Lucky winner: why this beach in WA claims the crown of Australia’s whitest sand



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The winner! Lucky Bay, Cape Le Grand National Park, Esperance WA.
Peter Masters

Noel Schoknecht, Murdoch University

In 2005, when I was chair of the National Committee on Soil and Terrain, I started a debate: where is Australia’s whitest beach? This was a diversion from the committee’s normal business of looking at the sustainable management of Australia’s soils, but it led down a path I hadn’t expected.

What began as a bit of after-hours banter became a serious look across Australia in search of our whitest beaches. New South Wales had already laid claim to the title, arguing that Hyams Beach at Jervis Bay has the whitest sand in the world, purportedly backed up by Guinness World Records.

As it turned out, both claims were false. Guinness World Records has no such category, and the whitest beach (as we found) is actually elsewhere.

Hyams beach in Jervis Bay, NSW, has been rumoured to have the whitest sand in Australia.
Kristina Kl./Flickr, Author provided

So we drafted terms of reference, and the search for Australia’s Whitest Beach began. Over the next year samples were collected across the nation. The criteria were simple: samples had to be taken from the swash zone (the gently sloping area between the water and the dunes) and the samples could not be treated in any way apart from air-drying. No bleaching. No sieving out of impurities. Marine environment only.

The results of the first judging in 2006 were startling. Of all the states and territories, the much promoted Hyams Beach in New South Wales came in fourth. Third was Victoria, second Queensland, and first Western Australia.

The other states and territories came in at Tasmania fifth, Northern Territory sixth, and South Australia seventh. The ACT didn’t have a beach to sample, although technically some of the Commonwealth lands around our coasts could possibly come in under their banner (but that’s another debate altogether).

A sample of the main contenders for the whitest beach in Australia. Unfortunately, samples submitted from South Australia didn’t make the final cut.
Photo: Noel Schoknecht, Author provided

The winning beach was Lucky Bay in Cape Le Grand National Park on WA’s south coast, but in reality any of the beaches in this area could have been winners – Hellfire Bay, Thistle Cove and Wharton’s beach (just to name a few) are all magnificently white.

A quick qualification here: the southwestern end of Lucky Bay, where many people enter the beach, is covered with seaweed – not the whitest bit! I should also note that all of the finalists in the whitest beach challenge were in their own right fabulously white. But when compared side-by-side, some beaches are clearly whiter than others.

The Queensland team felt aggrieved, so in 2007 I carried out a repechage with new samples from Queensland at Whitehaven Beach in the Whitsundays, and Lake McKenzie on Fraser Island. Lake McKenzie was ultimately disallowed as it is a freshwater lake and the rules stipulated a marine environment. Meanwhile, Whitehaven didn’t quite cut the mustard in the judging and Lucky Bay in WA was again the winner.

Whitehaven beach in Queensland just missed out on the top spot in the recount.
Jared Yeh/Flickr, CC BY-NC-SA

So what makes a beach white, and is it important anyway?

The assessments were based on a visual comparison, so to remove any possible visual bias after the 2007 challenge all the samples were scanned for their reflectance – how much light bounced off the sand, essentially – in the visible and infrared wavelengths. Our assumption was that higher reflectance throughout the visual spectrum correlates with greater whiteness.

As it turned out, the results from the scanning exactly correlated with the visual assessments. The eye is quite good at discerning small differences in colour and reflectance. (More background and the results from the competition are available here.)

So what makes a beach white? Obviously, a pristine environment helps. Another factor is the distance from rivers, which deliver coloured organic and clay contaminants to the coast.

The geology of the area and the source of the sand are also critical, with quartz seemingly a major requirement for fine sands. Most white sandy beaches are derived from granitic, or less commonly sandstone, geologies that weather to produce fine, frosted quartz sand grains. Interestingly, sands made from shell or coral fragments just aren’t as white.

The source of the sand is very important; sand made from shells or coral aren’t as white as quartz.
Tracey Croke/Flickr, CC BY

Is it important?

While this competition began in fun, I do believe it’s important. Beaches are places of refuge in this crazy world, and a pristine white beach indicates a cleanliness that is worth striving for. The reflectance of light off these sands through shallow waters near the beach creates a surreal, magical turquoise colour. White beaches are like the canary in the coalmine – once they’re spoiled, we know we’re in trouble.

Even though this study was a first look at some of Australia’s whitest beaches, and sampling was limited, it did highlight the sheer number of wonderful sandy beaches that Australia has.

