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Welcome to the free ocean tide loading provider

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January 20, 2018: Gravity (and Tilt) are undergoing a revision.
This part of the service remains disabled until further notice. The reason being that results have been inconsistent between the computation sites as to tilt orientation. Also, the measurement units have caused misunderstanding (r.t.f.h.!, h. meaning the BLQ HEADER), and we have to crack our heads how to communicate with sufficient emphasis.
December 24, 2017: Global grids of tide-induced displacements avaiilable
November 10, 2017: New tide model added: GOT.4.10c
August 4, 2017: New version of converter script for BLQ to TSOFT, g-Software (Micro'g Lacoste), and now also ETERNA
We offer a converter script (in perl v.5.8.8). To run it under MS Windows, read here.
Please issue -h  for usage.
February 12, 2017: Speedier service for jobs forwarded to Segal.  
Clients who request calculations with the high-resolution models FES2014b, FES2012 and TPXO8-Atlas had previously to wait in the queue at OSO until their job was in the top position. Now, the job queue is processed separately, and high-resolution jobs are relayed to Segal immediately (i.e. with 10 seconds delay at maximum).
November 1 and September 26, 2016: New Tide Models.  
As eagerly awaited in the user community, we have added FES2014b, FES2012 and TPXO8-Atlas to the available range of Ocean tide models, thanks to the efforts of Machiel.
The computations are automatically forwarded to SEGAL at UBI/IDL in Portugal, so that the receivers of the parameter files would notice as small changes as possible, and - if the machines and their connections are working - none at all as regards basic user interaction and delivery.
As of yet, a few options won't work with the relayed jobs: There's no plot option and no live job activity-and-queue report.
SEGAL is a facility at the University of Beira Interior and Institute Dom Luiz.

July 20, 2012: Time series from BLQ-files -  Program ttimm

June 20, 2011: mGal is not an SI unit,
and the numbers in the BLQ result files lack numerical resolution.
Thus a change in conventions was made:
Henceforth, if you select Gravity, the results are presented in μm/s2.
However, you can select "mGal" if you still prefer that.

(old news)


Global grids of ocean tide loading displacements in netCDF-format and medium resolution are now available. Please read the instructions presented when you follow the link. Feedback is highly welcome. The new set is provided as-is, no service is included except the promise that we inform those users that left us a note of updates and bug reports.
Machiel Bos and HGS are currently working towards augmenting the Loading Provider with a new set of high-resolution grids, much more actual and user-friendly, we hope. Goal: Ready in the first quarter of 2018.


With the growing number of precise geodetic observations, the requests for ocean tide loading values have increased considerably. Therefore, this webpage has been created in the hope it will help the geodetic community. Just select an ocean tide model, tick the required type of loading, fill in the coordinates of the stations, give your e-mail address and press the submit button. The program will check if it can read your input and if so, it will calculate the values and send the results to you by e-mail. The program will take about 5 minutes per station. An example of the output in normal BLQ-formal can be found here while an example of the output in the new HARPOS-format can be found here .

If you find it tiresome to go through our web interface, you can send email to the loading provider in a special format.

Select ocean tide model

A brief description of the ocean tide models can be found here.

What type of loading phenomenon do you consider
vertical and horizontal displacements
gravity μm/s2 and tilt 0.1 μrad         TEMPORARILY OUT OF SERVICE
gravity mGal and tilt μrad               TEMPORARILY OUT OF SERVICE

N.B. Together with gravity parameters the BLQ-files are complemented with tilt parameters. As the BLQ-format is not optimal to cover the dynamic range of tilt, don't hesitate to contact me at    hgs kanelbulle chalmers dot se    to receive the parameters in a more suitable form.

using Greens function
(We are working towards a visco-elastic option.)

If you have selected vertical and horizontal displacements, you can correct for the centre of mass motion of the Earth due to the ocean tides . ( NO   means your frame origin is in the solid earth centre, YES  that it is in the joint mass centre of solid earth and ocean.)
Do you want to correct your loading values for the motion?

Want a plot? (New feature of Sep. 4, 2011)
The plots show the near-field resolution of the coastline. They are generated for each site that involves the loading post-processor OLMPP. Compare with the comment information in the result file.
Fetch it here after you received the results. Look for your user name: name-olmpp1.png name-olmpp2.png etc.

What kind of output format is required?
 BLQ (normal) 

Gravity loading parameters for TSOFT and g-Software can be converted from BLQ with

Where are your stations? 
In the following form up to one hundred stations can be entered but each station should be on a separate line. The height of the station above sea level is irrelevant for ocean tide load modelling of displacements: it is not necessary to input this parameter, it can be safely omitted.

Name of station_________| |Longitude (deg) | Latitude (deg) | Height (m)     OR
Name of station_________| X (m) Y (m) Z (m)

(Our fixed column layout: 24 characters for the station, 25'th column blank, then three numerical fields with a width of 16 characters each, no TAB characters please!)

What is your e-mail address?

Note: Because of a large amount of misuse we deny requests with return addresses at a couple of notorious domains.

No reply?
If you do not get a reply within a few hours, please have a look at our collection of undeliverable mail (it should work again) and
check that you have supplied a correct email-address.
Your job may be in the queue. Have a look here, it's updated every minute.
If you find the results useful, please cite this website mentioning the names M.S. Bos and H.-G. Scherneck. 

The 20-m VLBI telescope

Last updated: July 27, 2011
Send comments or questions to Hans-Georg Scherneck, hgs kanelbulle