Time Series

1

Physical and Chemical Environment

Report Icons_Section 1 copy

The Physical and chemical environment theme consists of six time series that focus on large-scale changes and variability of Australia’s oceanic environment

Key Findings

Time series of the physical environment (1.1) show steady warming of Australia’s oceans over the last century, with some regional variation. Regional variation is strongly influenced by the major ocean currents that flow around the Australian continent (see boxed text).

Warming has been fastest in the south, particularly in the South East and Temperate East bioregions. High variability between years, called interannual variability, is also observed (1.2, 1.3, 1.4). This can be related to the major modes of seasonal climate variability impacting the Australian region (see boxed text). Consistent with global climate models, seasonal, high-temperature extremes called ‘marine heatwaves’ can now be observed.  Marine heatwaves appear to be increasing in frequency and intensity, with implications for marine ecosystems (1.4, 2.6, 4.2).

Bringing these time series together enables investigation of connections between the physical environment, chemical environment, and biological productivity.

Along with rising temperature, increasing acidification of the ocean is observable at a global scale. Time series of chemical variables within the Australian marine environment (1.6) show large decreases in pH of seawater and in concentration of dissolved carbonate ions. These are the internationally accepted measures of ocean acidification. Regional data show interannual variability driven by the combination of seasonal climate and boundary currents. There is no evidence of decline in the abundance of calcifying organisms over the last decade (4.4).

Time Series

Citing the Report

Richardson A.J, Eriksen R, Moltmann T, Hodgson-Johnston I, Wallis J.R. (2020). State and Trends of Australia’s Ocean Report, Integrated Marine Observing System (IMOS).

IMOS_logo-stacked-reversed-01

The State and Trends of Australia's Ocean Report was supported by IMOS. IMOS gratefully acknowledges the additional support provided by the Commonwealth Scientific and Industrial Research Organisation (CSIRO).

The State and Trends of Australia's Ocean website is maintained by IMOS.

 

NCRIS-PROVIDER-REV

Australia’s Integrated Marine Observing System (IMOS) is enabled by the National Collaborative Research Infrastructure Strategy (NCRIS). It is operated by a consortium of institutions as an unincorporated joint venture, with the University of Tasmania as Lead Agent.

Disclaimer:

You accept all risks and responsibility for losses, damages, costs and other consequences resulting directly or indirectly from using this site and any information or material available from it. While the Integrated Marine Observing System (IMOS) has taken reasonable steps to ensure that the information on this website and related publication is correct, it provides no warranty or guarantee that information provided by the authors is accurate, complete or up-to-date. IMOS does not accept any responsibility or liability for any actions taken as a result of, or in reliance on, information on its website or publication. Users should check with the originating authors to confirm the accuracy of the information before taking any action in reliance on that information.

If you believe any information on this website or in the related publication is inaccurate, out of date or misleading, please bring it to our attention by contacting the authors directly or emailing us at IMOS@imos.org.au


Images and Information:

All information on this website remains the property of those who authored it. All images on this website are licensed through Adobe Stock, Shutterstock, or have permission from the original owner.