The story’s not finished though. There are many white beaches out there yet to be sampled, and if you’d like to alert me to your potentially award-winning beach please email me or leave a comment on the whitest beach website.

It’s our responsibility, and I believe honour, to protect these amazing places. I’m sure there are more wonderful beaches out there that we haven’t sampled which may defeat Lucky Bay.

The ConversationShelburne Bay in northern Queensland, for example, is a contender yet to be sampled, and there are some magnificent beaches on the east coast of Tasmania. Whatever the outcome, let’s celebrate the natural wonders that surround our country.

Noel Schoknecht, Senior research associate, Murdoch University

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

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Tasmanian tigers were going extinct before we pushed them over the edge



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Gone since 1936, and ailing since long before that.
Tasmanian Museum and Art Gallery, Author provided

Andrew Pask, University of Melbourne

There’s no doubt that humans killed off the Tasmanian tiger. But a new genetic analysis suggests this species had been on the decline for millennia before humans arrived to drive them to extinction.

The Tasmanian tiger, also known as the thylacine, was unique. It was the largest marsupial predator that survived into recent times. Sadly it was hunted to extinction in the wild, and the last known Tasmanian tiger died in captivity in 1936.

In a paper published in Nature Ecology and Evolution today, my colleagues and I piece together its entire genetic sequence for the first time. It tells us that thylacines’ genetic health had been declining for many millennia before they first encountered human hunters.


Read more: Will we hunt dingoes to the brink like the Tasmanian tiger?


Hounded by hunters.
Tasmanian Museum and Art Gallery, Author provided

Our research also offered the chance to study the origins of the similarity in body shape between the thylacine and dogs. The two are almost identical, despite having last shared a common ancestor more than 160 million years ago – a remarkable example of so-called “convergent evolution”.

Decoding the thylacine genome allowed us to ask the question: if two animals develop an identical body shape, do they also show identical changes in their DNA?

Thylacine secrets

These questions were previously difficult to answer. The age and storage conditions of existing specimens meant that most thylacine specimens have DNA that is highly fragmented into very short segments, which are not suitable for piecing together the entire genome.

We identified a 109-year-old specimen of a young pouch thylacine in the Museums Victoria collection, which had much more intact DNA than other specimens. This gave us enough pieces to put together the entire jigsaw of its genetic makeup.

The preserved young, thylacine with enough DNA to reveal its whole genome.
Museums Victoria, Author provided

Next, we made a detailed comparison of thylacines and dogs to see just how similar they really are. We used digital imaging to compare the thylacine’s skull shape to many other mammals, and found that the thylacine was indeed very similar to various types of dog (especially the wolf and red fox), and quite different from its closest living marsupial relatives such as the numbat, Tasmanian devil, and kangaroos.

Our results confirmed that thylacines and dogs really are the best example of convergent evolution between two distantly related mammal species ever described.

We next asked whether this similarity in body form is reflected by similarity in the genes. To do this, we compared the DNA sequences of thylacine genes with those of dogs and other animals too.

While we found many similarities between thylacines’ and dogs’ genes, they were not significantly more similar than the same genes from other animals with different body shapes, such as Tasmanian devils and cows.

We therefore concluded that whatever the reason why thylacines and dogs’ skulls are so similarly shaped, it is not because evolution is driving their gene sequences to be the same.

Family ties

The thylacine genome also allowed us to deduce its precise position in the marsupial family tree, which has been a controversial topic.

Our analyses showed that the thylacine was at the root of a group called the Dasyuromorphia, which also includes the numbat and Tasmanian devil.

By examining the amount of diversity present in the single thylacine genome, we were able to estimate its effective population size during past millennia. This demographic analysis revealed extremely low genetic diversity, suggesting that if we hadn’t hunted them into extinction the population would be in very poor genetic health, just like today’s Tasmanian devils.

The less diversity you have in your genome, the more susceptible you are to disease, which might be why devils have contracted the facial tumour virus, and certainly why it has been so easily spread. The thylacine would have been at a similar risk of contracting devastating diseases.

The last thylacine alive.
Tasmanian Museum and Art Gallery, Author provided

This loss in population diversity was previously thought to have occurred as a population of thylacines (and devils) became isolated on Tasmania some 15,000 years ago, when the land bridge closed between it and the mainland.

But our analysis suggests that the process actually began much earlier – between 70,000 and 120,000 years ago. This suggests that both the devil and thylacine populations already had very poor genetic health long before the land bridge closed.


