Rising seas threaten Australia's major airports – and it may be happening faster than we think

Australia’s major airports are under threat, but nobody seems to care.

Aussie airports under threat

Thomas Mortlock, Macquarie University; Andrew Gissing, Macquarie University; Ian Goodwin, Macquarie University, and Mingzhu Wang

Most major airports in Australia are located on reclaimed swamps, sitting only a few metres above the present-day sea level. And the risk of sea-level rise from climate change poses a greater threat to our airports than we’re prepared for.

In fact, some of the top climate scientists now believe global sea-level rise of over 2m by 2100 is likely under our current trajectory of high carbon emissions.

This makes Cairns (less than 3m above sea level), Sydney and Brisbane (under 4m) and Townsville and Hobart (both around under 5m) airports among the most vulnerable.

Antarctica’s ice sheets could be melting faster than we think. Tanya Patrick/CSIRO science image, CC BY

In the US, the National Oceanic and Atmospheric Administration (NOAA) has recommended that a global mean sea-level rise of up to 2.7m this century should be considered in coastal infrastructure planning.

This is two to three times greater than the upper limit of recommended sea-level rise projections applied in Australia.

But, generally, the amount of sea-level rise we can expect over the coming century is deeply uncertain. This is because ice-sheet retreat rates from global warming are unpredictable.

Given the significant disruption cost and deep uncertainty associated with the timing of sea-level rise, we must adopt a risk-based approach that considers extreme sea-level rise scenarios as part of coastal infrastructure planning.

Are we prepared?
As polar ocean waters warm, they can cause glaciers to melt from beneath, leading to more icebergs breaking off into the ocean and then a rapid rise in global sea levels. This has happened multiple times in the Earth’s past and, on some occasions, in a matter of decades.

The Intergovernmental Panel on Climate Change (IPCC) puts sea-level rise projections for Australia somewhere between 50 to 90cm by 2090, relative to the average sea level measured between 1986 to 2005. But the emerging science indicates that this may now be an underestimate.

Some studies suggest that if substantive glacial basins of the West Antarctic Ice Sheet were to collapse, it could contribute at least a further 2m to global sea levels.

Most Australian airports have conducted risk assessments for the IPCC projections.

In fact, there is no state-level policy that considers extreme sea-level rise for the most critical infrastructure, even though it is possible sea levels could exceed those recommended by the IPCC within the coming century.

And for airports, the planning implications are stark when you compare the current projection of less than a metre of sea-level rise and the potential of at least a 2m rise later this century.

Taking the most low-lying major airports in Australia as an example, our modelling suggests a collapse of the West Antarctic Ice Sheet would see their near complete inundation – without any adaptation in place.

For more elevated locations, coastal infrastructure may still be inoperable more frequently when the combined effect of storm surges, waves, elevated groundwater or river flooding are considered.

A $200 billion problem
Our airports and other forms of infrastructure near the coastline are critical to the Australian economy. The aviation industry has an estimated annual revenue of over A$43 billion, adding around A$16 billion to the economy in 2017.

While there are many uncertainties around the future cost of sea-level rise, a study by the Climate Council suggests sea-level rise of over a metre would put more than A$200 billion worth of Australian infrastructure at risk.

It is difficult to assign a probability and time frame to ice-sheet collapse, but scientific estimates are reducing that time frame to a century rather than a millennium.

Uncertainty generally comes with a cost, so proactive planning would make economic sense.

Adapting our most critical coastal assets while sea levels rapidly rise is not an option – mitigation infrastructure could take decades to construct and may be prohibitively expensive.

Given the deep uncertainties associated with the timing of ice-sheet collapse, we suggest airport and other critical coastal infrastructure be subjected to risk analysis for a 2-3m sea-level rise.The Conversation

Thomas Mortlock, Senior Risk Scientist, Risk Frontiers, Adjunct Fellow, Macquarie University; Andrew Gissing, General Manager, Risk Frontiers, Adjunct Fellow, Macquarie University; Ian Goodwin, Associate Professor, Macquarie University, and Mingzhu Wang, Senior Geospatial Scientist, Risk Frontiers, Adjunct Fellow, Macquarie University

This article is republished from The Conversation under a Creative Commons licence. Read the original article.

