By Dr Narelle Fegan and Dr Andrew Leis
Keeping our food safe
The recent outbreak of hepatitis A, which is thought to be associated with the consumption of frozen berries, has highlighted food safety concerns and sparked debates around country of origin labelling and testing of imported foods. Ensuring the safety of our food supply can be a complex process that involves maintaining good hygienic practices in the production and handling of foods at all stages between the farm and consumption.
With some foods, we can reduce the risk of foodborne illness through a heating process, which includes practices like cooking, canning and pasteurisation. However, with fresh produce (such as leafy green and fruits), a heating step is less desirable – we have to rely more on hygienic production to deliver a safe food product. There are quality assurance schemes in place to ensure that fresh produce is grown, harvested, packed and transported to limit contamination by foodborne pathogens.
These schemes rely on people involved in all parts of the production chain following the procedures outlined, to deliver a product that is safe to consume. Such quality assurance schemes operate across the globe and imported products are required to meet the same hygienic standards as food produced in the importing country.
Can testing of food ensure it is safe to eat?
Microbiological testing of foods is only one aspect of quality assurance schemes designed to help keep our food safe. Scientific evidence and history tells us that testing of products for pathogens is not an efficient way of determining if food has been contaminated.
This is particularly true of pathogens that occur very rarely in food (such as hepatitis A) as only a very small amount of the food will be contaminated, and we can’t guarantee we will sample the portion of food where contamination occurs. The difficulties associated with pathogen testing of foods include:
- Contamination is not evenly distributed within the food and only certain portions of the food may contain the pathogen.
- Testing for foodborne viruses destroys the portion of food that is tested.
- Because the food is destroyed during testing, not all of the food can be tested as there would be nothing left for us to eat. Only some of the food can be tested – but sampling plans have been developed to try and maximise the chances of detecting foodborne pathogens.
- Testing methods for foodborne viruses in particular can be difficult to perform, as we have to try and isolate viruses and their genetic material from foods which are often very complex in nature (containing fats, sugars and salts, which can all make it more difficult to detect pathogens).
For these reasons testing of food is only one part of quality assurance schemes, with more attention focusing on hygienic production to limit the opportunities of food becoming contaminated with pathogens.
Why would frozen berries be at risk of carrying hepatitis A?
Freezing is a highly effective and convenient way to increase the shelf-life of foods, and unlike heat-based sterilisation techniques, it preserves most of the nutritional value of the food (some components, like vitamins, are quickly destroyed by heat). Freezing not only prolongs shelf life but also allows us to enjoy very seasonal products, such as berries, at any time of the year.
Preservation of viruses and bacteria during freezing is affected by the rate of freezing and the amounts of sugars and other molecules nearby that help to slow the growth of ice crystals. In a household freezer, water freezes quite slowly – consider the time it takes to freeze water in ice cube trays. Slow freezing favours the formation of ice crystals. As the crystals grow in size, they can kill some bacteria and viruses. On the other hand, high local concentrations of sugars and other molecules can protect the microorganisms from damage.
Frozen berries are generally safe to eat, and have only occasionally been involved in foodborne outbreaks. Hepatitis A virus infection as a result of eating contaminated food (not just berries) is also very rare, particularly in Australia where on average only five cases a year are associated with food consumption in Australia. This is very small compared to other foodborne pathogens in Australia such as Norovirus, where an estimated 276,000 cases a year are associated with food and bacteria, or Campylobacter where 179,000 cases are associated with the consumption of food.
What can we do to ensure the food we eat is safe?
It is not possible to ensure safety by testing a final product. Therefore, systems based on hazard analysis and identification of critical control points have been developed and adopted by governments and food producers through food regulations, industry guidelines and quality assurance schemes. However, human error through poor planning or poor execution can lead to one or more failures along the supply chain. The best thing we can do to ensure the food we eat is safe is to foster a culture of food safety. This means better educating all those involved in the food industry, as well as governments and consumers, so that they understand the safety risks associated with the production, manufacture and consumption of foods.Food safety needs to be seen as an investment, not a cost.
For more information, visit our website.
