Report assesses climate risks of sea level rise for Australia

A new report published by the Australian Government - Climate Change Risks to Australia's Coasts povides a risk assessment of climate change and rising sea level to Austrlian coastal communities. The report shows between 157,000 to 247,600 existing residential buildings will be at risk from sea inundation by 2100, under a sea-level rise scenario of 1.1 metres.

Related: Impacts of rising sea level a wake up call on climate change | Report

The report notes that "85 per cent of the population now live in the coastal region and it is of immense economic, social and environmental importance to the nation. All Australian state capital cities are located within the coastal zone, it is the conduit for our exports and imports, and much of the nation's commercial activities occur in coastal areas. Large numbers of Australians enjoy the recreational benefi ts the coast provides and it is home to a vast array of treasured environmental values that underpin essential ecosystem services."

The report used recent research, as presented at the Copenhagen climate congress in March 2009, of projected sea-level rise from 75 centimetres to 190 centimetres relative to 1990, with 110-120 centimetres the mid-range of the projection. Based on this research 1.1 metres was selected as a plausible value for sea-level rise for the risk
assessment in the report to 2100. It was noted that sea level is likely to continue to rise beyond 2100 and that sea-level rise projections will change as new research clarifies areas of uncertainty.

The occurence and severity of extreme weather events will increase "events that now happen every 10 years would happen about every 10 days in 2100. The current 1-in-100 year event could occur several times a year." says the report.

In launching the report Climate Change Minister Senator Penny Wong said "The science tells us our climate is changing faster than first projected and the impacts are likely to be more severe as sea-level rises and extreme storms and floods become more frequent. These changes are already happening and we cannot afford to ignore the findings of this report."

Port facilities around Australia will be effected, as will Sydney and Brisbane airports. At least 11 power plants/substations are located within 500m of the coastline. The report details that there is a large number of facilities within 200 metres and 500 metres of the coastline, potentially at risk under a changing climate. This includes a large number of hospitals, police, fire and ambulance stations very close to the coast. In an extreme weather event the functionality of these services may be compromised, resulting in significantly greater impacts than might otherwise occur and could result in deaths.

"Sea-level rise, more intense cyclones and ocean acidification will potentially increase the capital and operating costs of ports quite significantly by mid century,'' Senator Wong said. "A number of airports are also located in low-lying areas in the coastal zone, and are at risk of inundation in the coming century.''

The Torres Strait Islands, containing 17 Island communities with a total population of around 8,700 people, was assessed as extremely vulnerable to sea level rise. The report noted the IPCC finding that "Indigenous communities in the tropical north, home to about 87,000 Indigenous people, are also considered to be very vulnerable to the impacts of climate change. Such communities often live in isolated areas that are poorly resourced, and tend to have greater health issues and lower incomes than other communities."

"Every day we delay action on climate change, we increase the cost," Senator Wong said
"This report shows the need to reduce the carbon pollution that is causing climate change, which is why we are determined to pass the Carbon Pollution Reduction Scheme. It also shows that Australia must plan to adapt to the climate change we can't avoid."

The Government is in negotiations with the Liberal and National Parties to pass legislation for its Carbon Pollution Reduction Scheme (CPRS) to be reintroduced into the Senate in the coming week. This legislation will create a 'carbon market', with many free credits issued initially to major companies in carbon emission intensive industries, particularly coal and power industries.

Greens Deputy Leader Christine Milne commented "Despite these dire warnings we have a government intent on increasing the burning and export of coal and the logging and burning of our native forests for decades to come, knowing full well that this will result in the climate change impacts the government says it is concerned about."

"The absurdity of the situation is that the government's own emissions trading legislation to be debated in the Senate in the coming fortnight will do nothing to stop the outcomes outlined in today's report."

"The government should take the report on notice and redesign its emissions trading legislation to adopt strong targets to tackle climate change and end billions of dollars of handouts to the big polluters,"
Senator Milne said.

The release of the report was accompanied by the announcement by Senator Wong of the creation of a seven-member Coasts and Climate Change Council to be chaired by Professor Tim Flannery. Other members include: Ms Sam Mostyn - expert in sustainability and risk management; Mr Ron Clarke - Mayor of Gold Coast; Ms Paddi Creevey - Mayor of Mandurah; Professor Barbara Norman - Foundation Chair, Professor of Urban Planning, at University of Canberra; Professor Bruce Thom - President, Australian Coastal Society; and Geoff Lake - President, Australian Local Government Association.

The Council has been set the task of engaging with the community and stakeholders and advising the Government in the lead up to a Coastal Climate Change Forum, to be held in early 2010. This Forum will bring together all levels of government to develop a strategy for coastal adaptation.

