PRODUCT USER MANUAL
For the GLOBAL Ocean Sea Physical Analysis and
Forecasting Products
GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Issue: 1.1
Contributors: L.Nouel
CMEMS version scope : Version 2.0
Approval Date :
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GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Ref: CMEMS-GLO-PUM-001-024
Date
: September 21 2016
Issue
: 1.1
CHANGE RECORD
Issue
Date
§
1.0
21/09/2016 All
Description of Change
Author
Validated By
initial version
L.NOUEL
Y Drillet
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TABLE OF CONTENTS
I
INTRODUCTION ......................................................................................................................................... 5
I.1 Description summary .................................................................................................................................. 5
I.2 History of changes ....................................................................................................................................... 5
II
HOW TO DOWNLOAD A PRODUCT ......................................................................................................... 6
III
DESCRIPTION OF THE PRODUCT SPECIFICATION ...................................................................... 7
III.1 General Information ................................................................................................................................ 7
III.2 Production subsystem description .......................................................................................................... 8
III.2.1
The physical high resolution (HR) global system ......................................................................... 8
III.3 Details of products contents .................................................................................................................... 8
IV
NOMENCLATURE OF FILES .................................................................................................................. 10
IV.1 Domain coverage .................................................................................................................................... 10
IV.2 Vertical Levels ........................................................................................................................................ 11
IV.3 Temporal extend of analysis and forecast stored on delivery mechanism ........................................ 11
V
FILE FORMAT ........................................................................................................................................... 12
V.1 Netcdf ........................................................................................................................................................ 12
V.2 Structure and semantic of NetCDF files ................................................................................................ 12
V.3 Reading software...................................................................................................................................... 22
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GLOSSARY AND ABBREVIATIONS
MFC
Monitoring and Forecasting Centre
Med
Mediterranean
NetCDF
Network Common Data Form
CF
Climate Forecast (convention for NetCDF)
SSS
Sea surface salinity
SSC
Sea surface currents
SSH
Sea surface height
RMS
Root mean square
SDN
SeaDataNet (climatology)
CHL
Chlorophyll
SLA
Sea Level Anomalies
PC
Production Center
PU
Production Unit
Meridional Velocity
West to East component of the horizontal velocity vector
Zonal Velocity
South to North component of the horizontal velocity vector
ftp
Protocol to download files
OpenDAP
Open-Source Project for a Network Data Access Protocol. Protocol to
download subset of data from a n-dimensional gridded dataset (ie: 4
dimensions: lon-lat,depth,time)
Subsetter
CMEMS service tool to download a NetCDF file of a selected geographical
box using values of longitude an latitude, and time range
Directgetfile
CMEMS service tool (FTP like) to download a NetCDF file
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I
Date
: September 21 2016
Issue
: 1.1
INTRODUCTION
I.1 Description summary
This document is the user manual for the CMEMS global analysis and forecast product
GLOBAL_ANALYSIS_FORECAST_PHY_001_024: It provides with aggregated analyses updated weekly
with 10-day forecast (updated daily). A 2-years rolling archive is stored on the CMEMS server.
It contains 3D potential temperature, salinity and currents information from top to bottom global
ocean and 2D sea surface level, sea ice thickness, sea ice fraction and sea ice velocities information.
This product is global with dedicated projection and spatial resolution (see IV.1). It is defined on a
standard collocated grid at 1/12 degree (approx. 8km) (all variables on the same grid points) and on
50 standard levels. It is interpolated on a 1/12 degree and 50 vertical levels regular grid from the
1/12 degree and 50 vertical levels Arakawa C native grid.
GLOBAL_ANALYSIS_FORECAST_PHY_001_024 product is organised in two datasets.

global-analysis-forecast-phy-001-024 which contains the 3D daily mean fields: 3D potential
temperature, salinity and currents information from top to bottom global ocean and 2D sea
surface level, sea ice thickness, sea ice fraction and sea ice velocities information.

