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Accession Number DE2013-1036558
Title Recent Progress in Nonlinear and Linear Solvers.
Publication Date 2013
Media Count 5p
Personal Author A. G. Salinger C. S. Woodword H. C. Elman K. J. Evans P. A. Lott X. S. Li
Abstract We discuss two approaches for tackling algebraic systems, one is based on block preconditioning and the other is based on multifrontal and hierarchical matrix methods. First we consider a new preconditioner framework for supporting implicit time integration within an atmospheric climate model. We give an overview of the computational infrastructure used in atmospheric climate studies, address specific challenges of weak-scalability of numerical methods used in these codes, outline a strategy for addressing these challenges, and provide details about the software infrastructure being developed to implement these ideas. In the second part, we present our recent results of employing hierarchically semiseparable low-rank structure in a multifrontal factorization framework. This leads to superfast linear solvers for elliptic PDEs and effective preconditioners for a wider class of sparse linear systems. Understanding the sensitivity of Earth's climate to radiative forcing requires ensemble forecasts over long time periods. To resolve local phenomena, such as hurricanes, and measure variability at the decadal scale, high resolution global simulations are needed.
Keywords Algebra
Atmospheric circulation
Climate models
Computer codes
Mathematical models
Partial differential equations(PDEs
Weather forecasting

Source Agency Technical Information Center Oak Ridge Tennessee
NTIS Subject Category 55C - Meteorological Data Collection, Analysis, & Weather Forecast
72B - Algebra, Analysis, Geometry, & Mathematical Logic
Corporate Author Oak Ridge National Lab., TN.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1325
Contract Number DE-AC05-00OR22725

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