In-situ based reanalysis of the global ocean temperature and salinity with ISAS: variability of the heat content and steric height

The In Situ Analysis System (ISAS) was developed to produce gridded fields of temperature and salinity that preserve as much as possible the time and space sampling capabilities of the Argo network of profiling floats. Since the first global re-analysis performed in 2009, the system has evolved and a careful delayed mode processing of the 2002-2012 dataset has been carried out using version 6 of ISAS and updating the statistics to produce the ISAS13 analysis. This last version is now implemented as the operational analysis tool at the Coriolis data centre. The robustness of the results with respect to the system evolution is explored through global quantities of climatological interest: the Ocean Heat Content and the Steric Height. Estimates of errors consistent with the methodology are computed. This study shows that building reliable statistics on the fields is fundamental to improve the monthly estimates and to determine the absolute error bars. The new mean fields and variances deduced from the ISAS13 re-analysis and dataset show significant changes relative to the previous ISAS estimates, in particular in the southern ocean, justifying the iterative procedure. During the decade covered by Argo, the intermediate waters appear warmer and saltier in the North Atlantic and fresher in the Southern Ocean than in WOA05 long term mean. At inter-annual scale, the impact of ENSO on the Ocean Heat Content and Steric Height is observed during the 2006-2007 and 2009-2010 events captured by the network.

Long-Term In Situ Survey of Reactive Iron Concentrations at the EMSO-Azores Observatory

A study of the temporal dynamics of iron concentrations and temperature on a faunal assemblage at the Lucky Strike vent was performed using the Tempo ecological module at the EMSO-Azores deep-sea observatory. The CHEMINI in situ analyzer was implemented on this structure to determine reactive iron concentrations in unfiltered seawater samples along with a temperature probe. Stability tests were performed on the CHEMINI analyzer before deployment (optical module, hyperbaric tests, and deep-sea calibration) for long-term in situ analysis of reactive iron (six months, 2013–2014) at the Tour Eiffel active edifice. Recorded daily, the in situ standard (25 \mu mol.L {}^{-1} ) showed excellent reproducibility (1.07%, n=522 ), confirming satisfactory analytical performance of the CHEMINI analyzer and thus validating the iron concentrations measured by the instrument. Furthermore, the analyzer proved to be reliable and robust over time. The averaged reactive iron concentration for the six-month period remained low ([Fe] =text{7.12}\pm text{2.11} \mu mol.L {}^{-1} , n=519 ), but showed some noticeable variations with temperature. Reactive iron concentrations and temperature were significantly correlated emphasizing reactive iron stabilization over the time of deployment. Period spectra indicated strong tidal influence and relevant frequencies of four to five days for both variables.

Copernicus In Situ TAC, Real Time Quality Control for WAVES

In April 2017, CMEMS plans to launch the WAVES NRT products. This document is focused in the automatic RTQC of the collected wave data. The validation procedure includes the delayed mode quality control of the data and will be specified in another guideline. To perform any kind of quality control to wave data, first it’s necessary to know the nature of the measurements and the analysis performed to those measurements to obtain the wave parameters. For that reason next chapter is dedicated to show the usual wave analysis and the different parameters and estimators obtained.