Editorial Type:
Article
Article Type:
Research Article

Effects of Varying the Shape of the Convective Heating Profile on Convectively Coupled Gravity Waves and Moisture Modes

Željka Fuchs Physics Department, Faculty of Science, University of Split, Split, Croatia, and Physics Department and Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, New Mexico

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Saska Gjorgjievska Physics Department and Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, New Mexico

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David J. Raymond Physics Department and Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, New Mexico

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Print Publication:
01 Aug 2012
DOI:
https://doi.org/10.1175/JAS-D-11-0308.1
Page(s):
2505–2519
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Abstract

The analytical model of convectively coupled gravity waves and moisture modes of Raymond and Fuchs is extended to the case of top-heavy and bottom-heavy convective heating profiles. Top-heavy heating profiles favor gravity waves, while bottom-heavy profiles support moisture modes. The latter behavior results from the sensitivity of moisture modes to the gross moist stability, which is more negative with bottom-heavy heating.

A numerical implementation of the analytical model allows calculations in the two-dimensional nonrotating case as well as on a three-dimensional equatorial beta plane. In the two-dimensional case the analytical and numerical models are mostly in agreement, although minor discrepancies occur. In three dimensions the gravity modes become equatorial Kelvin waves whereas the moisture modes are more complex and require further investigation.

Corresponding author address: Željka Fuchs, Physics Department and Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, NM 87801. E-mail: zeljka@kestrel.nmt.edu

Abstract

The analytical model of convectively coupled gravity waves and moisture modes of Raymond and Fuchs is extended to the case of top-heavy and bottom-heavy convective heating profiles. Top-heavy heating profiles favor gravity waves, while bottom-heavy profiles support moisture modes. The latter behavior results from the sensitivity of moisture modes to the gross moist stability, which is more negative with bottom-heavy heating.

A numerical implementation of the analytical model allows calculations in the two-dimensional nonrotating case as well as on a three-dimensional equatorial beta plane. In the two-dimensional case the analytical and numerical models are mostly in agreement, although minor discrepancies occur. In three dimensions the gravity modes become equatorial Kelvin waves whereas the moisture modes are more complex and require further investigation.

Corresponding author address: Željka Fuchs, Physics Department and Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, NM 87801. E-mail: zeljka@kestrel.nmt.edu
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