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Assessing the Tangent Linear Behaviour of Common Tracer Transport Schemes and Their Use in a Linearised Atmospheric General Circulation ModelThe linearity of a selection of common advection schemes is tested and examined with a view to their use in the tangent linear and adjoint versions of an atmospheric general circulation model. The schemes are tested within a simple offline one-dimensional periodic domain as well as using a simplified and complete configuration of the linearised version of NASA's Goddard Earth Observing System version 5 (GEOS-5). All schemes which prevent the development of negative values and preserve the shape of the solution are confirmed to have nonlinear behaviour. The piecewise parabolic method (PPM) with certain flux limiters, including that used by default in GEOS-5, is found to support linear growth near the shocks. This property can cause the rapid development of unrealistically large perturbations within the tangent linear and adjoint models. It is shown that these schemes with flux limiters should not be used within the linearised version of a transport scheme. The results from tests using GEOS-5 show that the current default scheme (a version of PPM) is not suitable for the tangent linear and adjoint model, and that using a linear third-order scheme for the linearised model produces better behaviour. Using the third-order scheme for the linearised model improves the correlations between the linear and non-linear perturbation trajectories for cloud liquid water and cloud liquid ice in GEOS-5.
Document ID
20160000946
Document Type
Reprint (Version printed in journal)
Authors
Holdaway, Daniel (Universities Space Research Association Greenbelt, MD, United States)
Kent, James (University of South Wales United Kingdom)
Date Acquired
January 19, 2016
Publication Date
September 14, 2015
Publication Information
Publication: Tellus Series A: Dynamic Meteorology and Oceanography
Volume: 67
Subject Category
Earth Resources and Remote Sensing
Meteorology and Climatology
Report/Patent Number
GSFC-E-DAA-TN28761
Funding Number(s)
CONTRACT_GRANT: NNG11HP16A
Distribution Limits
Public
Copyright
Other
Keywords
Tangent Linear Model
Adjoint
Meteorology