You might have heard the oceans are full of plastic, but how full exactly? Around 8 million metric tonnes go into the oceans each year, according to the first rigorous global estimate published in Science today.
That’s equivalent to 16 shopping bags full of plastic for every metre of coastline (excluding Antarctica). By 2025 we will be putting enough plastic in the ocean (on our most conservative estimates) to cover 5% of the earth’s entire surface in cling film each year.
Around a third of this likely comes from China, and 10% from Indonesia. In fact all but one of the top 20 worst offenders are developing nations, largely due to fast-growing economies but poor waste management systems.
However, people in the United States – coming in at number 20 and producing less than 1% of global waste – produce more than 2.5 kg of plastic waste each day, more than twice the amount of people in China.
While the news for us, our marine wildlife, seabirds, and fisheries is not good, the research paves the way to improve global waste management and reduce plastic in the waste stream.
Follow the plastic
An international team of experts analysed 192 countries bordering the Atlantic, Pacific and Indian Oceans, and the Mediterranean and Black Seas. By examining the amount of waste produced per person per year in each country, the percentage of that waste that’s plastic, and the percentage of that plastic waste that is mismanaged, the team worked out the likely worst offenders for marine plastic waste.
In 2010, 270 million tonnes of plastic was produced around the world. This translated to 275 million tonnes of plastic waste; 99.5 million tonnes of which was produced by the two billion people living within 50 km of a coastline. Because some durable items such as refrigerators produced in the past are also thrown away, we can find more waste than plastic produced at times.
Of that, somewhere between 4.8 and 12.7 million tonnes found its way into the ocean. Given how light plastic is, this translates to an unimaginably large volume of debris.
While plastic can make its way into oceans from land-locked countries via rivers, these were excluded in the study, meaning the results are likely a conservative estimate.
With our planet still 85 years away from “peak waste” — and with plastic production skyrocketing around the world — the amount of plastic waste getting into the oceans is likely to increase by an order of magnitude within the next decade.
Our recent survey of the Australian coastline found three-quarters of coastal rubbish is plastic, averaging more than 6 pieces per meter of coastline. Offshore, we found densities from a few thousand pieces of plastic to more than 40,000 pieces per square kilometre in the waters around the continent.
Where is the plastic going?
While we now have a rough figure for the amount of plastic rubbish in the world’s oceans, we still know very little about where it all ends up (it isn’t all in the infamous “Pacific Garbage Patch”).
Between 6,350 and 245,000 metric tons of plastic waste is estimated to float on the ocean’s surface, which raises the all-important question: where does the rest of it end up?
Some, like the plastic microbeads found in many personal care products, ends up in the oceans and sediments where they can be ingested by bottom-dwelling creatures and filter-feeders.
It’s unclear where the rest of the material is. It might be deposited on coastal margins, or maybe it breaks down into fragments so small we can’t detect it, or maybe it is in the guts of marine wildlife.
Wherever it ends up, plastic has enormous potential for destruction. Ghost nets and fishing debris snag and drown turtles, seals, and other marine wildlife. In some cases, these interactions have big impacts.
For instance, we estimate that around 10,000 turtles have been trapped by derelict nets in Australia’s Gulf of Carpentaria region alone.
More than 690 marine species are known to interact with marine litter. Turtles mistake floating plastic for jellyfish, and globally around one-third of all turtles are estimated to have eaten plastic in some form. Likewise seabirds eat everything from plastic toys, nurdles and balloon shreds to foam, fishing floats and glow sticks.
While plastic is prized for its durability and inertness, it also acts as a chemical magnet for environmental pollutants such as metals, fertilisers, and persistent organic pollutants. These are adsorbed onto the plastic. When an animal eats the plastic “meal”, these chemicals make their way into their tissues and — in the case of commercial fish species — can make it onto our dinner plates.
Plastic waste is the scourge of our oceans; killing our wildlife, polluting our beaches, and threatening our food security. But there are solutions – some of which are simple, and some a bit more challenging.