global-analysis-forecast-phy-001-024-hourly-t-u-v-ssh which contains the hourly mean
surface fields: potential temperature, salinity, currents and sea surface level information.
It is updated as follows:
-
Every week, the time series covering two full years in the past up to real-time and forecast up
to 7 days is updated at the end of the operational production process.
-
Every day, the time series (from the current day up to 10 days in the future) is updated at the
end of the operational production process. Old obsolete forecasts are deleted from the
server.
The product is published on the CMEMS dissemination server after automatic and human quality
controls. Product is available on-line and disseminated through the CMEMS Information System. Files
downloaded on the MIS are in NetCDF format and follows CF-1.4 convention.
The analysis and forecasting system is described in the Quality Information Document (QUID)
CMEMS_GLO_QUID_001_024. More detailed information can be obtained from the CMEMS Service
Desk ([email protected] ).
I.2 History of changes
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II
Date
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Issue
: 1.1
HOW TO DOWNLOAD A PRODUCT
The product is available through the CMEMS Web Portal Subsetter Service.
You first need to register. Please find below the registration steps:
http://marine.copernicus.eu/web/34-products-and-services-faq.php#1
Once registered, the CMEMS FAQ: http://marine.copernicus.eu/services-portfolio/technical-faq/ will
guide you on How to download a product through the CMEMS Web Portal Subsetter Service.
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III DESCRIPTION OF THE PRODUCT SPECIFICATION
III.1 General Information
Product Specification
GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Geographical coverage
Global
Variables
Temperature
Salinity
Sea surface height
Horizontal velocity (eastward and northward components)
Sea ice concentration
Sea ice velocity (eastward and northward components)
Sea ice thickness1
Sea floor potential temperature
Density ocean mixed layer thickness
Each week
Each day
Analysis
Yes
No
Forecast
Yes
Yes
Available time series


Daily mean: Hindcast start 2 
years ago up to real-time + 7

day forecast
Daily mean: 10-day forecast
High frequency (1h): 10-day
forecast
High frequency (1h): Hindcast
start 2 years ago up to realtime + 7 day forecast
Target delivery time
Updated weekly, Thursday, before Updated daily, before noon (12 am
noon (12 am UTC)
UTC)
Temporal resolution

Daily mean for the 2D and 3D above variables

High frequency (hourly mean) for Sea surface height, Sea Surface
Temperature and Sea Surface Horizontal velocity
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Delivery mechanism
Subsetter, DGF
Horizontal resolution
1/12 ° (equirectangular grid)
Number of vertical levels
50 from -5500.0m to 0.0m
Format
NetCDF CF1.4
Date
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Issue
: 1.1
Table 1: GLOBAL_ANALYSIS_FORECAST_PHY_001_024 product specification.
Detailed information on the
http://marine.copernicus.eu/ .
systems
and
products
are
on
CMEMS
web
site:
III.2 Production subsystem description
III.2.1
The physical high resolution (HR) global system
The Operational Mercator global ocean analysis and forecast system at 1/12 degree is providing 10
days of 3D global ocean forecasts updated daily and ocean analysis updated weekly. The time series
start on December 27, 2006 and is aggregated in time in order to reach a two full year’s time series
sliding window. This product includes daily mean files of temperature, salinity, currents, sea level,
mixed layer depth and ice parameters from the top to the bottom over the global ocean. It also
includes hourly mean surface fields for sea level height, temperature and currents.
For detailed description, see CMEMS_GLO_QUID_001_024
III.3 Details of products contents
Dataset name
global-analysis-forecast-phy001-024
contains the 3D daily
mean
fields:
3D
potential temperature,
salinity and currents
information from top to
bottom global ocean and
Parameter usual
name
Variable name
Standard_name
units
sea_water_potential_temperature
Temperature
thetao
Salinity
so
Eastward ocean
current velocity
uo
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Kelvin
sea_water_salinity
psu
eastward_sea_water_velocity
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-1
m.s
Ref: CMEMS-GLO-PUM-001-024
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Product GLOBAL_ANALYSIS_FORECAST_PHY_001_024
2D sea surface level, sea
ice thickness, sea ice
fraction and sea ice
velocities information.
global-analysis-forecastphy-001-024-hourly-t-uv-ssh
contains the hourly
mean surface fields:
potential temperature,
salinity, currents and
surface sea surface level
information.
