Loading…

The Efficiency of Data Assimilation

Data assimilation is the application of Bayes' theorem to condition the states of a dynamical systems model on observations. Any real‐world application of Bayes' theorem is approximate, and therefore, we cannot expect that data assimilation will preserve all of the information available fr...

Full description

Saved in:
Bibliographic Details
Published in:Water resources research 2018-09, Vol.54 (9), p.6374-6392
Main Authors: Nearing, Grey, Yatheendradas, Soni, Crow, Wade, Zhan, Xiwu, Liu, Jicheng, Chen, Fan
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Data assimilation is the application of Bayes' theorem to condition the states of a dynamical systems model on observations. Any real‐world application of Bayes' theorem is approximate, and therefore, we cannot expect that data assimilation will preserve all of the information available from models and observations. We outline a framework for measuring information in models, observations, and evaluation data in a way that allows us to quantify information loss during (necessarily imperfect) data assimilation. This facilitates quantitative analysis of trade‐offs between improving (usually expensive) remote sensing observing systems versus improving data assimilation design and implementation. We demonstrate this methodology on a previously published application of the ensemble Kalman filter used to assimilate remote sensing soil moisture retrievals from Advanced Microwave Scattering Radiometer for Earth (AMSR‐E) into the Noah land surface model. Key Points Define efficiency of data assimilation from an information theory perspective Measures the total information available to data assimilation versus the amount extracted by an (imperfect) parametric DA algorithm Application example is an application of the EnKF to soil moisture assimilation
ISSN:0043-1397
1944-7973
DOI:10.1029/2017WR020991