Editing
Editing to compute SSH on oceans
Reminder
SSH= orbit
- range
- corrections
SLA= SSH - SSH moyenne
MSS = MDT + geoid
(see )
To detect and remove data on ice there are several possible criteria:
- latitude> |50°|:
- Number of 20Hz measurement (num_18hz_ku_ocean) < 17
- |MWR – ECMWF| (|mod_wet_tropo_corr - mwr_wet_tropo_corr |)> 10cm
- Peakiness: ku_peak> 2
- |Sigma0(Ku)-Sigma0(S)| (|ku_ocean_bscat_coeff - s_ocean_bscat_coeff |)> 5dB
Requirements on min/max values
If one of the following requirements is not respected, the point must be removed.
Description |
Parameter |
Min value |
Max value |
---|---|---|---|
number of valid points |
num_18hz_ku_ocean |
10 |
- |
SSH |
- |
-130000 mm |
100000 mm |
SLA |
- |
-2000 mm |
2000 mm |
Rms of range at 20Hz |
sd_18hz_ku_ocean |
0 |
250 mm |
Off nadir angle |
off_nad_ang_wvform |
-2000 10-4deg2 |
1600 10-4deg2 |
Dry troposphere |
mod_dry_tropo_corr |
-2500 mm |
-1900 mm |
Inverse barometer inverse |
inv_barom_corr ou ib_MOG2D_NF |
-2000 mm |
2000 mm |
Wet troposphere from radiometer |
mwr_wet_tropo_corr |
-500 mm |
-1 mm |
Ionospheric correction |
ra2_ion_corr_ku |
-400 mm |
40 mm |
Significant wave hights in ku band |
ku_sig_wv_ht |
0 mm |
11000 mm |
Sea state bias |
sea_bias_ku ou ssb_cls |
-500 mm |
0 mm |
Backscatter coefficient (coeff de rétrodiffusion) |
ku_ocean_bscat_coeff /100 |
7.0 dB |
30.0 dB |
Oceanic tide FES04 |
ocean_tide_FES_04 |
-5000 mm |
5000 mm |
Long period ocean tide |
long_period_ocn_tide_ht |
-500 mm |
500 mm |
Solid earth tide |
solid_earth_tide_ht |
-1000 mm |
1000 mm |
Polar tide |
geocen_pole_tide_ht |
-5000 mm |
5000 mm |
Wind speed from altimeter |
ra2_wind_sp |
0 mm/s |
30000 mm/s |
Land flag |
altim_landocean_flag a 0 ou 1 |
|
|
SSH computation
Description |
Parametre selection (parameters recommended by CTOH are in bold) |
sign |
unity (for binary format) |
Comments |
---|---|---|---|---|
Altitude |
alt_cog_ellip |
"+" |
mm |
|
Range |
ku_band_ocean_range |
"-" |
mm |
|
Ionosphere correction |
ra2_ion_corr_ku |
"-" |
mm |
|
|
ra2_ion_corr_s |
"-" |
mm |
|
|
ion_corr_doris_ku |
"-" |
mm |
|
|
ion_corr_doris_s |
"-" |
mm |
|
|
ion_corr_mod_ku |
"-" |
mm |
|
|
ion_corr_mod_s |
"-" |
mm |
|
|
gim_ku |
"-" |
mm |
|
|
gim_s |
"-" |
mm |
|
|
iono_lis (*) |
"-" |
mm |
|
Dry troposphere correction |
mod_dry_tropo_corr |
"-" |
mm |
|
Wet troposphere correction |
mwr_wet_tropo_corr |
"-" |
mm |
|
|
mod_wet_tropo_corr |
"-" |
mm |
|
|
wet_tropo_cls (*) |
"-" |
mm |
|
Sea state bias |
sea_bias_ku |
"-" |
mm |
|
|
sea_bias_c |
"-" |
mm |
|
Inverse barometer |
inv_barom_corr |
"-" |
mm |
|
|
ib_MOG2D_NF(*) |
"-" |
10-5m |
This correction includes the inverse barometer effetcs and also the non linear wind effects and of the ocean dynamic |
|
ib_ECMWF_NF (*) |
"-" |
10-5m |
|
Ocean tide |
tot_geocen_ocn_tide_ht_sol1 |
"-" |
mm |
|
|
tot_geocen_ocn_tide_ht_sol2 |
"-" |
mm |
|
|
ocean_tide_l_GOT00 (*) |
"-" |
mm |
Does not include the load tide, nor the permanent tide. |
|
ocean_tide_FES04 (*) |
"-" |
mm |
Does not include the load tide, nor the permanent tide. |
Long tide period |
long_period_ocn_tide_ht |
"-" |
mm |
Not to be used with GDR ocean tide models (already included). |
Polar tide |
geocen_pole_tide_ht |
"-" |
mm |
|
Solide tide |
solid_earth_tide_ht |
"-" |
mm |
|
Load tide |
tidal_load_ht |
"-" |
mm |
Not to be used with GDR ocean tide models (already included). |
MSS |
m_sea_surf_ht |
|
mm |
|
(*) Data added by the CTOH (all the others are already provided with the GDR)
Document Actions