Read more: How curiosity can save species from extinction


The ConversationNow that we know the whole genome of the Tasmanian tiger, we know much more about this extinct animal and the unique place it held in Australia’s marsupial family tree. We are expanding our analyses of the genome to determine how it came to look so similar to the dog, and to continue to learn more about the genetics of this unique marsupial apex predator.

Andrew Pask, Associate Professor, University of Melbourne

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

Scars left by Australia’s undersea landslides reveal future tsunami potential



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The Byron Scar, left behind by an undersea landslide. Colours indicate depths.
Samantha Clarke, Author provided

Samantha Clarke, University of Sydney; Hannah Power, University of Newcastle; Kaya Wilson, University of Newcastle, and Tom Hubble, University of Sydney

It is often said that we know more about the surface of other planets than we do about our own deep ocean. To overcome this problem, we embarked on a voyage on CSIRO’s research vessel, the Southern Surveyor, to help map Australia’s continental slope – the region of seafloor connecting the shallow continental shelf to the deep oceanic abyssal plain.

The majority of our seafloor maps depict most of the ocean as blank and featureless (and the majority still do!). These maps are derived from wide-scale satellite data, which produce images showing only very large features such as sub-oceanic mountain ranges (like those seen on Google Earth). Compare that with the resolution of land-based imagery, which allows you to zoom in on individual trees in your own neighbourhood if you want to.

But using a state-of-the art sonar system attached to the Southern Surveyor, we have now studied sections of the seafloor in more detail. In the process, we found evidence of huge underwater landslides close to shore over the past 25,000 years.

Generally triggered by earthquakes, landslides like these can cause tsumanis.

Into the void

For 90% of the ocean, we still struggle to identify any feature the size of, say, Canberra. For this reason, we know more about the surface of Venus than we do about our own ocean’s depths.

As we sailed the Southern Surveyor in 2013, a multibeam sonar system attached to the vessel revealed images of the ocean floor in unprecedented detail. Only 40-60km offshore from major cities including Sydney, Wollongong, Byron Bay and Brisbane, we found huge scars where sediment had collapsed, forming submarine landslides up to several tens of kilometres across.

A portion of the continental slope looking onshore towards Brisbane, showing the ‘eaten away’ appearance of the slope in the northern two-thirds of the image, the result of previous submarine landslides.
Samantha Clarke

What are submarine landslides?

Submarine landslides, as the name suggests, are underwater landslides where seafloor sediments or rocks move down a slope towards the deep seafloor. They are caused by a variety of different triggers, including earthquakes and volcanic activity.

The typical evolution of a submarine landslide after failure.
Geological Digressions

As we processed the incoming data to our vessel, images of the seafloor started to become clear. What we discovered was that an extensive region of the seafloor offshore New South Wales and Southern Queensland had experienced intense submarine landsliding over the past 15 million years.

From these new, high-resolution images, we were able to identify over 250 individual historic submarine landslide scars, a number of which had the potential to generate a tsunami. The Byron Slide in the image below is a good example of one of the “smaller” submarine landslides we found – at 5.6km long, 3.5km wide, 220m thick and 1.5 cubic km in volume. This is equivalent to almost 1,000 Melbourne Cricket Grounds.

This image shows the Byron Slide scar, located offshore Byron Bay.
Samantha Clarke

The historic slides we found range in size from less than 0.5 cubic km to more than 20 cubic km – the same as roughly 300 to 12,000 Melbourne Cricket Grounds. The slides travelled down slopes that were less than 6° on average (a 10% gradient), which is low in comparison to slides on land, which usually fail on slopes steeper than 11°.

We found several sites with cracks in the seafloor slope, suggesting that these regions may be unstable and ready to slide in the future. However, it is likely that these submarine landslides occur sporadically over geological timescales, which are much longer than a human lifetime. At a given site, landslides might happen once every 10,000 years, or even less frequently than this.

A collection of submarine landslide scars off Moreton Island.
Samantha Clarke

Since returning home, our investigations have focused on how, when, and why these submarine landslides occur. We found that east Australia’s submarine landslides are unexpectedly recent, at less than 25,000 years old, and relatively frequent in geological terms.

We also found that for a submarine landslide to generate along east Australia today, it is highly likely that an external trigger is needed, such as an earthquake of magnitude 7 or greater. The generation of submarine landslides is associated with earthquakes from other places in the world.

