Idealized numerical modeling of thermally driven baroclinic exchange is performed to understand how cross‐shore flow is modulated by steady alongshore currents and associated shear‐generated turbulence. In general, we find that shear‐driven vertical mixing reduces the temperature gradients responsible for establishing the baroclinic flow, such that cross‐shore thermal exchange diminishes with alongshore current speed. Circulation in a base‐case simulation of thermal exchange with no alongshore forcing contains a cooling response consisting of a midday flow in the form of a downslope current with a compensating onshore near‐surface flow driving cross‐shore exchange, followed by an afternoon warming response flow via an offshore‐directed surface warm front, with a compensating return flow at the bottom. Nighttime convective cooling enhances vertical mixing and decelerates the warming response, and the diurnal cycle is renewed. In this base‐case scenario, representative of tropical reef environments with optically clear water and weak alongshore flow, surface heating and cooling can drive cross‐shore circulation with
- PAR ID:
- 10483937
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- Environmental Science & Technology
- Volume:
- 57
- Issue:
- 39
- ISSN:
- 0013-936X
- Page Range / eLocation ID:
- 14674 to 14683
- Subject(s) / Keyword(s):
- nearshore pollution modeling water quality waves
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.est.2c08656
