Computations were performed using the Portland Institute for Computational Science cluster computer, Coeus, acquired with support from NSF award #DMS1624776 and ARO award #W911NF-16-1-0307. Further support was provided by the National Geospatial-Intelligence Agency award #HM0177-13-1-0008 and NASA awards #NNX16AH88G and #NNX17AJ35G.
Internal waves -- Mathematical models, Internal waves -- Remote sensing, Tidal currents
A near-global model for the sea-surface expression of the baroclinic tide has been developed using exact-repeat mission altimetry. The methodology used differs in detail from other altimetry-based estimates of the open ocean baroclinic tide, but it leads to estimates which are broadly similar to previous results. It may be used for prediction of the baroclinic sea level anomaly at the frequencies of the main diurnal and semidiurnal tides, K1, O1, M2, S2, as well as the annual modulates of M2, denoted MA2 and MB2. Based on a comparison with independent CryoSat-2 data, the tidal predictions are capable of explaining more than 13 cm2 variance at a few locations. The predicted tides are also validated by comparison with a database of hourly currents inferred from drogued surface drifters. The database is large enough to permit assessment of a simple model for scattering of the low-mode tide. Results indicate a scattering time scale of approximately one day, consistent with a priori estimates of time-variable refraction by the mesoscale circulation.
Zaron, Edward, "Baroclinic Tidal Sea Level from Exact-Repeat Mission Altimetry" (2018). Portland Institute for Computational Science Publications. 10.