Every five years the Australian Government conducts a comprehensive review of the state of the Australian environment. National State of the Environment (SoE) reports provide information about environmental and heritage conditions, trends and pressures for the Australian continent, surrounding seas and Australia's external territories. SoE 2016 builds upon the 2011 approach by showing changes over time across the key areas of the environment, including atmosphere, inland waters, land, marine environment, Antarctic environment, biodiversity, heritage, built environment and coasts. This parent metadata record links to all Expert Assessments and associated Data Streams (where available) that have contribute to the Marine chapter of the 2016 State of the Environment report.

The Marine chapter of the 2021 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "Management Effectiveness of Climate and system variability and climate change". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Climate and system variability and climate change" BACKGROUND Climate variability, extremes and change affect Australia’s oceans, ecosystems and users of marine ecosystem services, with impacts that include changes in species distribution and abundance, disease outbreaks (e.g. corals, shellfish), and shifts in community composition. Managers of these marine ecosystem services variously respond to short and long-term impacts on a range of temporal and spatial scales. This assessment reports on the effectiveness of regional and local management responses to short-term climate variability, including extreme events, and long-term anthropogenic climate change impacts in Australia’s oceans. Increasing frequency and/or intensity of extreme events (e.g. cyclones and storm surge, marine heatwaves (flood plumes covered in Coasts chapter)), and long-term change in winds, ocean temperatures and pH (sea level is covered in Coasts chapter), can only be directly managed by global-scale emission reduction, carbon sequestration, and other climate system manipulations (geoengineering). The effectiveness of management of these manipulations is not covered in this assessment (e.g. Brent et al 2018, McDonald et al. 2019; McDonald et al. 2020; Gattuso et al 2021 for more information). DESCRIPTION OF THE APPROACH TO MANAGING THE PRESSURE Reactive and proactive management in response to climate pressures is influenced by the “agility” and risk appetite of the particular marine sector (Hodgkinson et al. 2014). Agility in both extractive (e.g. fishing, aquaculture, energy) and non-extractive (e.g. biodiversity, tourism) marine sectors is influenced by a range of factors related to innovation capacity (Figure 1). These are (1) degree to which system manipulation is possible (e.g. aquaculture vs wild fisheries), which can be related to the life cycle of the biological components (e.g. short-lived) or accessibility for manipulation (e.g. Alderman and Hobday 2017) and any associated infrastructure (moveable, restricted, flexible), (2) the regulatory environment (e.g. how flexible are management rules (Marshall et al. 2013)), (3) market forces (e.g. tourism season, consumer preference, competition), (4) value/profitability and relative size of marine industries, (5), leadership and key influencer attitudes, including political power and influence, (6) social expectations (e.g. expected to manage coral reefs, world heritage areas), and (7) visibility of impacts from extreme events or long term change (e.g. De’ath et al. 2012; Babcock et al. 2019). Currently most management responses are reactive (after an event) or implemented in real-time based on in situ or synoptic information. Proactive management, defined as forward planning ahead of an impact, can be informed by short-term forecasts and/or long-term climate projections (e.g. IPCC reports). Short-term forecasting approaches include using climatological patterns (i.e. manage conservatively using long term averages), analogue approaches (e.g. manage based on recent experience of an event), or dynamical forecasts (e.g. Hobday et al. 2018). Advance warnings at a range of time scales allows marine managers to implement strategies to minimise impacts of change. DATA STREAM(S) USED IN EXPERT ASSESSMENT Published papers and reports on climate variability. 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • Approach • Assessment grade: Partially effective Assessment trend: Improving Confidence grade: Adequate Confidence trend:

The Marine chapter of the 2021 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "Pressure of Climate and System Variability". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Pressure – Climate and System Variability" DESCRIPTION OF PRESSURE Climate and the marine environment vary on multiple temporal and spatial scales. This variability results in seasonal, inter-annual, decadal and longer changes to water temperature (e.g. Figure 1), rainfall patterns affecting ocean salinity, and surface winds, oceanic currents and tidal regimes which can influence the degree of vertical mixing through the water column. Collectively, these changes also propagate from the physical environment up the food chain. DATA STREAM(S) USED IN EXPERT ASSESSMENT Published papers and reports on climate variability. 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • 2021 • Assessment grade: High impact Assessment trend: Deteriorating Confidence grade: Adequate high quality evidence or high level of consensus Confidence trend: Adequate high quality evidence or high level of consensus Comparability: Comparable • 2016 • Assessment grade: Low impact Assessment trend: Unclear Confidence grade: Adequate high quality evidence or high level of consensus Confidence trend: Adequate high quality evidence or high level of consensus Comparability: Not previously assessed • 2011 • N/A CHANGES SINCE 2016 SOE ASSESSMENT The assessed state and trend of this pressure has increased from low/stable in 2016 to high/increasing for 2021 based on research documenting a trend for overall higher extremes of impacts associated with climate variability over the reporting period that is expected to continue.

