Coastal impacts

Over recent years, there have been significant advances in our knowledge and understanding of the expected impacts of climate change on coastal areas. To assist communities to plan for and adapt to these impacts, the Tasmanian Government has developed guidance for land use planning and building in coastal areas, including sea level rise planning allowances and coastal hazard maps.

Understanding coastal hazards

The coast is a dynamic system, shaped by wave, wind and tidal movements. These processes, which are influenced by weather patterns, seasonal variations and projected climate change, can have a temporary or permanent influence on the coastline.

When their impacts, such as erosion, inundation and storm surge, threaten to damage public and private assets and/or natural values, these processes are described as hazards.

The majority of Tasmania’s population centres and major industries are located within one kilometre of the State’s nearly 6,400 kilometres of coastline.

Only a few settled areas of Tasmania’s coast are currently considered to be at high risk of coastal hazards. However, as sea levels rise and coastal processes are influenced by climate change, the number and extent of high-risk areas is predicted to increase.

Sea level rise planning allowances

Sea level rise planning allowances help to ensure consistency and certainty in how planners, developers,  property owners and managers take into account sea level rise in any new coastal developments.

In 2016 the Tasmanian Government engaged CSIRO to provide updated sea level rise planning allowances for the State. The updated allowances are based on the sea level rise projections provided in the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5) and are based on the high emissions scenario RCP8.5.

From the CSIRO work, Tasmania now has sea level rise projections and planning allowances for each coastal municipality in the State, as well as statewide averages for 2050 and 2100 (both relative to 2010 sea levels).

The sea level rise planning allowances for each coastal municipality can be found in this table: Tasmanian Local Council Sea Level Rise Planning Allowances (PDF).

More information on the sea level rise projections for Tasmania and coastal municipalities, as well as the methodology behind the projections, is detailed in the CSIRO report Sea-Level Rise and Allowances for Tasmania based on the IPCC AR5 (PDF).

Coastal inundation and erosion maps

The Tasmanian Government has developed coastal inundation and erosion maps that show how sea level rise and major storm events are projected to affect Tasmania's coastline. These maps will be important inputs into the planning code for coastal hazards, which will be implemented through the statewide planning scheme being developed as part of the Government’s planning reforms.

The coastal inundation and erosion map layers can be viewed online through the Land Information System Tasmania. Use the LISTmap function and select the 'Coastal Vulnerability' category from the available layers. The layers in this category will only be visible when zoomed in to less than 1:20000.

More information can be found at the Office of Security and Emergency Management website.

Projected changes

Climate Futures for Tasmania reports

• Extreme Events Technical Report – Summary (PDF)
• Extreme Events Technical Report – Full report (PDF)
• Extreme Tide and Sea-Level Events Technical Report – Full Report (PDF)
• Severe Wind Hazard and Risk Technical Report – Full Report (PDF)

Resources

Light Detection and Ranging Dataset

Light Detection and Ranging (LiDAR) is a remote sensing technology that measures distance by illuminating a target with a laser and analysing the reflected light, enabling a high resolution Digital Elevation Model (DEM) to be generated. Recently, a number of LiDAR datasets have been produced to generate DEMs to map inundation areas and coastal morphology (the origin of coastal features and how they have been shaped).

In November 2008, the Climate Futures for Tasmania (CFT) project delivered Tasmania’s first LiDAR dataset for coastal areas that may be vulnerable to inundation. Further information about the CFT LiDAR dataset is available in the LiDAR factsheet (PDF). Geoscience Australia then recaptured many of the CFT LiDAR dataset areas to build a coastal flooding visualisation tool (VisTool). This recapture corrected known errors in the initial CFT LiDAR dataset. VisTool helps identify low-lying areas that are vulnerable to sea level rise.

In 2014, the Tasmanian Government’s Department of Premier and Cabinet (DPAC) procured an additional LiDAR dataset for coastal settlements not included in the CFT project, or in Geoscience Australia's LiDAR datasets, to develop higher resolution coastal hazard maps for those areas. The DPAC Coastal LiDAR dataset, and other LiDAR datasets, are available by contacting listhelp@dpipwe.tas.gov.au or listdatasales@dpipwe.tas.gov.au.

Natural Systems Resilient to Climate Change Project

The Tasmanian Department of Primary Industries, Parks, Water and Environment has assessed the potential impacts of climate change on Tasmania's natural values. The Vulnerability of Tasmania's Natural Environment to Climate Change (PDF) report will help government and the community better understand the risks of climate change to the natural environment in order to make informed planning and management decisions.