Scientific needs and requirements for a better glider

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Scientific needs and requirements for a better glider data management (Ocean. Gliders perspective but

Scientific needs and requirements for a better glider data management (Ocean. Gliders perspective but not only) Pierre Testor et al. 18 -20 September 2018, Genova, Italy

Ocean science for society and GOOS requirements Ocean data need to be quality controlled

Ocean science for society and GOOS requirements Ocean data need to be quality controlled and disseminated to the public – in RT for ocean forecasting services and applications – in DM for assessment of the ocean variability on the long term with better quality control, and corrections if necessary and archived. This implies sustained observations and concerns a number of Essential Ocean Variables (EOVs) for which present measurement capacities are considered as mature enough to be included in the global system (T, S, O 2, Chl-a, currents. . . ) • Climate • Real time Services • Ocean health

Ocean. Gliders perspective From the Ocean. Gliders global and long term perspective, there at

Ocean. Gliders perspective From the Ocean. Gliders global and long term perspective, there at the moment 3 themes (and there will be soon other themes): Boundary currents Storms Water transformation for which gliders can fill gaps and deliver useful data at the global scale and on the long term in such a single framework. A global glider management framework addressing real time AND delayed modes would allow to set up common procedures/methodologies for each theme and cross-themes. to look at glider data at the global scale and bring new knowledge for these 3 themes, not yet revealed by other platforms: explain the geographical differences, possible teleconnections impact of large scales on regional/local scales and vice-versa, . . . to facilitate integration with other platforms (profiling floats, moorings, research cruises, XBTs, . . . ) for the sake not only of long-term ocean observations (GOOS) but also process studies

Stakeholders/workflows in Glider Data Management A lot of progress has been made on the

Stakeholders/workflows in Glider Data Management A lot of progress has been made on the RT data management with metadata definition, RT quality control procedures. That is one of the main reason of the acceptance of Ocean. Gliders by WMO/IOC JCOMM. Success story ! The DM data management was left for the PIs. → Poor PIs !

Gliders and process studies (e. g. DEWEX) Objective analyses at seasonal scale MLD AW

Gliders and process studies (e. g. DEWEX) Objective analyses at seasonal scale MLD AW - Sal (0 -100 m) (Fr/Es/It: national and EU projects) Study of deep convection process and impact on marine ecosystem LIW – Pot. Temp. (400 -600 m) Gliders, profiling floats, R/V cruises, moorings over a seasonal cycle → Observing and modelling (many teams involved) Testor et al. 2018: Multiscale Observations of Deep Convection in the Northwestern Mediterranean Sea during Winter 2012– 2013 Using Multiple Platforms, JGR Chl (0 -bottom)

Gliders and process studies (e. g. DEWEX) MLD Pot. Density (900 -1000 m) Objective

Gliders and process studies (e. g. DEWEX) MLD Pot. Density (900 -1000 m) Objective analyses at 10 days scale MLD, density over layers → 3 D view every 10 days of the water properties (OGCM-like but only in situ observations) Estimates of volumes of density classes over time First robust estimates of deep water formation rates Unprecedented benchmark for modelling

Gliders and process studies (e. g. DEWEX) MLD Pot. Density (900 -1000 m) Objective

Gliders and process studies (e. g. DEWEX) MLD Pot. Density (900 -1000 m) Objective analyses at 10 days scale MLD, density over layers → 3 D view every 10 days of the water properties (OGCM-like but only in situ observations) Estimates of volumes of density classes over time First robust estimates of deep water formation rates Unprecedented benchmark for modelling

Gliders and process studies (e. g. DEWEX) The optimal combination of different platforms allowed