The Marine chapter of the 2021 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "State and Trend of Water clarity (turbidity, transparency and colour)". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Water Clarity" DESCRIPTION OF PROCESS FOR EXPERT ASSESSMENT Marine environments (continental shelf and open ocean) are influenced by regional variation in climate, geomorphology and oceanography, all of which regulate the concentration and nature of the dissolved and particulate materials in seawater. These constituents collectively determine water quality. Australian marine waters are generally low in suspended sediments and colour resulting in relatively deep light penetration that allows pelagic primary producers (phytoplankton) to persist at depths greater than 100 m. Marine ecosystems are adapted to these conditions and therefore any deterioration in water quality (i.e., increased turbidity or decreased optical transparency) threatens key habitat-forming benthic primary producers such as kelps and seagrasses. In oceanic and outer continental shelf waters the major determinant of turbidity, transparency, and colour is the biomass of phytoplankton (Yentsch 1960), with phytoplankton growth largely being driven by the availability of dissolved nutrients. However, water transparency declines strongly toward shore due to increased sources of sediment, nutrients and greater phytoplankton biomass. The northern waters of Australia (Timor and Arafura Seas) have highest suspended sediment (lowest transparency) relative to southern waters, and those in the Coral Sea have greatest transparency (Secchi disk depth; Fig. 1). Water transparency is strongly seasonal, reaching a minimum in spring in the Temperate East and Southeast and in winter in the North, Northwest, Southwest and Coral Sea, due to growth of phytoplankton (as indicated by peaks in chlorophyll-a (Chl-a) concentration; Fig. 1; Thompson et al 2020). Tidal flows and waves contribute to turbidity, but extreme events such as tropical cyclones and storms can increase the level of suspended sediment by up to 3 orders of magnitude (x1000) due to both runoff and bottom disturbance by waves. In addition, tropical rivers in areas of high rainfall can deliver large amounts of sediment to the coastal zone, with plumes sometimes being quite extensive. DATA STREAM(S) USED IN EXPERT ASSESSMENT Water quality data was derived from two sources: i) IMOS National Reference Stations, sampled monthly ii) Globcolour, a time-series of ocean colour data merged from four satellite data sources: MERIS, MODIS, SeaWIFS. Globcolour data was accessed in a bounding box of 110-150 oE and -10:-45 oS over a time period that spanned the last 2 SOE periods, 2011 – 2020. The TSS product was only available from early 2016 onwards. For more information: https://www.globcolour.info/products_description.html Satellite sensors have the appropriate spatial (m to km) and temporal coverage (min to days), to assess water quality but require algorithms to convert satellite remote sensing reflectance into biogeochemical properties. While global algorithms are biased towards validation data collected predominantly in the northern hemisphere, satellite data remain the longest time-series with which to assess the status of marine water quality. These data are complemented by in-situ time series at IMOS National Reference Stations in a limited number of locations around Australia. 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • 2021 • Assessment grade: Good Assessment trend: Stable Confidence grade: Somewhat adequate Confidence trend: Adequate Comparability: Grade and trend comparable to 2016 assessment • 2016 • Assessment grade: Good Assessment