Date
: September 21 2016
Issue
: 1.1
Northward ocean
current velocity
vo
northward_sea_water_velocity
Sea surface height
zos
Ice concentration
siconc
sea ice eastward
velocity
usi
sea ice northward
velocity
vsi
Sea ice thickness
sithick
sea_ice_thickness
m
Density ocean mixed
layer thickness
mlotst
ocean_mixed_layer_thickness_defined_
by_sigma_theta
m
Sea floor potential
temperature
bottomT
sea_water_potential_temperature_at_s
ea_floor
Kelvin
Potential
temperature
thetao
Eastward ocean
current velocity
uo
Northward ocean
current velocity
vo
Sea surface height
zos
sea_surface_height_above_geoid
sea_ice_area_fraction
-1
m.s
m
1
eastward_sea_ice_velocity
northward_sea_ice_velocity
sea_water_potential_temperature
eastward_sea_water_velocity
northward_sea_water_velocity
-1
m.s
-1
m.s
Kelvin
-1
m.s
-1
m.s
sea_surface_height_above_geoid
m
Table 2: List of the variables for each dataset and their names in the NetCDF files for the
GLOBAL_ANALYSIS_FORECAST_PHY_001_024 product.
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IV NOMENCLATURE OF FILES
GLOBAL_ANALYSIS_FORECAST_PHY_001_024 files nomenclature download from MIS is based on
product dataset name and a numerical reference related to the request date on the MIS subsetter.
The scheme is:
datasetname_nnnnnnnnnnnnn.nc
datasetname is a character string within one of the following :
-
global-analysis-forecast-phy-001-024
-
nnnnnnnnnnnnn: 13 digit integer corresponding to the current time (download time) in
milliseconds since January 1, 1970 midnight UTC.
-
nc: standard NetCDF filename extension.
Example: global-analysis-forecast-phy-001-024_1303461772348.nc
IV.1 Domain coverage
Dataset
name
globalanalysisforecastphy-001-024
Domain
Global
Boundaries
180°W-180°E
89°S-90°N
Projection
Resolution
Grid size
Image
1/12°
Regular
4320x2041
Native model outputs are interpolated on standard grids.
Regular projection is plane chart
-
Longitude and latitude step is constant
-
Longitude step is equal to latitude step
- Longitude and latitude coordinates are 1D
array
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IV.2 Vertical Levels
50 levels GLO datasets
depth = 0.494025, 1.541375, 2.645669, 3.819495, 5.078224, 6.440614, 7.92956,
9.572997, 11.405, 13.46714, 15.81007, 18.49556, 21.59882, 25.21141,
29.44473, 34.43415, 40.34405, 47.37369, 55.76429, 65.80727, 77.85385,
92.32607, 109.7293, 130.666, 155.8507, 186.1256, 222.4752, 266.0403,
318.1274, 380.213, 453.9377, 541.0889, 643.5668, 763.3331, 902.3393,
1062.44, 1245.291, 1452.251, 1684.284, 1941.893, 2225.078, 2533.336,
2865.703, 3220.82, 3597.032, 3992.484, 4405.224, 4833.291, 5274.784,
5727.917;
IV.3 Temporal extend of analysis and forecast stored on delivery mechanism
The product is updated as follows:
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V
Date
: September 21 2016
Issue
: 1.1
FILE FORMAT
V.1 Netcdf
The products are stored using the NetCDF format.