If the top five plastic-polluting countries – China, Indonesia, the Philippines, Vietnam and Sri Lanka – managed to achieve a 50% improvement in their waste management — for example by investing in waste management infrastructure, the total global amount of mismanaged waste would be reduced by around a quarter.
Higher-income countries have equal responsibility to reduce the amount of waste produced per person through measures such as plastic recycling and reuse, and by shifting some of the responsibility for plastic waste back onto the producers.
The simplest and most effective solution might be to make the plastic worth money. Deposits on beverage containers for instance, have proven effective at reducing waste lost into the environment – because the containers, plastic and otherwise, are worth money people don’t throw them away, or if they do others pick them up.
Extending this idea to a deposit on all plastics at the beginning of their lifecycle, as raw materials, would incentivize collection by formal waste managers where infrastructure is available, but also by consumers and entrepreneurs seeking income where it is not.
Before the plastic revolution, much of our waste was collected and burned. But the ubiquity, volume, and permanence of plastic waste demands better solutions.
Australia is on track for up to 1.7C of warming this century if the world curbs its greenhouse emissions, but under a worst-case scenario could see anything from 2.8C to 5.1C of warming by 2090, according to new climate change projections released by the CSIRO and the Bureau of Meteorology.
The projections are the most comprehensive ever released for Australia. They are similar to those published in 2007, but based on stronger evidence, with more regional detail. These projections have been undertaken primarily to inform the natural resources management sector, although the information will be useful for planning and managing the impacts of climate change in other sectors.
The new report draws on climate model data used by the Intergovernmental Panel on Climate Change (the IPCC). The Fifth IPCC Assessment Report (AR5), released in 2013 and 2014, used a range various greenhouse gas and aerosol scenarios to project future climate change.
Over the past 10 years, carbon dioxide emissions have been tracking the highest IPCC emission scenario (known as RCP8.5). If there is limited international action to reduce emissions, then projections based on the highest scenario may be realised.
However, if emissions are significantly reduced over the coming decades, then intermediate emissions (RCP4.5) might be feasible. Following the low emissions scenario (RCP2.6) would be very challenging given the current trajectory of carbon dioxide emissions.
How does Australia compare?
By late in this century (2090), Australia’s average warming is projected to be 0.6 to 1.7C for a low emission scenario, or 2.8 to 5.1C under a high emission scenario.
The warming under the high scenario is similar to the global average warming of 2.6 to 4.8C under the high emission scenario reported by the IPCC AR5. However, inland areas of Australia will warm faster than coastal areas.
The new projections should be viewed in the context of what has already been observed. Australia has become 0.9C warmer since 1910. Rainfall has increased in northern Australia since the 1970s and decreased in south-east and south-west Australia.
More of Australia’s rain has come from heavy falls and there has been more extreme fire weather in southern and eastern Australia since the 1970s. Sea levels have risen by approximately 20 cm since 1900.
In future, Australia’s average temperature will increase and we will experience more heat extremes and fewer cold extremes. Winter and spring rainfall in southern Australia is projected to decline while changes in other regions are uncertain.
For the rest of Australia, natural climate variability will predominate over rainfall trends caused by increasing greenhouse gases until 2030. By 2090, a winter rainfall decrease is expected in eastern Australia, but a winter rainfall increase is expected in Tasmania.
Historical climate data can be used as an analogue for the future. The analogue could be a location that currently has a climate similar to that expected in another region in the future.
For example, for a warming of 1.5-3.0C and a rainfall decrease of 5-15%, Melbourne’s climate becomes similar to that of Clare in South Australia, Sydney becomes more like Brisbane, and Brisbane becomes more like Bundaberg in inland Queensland.
Extreme rainfall events that lead to flooding are likely to become more intense. The number of tropical cyclones is projected to decrease but they may be more intense and possibly reach further south. Southern and eastern Australia is projected to experience harsher fire weather. The time in drought will increase over southern Australia, with a greater frequency of severe droughts.
A projected increase in evaporation rates will contribute to a reduction in soil moisture across Australia. There will be a decrease in snowfall, an increase in snowmelt, and therefore reduced snow cover.
Sea levels will continue to rise throughout the 21st century and beyond. Oceans around Australia will warm and become more acidic.
