07 January 2014

Australia’s hottest year was no freak event: humans caused it

by Sophie Lewis and David Karoly, via The Conversation

Australia saw extreme heat and bushfires in 2013. Flickr/Rossco ( Image Focus Australia )

The Bureau of Meteorology has confirmed that 2013 was the hottest year in Australia since records began in 1910.

Unusual heat was a persistent feature throughout the year. For the continent as a whole, we experienced our hottest day on record on January 7. Then January was the hottest month on record, and the 2012-13 summer was the hottest recorded for the nation.

The nation-wide temperature record set for the month of September exceeded the previous record by more than a degree. This was the largest temperature anomaly for any month yet recorded.
 Averaged across all of Australia, the temperature for 2013 was 1.2C above the 1961-1990 average, and well above the previous record hot year of 2005 of 1.03C above average.

What caused these extreme temperatures? Climate scientists have a problem: because climate deals with averages and trends, we can’t attribute specific records to a particular cause.

But our research has made significant headway in identifying the causes of climate events, by calculating how much various factors increase the risk of extreme climate events occurring. And we have found sobering results.

We previously analysed the role human-caused climate change played in recent extremes across Australia.

For various record-breaking 2013 Australian temperatures, we investigated the contributing factors to temperature extremes using a suite of state-of-the-art global climate models. The models simulated well the natural variability of Australian temperatures.

Using this approach, we calculated the probability of hot Australian temperatures in model experiments. These incorporated human (changes in greenhouse gases, aerosols and ozone) and natural (solar radiation changes and volcanic) factors. We compared these probabilities to those calculated for a parallel set of experiments that include only natural factors. In this way, natural and human climate influences can be separated.

In our previous studies, we then applied an approach (known as Fraction of Attributable Risk) widely used in health and population studies to quantify the contribution of a risk factor to the occurrence of a disease. Health studies, for example, can quantify how much smoking increases the risk of lung cancer.

Using the climate models, the Fraction of Attributable Risk (FAR) shows how much the risk of extreme temperatures increases thanks to human influences.

In our earlier study of our record hot Australian summer of 2012-13, we found that it was very likely (with 90% confidence) that human influences increased the odds of extreme summers such as 2012-13 by at least five times.

In August 2013, Australia broke the record for the hottest 12-month period. The odds of this occurring increased again from the hottest summer. We found that human influence increased the odds of setting this new record by at least 100 times.

Recent extreme temperatures are exceeding previous records by increasingly large margins. The chance of reaching these extreme temperatures from natural climate variations alone is becoming increasingly unlikely. When we considered the 12-month record at the end of August, it was nearly impossible for this temperature extreme to occur from natural climate variations alone in these model experiments.

We have just completed a preliminary investigation of contributing factors for the record Australian temperature in the 2013 calendar year.

In the model experiments, it is impossible to reach such a temperature record due to natural climate variations alone. In climate model simulations with only natural factors, none of the nearly 13,000 model years analysed exceed the previous hottest year recorded back in 2005.

Australian annual temperature changes (relative to 1911-1940 average) for observations (dashed black) and model simulations with natural influences only (green) and with both human and natural influences (red). The grey plumes indicate the range of values simulated across nine global climate models used. Average Australian temperature anomalies are indicated for 2013 and the previous hottest year on record in 2005. David Karoly & Sophie Lewis

In contrast, in model simulations including both natural and human factors, such as increasing greenhouse gases, record temperatures occur approximately once in every ten years during the period 2006 to 2020. (On a mathematical note, as there is no instance in which the record hot yearly temperature occurred without human contributions, the FAR value is one.)

Probabilities of annual average temperatures for Australia from climate model simulations including natural influences only (green) and both natural and human climate influences (red) for model years 2006-2020. The vertical lines show the temperature anomalies observed in 2013 and in 2005 (the previous hottest year observed). David Karoly & Sophie Lewis

Clearly both natural climate variability and global warming from humans contribute to recent temperature records. Natural variability always plays a major role in the occurrence of weather and climate extremes. But in the case of our recent hottest year on record, human-caused global warming made a crucial contribution to our extreme temperatures.
Our extensive catalogue of 2013 record-breaking events in Australia occurred in a global context of increasing temperatures that must be considered. Globally, 2013 will likely rank as the 6^th hottest year recorded.

