Arc5km2018: Arctic Ocean Inverse Tide Model on a 5 kilometer grid, 2018

The Arctic Ocean Tidal Inverse Model developed in 2018 (Arc5km2018) is a barotropic tide model on an idealized 5 kilometer polar stereographic grid. It is an update to the original Arctic Ocean Tidal Inverse Model (AOTIM5) model developed in 2004 (Padman and Erofeeva, 2004). Arc5km2018 was created using the OSU Tidal Inversion Software (OTIS) package. The bathymetry grid is based on the original International Bathymetric Chart of the Arctic Ocean (IBCAO) bathymetry (Jakobsson et al., 2000). Arc5km2018 was developed using the scheme described in Egbert and Erofeeva (2002), and consists of grids of sea surface height and depth-integrated currents ("volume transports") for each of 12 tidal constituents; 5 semidiurnal (M2, S2, K2, N2, 2N2), 4 diurnal (K1, O1, P1, Q1), and 3 non-linear (M4, MS4, MN4). Arc5km2018 assimilates coastal and benthic tide gauges, and TOPEX/Poseidon/Jason and European Space Agency (ESA) satellite radar altimetry, to improve the five largest-amplitude constituents, M2, S2, N2, K1 and O1. Arc5km2018 includes the following updates relative to AOTIM5: (1) it uses an improved prior model with ocean open boundary forcing from an updated TOPEX/Poseidon global barotropic global tide solution (TPXO9.1); (2) it adds four tidal constituents, 2N2 and the three non-linear constituents; and (3) it assimilates much longer time series of altimetry, notably from the ESA satellites that sample to 81.5 degrees north.
We recommend that users compare results from Arc5km2018 and AOTIM5, which is also available at the Arctic Data Center, before deciding which to use for a specific application. Please also check the ESR Polar Tide Model webpage for more recent Arctic barotropic tide models.

Egbert, G. D., and S. Y. Erofeeva (2002), Efficient inverse modeling of barotropic ocean tides, Journal of Atmospheric and Oceanic Technology, 19(2), 183-204.

Padman, L., and S. Erofeeva (2004), A barotropic inverse tidal model for the Arctic Ocean, Geophysical Research Letters, 31(2), L02303.