The Marine chapter of the 2021 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "Effectiveness of Management – Shipping (marine vessel activity)". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Effectiveness of Management - Shipping" DESCRIPTION OF THE APPROACH TO MANAGING THE PRESSURE The International Maritime Organization (IMO) is the United Nations agency responsible for safety, security and pollution prevention for international shipping. Australia is a signatory to key IMO conventions relating to maritime safety and environmental protection. The Australian Maritime Safety Authority (AMSA) is the federal agency responsible for maritime safety and environmental protection in Australian waters and works with other countries through the IMO. In Australia, Federal and State Governments work together in the control, risk reduction and risk response measures to manage shipping activity. The National Plan for Maritime Environmental Emergencies (AMSA 2020) sets out the cooperative arrangements in place to respond to maritime emergencies and incidents affecting the environment. Shipping in the Great Barrier Reef Region is well managed by AMSA, Maritime Safety Queensland and the Great Barrier Reef Marine Park Authority and guided by the North East Shipping Management Plan. Management protections and controls in place include REEFVTS vessel management system and designation as a Particularly Sensitive Sea Area (GBRMPA 2019). Interactions between marine fauna and shipping is largely addressed by the Department of Agriculture, Water and the Environment under the EPBC Act. AMSA provides guidance to the shipping industry on practices to avoid interactions between shipping and marine fauna. DATA STREAM(S) USED IN EXPERT ASSESSMENT no specific data streams used 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • Approach • Assessment grade: Very effective Assessment trend: Improving Confidence grade: Adequate Confidence trend: Adequate Comparability with 2016: Comparable • Outputs • Assessment grade: Effective Assessment trend: Improving Confidence grade: Adequate Confidence trend: Adequate Comparability with 2016: Comparable • Outcomes • Assessment grade: Effective Assessment trend: Improving Confidence grade: Adequate Confidence trend: Adequate Comparability with 2016: Comparable CHANGES SINCE 2016 SOE ASSESSMENT The assessment has not changed since 2016.

The Marine chapter of the 2021 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Case Study "Calls for ocean action: Australia's National Marine Plan within the context of international initiatives". A PDF of the full Case Study, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "CASE STUDY 2021 – Calls for ocean action: Australia's National Marine Plan within the context of international initiatives" DESCRIPTION OF THE CASE STUDY Prior to the publication of the 2016 State of the Environment report, Australia’s science community came together collectively to develop a ten-year plan to be carried out over the period 2015-2025 with a focus on identifying the science needed for addressing the largest sustainability challenges to Australia’s marine estate, and prioritising investment in order to fulfil Australia’s blue economy’s potential – the National Marine Science Plan (NMSP; Treloar et al. 2016; see also the case study in the 2016 State of the Environment report, Evans et al. 2017). A mid-term review of the NMSP has recently been completed and will be delivered in 2021, a year in which a number of relevant international initiatives are either launching or moving into implementation phases. These include the United Nations (UN) Decade of Ocean Science for Sustainable Development (IOC-UNESCO 2020; Pendleton et al. 2020; Singh et al. 2021), the UN Decade of Ecosystem Restoration (Young and Schwartz 2019; Fischer et al. 2020) and the High Level Panel for a Sustainable Ocean Economy (HLP 2020), all of which Australia has approved (via engagement in the relevant UN commissions and programs) or is directly engaged in with partner countries. These initiatives all recognise the life supporting role of the ocean and the need for action to ensure continued provision of the essential services the ocean provides to humanity. All recognise that transformations that provide solutions for the sustainable management of the ocean within national jurisdictions and safeguard areas beyond national jurisdiction are required to achieve this. Australia’s science community has the opportunity to align efforts and focus the implementation of the original recommendations of the NMSP and the emerging priorities identified in its mid-term review through these international initiatives. Many of the objectives set out under the UN Decades align directly with the recommendations of the NMSP and the commitments set out by the High Level Panel, particularly those focused on increasing understanding of ocean state and changes occurring in marine systems, reducing and responding to the impacts of climate change, ensuring sustainable management of Australia’s marine estate, supporting environmentally sustainable industries and enabling nature-based solutions to coastal development. A coordinated approach to providing the science to support decision making is central to the NMSP and is critical if Australia is to effectively contribute to the UN Decades and meet the commitments it has set itself under the High Level Panel. The National Marine Science Committee through its membership is well placed to drive the collaboration and coordination across disciplinary, sectoral and jurisdictional boundaries needed. The success of the UN Decades and the High Level Panel in achieving the transformation in ocean science that is needed to achieve the UN 2030 Agenda, the associated Sustainable Development Goals and a sustainable future ocean economy will depend on the joint efforts of researchers, engineers, and scholars from all disciplines working in close collaboration with stakeholders from all sectors of the community. DATA STREAM(S) USED IN CASE STUDY Synthesis of literature published and expert knowledge of the case study author.

