New determinations of tides on the north-western Ross Ice Shelf

• Published in: Antarctic Science
• Main Authors: Ray, Richard D., Larson, Kristine M., Haines, Bruce J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2020
• Subjects: Geology; Ecology, Evolution, Behavior and Systematics; Oceanography; Ross Ice Shelf; Cape Roberts; Scott Base; Antarctic Science; Ice Shelf
• Online Access: http://dx.doi.org/10.1017/s0954102020000498; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102020000498

Abstract New determinations of ocean tides are extracted from high-rate Global Positioning System (GPS) solutions at nine stations sitting on the Ross Ice Shelf. Five are multi-year time series. Three older time series are only 2–3 weeks long. These are not ideal, but they are still useful because they provide the only in situ tide observations in that sector of the ice shelf. The long tide-gauge observations from Scott Base and Cape Roberts are also reanalysed. They allow determination of some previously neglected tidal phenomena in this region, such as third-degree tides, and they provide context for analysis of the shorter datasets. The semidiurnal tides are small at all sites, yet M 2 undergoes a clear seasonal cycle, which was first noted by Sir George Darwin while studying measurements from the Discovery expedition. Darwin saw a much larger modulation than we observe, and we consider possible explanations - instrumental or climatic - for this difference.