KuhnTucker conditions with respect to the full optimality conditions. In particular, a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Weather Review
سال: 2006
ISSN: 1520-0493,0027-0644
DOI: 10.1175/mwr3242.1