The report was a first pass national assessment - one of the key actions identified in the National Climate Change Adaptation Framework endorsed by the Council of Australian Governments (COAG) in 2007.




Dr Andrew Ash, Director of the CSIRO Climate Adaptation Flagship, said "This report advances our understanding of coastal vulnerability through a scenario approach that quantifies the risks associated with climate change around Australia's vast coastline. The report makes sobering reading in the context of the risks to infrastructure alone. The report also helps to make the case for more urgent and proactive adaptation to reduce the risks posed by climate change through strategies such as planned avoidance."

Dr John Church, Principle Research Scientist in CSIRO Marine and Atmospheric Research and Leader of the Sea Level Rise Program at the Antarctic Climate and Ecosystem Cooperative Research Centre, commented "Sea-level rise will not stop in 2100 but continue for centuries. Without urgent, significant, and sustained mitigation, the concentration of greenhouse gases could cross a threshold during the 21st century leading to an ongoing decay of the Greenland Ice Sheet and a sea level rise of metres. "

"Sea-level rise is being and will be felt most acutely through extreme events. It is the combination of the gradually rising sea levels, interannual variability of sea level and extreme high sea levels experienced during storm surges that will have most impact. On both the west and east coast of Australia, there has already been an increase in the frequency of high sea levels by about a factor of three. By late in the 21st century, for many locations in Australia, the current 1 in 100 year event is likely to be occurring several times per year." said Dr Church

Professor Will Steffen, Executive Director of the Climate Institute at The Australian National University, said "Although there is much emphasis on the projections of sea-level rise by 2100, the sea won't stop rising by then. Given the great thermal inertia in the ocean and in the large polar ice sheets, we are already committed to a continually rising sea level for centuries to come".

Source: email from Australian Science Media Centre - 14 November 2009

Does the Dept of Climate Change have any actual measurements of CURRENT sea level rise on Australia's coastline? Here is an actual measurement showing Holland [which, being a country below sea level, has a vital interest in SLR] as having a current SLR of 9 cms per century. This amount, I understand, is similar to that of the east coast of Australia. This is about 8% of your prediction. I have contacted civil engineers in coastal cities to see if they are experiencing any observable and measurable SLR over recent decades and they say they are not. Not one that I found had raised the MSL benchmark. Is this prediction simply based on those same GCM predictions the IPCC uses that are failing to predict the warming [or non-warming] correctly or are you using other data? If and when they occur, we all need to be kept fully advised of the details used in assesing this huge potential problem and the incremental results thereof. Do you intend to report actual SLR that has occurred over recent decades and continue on a regular basis?

If this SLR is the result of human caused CO2 emissions [which you claim] and these same CO2 emissions have been increasing greatly in recent decades, [China has overtaken the US as the world's greatest CO2 emitter, eg.] then this should be showing up as an increased rate of SLR.
Why is this increased rate of SLR not happening?

The increased CO2 emissions are indeed a cause for concern. The increase in global temperatures will cause melting & increased mass loss from the Greenland & Antarctic ice sheets.

But these processes take time. By the time we start to see significant rises (~50cm or more) it will be too late to start thinking about fixing the problem.

Some projections are that it will take as much as a millennium for sea levels to stabilise, and by that time much of Greenland and possible large chunks of Antarctica will be either ice-free or covered by much, much thinner ice sheets.

Most reports of projected sea level rise of ~1m by the end of the century also gloss over the fact that most of the same scientists are saying it will keep on rising, by as much as 6-7 metres at least, but will take centuries to get there.
This article has some details on the expected effects on the Greenland icesheet.

It’s certainly very difficult for the many Australians who own a property on or near the water way to understand the risk to their asset from sea level rise.

Across Australia's six states, we have four different projected figures and no nationally consistent guide. This has left councils doing a some what piece-meal job in implementing development restrictions and certainly a great deal of uncertainty for home owners.

The liability for any loss to property sits firmly with the home owner, and it is their responsibility to understand the full risk to their asset. Not all properties will be impacted equally. Having a Climate Change Impact Assessment done on their property will highlight what development restrictions currently apply and may do so into the future, as well as the physical risks from flooding and erosion. It also provides some mitigation recommendations to perhaps reduce this risk.

Despite there being a large number of people who disagree with sea level rise (such as the previous annon poster), personal belief does not change the fact that the coastal property market is changing, and home owners need to be aware.

Heather Stevens
Climate Change Impact Assessments

Assessing the risk to property from sea level rise