What will Australia look like?
Freshwater resources are projected to decline in far south-west and far south-east mainland Australia. Rising sea levels and increasing heavy rainfall are projected to increase erosion and inundation, with consequent damage to many low-lying ecosystems, infrastructure and housing.
Increasing heat waves will increase risks to human health. Rainfall changes and rising temperatures will shift agricultural production zones. Many native species will suffer from reduced habitats and some may face local or even global extinction.
The most vulnerable regions/sectors are coral reefs, increased frequency and intensity of flood damage to infrastructure and settlements, and increasing risks to coastal infrastructure and low-lying ecosystems.
While reductions in global greenhouse gas emissions would increase the chance of slowing climate change, adaptation is also required because some warming and associated climate changes are unavoidable.
The coastal city of Newcastle is in the midst of a media frenzy, thanks to a string of shark sightings close to popular swimming beaches.
A 15 kilometre stretch of beaches has now been shut for a record six consecutive days, with lifeguards and police craft reporting shark sightings seemingly by the hour. Of most concern have been a purportedly 5 metre, 1,700kg White shark that has been lingering along the coastline; and what is suspected to be a 3 metre tiger shark that was photographed attacking and killing a small dolphin only 50 metres from the shore yesterday (warning: graphic images).
While no attacks on humans in the area have yet been recorded, the sharks have become national celebrities in their own right, with widespread media coverage and commentary. There has even been a Twitter account set up for the @Newy_Shark (which is one account you probably don’t want to be “followed” by).
So what’s the deal here? Are we seeing the real-life return of Jaws? Has a curse been struck down upon the town of Newcastle by Poseidon himself? Is a Sharknado next?
Our resident White shark expert, Barry Bruce, knows a thing or two about these ancient predators. He is one of Australia’s pre-eminent authorities on the species and is the head of our White Shark Research Program. But he is perhaps most famously known for having one of Finding Nemo’s most famous characters named after him.
According to Barry, the story behind Newcastle’s shark saga is far less salacious. Thankfully, we’re not gonna need a bigger blog.
The coastline just north of Newcastle (stretching from the appropriately named Stockton Bight to the even tastier-sounding Seal Rocks) is famously known as being a nursery ground for White sharks. These juveniles are usually about 2-3 metres in length, and a tagging program undertaken by Barry and his team has shown that they are more than prevalent in the area.
Seeing a larger sized White in this area, like the infamous #NewyShark, is slightly less common, but still not at all unusual.
Large White sharks are well known to move up and down the New South Wales coastline, stopping in certain areas when food is prevalent. White sharks have been exhibiting this exact behaviour for countless millennia – it is only when they stop near a heavily populated area like Newcastle that we would notice.
But these are nomadic creatures, and they won’t stay in one spot for too long. We know through collaboration with our colleagues in New Zealand that white Sharks will travel as far north as the Great Barrier Reef – and even across the Tasman to NZ – in a span of just months.
Barry puts the current concentration of sharks in Newcastle purely down to natural variability. Sharks go where the food goes – if there are more sharks in one area at one point in time, it means there will be less in others.
And while we’re in the mood for debunking myths, here’s another one: dolphins are just as much a food source for sharks as are any other species of their size. While it is uncommon for us to observe – and the images were undeniably distressing – sharks are well-known to attack dolphins. Unfortunately, what Flipper taught us was wrong.
More than anything, Barry says that this is a positive advertisement for the health of marine ecosystems in Australia. That there is a large enough food source to sustain shark populations is a good thing, and should be celebrated.
But of course, it is important for beachgoers to take advice from authorities when entering the water. While this is a natural spectacle that should be enjoyed, it is advisable to do so from a distance – and on land. In time it will run its course, and we can all return to the water.
White shark fast facts:
- A common mistake people make is calling these awesome creatures, ‘Great White Sharks’, it’s actually just ‘White shark’ (Carcharodon carcharias). But we still think they’re still pretty great.
- Sharks play a vital ecosystem role as top predators. Declines in top predators can cascade through the food web, seeing some species groups increase while eliminating others.