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 Case Study "Towards a blueprint for monitoring and reporting on biodiversity in Australia’s oceans". The full Case Study, including figures and tables (where provided), is attached to this record. Where available, the Data Stream(s) used to generate this Case Study are accessible through the "On-line Resources" section of this record. DESCRIPTION OF THE FOCUS OF THE CASE STUDY Monitoring Australia’s Commonwealth Marine Area (CMA) is fundamental to understanding and reporting on how the ocean is changing in response to human pressures. The National Environmental Research Program Marine Biodiversity Hub, collaborated with the Australian Government Department of the Environment, to develop "Towards a blueprint..." to monitor and report on key ecological features in the CMA. "Towards a blueprint..." shows how Australia can expand its institutional capacity to meet the reporting needs of the Department of the Environment. It identifies existing data for areas where monitoring can begin, and assesses Australia’s capability to collect new monitoring data as a basis for decision making. Key Ecological Features (KEFs) are parts of the ocean identified in the Australian Government’s marine bioregional plans as highly valued for their importance to biodiversity or ecological function and integrity. They provide an important starting point for developing monitoring in the Commonwealth Marine Area. PRESSURES/ISSUES OF IMPORTANCE Fifty-four KEFs were identified in Commonwealth waters during marine planning processes. As the map of Australia illustrates (Figure 1), KEFs come in many shapes and sizes and Towards a blueprint divides them into six groups for reporting purposes. These are areas of enhanced pelagic productivity, canyons, deep seabeds, seamounts, shelf reefs and seabeds. While the oceanography of most KEF groups has been studied, the level of biological sampling varies. Areas of enhanced pelagic productivity are the best understood, and shelf seabeds and deep seabeds the least. The Bonney Coast Upwelling is one of nine enhanced pelagic productivity Key Ecological Features identified in Australia’s Commonwealth waters and provides a good example of how KEFs focus biodiversity monitoring. From November to May, the surface waters of the Bonney Coast are blown offshore by south-easterly winds and replaced by cold, nutrient-rich water. The sunlit nutrients fuel an explosion of phytoplankton that sustains hordes of marine life, from krill to blue whales. Understanding long-term changes to this biophysical system and distinguishing what is most likely to have caused any changes is the focus for monitoring. DATA STREAM(S) USED IN CASE STUDY Satellite observations of chlorophyll and derived net primary productivity estimates.

The Marine chapter of the 2021 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 - climate change - ocean currents and eddies". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Ocean Currents and Eddies" DESCRIPTION OF PRESSURE Australia’s shelf and coastal environment is largely controlled by the dominant Australian boundary currents including the East Australian Current (EAC), Indonesian Throughflow (ITF) and Leeuwin Current (LC), South Australian Current (SAC), Holloway Current (HC), and Zeehan Current (ZC) (Figure 1). The EAC is the western boundary current system of the South Pacific (Oke et a., 2019 and reference therein). In the Australian region, it redistributes heat and carbon between ocean and atmosphere, and between the tropics and mid-latitudes. The ITF, a major component of the global ocean circulation, moves water from the Pacific Ocean to the Indian Ocean (Sprintall et al., 2019 and reference therein). 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. 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • 2021 • Assessment grade: Very high impact Assessment trend: Deteriorating Confidence grade: Adequate Confidence trend: Deteriorating Comparability: Grade and trends are somewhat comparable to the 2016 assessment. • 2016 • Assessment grade: High impact Assessment trend: Deteriorating Confidence grade: Adequate Confidence trend: Deteriorating CHANGES SINCE 2016 SOE ASSESSMENT We have seen significant marine heatwaves and cold events since 2016. The duration and frequency of these events impact the marine ecosystem and industry.

The Marine chapter of the 2021 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 - shipping (marine vessel activity)". A PDF of the full Expert Assessment, including figures and tables (where provided) is downloadable in the "On-line Resources" section of this record as "EXPERT ASSESSMENT 2021 - Shipping (marine vessel activity)" DESCRIPTION OF PRESSURE Australia as an island relies heavily on shipping for transportation of its domestic freight and international imports and exports. Australia relies on sea transport for 99 per cent of its international trade (by volume) [1]. In the 2017/18 financial year approximately 1554 million tonnes of cargo were loaded (+21.9% increase since 2013/14), and 155 million tonnes discharged (+2.6%) at Australian wharves by 5859 vessels (+6.5%) that made 34,117 port calls (+18.8%) [2]. As well as commercial vessels, many smaller vessels use Australian waters and provide an important recreational pastime for many Australians. DATA STREAM(S) USED IN EXPERT ASSESSMENT not supplied 2021 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details] • 2021 • Assessment grade: Low impact Assessment trend: Deteriorating Confidence grade: Adequate Confidence trend: Limited Comparability: Grade and trend are comparable to the 2016 assessment • 2016 • Assessment grade: Low Assessment trend: Deteriorating Confidence grade: High level of consensus Confidence trend: High level of consensus Comparability: Comparable • 2011 • CHANGES SINCE 2016 SOE ASSESSMENT No change.