Seasonal hydrography of Ameralik: a southwest Greenland fjord impacted by a land‐terminating glacier
Stuart-Lee, A.E.; Mortensen, J.; van der Kaaden, A.-S.; Meire, L. (2021). Seasonal hydrography of Ameralik: a southwest Greenland fjord impacted by a land‐terminating glacier. JGR: Oceans 126(12): e2021JC017552. https://dx.doi.org/10.1029/2021jc017552Additional data: In: Journal of Geophysical Research-Oceans. AMER GEOPHYSICAL UNION: Washington. ISSN 2169-9275; e-ISSN 2169-9291, more |   |
| Authors | | Top | - Stuart-Lee, A.E., more
- Mortensen, J.
- van der Kaaden, A.-S.
- Meire, L., more
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| Abstract | Greenland’s coastal zone encompasses a large number of fjords, many of which are impacted by glacial meltwater runoff from land-terminating glaciers. This type of fjord has received limited research attention, yet may represent the future of other fjords currently impacted by marine-terminating glaciers that are retreating. In this study we describe the seasonal hydrography of Ameralik, a fjord on the southwest coast of Greenland impacted by a land-terminating glacier. To complement this analysis we compare our results with observations from the neighbouring Godthåbsfjord, which receives meltwater from both land- and marine-terminating glaciers. We find that the absence of subglacial discharge and glacial ice in Ameralik has a strong impact on the inner fjord density profiles and on circulation. The mean temperature of the upper 50 m layer was lower in Ameralik than Godthåbsfjord in May, but by September was 2◦C higher in Ameralik. Dense coastal inflows occur in the late winter months in Ameralik, flushing the fjord and contributing to the return to a weakly stratified state. During the runoff period the surface waters are subject to estuarine circulation and wind forcing, while at intermediate depths a density gradient between the inner and outer fjord regions produces an intermediate baroclinic circulation, resulting in the exchange of water in this layer and the deepening of isopycnals. During summer a large fraction of the meltwater runoff is retained within the fjord rather than being exported. A substantial export of this summer accumulated freshwater occurs in connection with coastal inflows during winter. |
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