- We have one of the most comprehensive White shark research programs in the world, with over 250 tagged White sharks in Australian waters. Check out a few shark tracks on our website.
- Our tagging program provides us with a good idea of migration patterns – we know for example that there is an East and a Southwest population.
- Our research on White sharks is a collaborative project funded under the Australian Government’s National Environmental Research Program.
- We tag these beauties in a very humane way – in a sling, in the water:
The latest round of bushfires, which claimed 27 homes in the Adelaide Hills, has once again highlighted the importance of planning for the worst. Mercifully, no human lives were lost, and it will be important to learn whatever lessons we can to avoid future tragedies.
My colleagues and I analysed 825 deaths in 260 Australian bushfires from 1901 to 2011, and our research has revealed some compelling evidence to help guide residents to plan for future bushfires.
Most people (58%) lost their lives when caught out in the open. Strikingly, 72% of those people were within 200 m of their own homes (this statistic is based only on cases where details are accurately known).
I encourage you to imagine what circumstances and decisions might have led to these outcomes. Do a large number of people simply wait to see if the fire is really going to arrive on their doorstep?
Bushfire deaths within a house are most prevalent during our most severe fire events, representing 75% of all fatalities during bushfires that occurred on days with “catastrophic” (code red) fire danger conditions. This is despite them representing only 27% of all bushfire deaths.
Of those who died inside homes, 92% were in rooms that did not have a door that led directly to the exterior of the house (once again, this is based only on cases where circumstances are accurately known). This raises uncomfortable questions: why did these people apparently not try to leave the home as the house fire developed? Were they monitoring the conditions outside as the fire passed? Had they thought about which exit was the safest?
Homes under attack
When a fire arrives at a property, the house will experience “ember attack”. This attack is strongest as the main fire arrives and will persist for a long time after it has passed, and may also start to happen before the fire actually arrives. If the house is close enough to the bush it may also be affected by radiant heat, and if very close then direct flame contact is possible, although most houses are lost without any direct interaction from a bushfire front – which goes some way to account for the seemingly random loss patterns that occur.
Given the timing and intensity of ember attack, it is no surprise that our data show that houses can ignite before, during, and after a fire front’s passage – with the most likely time being during and immediately after the fire front has passed.
For the relatively small number of houses that ignite before the fire front arrives, the occupants may be faced with life-threatening conditions both inside and outside at the same time. There are also a few cases were houses are built so close to the bush or other combustible elements that even the low-level fire that persists after the main fire front has passed is too intense to survive outside.
Nevertheless, for the vast majority of homes that burn in bushfires, it is likely that at any given time, conditions would be survivable either inside or outside the house. That means that, with the right strategy, lives should not be lost.
Designing a lifesaving strategy
It is interesting to note that the current building codes for bushfire-prone areas include specific fire weather severity limits beyond which these standards may no longer be effective. The standards aim to reduce the risk that a building will catch fire, but they also rule out any guarantee that it won’t. The code also doesn’t address the issues of how fast burning homes might succumb, or of how to provide a safe or effective exit path from the building.
So even if your bushland home is fully up to code, you need to plan for a wide range of scenarios. Fire agencies across Australia have stressed the importance for people living in bushfire-prone areas to develop a fire survival plan, and your local fire agency is the best place to start on developing a plan and educating yourself about the specific local fire conditions you might face.
Once a plan has been developed I encourage residents to test their fire plan by checking whether it answers the following questions:
- At what level of forecast fire weather severity will you retreat to a non-bushfire-prone area for the day?
- Do you understand the local potential fire severity for weather conditions below this level?
- For any given circumstances, what are the signs or triggers that indicate that it is no longer safe to evacuate to a non-bushfire prone area? For some isolated communities this will be when fire weather severity passes a certain level; for other, less isolated residents it will be when they are no longer certain that the roads are moving freely and fire will not impact their travel route.
- What and where is your personal protective equipment and firefighting tools?
- Is the property free from combustible items under or adjacent to the home?
- Is the home in an acceptable state of repair to survive a bushfire?
- Which areas would be the safest external location to move to if it becomes impossible to stay in the house?