Gliders and process studies (e. g. DEWEX) The optimal combination of different platforms allowed a coverage of profile observations never reached before → new quantitative aspects Key role of gliders linking - Eulerian and Lagrangian other observations - the coastal/slope and open sea environment (but almost useless without the other obs. ) Detailed and thorough analysis of the processes. Submesoscale: central role of SCVs, Symmetric Instability, and interactions between plumes/SCVs and the bottom nepheloid layer → New paradigm on the deep convection phenomenon and its impact on ocean ventilation and marine ecosystem Scalable approach, could be applied to other phenomena, not yet realistic on the mid/long term considering the present resources Black: density contours Blue shade: ventilated waters

Need for integration, data harmonization Need for integration and harmonization of all data (gliders,

Need for integration, data harmonization Need for integration and harmonization of all data (gliders, profiling floats, CTDs, moorings, . . . ) to maximize the information. In the DEWEX study, all “profiles” could be considered the same regardless of the platform type (which also applies many other applications, e. g. modelling, data assimilation). But difficult to do ! Need to aggregate data from different sources and different formats and to make platformdependent corrections in DM to create a consistent data set. General idea → CTD casts from R/V (pre/post calibration and water samples analyses) = reference for the autonomous platforms (gliders, floats, moorings) for which specific processing was needed. For gliders and such a study, data management solutions were not yet efficient enough. There were some undesired gaps and drops in the data flow even in RT and Delayed Mode data are often not available (need to go at the source to get them right). So, bi-lateral agreements between the glider teams corrections were made with in-house routines on all gliders (for consistency): Mana with 2 Ph. D students + 1 p pre/post calibrations when possible Short term contracts, tu Impossible values, spikes checks S: sensor and thermal lags, T-S diagram checks offset corrections O 2: alignment and lag corrections, offset corrections Chl-a: harmonization with satellite images (black/scale), U, V, W: flight model (require technical info not always available yet in common formats) cross-comparison with other gliders and other platforms

Some ideas/suggestions The (RT AND) DM workflow needs to be implemented on a global

Some ideas/suggestions The (RT AND) DM workflow needs to be implemented on a global scale including each glider team carrying out long term observations, but not only. There should be home for others. Intercomparison exercices and regional expertise could be left to the “poor” PIs (or maybe better to regional centers? ) but a lot can be automated to help them for the other required processing, and this should be done at the DAC level in a sustained way. PIs are solicited a lot and can not alone ensure the DM QC. The present EOV (T, S, O 2, Chl-a, current) need to be managed for gliders with approved and common procedures for QC and adjustments in RT AND DM. Plans have to be made for other EOVs (nitrates, turbidity, ADCP, acoustics, video, . . . ).

Stakeholders/workflows in Glider Data Management ! lp He M D h wit Dissemination and

Stakeholders/workflows in Glider Data Management ! lp He M D h wit Dissemination and efficient collaboration on DM data If not, it will be difficult to engage new teams and “newbies”, students, new staff, but also experts with peculiar skills (e. g. experts in BGC, data assimilation, neural networks, . . . ) in the analysis and promotion of glider data. Good science requires collaboration, information exchange and optimization of the resources → need for an efficient glider data management to reach out Visibility and sustainability (incl. Archiving) ensure the DM data are available for an assessment of the status against targets in a regional/global programmatic perspective

Some ideas/suggestions Governance exists : Ocean. Gliders ST and associated regional bodies like the

Some ideas/suggestions Governance exists : Ocean. Gliders ST and associated regional bodies like the Euro. GOOS GTT. IOOS, IMOS and EGO formats will inevitably evolve. We have to cope with that in a sustained way and we must aim for only 1 format, the Ocean. Gliders format, and 3 operating GDACs. Meanwhile, translators, or code sharing, could fix some issues but not ideal. Need to organize Data Management meetings at the global and regional scales on an annual basis. Detailed action plans. Progress against tartgets. Distribution of work is required (limited resources). Need for a Ocean. Gliders Technical Coordinator at JCOMMOPS for the metadata management and point-of-contact for integrators. We hope to open this position within the next few months.

Grazzie !

Grazzie !