Presentation on theme: "Sustained Monitoring in the Timor Passage, Ombai Strait and Australian NWS Susan Wijffels, Bernadette Sloyan, CSIRO Craig Steinberg, AIMS."— Presentation transcript:
Sustained Monitoring in the Timor Passage, Ombai Strait and Australian NWS Susan Wijffels, Bernadette Sloyan, CSIRO Craig Steinberg, AIMS
INSTANT: A PROCESS STUDY Gaps in INSTANT Outflow measurements -Sunda -Australian North West Shelf (very wide and shallow, but warm) Total ITF 15 Sv (1Sv = 10 6 m 3 s -1 ) Ombai and Timor Passage comprise >80% of ITF transport.
INSTANT: A PROCESS STUDY Timor Strait – mean along strait flow
CSIRO. Insert presentation title, do not remove CSIRO from start of footer Timor Section in the BlueLink Reanalysis (10km) Mean Strongest EOFs
INSTANT: A PROCESS STUDY Ombai Strait – mean along strait flow
DESIGN Cross shelf array extending across Timor Trench – all moorings located on Jason altimeter track Ombai location – same as INSTANT S. Ombai/JADE Mooring site
IMOS ITF, Kimberley & Pilbara Array
DESIGN High tension moorings similar to INSTANT Upward 150kHz or 300kHz ADCP Downward 750kHz ADCP Point TP (S) up to ~20-30m. Point TPV (S) down to sill Also deployed a PIES in Ombai Strait - could this help extrapolate temperature to the surface Shelf array 6 months servicing schedule Tall moorings 18 month servicing schedule
IMOS IndoFLOW MOORINGS The Indonesian Throughflow array monitoring the Ombai Strait and Timor Passage was completed on 22 June The Ombai and Timor Sill moorings are in 3000 – 3400 m, and the Timor North mooring is in 1114 m.
TIMOR South: Raw Current Profiles over 400m Speed Direction Jul 2010 Dec 2010 Speed Direction Oct 2010
IMOS IndoFLOW MOORINGS
Mooring deployments take between 3 to 5 hours. In Ombai Strait gas and cargo ships (approx 300m long) gave us room to drift onto the mooring site.
La Nina fresh cap Comparison on 2011 and INSTANT 2003 Temperature, Salinity and Density profiles (0-200 m) in the Timor Passage
La Nina Fresh Cap
Salinity changes CTD Oct 2002-Sep 2003 Oct 1999-Sep 2002
Predicted salinity change over the top 180 metres in the Indo-Australian Basin and observations Change due to combined P-E of Indo-Australian Basin and Banda Sea (lagged by 1 year) Change due to P-E in Indo-Australian Basin Predicted change = V orig – (V orig.S orig + V fresh.S fresh ) / (V orig + V fresh ) V orig = 180 m 3, S orig = 34.5, S fresh = 4 Phillips et al, GRL, 2005
CONCLUSIONS AND FUTURE DIRECTIONS The Timor Passage and Ombai Strait are now monitored. This begin the long-term monitoring of the Indonesian Throughflow Comparison of Upper Ocean temperature, salinity and density profiles between 2003 and 2011 show large variability in the mixed layer and subsurface. Freshening in surface layer the result of La Nina conditions. The mooring time-series data (current, temperature and salinity) will be available via the IMOS data portal. Working with international collaborators to have the Lombok Strait re-instrumented.
PLANS 1 st turnaround of tall moorings on RV Southern Surveyor in September 2012 swath the cross-strait transect to the sidewalls LADCP/CTD sections – sidewall boundary layer thickness (structure is a major source of error in net transport) synthesis shelf/deep transects for full transport estimates assess the use of the PIES (combined with satellite SST) in addressing near surface temperature gap
Issues / Opportunities We can have the total outflow if we can instrument Lombok Strait – this question should be a focus of TT Piggy back additional measurements on the cruises. ACCESS/Synthesis Can only happen if we follow the CLIVAR principles of free and open sharing of data Can we put all CLIVAR ITF mooring data in one place (or links to the data from one place)?? aim for transport (volume,heat/unit depth) products for use by modeling community
ACKNOWLEDGEMENTS We thank the Master and crew of the RV Solander for their outstanding cooperation and hard work during the voyage. John Leutchford provided invaluable assistance with pre-voyage planning and electronic, computer and vessel support during the voyage. We particularly thank Peter Doherty and Frank Tirendi (AIMS) for their assistance in facilitating the cruise and the government of Timor Leste for granting permission to carry out this research. Finally we thank Akasio Dos and Nelio Arnaldo, Timor Leste observers, for their assistance during the voyage. This cruise was sponsored by the Australian Integrated Marine Observing System, CSIRO and AIMS.