- Does the path leading to this cleared area involve walking over or past combustible elements such as vehicles and decking?
- How do I monitor all rooms and cavity areas of the home for signs of ignition of fire development inside the house?
- What do you have on hand to monitor and put out these fires (stored water, ladders to monitor internal roof space, etc.)?
- If you can’t put them out, which exit path is the most appropriate?
A deep understanding of the nature of bushfire threat is your best tool in assessing and managing your own risk.
Thought-provoking gifts are tricky to think up. So to help out, we took a wander around the interwebs to gather some ideas for those science-minded giftees in your life. From the social media team to you, here are our suggestions for science-themed presents – including crafts from Etsy, and pop-science books.
Scientific gifts from Etsy
Etsy is a great place to shop for niche gifts for loved ones. Here is a quick list of scientific present ideas from some e-stallholders on Etsy:
The owner of this stall is an ecologist and Ph. D. Candidate who crafts handmade jewellery and science-themed drink coasters. The coasters are marble and have antique-inspired scientific illustrations such as micro-organisms and cellular division:
3. iPhone and business card cases by T Rowan Design
This stall prints custom or science-themed images onto cases for Samsung and iPhones (generations 4-6) as well as business card cases.
Antique Wall Prints has more science-themed prints than there is wall space. They are based in Adelaide, too, so the shipping should be snappy.
These educational scrolls from Lunartics are vintage, so they are more costly than the above prints. But, they look amazing and are in great condition.
And of course, we can’t forget our beloved CSIRO shop for all of your microscopy and sticky, tumbling frog needs.
Popular science books of 2014
We at CSIRO love a good read, especially when it’s science material delivered at its most evocative. Here are six of this year’s pop-science books that we highly recommend this Christmas:
1. Night School: Wake up to the power of sleep by Richard Wiseman
Richard Wiseman is a psychologist, illusionist, and fantastic writer. In this book, Professor Wiseman expounds the latest research on sleep, dreams, nightmares, and other strange night-time phenomena. The book also has interactive elements, including sleep-related surveys, and downloadable, sleep-inducing tracks.
2. The Sense of Style: The Thinking Person’s Guide to Writing in the 21st Century by Steven Pinker
This is not strictly a science read, but it is written by a world-class science writer – Steven Pinker. Pinker is also a psychologist who specialises on the evolution and acquisition of language. In this book he advocates a common-sense use of language over the arbitrary rules of some grammarians. And he should know, Professor Pinker also chairs the Usage Panel of the American Heritage Dictionary. We highly recommend his previous books, too: The Blank Slate and The Better Angels of Our Nature.
3. Gulp: Adventures on the Alimentary Canal by Mary Roach
Ever wanted to shrink down and travel through innerspace, all the way through the alimentary canal, from the mouth to the ar…other end? This book by Mary Roach might allow such a journey, albeit a vicarious version. Mary’s books tackle the quirkier and sometimes more vulgar aspects of science, and this book is no exception. The reader is taken on a ride into the mouth, down the oesophagus, into the belly, and then the various tubes that come afterwards, learning all the way how each section contributes to our greater good.
4. An Astronaut’s Guide to Life on Earth by Chris Hadfield
Chris Hadfield is a retired astronaut and a former commander on the International Space Station. He has gained widespread popularity through his use of social media, connecting the public with the processes and experiences of life in space. Last year Colonel Hadfield produced the first music video clip in space, a cover of David Bowie’s Space Oddity, which can be viewed here. His latest book describes the life of an astronaut (how to be the ultimate renaissance man) and his various trials as an astronaut, in space and on Earth.
5. Undeniable: Evolution and the Science of Creation by Bill Nye
Here, Bill Nye, host of ‘Bill Nye the Science Guy’, uses his clear and accessible communication skills to explain one of the greatest ideas in all of science: Evolution by means of natural selection. Inspired by a recent debate on the topic, Nye took to writing a description of evolution for a popular audience. If you’re looking for a breezy brush up on biologists’ favourite subject – try this one.