If you enjoy our content, don’t keep it to yourself. Share our free eNews with your friends and encourage them to sign up.

RELATED ARTICLES





    COMMENTS

    To make a comment, please register or login
    TREBOR
    15th Jun 2019
    7:47am
    Are they rising? For real?

    I thought this article would be about the amazingly failed private enterprise model for such ventures... as airports, roads, electricity, gas....
    TREBOR
    15th Jun 2019
    7:50am
    2m in two years? Why the amazing race to the top of sea level rise all of a sudden? Somebody better tell our major trading partners to chop their emissions instantly........ leading to a total collapse of the global economy (not a bad thing) and bring the world to the brink of oblivion through the endless run of future wars...
    Bakka
    15th Jun 2019
    8:12am
    Another one sided “Alarmist “ article ... no doubt the world is currently experiencing a warming cycle ...as it has in the past ...and given the increase in global population over the past 30 years you would expect some form of reaction . However all these contributors seem to be from the Doomsday Brigade... How about “ balancing “ the article with views from the other end of the spectrum.. That way we can all make up our mind in a more informed way.
    musicveg
    15th Jun 2019
    2:13pm
    What other end of the spectrum? What are your suggestions?
    BORIS
    15th Jun 2019
    8:28am
    Look at the sea level rises over the past 10,000 years since the last ice age of around 100 metres without any man made influences and we see things in perspective. By all means take steps to reduce pollution and clean up our act, but whatever we do, it will only have a small effect on global warming in the long run. Earth’s natural cycle of warming and cooling will be the determining factor.
    Long term planning should be focused on adjusting to naturally caused climate changes, rather than trying to fight against nature. Sea levels are going to rise dramatically (hundreds of meters) until the earth starts cooling again as part of the natural warming and cooling cycle and the human race race is going to have to adapt to suit.
    Airports and other infrastructure will need to take rising sea levels, as well as other changes, into account, but the change process is quite slow, and who knows, by 2100, with the advent of vertical take off aircraft, airport runways and the current concept of air transport could very well be redundant. Certainly the airports referred to will be due for replacement or upgrading anyway so why the concern?
    Of more importance is the location of towns and cities, and the need to abandon some of the low lying Pacific islands.
    In other words we should be planning to accomodate rising sea levels, and not imagining that we can avoid the event by reducing pollution. We must reduce pollution anyway, but it will have little effect on rising sea levels or global warming.
    GeorgeM
    15th Jun 2019
    4:22pm
    Good comments, including good common sense. Now, what happened to common sense for all these doomsday forecasters? The best the Govt can do is to cut the funding for such fake researchers with pre-committed bias as well as funding for the IPCC, and instead use the funds to reduce pollution of our environment especially where it affects people and farms.
    MICK
    15th Jun 2019
    8:44am
    If modelling proves correct then we will all suffer in many ways. Should many low lying coastal areas go under water then the wealthy owners of this real estate will, for the most part, get what it deserves because many of these people support the coal owned party and would also have held fossil fuel shares.
    Whilst the doubters will say 'no worries' and 'its all in the imagination of scientists' I'm willing to bet that the future plays out closer to predictions if not exactly spot on. And so the game goes on and the vested interests keep collecting their dividends. Too bad for their grandchildren for whom they care zip. Bring it on.
    TREBOR
    15th Jun 2019
    10:18am
    Hang on, Mick - I'm now in a low lying coastal area - hardly a wealthy owner.... I might look rich, but hey ....
    MICK
    15th Jun 2019
    7:36pm
    Waterfront property? Say no more.
    TREBOR
    15th Jun 2019
    7:47pm
    Resurrected swamp - I explained that to the ex by looking at the trees and the flat terrain... adios muchachos.. I'm going down with the ship....
    Couldabeen
    15th Jun 2019
    9:01am
    An alarmist article with no true scientific validity. Australian sea level monitoring going back over 150 years has shown no rising levels. Not even the 30cm predicted around 30 years ago.
    Think back about where our airports were 100 years ago. With the rate of technology changes, think about where they could be in 100 years. As there were none then, it is quite possible that our transport methods may evolve beyond them.
