Argo user’s manual V3.41

This document is the Argo data user’s manual. It contains the description of the formats and files produced by the Argo Data Assembly Centres (DACs)

Argo Core and BGC merged profiles file processing and format on Coriolis GDAC

In 2014, Argo data management team decided to split core-Argo profiles and non-core-Argo profiles into two distinct profile files (C-File and B-File). Both files have the same N_PROF dimension and, for each N_PROF, pressure values of the C-file are duplicated into the B-File. A core-Argo profile file (C-File) contains the Core parameters provided by a float: pressure, temperature, salinity and conductivity. The additional parameters are managed in a BGC-Argo data file (B-File). Two types of additional parameters are concerned: ‘intermediate’ parameters (provided by the float sensors) and BGC parameters (directly sampled by the float sensors or computed, at the DAC level, from Core and ‘intermediate’ parameters). For a given float cycle and direction, the merged profile combines into one merged file (M-File) the Core and the BGC parameters. The M-File is generated by the GDAC, from the C-File and B-File provided by the DACs. M-profile version 1 In version 1, the M-Profile is created from a concatenation of Core and BGC parameters (i.e. ‘intermediate’ parameters are ignored) along the common PRES axis of each N_PROF. Thus M-profile file has the same number of N_PROF arrays as the original C-File and B-File. M-profile version 2 In version 2, the M-Profile is the merging of all N_PROF arrays of M-Profile version 1 into a single one. Thus, in such M-Profile file: - N_PROF = 1 - N_PARAM is equal to the number of Core and BGC parameters The standard Argo profile structure is still used in M-Profile file: measurements are stored in a(N_PROF, N_LEVELS) array. However, as N_PROF = 1, we can consider that measurements are reported in a simple “matrix” of N_PARAM * N_LEVELS dimension: one column for each Core and BGC parameter, one level for each valid distinct pressure. The PRES vertical synthetic axis contains the sorted set of all valid distinct pressures. A valid pressure has a QC flag of ‘1’, ‘2’, ‘5’ or ‘8’ (‘good’, ‘probably good’, ‘changed’ or ‘estimated’ value). The number of valid distinct pressures is equal to N_LEVELS. Each parameter value having a non-valid pressure is ignored. A pressure value may have more than one value for a parameter (for example, BGC sensors may report specific Core parameter values that has been used to compute reported BGC parameter values). If the parameter is a Core-parameter, the value of the Core profile is selected. Otherwise, the first value of an ordered set (see “N_PROF priority” below) of the original N_PROF arrays is selected. This document details the processing steps used to generate version 2 of merged profile data from Argo profile data. It also describes the format of the NetCDF files produced by the Coriolis GDAC to store these merged profile data

Argo Quality Control Manual for CTD and Trajectory Data

A CTD (conductivity, temperature, depth) device measures temperature and salinity versus pressure. This document is the Argo quality control manual for CTD and trajectory data. It describes two levels of quality control: - The first level is the real-time system that performs a set of agreed automatic checks. - The second level of quality control is the delayed-mode system. These quality control procedures are applied to the parameters JULD, LATITUDE, LONGITUDE, PRES, TEMP, PSAL, and CNDC

Global hydrographic variability patterns during 2003–2008.

International audienceMonthly gridded global temperature and salinity fields from the near-surface layer down to 2000 m depth based on Argo measurements are used to analyze large-scale variability patterns on annual to interannual time scales during the years 2003–2008. Previous estimates of global hydrographic fluctuations have been derived using different data sets, partly on the basis of scarce sampling. The substantial advantage of this study includes a detailed summary of global variability patterns based on a single and more uniform database. In the upper 400 m, regions of strong seasonal salinity changes differ from regions of strong seasonal temperature changes, and large amplitudes of seasonal salinity are observed in the upper tropical and subpolar global ocean. Strong interannual and decadal changes superimpose long-term changes at northern midlatitudes. In the subtropical and tropical basin, interannual fluctuations dominate the upper 500 m depth. At southern midlatitudes, hydrographic changes occur on interannual and decadal time scales, while long-term changes are predominantly observed in the salinity field. Global mean heat content and steric height changes are clearly associated with a positive trend during the 6 years of measurements. The global 6-year trend of steric height deduced from in situ measurements explains 40% of the satellite-derived quantities. The global freshwater content does not show a significant trend and is dominated by interannual variability

Wind-Driven cross-equatorial flow in the Indian Ocean

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