6. The Accidental Universe: The World You Thought You Knew by Alan Lightman
Alan Lightman is an MIT physicist and popular science writer. This book travels through space and time, to the beginning, to the smallest scale, and through dimensions – all in under 200 pages. In this pithy travel through physics, you also get a little bit of science-inspired philosophy, what a treat. As well as a genius physicist, Lightman is also a humanitarian, starting up foundations to support women in developing countries. This book is sure to get you thinking about sciences tell on reality and our place in it.
That’s it for our Christmas-themed posts this year. We hope you enjoyed them! In the New Year we’ll be compiling a list of staff-recommended scientific attractions for the holidays, as well as some science-themed apps for your smart machines. Wishing you a merry Christmas and happy New Year!
With the year winding up, we thought we’d look back on the stories that struck a chord – or a nerve – in 2014. It was a mixed bag, ranging from the sublime to the implausible.
The sublime was definitely the Rosetta mission and Philae’s (not quite) perfect landing on the surface of the (not quite) evocatively-named comet 67P/Churyumov–Gerasimenko. Thanks to the wonders of modern communication, never before in the field of exploration have so many people so fervently urged a fridge-sized box on legs half a billion kilometres away to succeed against the odds.
We played a back-up role in the landing. Using the DSS34 antenna, NASA’s Deep Space Communication Complex (managed by CSIRO at the Tidbinbilla site) provided ongoing back-up communication coverage between Rosetta/Philae and the anxious science team at ESA’s mission control centre in Germany.
It’s a lot more down to earth, and of more practical use at the moment, but some news about renewable energy was just as exciting. If there was one good thing about the alarmingly warm autumn eastern Australia had in 2014, it was this: a team of solar thermal engineers and scientists at our Energy Centre in Newcastle used the sunlight flooding their solar fields to produce ‘supercritical’ steam, at the highest temperature and pressure levels ever recorded using solar power.
That sounds impressive when you just say it, but to realise how impressive it is, you need to know that supercritical steam is the ultra-hot, ultra-pressurised steam used to drive the world’s most advanced power plant turbines. This is the solar energy equivalent of breaking the sound barrier. Solar thermal power plants have traditionally only operated at ‘subcritical’ levels – the heavy lifting was left to fossil fuels. But now we’ve demonstrated that the power plants of the future could feasibly use the zero emission energy of the sun to reach peak efficiency levels – and at a cheaper price. The technology’s not ready for commercialisation yet, but the breakthrough has attracted a lot of interest.
There are other kinds of stories that always attract a lot of interest, and food safety – as we’re discovering yet again with the current raw milk controversy – is one of them. Fortunately, there was a pretty positive reaction to our story on whether it’s safe to cut the mould off food. Unlike supercritical steam, the comments generated more light than heat, which is always both gratifying and a relief. We came down firmly on the side of a conservative approach (and that’s not conservative of the food, more of the health). And in response to the comments, we published a clarification about spoilage in other kinds of food – the beauty of a blog is that you can incorporate the feedback from your readers. We love intelligent, constructive comments. So a big thanks to those who made them.
We got quite a bit of interest, too, for a story about 3D-printed mouthpieces for people with sleep apnoea. Sadly, a lot of this interest seemed to be tinged with a note of desperation. While we were delighted to be able to tell a story that gave hope to so many stressed snorers and their loved ones, it wasn’t nearly as enjoyable to have to let people know they couldn’t be part of trials for the mouthpieces. On the up-side, however, Oventus, the company making the mouthguards, tells us that they’re steadily getting closer to being commercially available. Since we’ve had interest from several countries, we think they might have a hit on their hands. We just hope they’re able to help the man who told us his snoring is so bad that the cat left home. The cat would probably be grateful too. We suggested a cat hammock in the meantime.
And to continue on the camping theme, we got a lot of love for a story about backpacks. Bees with backpacks. This is just a terrific bit of research. We’ve put tiny 2.5mm sq RFID chips on the backs of 5000 bees. Now, this sounds a bit weird, but there’s an excellent reason for it. Collecting bee movement information at this scale will allow researchers to generate a four-dimensional model (three dimensions plus time) of bee behaviour and the way they move through the landscape. This is vital information: wild honey bee populations are dropping drastically or vanishing altogether. In some cases this is because of the parasitic Varroa mite. In others it’s Colony Collapse Disorder, believed to be caused by diseases and agricultural pesticides.
