FES2014

Introduction

FES2014 is the last version of the FES (Finite Element Solution) tide model released in 2016 and developed in collaboration with CLS, LEGOS, NOVELTIS and within a CNES funded project. A new database was developed based on this model containing 34 tidal constituents distributed on 1/16° grids (amplitude and phase). More information can be found at: AVISO and CLS. This database was rearranged in a HDF5 file ready to use in MOHID. FES2014 tidal components can be used in MOHID by using a method described in the next sub sections.

Quick start

You need to have two input files: a HDF5 file with the FES2014 tidal components database, and a input text file for tides.

• Get the HDF5 input file with tidal components here: [1]. (Warning: the filesize is about 9GB and the download can take some time). In case you have problems downloading the file please contact operational at mohid.com
• prepare the input file for tides:
  • If you use MOHID GUI, you have to prepare a text file which content is described in the section below. The path of the file has to be defined in the interface as explained here: [2].
  • If you use MOHID Studio, you have to prepare a file Tide_*.dat (where * is the simulation number), which content is described in the section below.
• Finally, in the Hydrodynamic_*.dat input file, you should set TIDE : 1; You should do this either if you use MOHID Studio or MOHID GUI.

Input File

Here's what the input text file should look like :

• Sample input:

TRIANGULATION         : 0
FILE_TIDAL_COMPONENTS : C:\Tide_fes2014\FES2014.hdf5


<beginHDFgauges>

EXTRAPOLATE           : 1
HARMONICS             : 1
EXTRACT_HARMONICS     : 1
SPATIAL_INTERPOL      : 1
HARMONICS_FIELD_DIM   : M2/amplitude

NAME        : water level
UNITS       : m 

LONGITUDE   : 25 40 18.00
LATITUDE    : 16 56 31.88
METRIC_X    : -16.942188
METRIC_Y    : 32.627598
REF_LEVEL   : 2.1
TIME_REF    : 0.000000

<<beginharmonics>>
SA
SSA
MU2
NU2
MSF
2N2
J1
K1
K2
L2
M2
M3
M4
M6
M8
MF
MKS2
MM
MN4
MS4
N2
O1
P1
Q1
R2
S1
S2
S4
T2
EPS2
LDA2
<<endharmonics>>
   
<endHDFgauges>

the keyword FILE_TIDAL_COMPONENTS defines the HDF file that you downloaded at the Quick start section [3]

MOHID assumes that must generate levels from harmonic component in all points of the open boundary. However, the user can define in the input file the following keyword:

FILE_GAUGES_LOCATION  : TidalGaugeLocation.xyz

The file defined by the keyword FILE_GAUGES_LOCATION contains tidal gauge locations in a xyz file format. The steps to generate the tidal gauge location file are here: [4] (Step 1 only). If the tidal gauge location file is given, the water level is generated from the harmonic components at the points defined in the tidal gauge location file. Then levels at the point of open border are imposed by interpolation.

Compilation options

If you get an error saying "Forrtl: severe (170): Program exception - stack overflow", This means that before to compile the MOHID code you should increase the stack size in the MOHID water properties pages under the Visual Studio MohidNumerics Project.

References

Carrere L, Lyard F, Cancet M, Guillot A, Picot N. FES 2014, a new tidal model – Validation results and perspectives for improvements, presentation to ESA Living Planet Conference, Prague 2016.

Lyard FH, Allain DJ, Cancet M, Carrère L, Picot N. FES2014 global ocean tide atlas: design and performance. Ocean Science. 2021; 17(3): 615-649. Available at: Download.

Aviso Website : [5]