EcoCheck: Australia’s Alps are cool, but the heat is on

Dick Williams, Charles Darwin University and James Camac

Our EcoCheck series takes the pulse of some of Australia’s most important ecosystems to find out if they’re in good health or on the wane.

Think of an Australian landscape and you’re unlikely to picture snow-capped mountains or alpine meadows. But that’s what you’ll find atop the peaks of the country’s southeastern corner.

The distribution of alpine and subalpine landscapes in Australia.
Author provided

Although relatively small – covering about 11,000 square kilometres or 0.15% of the continent – these alpine and subalpine ecosystems have outstanding natural value and provide billions of dollars’ worth of benefits to the nation each year.

They are in comparatively good health but are facing numerous threats. However, their health in decades and centuries to come will depend largely on how we deal with these threats now.

Australia’s main alpine and subalpine areas are the Snowy Mountains in New South Wales, the Bogong High Plains in Victoria, and central and southwestern Tasmania. They occur above about 1,400-1,500m on the mainland, and 700-1,000m in Tasmania.

Main Range, Kosciuszko National Park, NSW
Colin Totterdell

Although Australia’s mountains are relatively low by global standards (Mt Kosciuszko, the continent’s highest peak, rises only 2,228m above sea level), there is true treeless, alpine vegetation above the climatic treeline.

Treeless patches may also occur in the high subalpine zone, just below the treeline, typically on rolling high plains where accumulations of cold air or water prevent trees from establishing and growing.

The alpine climate is cold, wet, snowy and windy, with a short growing season. The soils are highly organic and can hold tremendous amounts of water. Alpine plants are short: mostly tussock-forming snow grasses, rosette-forming herbs such as snow daisies, and ground-hugging shrubs.

The dominant plant communities are grasslands, herbfields, heathlands and wetland complexes rich in peat moss (Sphagnum). The animals are mostly invertebrates such as moths, grasshoppers and ants.

Alpine wetland, rich in Sphagnum and other peat-forming plants, Bogong High Plains, Alpine National Park, Victoria
James Camac

The Australian Alps are hugely important for conservation, water production and recreation. Most alpine areas are within national parks and are home to many unique plants and animals.

There are about 700 native alpine plant species on the mainland, while some animal species are extremely rare – there are only about 2,000 mountain pygmy possums in the wild.

Major rivers – such as the Murray, the Murrumbidgee and the Snowy – begin in the Alps. Water from alpine catchments is worth A$9.6 billion a year to the Australian economy.

Millions of people visit every year to camp, walk, ski, ride and take in the scenery. The Alps are one of Tourism Australia’s “National Landscapes” and the local tourism industry is worth hundreds of millions of dollars annually.

Highly studied

The alps also have a rich history of scientific study, dating back to celebrated botanist Sir Ferdinand von Mueller in the 1850s. Pioneers of Australian alpine ecology, Alec Costin and Maisie Carr, established some of the earliest study sites. Research continues to this day and now includes international climate science projects such as the International Tundra Experiment and the Global Research Initiative in Alpine Environments.

Experimental plots established by Maisie Carr and John Turner in 1947 (photos taken in 1999). Aerial and close-up images both show the striking difference in the vegetation of the ungrazed plot compared with the grazed plot. Grazing ceased on the Bogong High Plains in 2003, and in Kosciuszko National Park in 1967.
Henrik Wahren

These scientific discoveries about alpine flora and fauna, and the factors that affect them, have directly informed land management practices.

We now know that high levels of vegetation cover are needed to protect alpine catchments; that livestock grazing damages alpine ecosystems; how to better implement cost-effective weed control; how to better manage small Mountain Pygmy Possum populations; and that large, infrequent fires do not necessarily cause “ecological disaster”.

Existing and emerging threats

Alas, the alps face multiple threats, including global warming, invasive species, disturbances such as fire, increasing pressure from human recreation, and unsound ideas about how to manage the high country.

The climate has already changed. Since 1979, average temperatures during the growing season on the Bogong High Plains have risen by 0.4℃, while precipitation has decreased by 6%. Since 1954, the depth and duration of the snowpack in the Kosciuszko region have declined.