NetCDF (network Common Data Form) is an interface for array-oriented data access and a library
that provides an implementation of the interface. The NetCDF library also defines a machineindependent format for representing scientific data. Together, the interface, library, and format
support the creation, access, and sharing of scientific data. The NetCDF software was developed at
the Unidata Program Center in Boulder, Colorado. The NetCDF libraries define a machineindependent format for representing scientific data.
Please see Unidata NetCDF pages for more information, and to retrieve NetCDF software package.
NetCDF data is:
* Self-Describing. A netCDF file includes information about the data it contains.
* Architecture-independent. A NetCDF file is represented in a form that can be accessed by
computers with different ways of storing integers, characters, and floating-point numbers.
* Direct-access. A small subset of a large dataset may be accessed efficiently, without first reading
through all the preceding data.
* Appendable. Data can be appended to a NetCDF dataset along one dimension without copying
the dataset or redefining its structure. The structure of a NetCDF dataset can be changed, though this
sometimes causes the dataset to be copied.
* Sharable. One writer and multiple readers may simultaneously access the same NetCDF file.
V.2 Structure and semantic of NetCDF files
Here is an example of NetCDF structure (result of command ncdump) of a daily mean file that can be
retrieved via the CMEMS subsetter.
netcdf mercatorpsy4v3r1_gl12_mean_20160617_R20160622 {
dimensions:
longitude = 4320 ;
latitude = 2041 ;
depth = 50 ;
time = UNLIMITED ; // (1 currently)
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variables:
float longitude(longitude) ;
longitude:valid_min = -180.f ;
longitude:valid_max = 179.9167f ;
longitude:step = 0.08332825f ;
longitude:units = "degrees_east" ;
longitude:unit_long = "Degrees East" ;
longitude:long_name = "Longitude" ;
longitude:standard_name = "longitude" ;
longitude:axis = "X" ;
float latitude(latitude) ;
latitude:valid_min = -80.f ;
latitude:valid_max = 90.f ;
latitude:step = 0.08333588f ;
latitude:units = "degrees_north" ;
latitude:unit_long = "Degrees North" ;
latitude:long_name = "Latitude" ;
latitude:standard_name = "latitude" ;
latitude:axis = "Y" ;
float depth(depth) ;
depth:valid_min = 0.494025f ;
depth:valid_max = 5727.917f ;
depth:units = "m" ;
depth:positive = "down" ;
depth:unit_long = "Meters" ;
depth:long_name = "Depth" ;
depth:standard_name = "depth" ;
depth:axis = "Z" ;
float time(time) ;
time:long_name = "Time (hours since 1950-01-01)" ;
time:standard_name = "time" ;
time:calendar = "gregorian" ;
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time:valid_min = 582600.f ;
time:valid_max = 582600.f ;
time:units = "hours since 1950-01-01 00:00:00" ;
time:axis = "T" ;
short mlotst(time, latitude, longitude) ;
mlotst:long_name = "Density ocean mixed layer thickness" ;
mlotst:standard_name = "ocean_mixed_layer_thickness_defined_by_sigma_theta" ;
mlotst:units = "m" ;
mlotst:unit_long = "Meters" ;
mlotst:add_offset = -0.152592554688454 ;
mlotst:scale_factor = 0.152592554688454 ;
mlotst:_FillValue = -32767s ;
mlotst:valid_min = 1s ;
mlotst:valid_max = 4345s ;
