1. Action ES0904 European Gliding Observatories Network (EGO) Final Symposium Simón Ruiz (Spain) Daniel Hayes (Cyprus) WG5 leaders Kiel, 16-17June 2014

2. Outline Objectives WG5. Tasks. Endurance lines and glider fleets experiments. Glider data analysis and merging. Gliders and modelling. Summary. 2

3. 3 Scope WG5- Action ES0904 This WG focus on the way to conduct fields operations with fleets of gliders to gather detailed and accurate 4D oceanic data sets related to different specific research requirements. Of particular interest here are the large trans-oceanic sections (such as RAPID section) or boundary current sections (often referred as “Endurance lines”) for large scale or regional budgets as well as the investigation of mesoscale and submesoscale phenomena in specific areas. This task will use the piloting facilities developed by WG3, including adaptive sampling techniques together with associated data analysis tools. Part of this work will be done in cooperation with the community of operational modelling that will provide both the forecasts to assess the distribution of glider over the sections or shape of the fleet to cover as well as the modelling platforms themselves in order to perform detailed post processing of the collected data. Proposed deliverables: -Glider fleet field campaigns methodologies and reports on the performed campaigns. -Development and tests of data analysis tools for registering and fusing data gathered from multiple gliders with other source of data. -Assessment on techniques (including data assimilation into operational systems) for retrieval of 4-D oceanic parameters from high resolutions surveys for physical and biogeochemical parameters.

4. 4 Endurance lines Balearic Channels – Western Mediterranean RAPID program – 26ºN Canary Islands Fram Strait program – North Atlantic MOOSE program – Northwestern Mediterranean Nice CalviMenorca Mallorca Fuerteventura

5. 5 Red dots show the location of glider profiles starting from deployment of the coast of Gran Canaria, followed by transit to the operation site on the 1000m contour off Morocco. Magenta crosses indicate the locations of the RAPID moorings. Endurance lines: case 1 Rapid program Dynamic height difference between 200m and 800m: gray = from glider before removal of internal tide; black = de-tided glider data magenta = corresponding values from mooring (40-hour low pass filtered). The yellow shows the dynamic height difference 10m to 110m from glider data. Smeed & Wright (2009)

6. 6 Endurance lines: case 2 Ibiza Channel Heslop et al., 2012, GRL

7. 7 Nice Calvi Menorca Endurance lines: case 3 Northwestern Med Piterbarg et al., 2014, JMS

8. 8 Endurance lines: case 4 Fram Strait program (Beszczynska-Möller et al., 2012)

9. 9 Fleet of gliders SWARM experiment From September 2012 until May 2013 (GROOM, JERICO TNA, PERSEUS, NOMR12, MISTRALS, MOOSE) - 8 gliders - (Sub)-mesoscale process - Transports - Deep convection - Modelling

10. 10 Glider fleet camapaings Tropical waters SWARM01 experiment near Cabo Verde Islands March, 2010 6 gliders Temporal variability of physical and biogeochemical parameters

11. 11 Glider fleet campaings EYE Experiment WARM CORE CYPRUS EDDY December 2012 6 gliders 2 profiling floats 4 surface drifter Shipborne measurements

12. 12 Data analysis and fusing data Gliders for ocean processes oriented studies: Merging glider data with altimetry / Argo / moorings. Boundary currents, tranports and sub-mesoscale processes. Vertical velocities estimation. Ocean mixing/convection and impact on heat content and biogeochemistry. Upwelling. Sediment fluxes. Model validation / assimilation. Water properties around submarine vulcano subtropical waters. Coastal waves Frontal variabiality Polar regions ….. More than 50 SCI papers Exhaustive list of references can be found at: http://www.ego-network.org/dokuwiki/doku.php?id=public:references

13. 13 Data analysis and fusing data: Examples Surface plot of temperature and salinity in the basin site (LION) between 1 December 2011 and 1 June 2012 Durrieu de Madron et al., GRL, 2013 Cascading and deep convection Durrieu de Madron et al., GRL, 2013 Cascading and deep convection Vertical section of temperature (a,b), density (c,d), and B-V (e,f) Ruiz et al., GRL, 2012 Upper ocean mixing Oxygen section concentration 2–23 December 2007. Isopycnals are drawn in gray Ullgren et al., JGR, 2013 Water interactions Temperature distribution in the upper 12m (a, b) potential energy of the upper 10m (c, d), vertical integrated velocity from glider (e, f), Karstensen et al., 2014, Biogeosc., Summer Upwelling

14. 14 Gliders and modelling Averaged fields between glider assimilation (left) and control (right) analyses on 23 December 2004 Dobricic et al., 2010, Dyn. Atm. and Oce. Glider data assimilation Dobricic et al., 2010, Dyn. Atm. and Oce. Glider data assimilation Mourre and Alvarez, 2012, Ocea. Dyn. Super-ensamble multi modellling Mourre and Alvarez, 2012, Ocea. Dyn. Super-ensamble multi modellling 3DSE temperature forecast at 80-meter depth produced on 29 August 2010 and valid for 1 September 00:00 (t0+72 h). Right: associated uncertainty (yellow squares display the position of assimilated observations at this depth)

15. 15 Summary - Gliders represent a revolution for the characterization of mesoscale and sub-mesoscale ocean processes. - Gliders data can be merged with data from other platforms (moorings, Argo, Altimetry) to complement the view of the 3D state of the ocean. - Endurance lines: Gliders are useful in shelf areas where other platforms such as Argo are rare or ship sampling can not be mantained regularly. - Fleet campaings: Successful field experiments in the Atlantic, Pacific ocean and in the Mediterraean Sea. - Useful for modelling (validation and data assimilation).

16. Thank you 16

17. 17 Data analysis and fusing Methodology to combine glider and altimetry To obtain a 3D field, the method combines: - The vertical modes of DH from glider (vertical dependent) - The gridded altimetry data (x,y) In the case of a single dominant mode, the modelled profile can be expressed as: Altimetry glider For diagnosing vertical velocities (Omega-equation) we need a 3D DH field. Method for reconstruction (JAOT, Pascual and Gomis, 2003) Thus, obtaining the single amplitude corresponding to each profile A 1 (x, y) would be straightforward given the surface altimetry data and the surface component of the leading EOF [EOF1(p0)] from glider data.

18. Reconstructed field Dynamic height (cm) Solid: original profile Dashed: reconstructed Dynamic height (cm)

19. 19 Glider fleet campaings: Case 1 : REP13 experiment

20. 20 Glider fleet campaings: Case 1 : REP13 experiment