So to return to our question, what caused the 2013 record hot year across Australia? Simply put, our climate has changed due to human activities. Recent extremes, such as this hot year, are occurring well outside the bounds of natural climate variations alone.

RELATED STORIES

• BoM: Annual climate statement 2013

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A lot more is at stake than just whaling

Posted 6 hours 59 minutes ago

Photo: New images of Japanese whaling have triggered fresh calls for the Abbott Government to take action. (AAP: Tim Watters/Sea Shepherd Australia)

Enforcing Australian law against Japanese whalers could unleash a diplomatic and legal maelstrom with serious consequences for Australia’s Antarctic claim – that’s something Greg Hunt was right to avoid, writes Donald Rothwell.

Despite the criticism from the Australian Greens and the Sea Shepherd Conservation Society, Environment Minister Greg Hunt has made the right call in electing to not send an Australian government ship to monitor the Japanese whaling fleet this summer.

On December 22, Hunt announced that the Abbott Government would undertake aerial surveillance and monitoring of the Japanese whalers, most likely relying upon a civilian Airbus A319 that is currently under charter to the Australian Antarctic Division.

Sea Shepherd has now released video images of the Japanese undertaking their annual whaling operations, and this has triggered fresh calls for the Abbott government to be taking action.

While in Opposition, Hunt regularly called for the Gillard government to send an Australian ship to the Southern Ocean to act as a “cop on the beat”. The Coalition indicated that if elected they would act on this promise.

Australia did send a monitoring ship to the Southern Ocean in 2008 when the newly elected Rudd government sent the ACV Oceanic Viking to monitor the Japanese whalers and collect evidence for a potential international legal challenge. Graphic photographic evidence was obtained by the Oceanic Viking, which was also on hand to end a standoff that developed between Sea Shepherd and the Japanese whalers after two of the conservationists had boarded one of the whaling ships.

Since that time, however, no further Australian monitoring operations have been conducted. Nevertheless, there were some legitimate expectations that this year would be different, and Sea Shepherd’s spokesperson, Bob Brown, has been calling the government to account. Hunt has now indicated that Australian aerial surveillance will commence soon, but importantly this will not be a law-enforcement operation.

The failure of successive Australian governments to undertake monitoring of Japanese whaling in the Southern Ocean, and enforcement of Australian law against whaling, has continually frustrated Sea Shepherd. They and other environmental groups point to a 2008 Federal Court ruling which found that the activities of the Japanese whalers were in contravention of the Environment Protection and Biodiversity Conservation Act. That Act established an Australian Whale Sanctuary around Australia and offshore the Australian Antarctic Territory. All whaling within the Sanctuary, which extends 200 miles from the coast, is prohibited. The Federal Court found in favour of an application sought by Humane Society International that the Japanese whalers were acting in contravention of Australian law; however, those orders have never been enforced. Why then has Australian law not been enforced against the Japanese whalers?

It is not widely appreciated that notwithstanding Australia’s longstanding claim to the Australian Antarctic Territory, that claim is not widely recognised. In fact only France, New Zealand, Norway and the UK formally recognise the Australian claim, and those countries also have territorial claims in Antarctica. Not only is Australia’s Antarctic claim not widely recognised, Australia is also compromised from actively asserting its sovereignty in Antarctica under the terms of the 1959 Antarctic Treaty.

The Treaty was negotiated at the height of the Cold War at a time when there was grave concern that Antarctica could become the scene of territorial dispute between America and Russia. Article IV of the Treaty attempted to settle these disputes by putting to one side all territorial issues, and by and large it has been very successful. One element of this settlement was that Australia also agreed to limitations on the exercise of Australian law against foreign nationals. As a result, any attempt by Australia to enforce its laws against foreigners in the Australian Antarctic Territory including the adjacent waters of the Australian Whale Sanctuary would be seen as a violation of the Treaty.

This reality was recognised by former Coalition Attorney-General Philip Ruddock in submissions made to the Federal Court in 2004. Australia’s Antarctic legal reality is that active enforcement of Australian law that prohibits whaling in the Australian Whale Sanctuary against the Japanese whalers could unleash a diplomatic and legal maelstrom with very serious consequences for Australia’s Antarctic claim and for the Antarctic Treaty. This is something which any Australian government would wish to avoid.

