WRF Hindcasts of Cold Front Passages over the ARM Eastern North Atlantic Site: A Sensitivity Study

Journal Article · Wed Aug 01 00:00:00 EDT 2018 · Monthly Weather Review

DOI:https://doi.org/10.1175/MWR-D-17-0281.1· OSTI ID:1460505

Lamraoui, Fayçal ^[1]; Booth, James F. ^[1]; Naud, Catherine M. ^[2]

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1. City College of the City University of New York, New York, New York
2. Applied Physics and Applied Mathematics, Columbia University, and NASA Goddard Institute for Space Studies, New York, New York

The present study explores the ability of the Weather Research and Forecasting (WRF) Model to accurately reproduce the passage of extratropical cold fronts at the DOE ARM eastern North Atlantic (ENA) observation site on the Azores. An analysis of three case studies is performed in which the impact of the WRF domain size, position of the model boundary relative to the ENA site, grid spacing, and spectral nudging conditions are explored. The results from these case studies indicate that model biases in the timing and duration of cold front passages change with the distance between the model domain boundary and the ENA site. For these three cases, if the western model boundary is farther than 1500 km from the site, the front becomes too meridional and fails to reach the site, making 1000 or 1500 km the optimal distances. In contrast, integrations with small distances (e.g., 500 km) between the site and domain boundaries have inadequate spatial spinup (i.e., the domain is too small for the model to properly stabilize). For all three cases, regardless of domain size, the model has biases in its upper-level circulation that impact the position and timing of the front. However, this issue is most serious for 4000-km²domains and larger. For these domains, prolonged spectral nudging can correct cold front biases. As such, this analysis provides a framework to optimize the WRF Model configuration necessary for a realistic hindcast of a cold front passage at a fixed location centered in a domain as large as computationally possible.

• Research Organization: Columbia Univ., New York, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: SC0016344
• OSTI ID: 1460505
• Alternate ID(s): OSTI ID: 1541866; OSTI ID: 1594063
• Journal Information: Monthly Weather Review, Journal Name: Monthly Weather Review Vol. 146 Journal Issue: 8; ISSN 0027-0644
• Publisher: American Meteorological Society
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
meteorology & atmospheric sciences
cold fronts
extratropical cyclones
cold air surges
model evaluation/performance
numerical weather prediction/forecasting
spectral analysis models/distribution
58 GEOSCIENCES
cold front
WRF
Eastern North Atlantic
ARM