Rising temperatures are a serious problem because the Australian Alps are relatively low mountains and the alpine species, already at their distributional limits, have nowhere else to go. Woody vegetation may increase – the treeline may rise and shrubs are likely to expand into grasslands and herb fields, which may make the landscape more prone to fire.

Mainland alpine ecosystems can regenerate after large fires. But Tasmania’s alpine vegetation is extremely fire-sensitive, and more frequent fire is likely to be detrimental to all alpine ecosystems.

The threat of livestock grazing to alpine ecosystems has all but ceased. However, feral animals and plants are a clear threat and will become more difficult to manage in the future without concerted action now.

Horse and deer numbers are increasing with alarming speed. These animals are occupying habitats well above the treeline. Many alien plant species have invaded the alps over the past half-century, a trend likely to be exacerbated by climate warming.

Feral horses in Pretty Valley, Bogong High Plains.
James Camac

We also need to be wary of maladaptive ideas and practices, particularly those concerning the putative benefits to the alps of large non-native grazing animals. We have variously been told that “alpine grazing reduces blazing” (it doesn’t); that grazing combined with burning has “actually prevented soil erosion” (it didn’t); and that a “sustainable, viable” feral horse population can “co-exist” with the alpine environment (surely an oxymoron). There may be strong cultural imperatives behind these propositions, but they have no basis in science.

Cattle grazing on the Bogong High Plains, days after the extensive 2003 fires. Australian alpine vegetation did not evolve with large, hard-hooved animals such as sheep and cattle. The combination of burning and grazing is known to damage alpine soils and vegetation.
Henrik Wahren

There is cause for hope, however. The Australian Alps are on the National Heritage List, which is protected by federal law.

There is also still time. The world is acting on climate change. Some species may adapt genetically, while some likely changes to vegetation may happen slowly. Scientists and land managers are working together to anticipate and manage change in the alps.

Change is inevitable, but with enough research, imagination and action, our high country will provide Australians with high-value environmental benefits for generations to come.

Are you a researcher who studies an iconic Australian ecosystem and would like to give it an EcoCheck? Get in touch.

Dick Williams, Adjunct Professorial Fellow, Research Institute for the Environment and Livelihoods, Charles Darwin University and James Camac, Postdoctoral Research Fellow

This article was originally published on The Conversation. Read the original article.

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PolicyCheck: Labor’s phased emissions trading scheme

Alan Pears, RMIT University

Welcome to PolicyCheck, a new form of political coverage that aims to make better sense of policies launched by the major parties in the lead up to the 2016 election. Here, The Conversation’s academic experts look at the history of policies, whether they have been tried in Australia before, and how likely they are to succeed.

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Labor has announced a six point climate change strategy, aimed at increasing renewable energy use, improving energy efficiency and transitioning away from old and inefficient coal power stations.

The policy includes a plan to reintroduce an emissions trading scheme for large emitters (over 25,000 tonnes annually), introduced over two phases.

How would it work?

Labor’s policy documents says that:

Phase one of the ETS will operate for two years, from 1 July 2018 until 30 June 2020 to align with the second (and final) commitment period of the Kyoto Protocol;

Phase two of the ETS will operate from 1 July 2020. Pollution levels will be capped and reduced over the course of the decade in line with Australia’s international commitments under the Paris agreement;

The broader ETS does not apply to the electricity sector (see separate fact sheet on Cleaner Power Generation); and

The scheme will allow business to work out the cheapest and most effective way to operate and will not involve taxpayers handing over billions of dollars to Australia’s large polluters.

Fairfax reported that

The cost up until 2020 would be about 3 cents per tonne of carbon for those industries exposed to foreign competition. For other firms, that cost will be about 30 cents a tonne.

The scheme design beyond 2020 would be worked out in the future, but would focus on meeting Australia’s international commitments.

A separate scheme for energy generators would start from 2018.

What’s the history behind the proposed scheme?

Climate policy has been a hot topic in Australian politics for over 25 years.