Submarine landslides can lead to tsunamis ranging from small to catastrophic. For example, the 2011 Tohoku tsunami resulted in more than 16,000 individuals dead or missing, and is suggested to be caused by the combination of an earthquake and a submarine landslide that was triggered by an earthquake. Luckily, Australia experiences few large earthquakes, compared with places such as New Zealand and Peru.

Why should we care about submarine landslides?

We are concerned about the hazard we would face if a submarine landslide were to occur in the future, so we model what would happen in likely locations. Modelling is our best prediction method and requires combining seafloor maps and sediment data in computer models to work out how likely and dangerous a landslide threat is.

Our current models of tsunamis generated by submarine landslides suggest that some sites could represent a future tsunami risk for Australia’s east coast. We are currently investigating exactly what this threat might be, but we suspect that such tsunamis pose little to no immediate threat to the coastal communities of eastern Australia.

This video shows an animation of a tsunami caused by submarine landslide.

That said, submarine landslides are an ongoing, widespread process on the east Australian continental slope, so the risk cannot be ignored (by scientists, at least).

Of course it is hard to predict exactly when, where and how these submarine landslides will happen in future. Understanding past and potential slides, as well as improving the hazard and risk evaluation posed by any resulting tsunamis, is an important and ongoing task.

The ConversationIn Australia, more than 85% of us live within 50km of the coast. Knowing what is happening far beneath the waves is a logical next step in the journey of scientific discovery.

Samantha Clarke, Associate Lecturer in Education Innovation, University of Sydney; Hannah Power, Lecturer in Coastal Science, University of Newcastle; Kaya Wilson, , University of Newcastle, and Tom Hubble, Associate professor, University of Sydney

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

Sustainable shopping: how to buy tuna without biting a chunk out of the oceans



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Canned tuna is an Australian pantry staple.
NOAA

Candice Visser, University of Wollongong and Quentin Hanich, University of Wollongong

Shopping can be confusing at the best of times, and trying to find environmentally friendly options makes it even more difficult. Welcome to our Sustainable Shopping series, in which we ask experts to provide easy eco-friendly guides to purchases big and small.


Tuna is the most popular canned fish eaten in Australia and one of the most popular fish produced worldwide. The total catch of tuna in 2013 was about 7.4 million tonnes.

Tuna is a massive industry and most of this catch ends up in cans. But while each can of tuna might look similar, the environmental impacts of different brands vary. So, with a sea of “eco-friendly” labels and choices, how do you know which is the most sustainable?


Read more: Australian endangered species – Southern Bluefin Tuna


Almost all Australian canned tuna is imported

Australia produces large amounts of high-end seafood such as rock lobster, abalone and fresh tuna, but most of this doesn’t end up in our supermarkets – it is exported to countries willing to pay more. Instead, roughly 70% of all seafood eaten in Australia is imported. Most of this includes lower-value products such as frozen fish, frozen prawns and canned tuna.

Cans of tuna line the supermarket shelves. Which one is the choice for the sustainable shopper?
www.shutterstock.com

Australia is a major market for canned tuna. Almost all of the canned tuna sold here comes from Thailand, which processes about half of the world’s tuna supply. It is now almost impossible to buy Australian-produced canned tuna since large-scale production in Australia ended in May 2010.

While it is not unusual for a developed country to import large amounts of seafood, Australia is failing to meet international standards for sustainable seafood trade. Australia has strict requirements for seafood exports, but seafood imports are largely unregulated. This means it can be difficult to know if the imported seafood you buy was caught sustainably or even legally.

Catching 7.4 million tonnes of tuna

High global demand drives unsustainable fishing practices. These practices include overfishing, issues related to bycatch (which is the accidental catch of other marine animals like dolphins, turtles and seabirds), and “illegal, unregulated and unreported” (IUU) fishing. Now, 77% of the world’s fisheries are fished at their limit or beyond.

Of the many different types of tuna species, skipjack tuna is the most sustainable option.
FAO

Unsustainable fishing practices have devastating effects on the health of the marine ecosystem and the livelihoods of fishers. With this in mind, it is more important than ever to know about the origin of your fish.

Some species of tuna are fished at sustainable rates, whereas others are overfished. The most common species that end up in cans are skipjack and yellowfin tuna. Both of these species have sustainable stocks in the Western and Central Pacific Ocean (WCPO). Skipjack also has sustainable stocks in the Indian Ocean. Higher-value species such as bigeye and bluefin varieties are usually reserved for sushi and sashimi markets. Southern bluefin tuna is overfished and is listed as critically endangered by the IUCN.


