Articles | Volume 22, issue 3
https://doi.org/10.5194/os-22-1861-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-22-1861-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Along-channel variability of Total Exchange Flow in a narrow, well-mixed estuary: influence of the M4 tide
Andalusian Institute for Earth System Research (IISTA), University of Granada, Avda. del Mediterráneo s/n, Edificio CEAMA, Granada 18006, Spain
Hans Burchard
Leibniz Institute for Baltic Sea Research Warnemünde, Physical Oceanography, 18119 Rostock, Seestr. 15, Germany
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The Greenland Ice Sheet is an important contributor to global sea level rise. In northern Greenland, floating glacier tongues are primarily melted by ocean currents. These processes are difficult to observe, so we developed a realistic numerical model to study ocean-driven melting at Greenland's largest floating ice tongue, the 79° North Glacier. Our simulation reveals the details of the oceanic currents bringing warm water toward the ice base, melting and shaping the glacier tongue from below.
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Qing Li, Jorn Bruggeman, Hans Burchard, Knut Klingbeil, Lars Umlauf, and Karsten Bolding
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Different ocean vertical mixing schemes are usually developed in different modeling framework, making the comparison across such schemes difficult. Here, we develop a consistent framework for testing, comparing, and applying different ocean mixing schemes by integrating CVMix into GOTM, which also extends the capability of GOTM towards including the effects of ocean surface waves. A suite of test cases and toolsets for developing and evaluating ocean mixing schemes is also described.
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Short summary
Combining field observations with an analytical tidal scenario, we estimated in the Guadalquivir estuary its Total Exchange Flow (TEF), which has implications for water quality and residence times. The influence of tidal asymmetry on TEF is also explored. Results reveal a spatial variability in TEF and that salinity–current covariance exerts greater control on TEF than tidal asymmetry. The approach is suitable for regional studies evaluating sensitivity to changes in runoff, salinity and tides.
Combining field observations with an analytical tidal scenario, we estimated in the Guadalquivir...