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OceanCurrent - Data sources

Sea Surface Temperature

Thermal imagery from the AVHRR sensors on the NOAA polar-orbiting environmental satellites are processed by the IMOS Satellite Remote Sensing Facility. The high-resolution images shown on this website use the national-coverage GHRSST L3U product produced by the Bureau of Meteorology for IMOS, from the HRPT data downlinked since ~1982 from the satellites by Australian ground stations in Perth (WASTAC), Darwin and Melbourne (BoM), Hobart (CSIRO) and Townsville (AIMS). We monitor the availability over the last 30 days and region-specific coverage of this data set using our [SST data coverage monitoring] system. The analysis is repeated three times a day. In the upper panel, red indicates high data density while blue can mean either cloudy conditions, or lack of data from the satellites. The lower panel shows the availability of data from individual NOAA satellites.

Ocean Colour

Ocean colour imagery from the MODIS sensor on NASA's Terra and Aqua satellites is processed by the IMOS Satellite Remote Sensing Facility. We obtain the 1-day composite chlorophyll-a estimates (which are essentially unaveraged over time because most of the ocean is only seen once a day) from the SRS thredds server and show it here in two forms: daily data in the small-region maps, and latest-data composite for the whole Australasian region. In March 2015, the SRS released a new version of the entire dataset so we re-generated all our graphics (also with more of the other IMOS in-situ data included) just in time for the launch of OceanCurrent2.0.

Sea Surface Height Anomaly along ground-tracks of satellite altimeters

We use the [last 10 day's data] from [Jason-1], [Jason-2], [Cryosat-2], [SARAL] and [Envisat (until April 2012)] along with tidegauges (see below) to make maps of sea surface height anomaly for the Australasian region. These altimetry data are now sourced from the NOAA Laboratory for Satellite Altimetry via the Radar Altimeter Database System (RADS). In the plots linked above, some data points (sometimes whole tracks) are outlined in magenta, signifying that they have been rejected by our automatic quality control. At present this includes the very-most recent days' data from some satellites because a sufficiently-accurate estimate of the satellite's orbit is not available. The switch to RADS has allowed us to make use of newer versions of some of the quantities that need to be estimated in order to calculate sea surface height anomaly from radar range. This has resulted in closer agreement between the satellites, and a reduction of the combined estimate of sea surface height anomaly (particularly in the tropical west Pacific, by 0.1m), bringing the satellite-based estimate into closer agreement with the Argo estimates of steric anomaly. (This result needs further investigation. More information will be provided in the technical details section when available.)

Maps made prior to 9 December 2011 used data from individual sources: Envisat IGDR and GDR from ESA, Topex/Poseidon, Jason-1 and Jason-2 IGDR and GDR from AVISO and/or Physical Oceanography DAAC at NASA Jet Propulsion Laboratory , and GFO NGDR-Ms and GDRs from NOAA/LSA. We also used the low-latency NRTSSHA product for Jason-1 and Envisat generated by the Orbiter and Radio Metric Systems Group at JPL.

Australian National Moorings Network

Northern Australian shelf moorings (AIMS site).
National Reference Stations (CSIRO site).

Sea Surface Height Anomaly from tidegauges

To be written. Links:
National Tidal Centre
Queensland EPA
Manly Hydraulics Laboratory
WA Department of Transport

Surface Drifting buoys

Drifting Buoy Data Assembly Center
Data product intercomparisons (work-in-progress)
CSIRO 3-day composite and IMOS L3S_3day (day-only and/or night-only averages). The latter will replace the former as the source data for the larger-scale maps shown on this website.
[SW] [GAB d] [GAB n] [GAB] [SE]

Argo

The latest Argo data are downloaded daily from the ARGO GDAC FTP site.

[Australian Argo facility] [Australian Argo real-time processing] [Argo Australia delayed-mode processing]
[Argo Information Centre] [Argo home page]

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