Read more: Australian endangered species: southern bluefin tuna


The type of catch matters

The most sustainable fishing methods for tuna are “pole-and-line” and “FAD-free purse seine”. However, each method has a catch.

Pole-and-line fishing is used to catch tuna species one fish at a time.
Paul Hilton/Wikimedia Commons, CC BY-SA

Pole-and-line fishing is the traditional method of using a pole, line and hook to catch fish. The rate of bycatch is small because fishers can catch and release non-tuna species. However, bait fish are used to attract the tuna, which can have a large impact if the bait fish is not caught in a sustainable way. Due to the labour-intensive nature of pole-and-line fishing and dependence on bait fish, this method makes up only a small proportion of the total tuna caught and is unable to supply tuna in large amounts.

Purse seine catches tuna by surrounding them with a net and hauling the catch up to the ship. When a FAD device is used, bycatch can also be caught.
FAO

Purse seine fisheries use a large net to surround a school of fish. In recent years purse seiners have increasingly used fish aggregating devices (FAD) to attract tuna and increase their efficiency. However, FADs also attract bycatch and juvenile tuna and are poorly regulated. Therefore, only purse seine fisheries that set on free-swimming schools of tuna are considered sustainable.

Quick guide to better tuna

Quick guide: The right can of tuna.
Author provided

What can you do?

1. Read the label

Examine the details on the back of the can for tuna species, fishing method and catch location. There are sustainable options for each of these categories.

The best approach is to opt for skipjack before yellowfin or other tuna varieties. Next, choose tuna caught using “pole-and-line” or “FAD-free purse seine” before “longline” or “purse seine”. Then, check for tuna caught in the Western Central Pacific Ocean – this may appear on the can as FAO Nr. 71. If the can doesn’t at least identify the species or fishing method, it’s probably not worth your time.

2. Consider eco-labels over unverified self-claims

Eco-labels and eco-claims often feature prominently on tuna cans. Eco-labels are market-based tools used to promote sustainable practices. Decoding them can seem challenging, but it doesn’t have to be.

Dolphin-safe labels only focus on the impacts of fishing on dolphins.
NOAA

First, it is important to recognise that a dolphin-safe label is not a sustainability label. It focuses only on the impacts of fishing on dolphins. Dolphin-safe doesn’t consider tuna catch levels or other socio-environmental impacts. Most importantly, it doesn’t require independent third-party verification.

In contrast, some newer eco-labels consider a wider set of impacts including target species stock levels, impact on other species and even the social impact on fishers – such as fair pay and work conditions.

So far, MSC is the only label to be recognised by the Global Sustainable Seafood Initiative (GSSI), but keep in mind this label is not without criticism.

Look for MSC certification that is sustainable and eco-friendly.
deckhand/flickr, CC BY-NC-ND

In recent months, the MSC-certified Pasifical brand has been criticised because its FAD-free purse seine sourced tuna are transported on vessels that can also catch FAD-caught purse seine tuna. Some commentators argue that this enables unsustainable FAD-caught fisheries to continue operating.

On the other hand, MSC has the strongest chain of custody. It can trace every can of tuna from the supermarket shelf all the way back to the fishery. It’s not clear whether the original criticism was driven by competition for supermarket shelf space, as some industry insiders have claimed.


Read more: Here’s why your sustainable tuna is also unsustainable


3. Download seafood guides

Various online guides are also available to help consumers choose sustainable seafood options. These guides rank and recommend seafood using a stoplight system. The recommendations are based on available scientific research or a defined set of criteria.

In Australia, Greenpeace publishes a Canned Tuna Guide that ranks available brands. Australia’s Sustainable Seafood Guide provides recommendations for seafood generally.

Guides are also produced by Monterey Bay Aquarium Seafood Watch for the US, Ocean Wise for Canada and WWF’s Fish Forward Project for South Africa and several countries in the EU and Asia.

4. Future technologies, supply chains and transparency

While the steps above assist with making sustainable seafood choices, it doesn’t help if the fish you’re buying has been mislabelled. There is still uncertainty related to transparency and traceability in the supply chain.

To help combat this problem, Coles has partnered with WWF to ensure the seafood it sells is sustainably sourced. Aldi has also introduced an initiative called “Trace Your Tuna” to link tuna to its catch location.

New applications that use tracking data are also developing. Apps are available that scan QR codes and barcodes to provide consumers with extra information about the origins of lots of different products including seafood. These include Oziris in Australia, ThisFish in Canada and the Seafood Traceability System offered by the Korean government.