    Rail is a quite possible future method of large scale travel as it has rolled along in the back ground for over 150 years.
    This article carries a number of possibles and maybes requesting further studies. In other words "We don't know what we are talking about, so give us some more of your money so that we can pretend to carry out important work."
    TREBOR
    15th Jun 2019
    10:17am
    Rail lines - was discussing the difference between 1000 trucks headed up the highway and 2-3 engines in a train pushing out emissions - seems to me less emissions from the rail engines.... on the other hand, regional transport distribution hubs are a must for a restoration of rail lines .... like all such concepts - the time to act is NOW - not fifty years down the track (sic) when the cost of land etc becomes prohibitive.
    Eddy
    15th Jun 2019
    12:21pm
    Couldabeen, are you for real, 'no scientific validity'. What do you think CSIRO and US NOAA base their climate predictions on, sorcery. The scientific community are almost unanimous about the effects of climate change and what we need to do about it. While I am unqualified to assess their science I do accept it as more likely to be accurate than the biased opinions of vested interests. The old cry that all they want is more money is the sort of opinion that may condemn our great grandchildren and great-great grandchildren to problems we cannot even contemplate today. Views such as yours are merely postponing implementing effective action as it may inconvenient. Nevertheless I wholeheartedly endorse your thoughts on the use of rail transport.
    pedro the swift
    15th Jun 2019
    1:23pm
    Easy solution! Floating airports! But I doubt I will have to worry about airport flooding by sea level in my lifetime. More concern is the selling off of airports, power stations and other key infrastructure to foreign interests.
    My idea for Sydney's second airport was to put in the central NSW in Dubbo. Lots of land, central to Qld,Vic and SA and incentive to build a high speed rail link to all those capitals. But our gov. does not have any real foresight to for this country.
    Andy
    15th Jun 2019
    1:53pm
    the money people just dont give up next addition they be saying if you do this and that(billions of dollars) the airports can be saved these people always remind me of the 2000 computer crisis total joke old Bill is still laughing all the way to the bank
    musicveg
    15th Jun 2019
    2:17pm
    Amazing how there are more comments saying it is alarmist article than supporting it here, just goes to show who cares about supporting their polluting coal, oil and gas shares.
    You only have to go along any coast in Australia and there are many areas where sea walls are falling into the ocean, it is quite alarming, and I have never seen this before. What are we waiting for?
    B5YCK
    15th Jun 2019
    3:49pm
    "and I have never seen this before"
    How long have you been alive?
    Paddington
    15th Jun 2019
    3:23pm
    We might be small but we matter. We set an example. We help poorer countries do the right thing. We influence countries in our region in particular.
    The deniers need to ask themselves one question only, ‘Is it worth the risk?’ Of course it is not.
    Hawke, hopefully, from yesterday’s memorial might persuade this LNP government to finally do the right thing. They said they loved him, then listen up you climate change draggers.
    TREBOR
    15th Jun 2019
    7:48pm
    Tell it to the Chindians in their mad rush to production and heaps of power....
    Not a Bludger
    15th Jun 2019
    5:08pm
    What complete nonsense.
    Yet another scaremongering article from YLC based only on an opinion or two and no hard measurements.
    Greenie claptrap at its worst!
    BillF2
    15th Jun 2019
    5:33pm
    Have to agree with Couldabeen. When our weather forecasters with all their monitoring equipment cannot get it right more than a couple of days in advance, why should we believe some nerd who makes a computer model of what he thinks will happen in 80 years time? I think these people are on unprescribed medication. The greatest problem is that so many people believe them - which only goes to show the level of intelligence in government and educational institutions.
    TREBOR
    15th Jun 2019
    7:49pm
    There is intelligence in government and educational institutions? Well - you learn something new every day.
    Julian
    17th Jun 2019
    10:03am
    Here's an article titled the truth on global warming:

    https://m.youtube.com/watch?v=fA5sGtj7QKQ


    Join YOURLifeChoices, it’s free

    • Receive our daily enewsletter
    • Enter competitions
    • Comment on articles