What is the new Atlas?
The Sea Surface Temperature Atlas of the Australian Regional Seas (SSTAARS) covers the seasonal variability and trends around Australasia by making use of 25 years of Advanced Very High Resolution Radiometer (AVHRR) data from NOAA Polar Orbiting Environmental Satellites, received by six Australian and two Antarctic reception stations, to construct a detailed climatology of sea surface temperature (SST) at 20 cm depth around Australasia.
Data processing - technical detail
The data have been processed following international GHRSST protocols to help reduce instrument bias using in situ data, with only night-time nearly cloud-free data used to reduce diurnal bias and cloud contamination. A pixel-wise climatology (with four annual sinusoids) and linear trend are fit to the data using a robust technique and monthly non-seasonal percentiles derived. The resulting atlas has a spatial resolution of ~2km and thus reveals unprecedented detail of regional oceanographic phenomena, including-
- tidally-driven entrainment cooling over shelves and reef flats,
- wind-driven upwelling,
- shelf winter water fronts,
- cold river plumes,
- the footprint of the seasonal boundary currrent flows, and
- standing mesoscale features in the major offshore currents.
The atlas (and associated statistics) will provide a benchmark for high-resolution ocean modellers and be a resource for ecosystem studies where temperatures, and their extremes, impact on ocean chemistry, species ranges and distribution.