Everybody seems to love stories about 3D printing (and who can blame them?). We had a couple of rippers this year. First, there was the 3D-printed bike. More specifically, the bike with 3D-printed titanium parts, specifically engineered to provide ‘infinite flexibility’ and give a far superior riding experience, along with quite a bit of bike envy. It also looks seriously good, and its proud owner/designer seems to be very pleased with it. We don’t know if the man at the centre of our other big 3D printing success this year (there’s one other, but we’ll come to that later) is a bike rider, but thanks to some brilliant work by our titanium printing team, he has the option. He had cancer in his heel bone, and the standard treatment for that is to amputate the leg below the knee. Fortunately, his surgeon had seen a story we did last year, about 3D-printed shoes for horses, and wondered if it was possible to print a new heel bone to replace the cancerous one. It was. One of the strengths of 3D printing is its ability to produce complex structures quickly: within two weeks of his surgeon making the call, the new heel bone was in place. We can now reveal that we sat on that story for months, busting to tell everyone, but couldn’t until after the three-month check-up showed everything was working well. We were very relieved – but not nearly as relieved as the recipient.
Not all health problems have as quick a fix as supplying a new part. It would be good if they did, but sometimes treatment is a long haul. Overweight and obesity fits into that category, but our new Impromy™ diet program helps to make the long haul as pleasant as it can be. Our talented team worked with Probiotec Ltd to develop a holistic program that includes meal replacements. This is a big help for people with busy lifestyles: often a reason that cooking and meal preparation fall down the priority list. It’s a research-based program that builds on our Total Wellbeing Diet research and leverages it to use with smart phone technology in a community pharmacy setting.
But we’d be very grateful if you disposed of the wrappers from the meal replacements carefully. Sometimes the big science stories aren’t good news, and this one certainly wasn’t. We went looking for rubbish, and what we found was sobering. In a survey of the entire Australian coast at 100 km intervals, with help from school groups and citizen scientists, we found that our shorelines are littered with debris. About 75 per cent of it is plastic, and, in a pretty grim indictment of our throwaway culture, you can expect to find anything from a few thousand to over 40,000 pieces of plastic per square kilometre in our coastal waters. Worse, we can extrapolate from this to predict that by 2050, 95 per cent of seabirds will have plastic in their gut.
If it’s bad news you want, though, our biannual State of the Climate report is – sadly – hard to beat. It’s getting warmer. Seven of the ten warmest years on record in Australia have occurred since 1998. When we compare the past 15 years with the period between 1951 and 1980, we find that very warm months are five times as frequent. The frequency of very cool months, conversely, has dropped by about a third. Extreme fire weather risk has increased, and the fire season has lengthened across large parts of Australia since the 1970s. Autumn and winter rainfall is declining, particularly in south-western and south-eastern Australia. Heavy rainfall with the potential for flooding is projected to increase. Australian average annual rainfall has increased slightly, largely from increases in spring and summer rainfall. Unfortunately, this doesn’t offset the autumn and winter declines in southern parts of Australia: it’s mainly concentrated in north-western Australia.
We don’t want to end on such a depressing note though, so … DRAGONS! This is the implausible bit, and it was absolutely, positively our biggest hit of the year. You might remember it. Seven-year-old Sophie wrote to us, asking if we could make her one. So we, er, did. Not a flying, screeching, fire-breathing one (we haven’t got the lab space), but a 3D-printed (there it is again) titanium (there’s that again too) one. This story captured the imagination of many people (140 000 page views worth), and might even have inspired Sophie, or another child, to become a scientist. We loved the comments we got on this story nearly as much as everyone seemed to love Sophie’s original letter. The erudite discussion on the history and physiology of dragons was a delight. Thank you to all the readers and dreamers who contributed.
Now, how would we go using dragons to generate supercritical steam? Just a thought…