As a result, Greg Hunt’s decision to undertake aerial monitoring of the Japanese whalers is a more prudent course of action. It gives to the Australian government some capacity to exercise surveillance of whaling while remaining at arms’ length from any Southern Ocean confrontations that may develop between Sea Shepherd and the whalers. The Abbott Government is also right to be cautious at this time about not seeking to inflame tensions with Japan over whaling.

The position of both countries is well known. In 2010 Australia commenced an historic challenge in the International Court of Justice against the international legal validity of Japan’s ongoing conduct of its Southern Ocean whaling program. That case concluded in July and a decision is expected in the next few months. Australia’s case before the International Court was that Japan’s conduct is in violation of the 1946 International Convention for the Regulation of Whaling. Mindful of the limitations created by the Antarctic Treaty, the Australian case did not rely upon enforcement of Australian law. The Abbott Government is right to now await the International Court’s decision before making its next move on whaling.

Donald Rothwell is Professor of International Law at the ANU College of Law, Australian National University. View his full profile here.

ACCC chairman Sims argues the benefits of privatisation

Updated 1 hour 21 minutes ago

Photo: Australia Post has been put forward as a potential privatisation target by some think tanks. (Nic MacBean: ABC News)

Map: Australia

The competition watchdog is urging governments to sell assets to boost national productivity.

The Australian Competition and Consumer Commission chairman Rod Sims says the root and branch review of competition policy by the Federal Government should be as broad as possible, as privatisation and more competitive markets offer the best possibility of productivity improvements.

Mr Sims says, for a start, state governments should privatise energy companies, a move he believes will bring down electricity prices.

“When the private sector owns assets that does provide better incentives for better performance,” he told ABC’s News Radio.

“I did comment on the energy sector, which is a sector I know fairly well. I’m quite confident that had the network assets in NSW and QLD been owned by the private sector we’d probably have lower electricity prices than we do now.”

An article in this morning’s Australian Financial Review, based on an interview with Mr Sims, says that he has called for Federal Government to sell Medibank Private and Australia Post.

However, Mr Sims has told News Radio that he was not advocating for the sale of particular Government-owned businesses.

“Australia Post, that’s really an issue for government, I was making a general point this morning, and I’ll really leave it at that,” he told News Radio’s Marius Benson.

“I think there are direct experiences you can draw from the energy sector, but I’ve really got no parallel from which to comment on Australia Post, or Medibank Private for that matter.”

Mr Sims adds, however, that the only good reason for government ownership is because it has particular social objectives in mind.

“If all you’re after is maximum efficiency then there’s no question that you’d have those assets owned by the private sector,” he argued.

“If you’re continuing to own them by government, then that’s because you’ve got some social objective to achieve.

“If you have a social objective, it’s worth specifying what that is, and I suspect there’s probably more direct ways to achieve that social objective.”

‘Fat removed’

The union that represents postal workers has rejected Mr Sims’s arguments around efficiency, saying that Australia Post has become “lean and mean” since being corporatised in the 1980s.

“Any fat that existed in the organisation has long since been removed, our members have delivered untold productivity gains over the past 20 years,” said Martin O’Nea, the national assistant secretary of the Communication Workers Union.

“There may be some fat within Australia Post that may be up the top of the organisation – the CEO’s remuneration this year went from $2.8 million to $4.7 million.

“But, regarding the corporation as a whole, we see it as a pretty lean, mean fighting machine and probably the world’s best postal service.”

Mr O’Nea says Australia Post has also returned more than $800 million in dividends to taxpayers over the past three years.

He also warns that Australia Post’s less profitable but socially useful services, such as relatively affordable and timely mail and parcel deliveries to rural and regional Australia, would likely suffer if it was privatised.

“With a privatised Australia Post, would them services that people have seen in the past three years remain the same?” Mr O’Nea asked rhetorically.

“We’d venture that the experience that regional and rural Australia have had with privatisation in the past would leave them to believe that it certainly wouldn’t.”

The Government has launched a scoping study into the possible sale of Medibank Private, which is due to report next month.