About the sea surface temperature timeseries graphs

Analyses available

Sea Surface Temperature (SST) timeseries are available from 1900 for a number of regions around Australia. These timeseries include ocean surface temperatures only and do not include any land surface temperatures.

Note that sea surface temperature timeseries are presented as anomalies or departures from the 1961-1990 average because temperature anomalies tend to be more consistent throughout wide areas than actual temperatures. 1961 to 1990 is the current international standard period for the calculation of climate averages.

Mean sea surface temperature values are provided for a boxed region around Australia (from 4°S to 46°S and from 94°E to 174°E), as well as for six regions within this box: the Northern Tropics (4°S–22°S, 94°E–174°E), the Southern Region (30°S–46°S, 94°E–174°E), the Southwest Region (22°S–46°S, 94°E–116°E), the Northwest Region (4°S–22°S, 94°E–130°E), the Coral Sea (4°S–26°S, 142°E–174°E) and the Tasman Sea (26°S–46°S, 150°E–174°E). Values are also provided for the Great Barrier Reef (see below for details).

These regions are the same as those used to provide trend maps on these pages.

Regions around Australia used in sea surface temperature timeseries

Timeseries are determined for the seven regions shown above

The above areas have been chosen for analysis since they are large enough to contain a meaningful climatology and not be influenced by data and interpolation errors. At the same time, these areas are small enough to provide a meaningful representation of regional climate influences around the Australian continent.

Great Barrier Reef

In addition to the larger boxed areas shown above, timeseries are also produced for the Great Barrier Reef. This is calculated from the average of nine grid points that are in or close to the Great Barrier Reef Marine Park. Only nine points can be used because the underlying data is on a relatively coarse grid, of 2° (about 220 km) resolution. This also means that small scale features may not be fully resolved.

Map of the Queensland coast showing the Great Barrier Reef and the nine grid points used for the Great Barrier Reef timeseries

The nine grid points used for the Great Barrier Reef timeseries

Data used

The sea surface temperature timeseries are calculated from the NOAA Extended Reconstructed Sea Surface Temperature Version 4 (ERSST v4) data provided by the NOAA/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.esrl.noaa.gov/psd/. A full description of the ERSST v4 data can be found in Huang et al., (2015) and Liu et al., (2015).

Please note that any use of the data analysed on these web pages should be acknowledged to the Bureau of Meteorology. Apart from the purposes of study, research, criticism and review, no part of these data may be reproduced, or redistributed for any commercial purposes, or distributed to a third party for such purpose, without written permission from the Director of Meteorology.

The actual data values used to produce each graph are available via the "Raw dataset" link. The format for these data is:

    <start year><start month><end year><end month>   <mean temperature anomaly (°C)>

The "Sorted dataset" link provides the timeseries as a sorted list in order to place recent values in historical context.

Further information

Huang, B., V.F. Banzon, E. Freeman, J. Lawrimore, W. Liu, T.C. Peterson, T.M. Smith, P.W. Thorne, S.D. Woodruff, and H.-M. Zhang, 2015: Extended Reconstructed Sea Surface Temperature version 4 (ERSST.v4): Part I. Upgrades and intercomparisons. Journal of Climate 28:3, 911-930 doi:10.1175/JCLI-D-14-00006.1

Liu, W., B. Huang, P.W. Thorne, V.F. Banzon, H.-M. Zhang, E. Freeman, J. Lawrimore, T.C. Peterson, T.M. Smith, and S.D. Woodruff, 2015: Extended Reconstructed Sea Surface Temperature version 4 (ERSST.v4): Part II. Parametric and structural uncertainty estimations. Journal of Climate 28:3, 931-951 doi:10.1175/JCLI-D-14-00007.1

Great Barrier Reef features and park boundary spatial data provided by the Spatial Data Centre of the Great Barrier Reef Marine Park Authority. For more information or further spatial data, contact gis@gbrmpa.gov.au