mlotst:cell_methods = "area: mean" ;
short zos(time, latitude, longitude) ;
zos:long_name = "Sea surface height" ;
zos:standard_name = "sea_surface_height_above_geoid" ;
zos:units = "m" ;
zos:unit_long = "Meters" ;
zos:add_offset = 0. ;
zos:scale_factor = 0.000305185094475746 ;
zos:_FillValue = -32767s ;
zos:valid_min = -6503s ;
zos:valid_max = 5406s ;
zos:cell_methods = "area: mean" ;
short bottomT(time, latitude, longitude) ;
bottomT:long_name = "Sea floor potential temperature" ;
bottomT:standard_name = "sea_water_potential_temperature_at_sea_floor" ;
bottomT:units = "K" ;
bottomT:unit_long = "Kelvin" ;
bottomT:_FillValue = -32767s ;
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bottomT:add_offset = 294.15 ;
bottomT:scale_factor = 0.000732444226741791 ;
bottomT:valid_min = -32722s ;
bottomT:valid_max = 19769s ;
bottomT:cell_methods = "area: mean" ;
short sithick(time, latitude, longitude) ;
sithick:long_name = "Sea ice thickness" ;
sithick:standard_name = "sea_ice_thickness" ;
sithick:units = "m" ;
sithick:unit_long = "Meters" ;
sithick:add_offset = -0.000762962736189365 ;
sithick:scale_factor = 0.000762962736189365 ;
sithick:_FillValue = -32767s ;
sithick:valid_min = 1s ;
sithick:valid_max = 7957s ;
sithick:cell_methods = "area: mean where sea_ice" ;
short siconc(time, latitude, longitude) ;
siconc:long_name = "Ice concentration" ;
siconc:standard_name = "sea_ice_area_fraction" ;
siconc:units = "1" ;
siconc:unit_long = "Fraction" ;
siconc:add_offset = -3.81481368094683e-05 ;
siconc:scale_factor = 3.81481368094683e-05 ;
siconc:_FillValue = -32767s ;
siconc:valid_min = 1s ;
siconc:valid_max = 27719s ;
siconc:cell_methods = "area: mean where sea_ice" ;
short usi(time, latitude, longitude) ;
usi:long_name = "Sea ice eastward velocity" ;
usi:standard_name = "eastward_sea_ice_velocity" ;
usi:units = "m s-1" ;
usi:unit_long = "Meters per second" ;
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usi:add_offset = 0. ;
usi:scale_factor = 3.05185094475746e-05 ;
usi:_FillValue = -32767s ;
usi:valid_min = -30988s ;
usi:valid_max = 32150s ;
usi:cell_methods = "area: mean where sea_ice" ;
short vsi(time, latitude, longitude) ;
vsi:long_name = "Sea ice northward velocity" ;
vsi:standard_name = "northward_sea_ice_velocity" ;
vsi:units = "m s-1" ;
vsi:unit_long = "Meters per second" ;
vsi:add_offset = 0. ;
vsi:scale_factor = 3.05185094475746e-05 ;
vsi:_FillValue = -32767s ;
vsi:valid_min = -25452s ;
vsi:valid_max = 20562s ;
vsi:cell_methods = "area: mean where sea_ice" ;
short thetao(time, depth, latitude, longitude) ;
thetao:long_name = "Temperature" ;
thetao:standard_name = "sea_water_potential_temperature" ;
thetao:units = "degrees_C" ;
thetao:unit_long = "Degrees Celsius" ;
thetao:_FillValue = -32767s ;
thetao:add_offset = 21. ;
thetao:scale_factor = 0.000732444226741791 ;
thetao:valid_min = -32393s ;
thetao:valid_max = 19749s ;
thetao:cell_methods = "area: mean" ;
short so(time, depth, latitude, longitude) ;
so:long_name = "Salinity" ;
so:standard_name = "sea_water_salinity" ;
so:units = "1e-3" ;
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so:unit_long = "Practical Salinity Unit" ;
so:_FillValue = -32767s ;
so:add_offset = -0.00152592547237873 ;
so:scale_factor = 0.00152592547237873 ;
so:valid_min = 1s ;
so:valid_max = 28456s ;
