Anomaly Nesting: A Methodology to Downscale Seasonal Climate Simulations from AGCMs

In this paper a methodology is proposed to downscale coarse-resolution atmospheric general circulation model (AGCM) seasonal simulations. Anomaly nesting involves replacing the climatology of the driving AGCM with observed (in this case the National Centers for Environmental Prediction reanalysis) c...

Full description

Saved in:
Bibliographic Details
Published in:Journal of climate 2004-09, Vol.17 (17), p.3249-3262
Main Authors: Misra, Vasubandhu, Kanamitsu, Masao
Format: Article
Language:English
Subjects:
Atmospheric circulation
Atmospheric models
Basins
Climate
Climate change
Climate models
Climatic zones
Climatology
Cost of living adjustments
Earth, ocean, space
Exact sciences and technology
External geophysics
General circulation models
Global climate models
Meteorology
Modeling
Nesting
Ocean basins
Oceans
Scientific method
Simulation
Simulations
Weather analysis and prediction
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this paper a methodology is proposed to downscale coarse-resolution atmospheric general circulation model (AGCM) seasonal simulations. Anomaly nesting involves replacing the climatology of the driving AGCM with observed (in this case the National Centers for Environmental Prediction reanalysis) climatology at the lateral boundaries of the nested regional climate model (the regional spectral model). In this study the methodology is tested over South America and the neighboring ocean basins. A comparison of the austral summer seasonal simulation with the conventional way of nesting, namely driving the regional model with full AGCM forcing, reveals that substantial gains in the deterministic skill are realized through anomaly nesting. It is also shown that the high-frequency variance (at 3–30- and 30–40-day time scales) is more realistic from the anomaly nesting procedure.
ISSN:0894-8755
1520-0442
DOI:10.1175/1520-0442(2004)017<3249:anamtd>2.0.co;2