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This content will become publicly available on November 16, 2025

Title: Convective and Orographic Origins of the Mesoscale Kinetic Energy Spectrum
Abstract The mesoscale spectrum describes the distribution of kinetic energy in the Earth's atmosphere between length scales of 10 and 400 km. Since the first observations, the origins of this spectrum have been controversial. At synoptic scales, the spectrum follows a −3 spectral slope, consistent with two‐dimensional turbulence theory, but a shallower −5/3 slope was observed at the shorter mesoscales. The cause of the shallower slope remains obscure, illustrating our lack of understanding. Through a novel coarse‐graining methodology, we are able to present a spatio‐temporal climatology of the spectral slope. We find convection and orography have a shallowing effect and can quantify this using “conditioned spectra.” These are typical spectra for a meteorological condition, obtained by aggregating spectra where the condition holds. This allows the investigation of new relationships, such as that between energy flux and spectral slope. Potential future applications of our methodology include predictability research and model validation.  more » « less
Award ID(s):
2123496 2206380
PAR ID:
10596381
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Geophysical Research Letters
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
21
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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