so:cell_methods = "area: mean" ;
short uo(time, depth, latitude, longitude) ;
uo:long_name = "Eastward velocity" ;
uo:standard_name = "eastward_sea_water_velocity" ;
uo:units = "m s-1" ;
uo:unit_long = "Meters per second" ;
uo:_FillValue = -32767s ;
uo:add_offset = 0. ;
uo:scale_factor = 0.000610370188951492 ;
uo:valid_min = -3633s ;
uo:valid_max = 4513s ;
uo:cell_methods = "area: mean" ;
short vo(time, depth, latitude, longitude) ;
vo:long_name = "Northward velocity" ;
vo:standard_name = "northward_sea_water_velocity" ;
vo:units = "m s-1" ;
vo:unit_long = "Meters per second" ;
vo:_FillValue = -32767s ;
vo:add_offset = 0. ;
vo:scale_factor = 0.000610370188951492 ;
vo:valid_min = -3091s ;
vo:valid_max = 3728s ;
vo:cell_methods = "area: mean" ;
// global attributes:
:title = "daily mean fields from Global Ocean Physics Analysis and Forecast updated
Daily" ;
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:easting = "longitude" ;
:northing = "latitude" ;
:history = "2016/08/09 15:23:08 MERCATOR OCEAN Netcdf creation" ;
:source = "MERCATOR PSY4V3R1" ;
:institution = "MERCATOR OCEAN" ;
:references = "http://www.mercator-ocean.fr" ;
:comment = "CMEMS product" ;
:Conventions = "CF-1.4" ;
:domain_name = "GL12" ;
:field_type = "mean" ;
:field_date = "2016-06-17 00:00:00" ;
:field_julian_date = 24274.f ;
:julian_day_unit = "days since 1950-01-01 00:00:00" ;
:forecast_range = "9-day_forecast" ;
:forecast_type = "hindcast" ;
:bulletin_date = "2016-06-22 00:00:00" ;
:bulletin_type = "operational" ;
:longitude_min = -180.f ;
:longitude_max = 179.9167f ;
:latitude_min = -80.f ;
:latitude_max = 90.f ;
:z_min = 0.494025f ;
:z_max = 5727.917f ;
}
Here is an example of NetCDF structure (result of command ncdump) of a high frequency (h) file that
can be retrieved via the CMEMS subsetter.
netcdf mercatorpsy4v3r1_gl12_hrly_20160101_R20160106 {
dimensions:
longitude = 4320 ;
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latitude = 2041 ;
depth = 1 ;
time = UNLIMITED ; // (24 currently)
variables:
float longitude(longitude) ;
longitude:valid_min = -180.f ;
longitude:valid_max = 179.9167f ;
longitude:step = 0.08332825f ;
longitude:units = "degrees_east" ;
longitude:unit_long = "Degrees East" ;
longitude:long_name = "Longitude" ;
longitude:standard_name = "longitude" ;
longitude:axis = "X" ;
float latitude(latitude) ;
latitude:valid_min = -80.f ;
latitude:valid_max = 90.f ;
latitude:step = 0.08333588f ;
latitude:units = "degrees_north" ;
latitude:unit_long = "Degrees North" ;
latitude:long_name = "Latitude" ;
latitude:standard_name = "latitude" ;
latitude:axis = "Y" ;
float depth(depth) ;
depth:valid_min = 0.494025f ;
depth:valid_max = 0.494025f ;
depth:units = "m" ;
depth:positive = "down" ;
depth:unit_long = "Meters" ;
depth:long_name = "Depth" ;
depth:standard_name = "depth" ;
depth:axis = "Z" ;
float time(time) ;
© EU Copernicus Marine Service – Public
Page 19/ 22
Ref: CMEMS-GLO-PUM-001-024
PUM for GLOBAL Sea Physical Analysis and Forecasting
Product GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Date
: September 21 2016
Issue
: 1.1
time:long_name = "Time (hours since 1950-01-01)" ;
time:standard_name = "time" ;
time:calendar = "gregorian" ;
time:valid_min = 578545.f ;
time:valid_max = 578568.f ;
time:units = "hours since 1950-01-01 00:00:00" ;
