2016 SoE Marine Chapter - Pressures - Climate Change - Ocean currents and eddies

Brief description

The Marine chapter of the 2016 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "Pressures on the marine environment associated with climate change - ocean currents and eddies". The full Expert Assessment, including figures and tables (where provided), is attached to this record. Where available, the Data Stream(s) used to generate this Expert Assessment are accessible through the "On-line Resources" section of this record. ---------------------------------------- DESCRIPTION OF THE PRESSURE The dominant Australian boundary currents are the; East Australian Current (EAC), Indonesian Throughflow (ITF) and Leeuwin Current (LC). The EAC is the western boundary current system of the South Pacific. In the Australian region, it redistributes heat between ocean and atmosphere and the tropics and mid-latitudes. The ITF, a major component of the global ocean circulation, moves water between the Pacific and Indian Oceans. It strongly influences Australian climate and seas off Western Australia. The LC flows southwards off Western Australia redistributing Indian Ocean heat to the mid-latitudes. This differs from the cooler, equatorward flowing currents found along other eastern ocean boundaries. DATA STREAM(S) USED IN EXPERT ASSESSMENT The assessment is based on the results of analysis published in peer reviewed papers. Details of the specific data sets used to generate this assessment have not been provided. ---------------------------------------- 2016 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • Assessment grade: High impact. Boundary current strength is strongly linked to major climate modes – ENSO, IOD and SAM- whose variability are predicted to increase with climate change. • Assessment trend: Deteriorating. Increasing variability of boundary current strength and heat, freshwater, and nutrient transport, will impact coastal circulation, extreme marine conditions, and the marine ecosystem. • Confidence grade: • Confidence trend: Adequate high-quality evidence or high level of consensus. Observations and models agree that modes of climate variability will be impacted by continued climate change. ---------------------------------------- CHANGES SINCE 2011 SOE ASSESSMENT Grade and trends are somewhat comparable to the 2011 assessment.

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Statement: QUALITY OF DATA USED IN THE ASSESSMENT High quality but limited length of time-series.

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Purpose
To describe the pressures on the marine environment associated with climate change and ocean currents and eddies for use in the Marine chapter of the 2016 State of the Environment report.