Search
CSV
RISSquare Root and Perturbed Observation Ensemble Generation Techniques in Kalman and Quadratic Ensemble Filtering Algorithms
Publisher: American Meteorological Society
Abstract: he main goal of this work is to present a new square root ensemble generation technique that is consistent with a recently developed extension of Kalman-based linear regression algorithms such that they may perform nonlinear ...
Hindcasting the January 2009 Arctic Sudden Stratospheric Warming with Unified Parameterization of Orographic Drag in NOGAPS. Part II: Short-Range Data-Assimilated Forecast and the Impacts of Calibrated Radiance Bias Correction
Publisher: American Meteorological Society
Abstract: his study is Part II of the effort to improve the forecasting of sudden stratospheric warming (SSW) events by using a version of the Navy Operational Global Atmospheric Prediction System (NOGAPS) that covers the full ...
Long-Period Tidal Forcing of Indian Monsoon Rainfall: An Hypothesis
Publisher: American Meteorological Society
Abstract: This paper examines the nature of the periodic components observed in the interannual variability of June rainfall in northern India by using an eigenvector analysis of the spectra of the June rainfall record (1895?1975) ...
Vertical Covariance Localization for Satellite Radiances in Ensemble Kalman Filters
Publisher: American Meteorological Society
Abstract: A widely used observation space covariance localization method is shown to adversely affect satellite radiance assimilation in ensemble Kalman filters (EnKFs) when compared to model space covariance localization. The two ...
Isolation of the Gravity-Inertial Motion Component in a Nonlinear Atmospheric Model
Publisher: American Meteorological Society
Abstract: Diagnostic methods me considered for isolating gravity-inertial motions in the output of a nonlinear atmospheric numerical model. The gravity-inertial component is defined by the nongeostrophic motions not directly ...
Observation-Dependent Posterior Inflation for the Ensemble Kalman Filter
Publisher: American Meteorological Society
Abstract: nsemble-based Kalman filter (EBKF) algorithms are known to produce posterior ensembles whose variance is incorrect for a variety of reasons (e.g., nonlinearity and sampling error). It is shown here that the presence of ...
Reduction of Middle-Atmospheric Forecast Bias through Improvement in Satellite Radiance Quality Control
Publisher: American Meteorological Society
Abstract: This article discusses a practical problem faced in operational atmospheric forecasting and data assimilation, and efforts to improve forecast quality through the choice of quality control parameters. The need to utilize ...
Accounting for Correlated Observation Error in a Dual-Formulation 4D Variational Data Assimilation System
Publisher: American Meteorological Society
Abstract: ppropriate specification of the error statistics for both observational data and short-term forecasts is necessary to produce an optimal analysis. Observation error stems from instrument error, forward model error, and ...
Untitled
Publisher: American Meteorological Society
Abstract: AbstractIt is well known that the ensemble-based variants of the Kalman filter may be thought of as producing a state estimate that is consistent with linear regression. Here, it is shown how quadratic polynomial regression ...