The Hawke government made a conditional commitment in 1992 to cut carbon emissions. In the mid-1990s, industry staved off a carbon pricing scheme under the Keating government by committing to a voluntary Greenhouse Challenge program.

John Howard’s 1997 pre-Kyoto Protocol statement, Safeguarding the Future, mapped out a number of response measures, intended to underpin Australia’s efforts to gain an easy target under the Kyoto Protocol.

Indeed, Australia got a Kyoto target of 8% above its 1990 emissions level, while the overall developed country goal was a 5% cut.

The Australian Greenhouse Office, set up after the Kyoto meeting, produced numerous reports and discussion papers exploring climate policy options, including various options for pricing emissions.

Former Prime Minister John Howard grudgingly proposed a cap and trade plan in 2007 on advice from senior bureaucrat Peter Shergold.

That scheme was meant to be up and running by about 2011, but plans were cut short by election of Labor’s Kevin Rudd as prime minister in 2007.

Rudd promised a strong commitment to climate action, and under his leadership, the Carbon Pollution Reduction Scheme was developed (it was basically an ETS). In 2010, today’s prime minister Malcolm Turnbull also preferred an ETS, even crossing the floor to support it.

This scheme was eventually rejected by the parliament because the Greens and many others considered it was too compromised to be effective. This was the beginning of the shambles that has surrounded Australian climate policy in recent years.

Julia Gillard replaced Rudd as Labor leader in the mid-2010 and worked closely with the Greens and other cross-benchers to develop the Clean Energy Future package. Part of that package was a plan to put a price on carbon.

The plan was to transition into a market-based emissions trading scheme in 2015, but the so-called carbon tax was axed by the Abbott government in 2014 (despite evidence it was effective in reducing emissions).

Australia’s present Direct Action policy has as its centrepiece the Emission Reduction Fund, which uses taxpayer funds to support a very limited number of emission reduction actions through an auction process.

The associated “safeguards” mechanism is yet to be finalised, but provides a possible basis for a future emissions trading scheme.

How is Labor’s “phased” ETS different to what they previously proposed?

Separating the electricity industry from the broader ETS allows transition to be managed more delicately, and reduces risk of criticism over the impact on electricity prices.

It will involve much lower carbon prices that will be more closely linked to international carbon prices. This leaves Labor open to criticism from many economists and advocates, who take the view that a much higher carbon price is an essential element of an effective climate response.

The low carbon price expected, and the heavy reliance on international permits will severely limit the amount of revenue from carbon pricing for some years. This denies the government a potential revenue source to fund other climate action.

Why has this issue been so fraught in the past?

Climate policy has been controversial in Australia since the early 1990s. Powerful industry groups have lobbied since then to limit climate action, and the issue has been framed as the economy versus a future, uncertain environmental impact.

This conflict was amplified by the Coalition under Tony Abbott, both in opposition and in government.

The government has warned that Labor’s proposed plan will drastically increase electricity prices. However, such dire warnings rely on old modelling that has not factored in recent reductions in renewable electricity prices and improvements in energy efficiency.

The end of the resources boom has led many to realise that we need to diversify our economy. Conflicts over coal mining and coal seam gas, as well as big increases in electricity prices, have also challenged past acceptance of the benefits of fossil fuel industries.

Meanwhile, more frequent extreme climate events, coral bleaching and unusual weather patterns have reinforced concerns that climate is actually changing faster than expected.

What will happen to Labor’s policy?

The Labor proposal seems to address many of the political vulnerabilities of its previous policy. At the same time, it captures some of the present government’s agenda.

However, it will be seen as weak by many climate response advocates.

After the anti carbon tax campaign that helped bring Tony Abbott to power in 2013, it remains to be seen whether or not voters are ready to rein in emissions by making pollution a costly business.

Is there a policy you want us to check? Contact us at checkit@theconversation.edu.au.

Alan Pears, Senior Industry Fellow, RMIT University

This article was originally published on The Conversation. Read the original article.

