Dr. Anthony Grehan + MSR 3.2 Team

Transcription

1 Modelling MPAs The use of ROV s for offshore benthic surveys in Irish waters Dr. Anthony Grehan + MSR 3.2 Team Earth and Ocean Sciences, NUIG, Ireland,

2 Outline Review ROV surveys in Irish waters Rationale for MSR 3.2 CE 0505 as a case study Lessons to be learnt? Equipment Operating constraints

3 Chronology of ROV Surveys in the Irish offshore 2004 Olu, Karine & Shipboard Party (2002). Caracole cruise Report (Cobh to Foynes), 30 th July to 15 th August, 2001, volumes 1 and 2. Freiwald, A. & Shipboard Party (2002). RV Poseidon Cruise 292 (Reykjavik Galway), 15 th July to 4 th August, 2002, 86 pp. Klages, M., Thiede, J. and Foucher, J.-P. (editors) (2004). The Expedition ARKTIS XIX/3 of the Research Vessel Polarstern in Berichte zur Polar- und Meeresforschung, Vol Dorschel, B., D. Hebbeln, V. Ratmeyer & Shipboard Party (2004). Meteor M61 Leg 3 (Cork to Ponta Delgada), 4 th June to 21 st June, 2004, pp O Donnell, C. & Shipboard Party (2005). Orange Roughy Acoustic Stock Assessment Programme. CE0205 Cruise Report, Marine Institute, Ireland. Grehan, A.J., Wilson, M., Guinan, J., Ullgren, J., Riordan, J., Rooney, S., Sacchetti, F. and Shipboard Party (2005). Ocean habitat mapping in deep-waters off the west coast of Ireland using a Remotely Operated Vehicle. CE0505 Cruise Report, Department of Earth and Ocean Sciences, NUI, Galway.? 2006 Van Rooij, D., Henriet, J.-P. & Shipboard Party (2006). Cruise Report Belgica 06/12 HERMES Belgica GEO, "La Chapelle Bank". RCMG internal publication, 27 pp. Fitzpatrick, F. & Shipboard Party (2007). CE0907 Cruise Report? Marine Institute, Ireland Henriet, J.P. & Shipboard Party (2007). Cruise Report Belgica? 2008 Bett, B.. & Shipboard Party (2008). ISIS ROV survey of Goban Channel? National Oceanographic Centre, Southampton.

4 Summary of ROV Survey Infrastructure No Year Survey Ship Lead ROV Class Navigation System MB TMS Caracole L Atalante FR Victor Work Horse POSIDONIA X X POS 292 Poseidon D Cherokee Inspection ARK 3/A Polarstern D/FR Victor Work Horse POSIDONIA M61-3 Meteor D Quest Work GAPS X Horse CE0205 Celtic Explorer IE Aglantha Inspection GAPS X X CE0505 Celtic Explorer IE Bathysaurus Hybrid GAPS/ PHINS X BEL06/12 Belgica BE Genesis Inspection GAPS X ? CE0907? Celtic Explorer IE?? GAPS/ PHINS? X ? BEL Belgica BE Genesis Inspection GAPS X ? HERMES? UK ISIS Work? X X Horse

5 PRTLI Cycle 3 MSR 3.2 Completed multi-beam survey of Ireland s deep water territory (Zone 3) INSS map products at 1:250,000 scale Data available to NUIG under MOU Zoom into data for habitat mapping and other research projects

6 MSR 3.2: Multibeam & habitat mapping on the continental slope high-frequency MBES low-frequency MBES ROV high-frequency MBES Extend coverage of direct observation with acquisition of near bottom MB Not to scale

7 Multi-scale analysis of multibeam data and video ground-truthing Derive information which is potentially more relevant to habitat than bathymetry alone Terrain analysis slope, aspect, roughness etc. Multiple scales important assess terrain at local and regional level make informed choice of analysis scale(s) Video ground-truthing Link to habitat classification schemes Provide new information for habitat suitability modeling Relate seabed terrain to the distribution of fauna

8 Research Cruise CE0505 June 2005 R.V. Celtic Explorer RT PB PSB Bathysaurus ROV First Irish-led deep water ROV habitat survey technical and scientific partnership NUIG/UL ROV multibeam and video surveys high resolution mapping and non-destructive observations of habitat/fauna Use INSS data to identify survey targets and plan surveys essential data for cost effective survey

9 Scientific data acquisition including: ROV multibeam - Reson Seabat 8125 ROV based video - vertical (SDI) and oblique (CCD) colour cameras All supported by high quality position & motion data using INS+DVL (IXSEA Phins) Develop cost effective survey strategy Cognisant of very strong bottom currents (tidal)

10 BEL 47, Belgica Mounds,Porcupine Seabight Fine scale structure of mound revealed by ROV survey Mound general shape revealed by INSS ship-borne survey INSS data: 25m resolution ROV data: 50cm resolution INSS data: 25m grid ROV data: 0.5m grid Can we get more information from the multibeam data than just bathymetry?

11 Terrain analysis & geo-referenced video observations Visual comparison Extract raster values for statistical comparison Terrain Analysis Slope Can we predict habitat beyond the track? Aspect Scale issues but very good co-location of data-sets Curvature Amenable for training habitat-suitability models Roughness

12 Southern Porcupine Mounds: first look Arc Mounds Explorer Mound

13 Southern Mound Province, south Porcupine Bank: Explorer Mound Faunal composition similar to Therese Mound, in PSB Main mound 130 m high part of small complex Striking hexactinellid sponge characteristic of this site

14 Survey Considerations

15

16

17

18

19 Distribution of wind strength during ARK XIX/3c Frequency (%) Beaufort Force Approximate that Force 5 produces wave height of 3m +

20

21 Cruise planning considerations Tidal currents can be high along slope Weather sub-optimal for ROV surveys Always need Plan B TMS recommended particularly if video mosaicing required Multi-beam can provide useful means of scaling up from small area video survey

22 There are still some fish in the sea.. Acknowledgments: University of Limerick, RV Celtic Explorer, Argus Remote Systems, Geological Survey of Ireland, Marine Institute, Higher Education Authority

23 MSR 3.2 NUIG/UL Shipboard Team CE0505

24