time:axis = "T" ;
short zos(time, depth, latitude, longitude) ;
zos:long_name = "Sea surface height" ;
zos:standard_name = "sea_surface_height_above_geoid" ;
zos:units = "m" ;
zos:unit_long = "Meters" ;
zos:add_offset = 0. ;
zos:scale_factor = 0.000305185094475746 ;
zos:_FillValue = -32767s ;
zos:valid_min = -6353s ;
zos:valid_max = 5286s ;
zos:cell_methods = "area: mean" ;
short thetao(time, depth, latitude, longitude) ;
thetao:long_name = "Temperature" ;
thetao:standard_name = "sea_water_potential_temperature" ;
thetao:units = "degrees_C" ;
thetao:unit_long = "Degrees Celsius" ;
thetao:_FillValue = -32767s ;
thetao:add_offset = 294.15 ;
thetao:scale_factor = 0.000732444226741791 ;
thetao:valid_min = -32765s ;
thetao:valid_max = 17313s ;
thetao:cell_methods = "area: mean" ;
short uo(time, depth, latitude, longitude) ;
uo:long_name = "Eastward velocity" ;
uo:standard_name = "eastward_sea_water_velocity" ;
© EU Copernicus Marine Service – Public
Page 20/ 22
Ref: CMEMS-GLO-PUM-001-024
PUM for GLOBAL Sea Physical Analysis and Forecasting
Product GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Date
: September 21 2016
Issue
: 1.1
uo:units = "m s-1" ;
uo:unit_long = "Meters per second" ;
uo:_FillValue = -32767s ;
uo:add_offset = 0. ;
uo:scale_factor = 0.000610370188951492 ;
uo:valid_min = -3754s ;
uo:valid_max = 3916s ;
uo:cell_methods = "area: mean" ;
short vo(time, depth, latitude, longitude) ;
vo:long_name = "Northward velocity" ;
vo:standard_name = "northward_sea_water_velocity" ;
vo:units = "m s-1" ;
vo:unit_long = "Meters per second" ;
vo:_FillValue = -32767s ;
vo:add_offset = 0. ;
vo:scale_factor = 0.000610370188951492 ;
vo:valid_min = -3469s ;
vo:valid_max = 3620s ;
vo:cell_methods = "area: mean" ;
// global attributes:
:title = "hourly mean fields from Global Ocean Physics Analysis and Forecast updated
Daily" ;
:easting = "longitude" ;
:northing = "latitude" ;
:history = "2016/08/03 17:40:11 MERCATOR OCEAN Netcdf creation" ;
:source = "MERCATOR PSY4V3R1" ;
:institution = "MERCATOR OCEAN" ;
:references = "http://www.mercator-ocean.fr" ;
:comment = "CMEMS product" ;
:Conventions = "CF-1.4" ;
:domain_name = "GL12" ;
:field_type = "mean" ;
© EU Copernicus Marine Service – Public
Page 21/ 22
Ref: CMEMS-GLO-PUM-001-024
PUM for GLOBAL Sea Physical Analysis and Forecasting
Product GLOBAL_ANALYSIS_FORECAST_PHY_001_024
Date
: September 21 2016
Issue
: 1.1
:field_date = "2016-01-01 00:00:00" ;
:field_julian_date = 24106.f ;
:julian_day_unit = "days since 1950-01-01 00:00:00" ;
:forecast_range = "9-day_forecast" ;
:forecast_type = "hindcast" ;
:bulletin_date = "2016-01-06 00:00:00" ;
:bulletin_type = "operational" ;
:longitude_min = -180.f ;
:longitude_max = 179.9167f ;
:latitude_min = -80.f ;
:latitude_max = 90.f ;
:z_min = 0.494025f ;
:z_max = 0.494025f ;
}
V.3 Reading software
NetCDF data can be browsed and used through a number of software, like:



ncBrowse: http://www.epic.noaa.gov/java/ncBrowse/,
NetCDF Operator (NCO): http://nco.sourceforge.net/
IDL, Matlab, GMT…
Useful information on UNIDATA: http://www.unidata.ucar.edu/software/netcdf/
Remember: Real_Value = (Display_Value X
© EU Copernicus Marine Service – Public
scale_factor) + add_offset
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