Great Barrier Reef bleaching would be almost impossible without climate change

Andrew King, University of Melbourne; David Karoly, University of Melbourne; Mitchell Black, University of Melbourne; Ove Hoegh-Guldberg, The University of Queensland, and Sarah Perkins-Kirkpatrick, UNSW Australia

The worst bleaching event on record has affected corals across the Great Barrier Reef in the last few months. As of the end of March, a whopping 93% of the reef has experienced
bleaching. This event has led scientists and high-profile figures such as Sir David Attenborough to call for urgent action to protect the reef from annihilation.

There is indisputable evidence that climate change is harming the reef. Yet, so far, no one has assessed how much climate change might be contributing to bleaching events such as the one we have just witnessed.

Unusually warm sea surface temperatures are strongly associated with bleaching. Because climate models can simulate these warm sea surface temperatures, we can investigate how climate change is altering extreme warm conditions across the region.

Daily sea surface temperature anomalies in March 2016 show unusual warmth around much of Australia. Author provided using OSSTIA data from UK Met Office Hadley Centre.

We examined the Coral Sea region (shown above) to look at how climate change is altering sea surface temperatures in an area that is experiencing recurring coral bleaching. This area has recorded a big increase in temperatures over the past century, with March 2016 being the warmest on record.

March sea surface temperatures were the highest on record this year in the Coral Sea, beating the previous 2015 record. Source: Bureau of Meteorology.

Examining the human influence

To find out how climate change is changing the likelihood of coral bleaching, we can look at how warming has affected the likelihood of extremely hot March sea temperature records. To do so, we use climate model simulations with and without human influences included.

If we see more very hot March months in simulations with a human influence, then we can say that climate change is having an effect, and we can attribute that change to the human impact on the climate.

This method is similar to analyses we have done for land regions, such as our investigations of recent Australian weather extremes.

We found that climate change has dramatically increased the likelihood of very hot March months like that of 2016 in the Coral Sea. We estimate that there is at least a 175 times increase in likelihood of hot March months because of the human influence on the climate.

The decaying El Niño event may also have affected the likelihood of bleaching events. However, we found no substantial influence for the Coral Sea region as a whole. Sea surface temperatures in the Coral Sea can be warmer than normal for different reasons, including changes in ocean currents (often related to La Niña events) and increased sunshine duration (generally associated with El Niño conditions).

Overall, this means that the influence of El Niño on the Coral Sea as a whole is weak. There have been severe bleaching events in past El Niño, neutral and La Niña years.

We estimate that climate change has increased temperatures in the hottest March months by just over 1℃. As the effects of climate change worsen we would expect this warming effect to increase, as has been pointed out elsewhere.

March 2016 was clearly extreme in the observed weather record, but using climate models we estimate that by 2034 temperature anomalies like March 2016 will be normal. Thereafter events like March 2016 will be cooler than average.

Overall, we’re observing rapid warming in the Coral Sea region that can only be understood if we include human influences. The human effect on the region through climate change is clear and it is strengthening. Surface temperatures like those in March 2016 would be extremely unlikely to occur in a world without humans.

As the seas warm because of our effect on the climate, bleaching events in the Great Barrier Reef and other areas within the Coral Sea are likely to become more frequent and more devastating.

Action on climate change may reduce the likelihood of future bleaching events, although not for a few decades as we have already built in warming through our recent greenhouse gas emissions.

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A note on peer review

We have analysed this coral bleaching event in near-real time, which means the results we present here have not been through peer review.

Recently, we have started undertaking these event attribution analyses immediately after the extreme event has occurred or even before it has finished. As we are using a method that has been previously peer-reviewed, we can have confidence in our results.

It is important, however, that these studies go through a peer-review process and these results will be submitted soon. In the meantime we have published a short methods document which provides more detail.

Our results are also consistent with previous studies (see also here and here).

Andrew King, Climate Extremes Research Fellow, University of Melbourne; David Karoly, Professor of Atmospheric Science, University of Melbourne; Mitchell Black, PhD Candidate, University of Melbourne; Ove Hoegh-Guldberg, Director, Global Change Institute, The University of Queensland, and Sarah Perkins-Kirkpatrick, Research Fellow, UNSW Australia

This article was originally published on The Conversation. Read the original article.