TPXO9-atlas is our latest 1/30 degree resolution fully global solution, obtained by combining 1/6 degree base global solution TPXO9.v1 and thirty 1/30 degree resolution local solutions for all coastal areas, including Arctic and Antarctic. All TPXO9-atlas patches were obtained using consistent bathymetry and boundary conditions from TPXO9 base solution, using the same altimetry data sets for assimilation. The local solution boundaries are shown above with frames on the background of TPXO9-atlas M2 elevation amplitude (color) and phase (contours).

We provide both TPXO9-atlas 1/30 degree resolution and TPXO9 1/6 degree base global solution in two popular formats:

  1. our traditional binary format (OTPS format);

  2. netcdf format

Since the files are large, we provide one tidal constituent per file. OTPS (nc) does allow to work with multiple single-constituent TPXO9-atlas files. MATLAB toolbox TMD does not. Script tpxo_atlas2local.m can be used as TMD plug_in. The script makes a multi-constituent outcut from the single constituent TPXO8-atlas binary files for an area of your choice. This multi-constituent outcut can then be used with TMD.

Download tpxo_atlas2local.m for Linux/macOS

Download tpxo_atlas2local.m for Windows

TPXO9-atlas is set of elevation/transport files one constituent per file and bathymetry. TPXO9v* includes two multi-constituent files of elevations/transports and bathymetry.

TPXO9-atlas latest version: v4, release Dec 24, 2020: MED and CHJ patches updated using SRTM15 bathymetry and Natural Earth coastline version 4.1.0.

v3, release Nov 1, 2020: improvements in ANT, using SRTM15 bathymetry and SCAR Antarctic Digital Database coast line; ARC, HBB, ESB, IND, SAN, using SRTM15 bathymetry and Natural Earth coastline version 4.1.0.

TPXO9-atlas-v3/v4 fits on average 3% more of CryoSat variance in Arctic and 1.5% more in Antarctic compared to TPXO9-atlas-v2

TPXO9v4a - multi-constituent global 1/6 degree resolution hybrid product. It is the same as TPXO9.v1 in the open ocean, and it is averaged TPXO9-atlas-v4 onto TPXO9 1/6 degree resolution grid in coastal areas. Release Dec 24, 2020

TPXO9v1, TPXO9v4a and TPXO9-atlas-v4 are available for academic research and other non-commercial uses and require registration.


TPXO9 models can be licensed for commercial use at modest cost - please contact Dr. Erofeeva or Prof. Egbert on details. Our customers are eligible for free upgrades within one year.

To refer to our models/software in your publications please use the citation:

Egbert, Gary D., and Svetlana Y. Erofeeva. "Efficient inverse modeling of barotropic ocean tides." Journal of Atmospheric and Oceanic Technology 19.2 (2002): 183-204.

Check out our TPXO Web Service to get tide predictions from TPXO9-atlas at any location and time.