The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners.
As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i
Variational particle smoothers and their localization
-
2018
-
-
Source: Quarterly Journal of the Royal Meteorological Society, 144(712), 806-825
[PDF-634.68 KB]
Details:
-
Journal Title:Quarterly Journal of the Royal Meteorological Society
-
Personal Author:
-
NOAA Program & Office:
-
Description:Given the success of 4D‐variational methods (4D‐Var) in numerical weather prediction, and recent efforts to merge ensemble Kalman filters with 4D‐Var, we revisit how one can use importance sampling and particle filtering ideas within a 4D‐Var framework. This leads us to variational particle smoothers (varPS) and we study how weight‐localization can prevent the collapse of varPS in high‐dimensional problems. We also discuss the relevance of (localized) weights in near‐Gaussian problems. We test our ideas on the Lorenz'96 model of dimensions n = 40, n = 400, and n = 2,000. In our numerical experiments the localized varPS does not collapse and yields results comparable to ensemble formulations of 4D‐Var, while tuned EnKFs and the local particle filter lead to larger estimation errors. Additional numerical experiments suggest that using localized weights may not yield significant advantages over unweighted or linearized solutions in near‐Gaussian problems.
-
Keywords:
-
Source:Quarterly Journal of the Royal Meteorological Society, 144(712), 806-825
-
DOI:
-
ISSN:0035-9009;1477-870X;
-
Format:
-
Publisher:
-
Document Type:
-
Rights Information:Accepted Manuscript
-
Compliance:Library
-
Main Document Checksum:
-
Download URL:
-
File Type:
