The coastal zone is arguably the most difficult geographical region to capture as data because of its dynamic nature. Yet, coastal geomorphology is fundamental data required in studies of the potential impacts of climate change. Anthropogenic and natural structural features are commonly mapped individually, with their inherent specific purposes and constraints, and subsequently overlain to provide map products. This coastal geomorphic mapping project centered on a major coastal metropolitan area between Lake Illawarra and Newcastle, NSW, has in contrast classified both anthropogenic and natural geomorphological features within the one dataset to improve inundation modelling. Desktop mapping was undertaken using the Australian National Coastal Geomorphic (Polygon) Classification being developed by Geoscience Australia and supported by the Department of Climate Change. Polygons were identified from 50cm and 1m aerial imagery. These data were utilized in parallel with previous maps including for example 1:25K Quaternary surface geology, acid sulphate soil risk maps as well as 1:100K bedrock geology polygon maps. Polygons were created to capture data from the inner shelf/subtidal zone to the 10 m contour and include fluvial environments because of the probability of marine inundation of freshwater zones. Field validation was done as each desktop mapping section was near completion. This map has innovatively incorporated anthropogenic structures as geomorphological features because we are concerned with the present and future geomorphic function rather than the past. Upon completion it will form part of the National Coastal Geomorphic Map of Australia, also being developed by Geoscience Australia and utilized in conjunction with Smartline.

Geoscience Australia conducted a survey of benthic nutrient fluxes in Smiths Lake , during February 2003, to gather baseline data for the ongoing management of the waterway by the Great Lakes Council. The objectives were to: 1. measure the nutrient (and other metabolite) fluxes across the sediment-water interface; 2. assess the trophic condition of the two selected sites in Smiths Lake; and 3. describe key processes controlling the nutrient fluxes across the sediment-water interface at each of the two sites. The site in the larger western basin (SL2) had a higher carbon loading than the site in the smaller eastern basin (SL1). As a result, denitrification efficiencies have been reduces and more nitrogen retained in the system. Given the long residence time of the water in Smiths Lake, there is a threat of deteriorating water quality if nutrient inputs from the catchment are increased.

A collaborative field trial of the Quester-Tangent View Series 5 single beam acoustic benthic mapping system was recently conducted in Wallis Lake by Geoscience Australia and Quester Tangent Corporation. The survey involved acquisition of the acoustic backscatter data from the northern channels and basins of Wallis Lake. Quester-Tangent software (IMPACT v3) was used to classify acoustic echograms that returned from the lake bottom into statistically different acoustic classes, using principal components analysis. Six acoustically different substrate types were identified in the Wallis Lake survey area. Ground-truthing was undertaken to identify the sedimentological and biological features of the lake floor that influenced the shape of the return echograms. For each sample, measurements were made of grain size, wet bulk density, total organic carbon, CaCO3 content, and mass of coarse fraction (mainly shell) material. Statistical cluster analysis and multi-dimensional scaling were utilised to identify any physical similarities between groups of ground-truthing sites. The analysis revealed four distinct and mappable substrate types in the study area. The degree of association between acoustic classes and measured sediment parameters was also quantified. Cluster and MDS analysis revealed that, based on the parameters measured, the six acoustic classes were not uniquely linked to the sediment groups, suggesting that factors other than the sediment parameters alone are influencing the acoustic signal. The spatial interpretation of the Wallis Lake Quester-Tangent data represents the first quantification of non-seagrass habitats in the deeper areas of the lake, and provides a useful indicatior of benthic habitat diversity and abundance. For future studies, a more quantitative measure of faunal burrow size and density, and also other sedimentary bedforms, is recommended.

The Fitzroy catchment is the largest Queensland catchment discharging to the Great Barrier Reef (GBR) lagoon. Sediments and nutrients together with anthropogenic pollutants originating upstream in the catchment are discharged from the Fitzroy River via the Fitzroy Estuary (FE) and ultimately into Keppel Bay (KB). The estuary and the bay act as natural chemical reactors where the materials delivered undergo chemical and physical transformations before some are deposited and stored in the growing deltaic and beach areas, with the remainder transported eastward to the southern zone of the GBR lagoon.

Geoscience Australia has completed the first phase of an areal map of Australia's coastal geomorphological units. Utilising pre-existing GIS datasets procured from local, state and federal government agencies, this national scale map conforms to a coastal geomorphology classification scheme developed at Geoscience Australia. Phase one consists of a geodatabase containing a series of state wide feature datasets that have been reclassified into the national coastal geomorphology classification scheme.

Microalgal blooms are one of the most visible responses to anthropogenic nutrient loadings in coastal ecosystems. However, differentiating sources of nutrients causing blooms remains a challenge. The response of phytoplankton and benthic microalgae (BMA) to nutrient loads was compared across tidal creeks with and without secondary treated sewage in a tropical estuary. Concentrations of the sewage marker, coprostanol, were higher near sewage discharge points and decreased downstream. This was commensurate with a decline in nitrogen and phosphorus concentrations suggesting that sewage was the main source of nitrogen and phosphorus. Primary productivity in the water column was limited by nitrogen availability in absence of sewage, with nitrogen saturation in the presence of sewage. Phytoplankton primary productivity rates and chlorophyll a concentrations increased in response to sewage, and there was a greater response than for BMA. There was no evidence of a change in algal pigment proportions within the phytoplankton or BMA communities. This study highlights the scale and type of response of algal communities to sewage nutrients in situ.

Approximately 85% of Australia's population and much of its critical infrastructure is focused around the coastal zone. Continued migration to the coast and increasing coastal development creates challenges for coastal management and planning. It is anticipated that climate change will exacerbate these challenges in the coming decades through rising sea levels and more intense and frequent storms. These impacts will lead to increased risk of inundation, storm surge and coastal erosion which will damage beaches, property and infrastructure along susceptible shorelines and low-lying coastal areas and adversely affect a significant number of Australian coastal communities. The Australian Government's Framework for a National Cooperative Approach to Integrated Coastal Zone Management identified a need to 'build a national picture of coastal zone areas that are particularly vulnerable to climate change impacts to better understand the risks and interactions with other stressors in the coastal zone'. Decision-makers at all government levels need access to information to assist development and planning decisions and to identify valuable human and natural assets that require protection. Further to this aim, Geoscience Australia (GA) is assisting the Department of Climate Change to develop a 'first pass' National Coastal Vulnerability Assessment. This is providing fundamental information that will support decision-makers by identifying areas in Australia's coastal zone where potential impacts may be rated as high, medium and low. Potential climate change impacts have been assessed for cyclonic winds and coastal inundation from a combination of sea-level rise and storm surge scenarios.

Coral reefs occur in shallow water with sea surface temperatures (SST) greater than 18ºC, extending beyond the tropics where warm currents enable their establishment [Hopley et al., 2007]. The southernmost reef in the Pacific Ocean occurs at Lord Howe Island (31° 30°S), fringing 6 km of the western margin of the island, with isolated reef patches on the north, west and eastern sides. The island is a Miocene volcanic remnant on the western flank of the Lord Howe Rise (foundered continental crust) formed of basaltic cliffs rising to 875 m, flanked by Quaternary eolianites [McDougall et al., 1981]. The reefs support 50-60 species of scleractinian corals, whose rates of growth are only slightly slower than in more tropical locations [Harriott and Banks, 2002]. However, carbonate sediments on the surrounding shelf are dominated by temperate biota, such as foraminifera and algal rhodoliths [Kennedy et al., 2002]. Prominent in mid shelf is a broad ridge-like feature that rises from water depths of 30-50 m, which we considered to be a relict coral reef that formerly encircled the island [Woodroffe et al., 2005, 2006]. This paper describes results of sonar swath mapping to determine the extent of the reef, and coring and dating that establishes its age and demise.

A digital relief model (DRM) of the Swan Coastal Plain and Rottnest Shelf (7400 km2) was built with a range of topographic and high-resolution bathymetric datasets, gridded to a 50 m cell size. The DRM enabled the delineation of relict coastal landforms, benthic habitats and development of a regional morphostratigraphic framework. Well-defined features include: 1. Limestone ridges on the coastal plain that sit subparallel to the modern shoreline - these are coastal barriers deposited during Quaternary interglacial periods of high sea level; 2. Rocky reefs on the inner shelf that rise up to 10 m above the adjacent seafloor, remnants of coastal dune barriers that formed when sea level was 20 to 30 m lower than present, and; 3. A discontinuous ridge 3 to 10 m thick along the outer shelf - a relict coastal barrier that formed when sea level was around 60 m lower than present. The DRM provides a useful regional perspective of the distribution and form of these extensive reefs.

The Australian Government, through the Department of Climate Change and Energy Efficiency, recognises the need for information that allows communities to decide on a strategy for climate change adaptation. A first pass national assessment of vulnerability to Australia's coast identified that considerable sections of the coast could be impacted by sea level rise. This assessment however, did not provide sufficient detail to allow adaptation planning at a local level. Accounting for sea level rise in planning procedures requires knowledge of the future coastline, which is still lacking. Modelling the coastline given sea level rise is complex, however. Erosion will alter the shores in varied ways around Australia's coastline, and extreme events will inundate areas that currently appear to be well above the projected sea level. Moreover, the current planning practice of designating zones with acceptable inundation risk is no longer practical when considering climate change, as this is likely to remain uncertain for some time. Geoscience Australia, with support from the DCCEE, has now conducted a more detailed study for a local area in Western Australia that was identified to be at high risk in the national assessment. The aim of the project was to develop a localised approach so that information could be developed to support adaptation to climate change in planning decisions at the community level. The approach included modelling a historical tropical cyclone and its associated storm surge for a range of sea level rise scenarios. The approach also included a shoreline translation model that forecast changes in coastal sediment transport. Inundation footprints were created and integrated with Geoscience Australia's national exposure information system, NEXIS, to develop impact assessments on building assets, roads and railways. Studies such as this can be a first step towards enabling the planning process to adapt to increased risk.