Simultaneously, new initiatives such as Global Fishing Watch are providing open access to vessel movement data, providing tremendous opportunities for transparency and traceability.

The ConversationIn short, the easiest way to make a sustainable choice when buying canned tuna is to check the contents label and look for a credible eco-label. If you have a little more time, it might be worthwhile to check out seafood recommendation guides or to download a product tracking app on your smartphone.

Candice Visser, PhD Candidate, University of Wollongong and Quentin Hanich, Associate Professor, University of Wollongong

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

Drought on the Murray River harms ocean life too



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The mouth of the Murray River delivers vital nutrients to marine life in the ocean beyond.
SA Water, Author provided

Hannah Auricht, University of Adelaide and Kenneth Clarke, University of Adelaide

Drought in the Murray River doesn’t just affect the river itself – it also affects the ecosystems that live in the ocean beyond.

In a study published in Marine and Freshwater Research today, we found that the very low flows in the river over the past decade reduced the abundance of microscopic marine plants called phytoplankton, which are ultimately the base of all marine food webs.

This shows that the health of the Murray River has a much bigger influence on the marine environment than we previously realised. With climate change poised to make droughts more frequent and severe in the river, it will be crucial to monitor the health not just of freshwater species, but of the local marine ones too.


Read more: Is the Murray-Darling Basin Plan broken?


Phytoplankton depend on nutrients, which are often delivered to the ocean by rivers. In turn, these tiny plants are a source of food for almost all marine ecosystems. Worldwide, they are responsible for half the production of organic matter on the planet.

In South Australia, a dry period dubbed the Millennium Drought (2001 to 2010) and overallocation of water resources (primarily for agriculture) meant that very little water was delivered from the Murray Mouth to the coastal ocean. Between 2007 and 2010, no water was discharged at all. The water in the river’s lower reaches became much saltier and cloudier.

We used historical flow records and satellite imagery, taken between early 2002 and late 2016, to figure out how much phytoplankton and other organic matter were in the coastal ocean each month. We broke up the area into incremental zones, venturing up to 130km from the river mouth.

We found that during and after high-flow events, Murray River discharge resulted in a huge increase in phytoplankton concentrations – as far as 60km beyond the river’s mouth. Surprisingly, before our research it wasn’t known that the river played such an important role in stimulating phytoplankton growth over such a large area.

The mouth of the Murray River, where sometimes no water flows into the ocean at all.
CSIRO/Wikimedia Commons, CC BY

Armed with an understanding of how river flows influenced phytoplankton growth, we used historic flow records to estimate phytoplankton concentrations back to 1962. Our results showed that large flows used to occur more often and in greater volumes, and consequently that phytoplankton populations would have gone through more frequent and larger booms.

This in turn would have benefited all of the species that ultimately depend on phytoplankton for food, either directly or indirectly. This food web encompasses almost the whole marine ecosystem.

The past affects the future

Water resource management has greatly altered the volume and timing of freshwater discharges from the Murray. The ocean beyond the Murray mouth now receives small and infrequent deliveries of freshwater.

Rainfall and streamflow are decreasing in this already variable region, while temperatures are rising. This means that South Australia is likely to experience more severe and more frequent droughts, which will cause flows from the Murray mouth to decline still further, ultimately reducing phytoplankton abundance.

Previous research had already established the links between river outflows, phytoplankton and health of marine environments and species. But as far as we can tell, no other research has looked at exactly how extended periods of no or low river outflows affect marine ecosystems. This makes it difficult to predict how these systems will respond to climate change.

We believe that reduced Murray River outflows and reduced phytoplankton concentrations would likely have also placed strain on local mulloway fish and Goolwa cockle populations. Juvenile mulloway use river outflows as habitat and environmental cues, and cockles feed on organic material in the water.


Read more: ‘Tax returns for water’: how satellite-audited statements can save the Murray-Darling


This is why it is so important that the management of the Murray River doesn’t just stop at the river’s mouth, but continues into the ocean beyond. Current plans are focused on restoring flows to support the riparian and wetland ecosystems of the Murray as well as the Lower Lakes and Coorong.

But there has been little recognition of the role of river outflows on the marine environment – let alone in management. Although we might not always think about it, the marine environment is really the end of the river system, and part of a larger global cycle. It would therefore be beneficial if plans extend to monitor the marine ecosystem’s response, both at broad and fine scales, to varying flow events.

The ConversationIt would seem the time is past ripe to call for greater research and consideration on this matter, so that we don’t do further damage to what is actually still a part of the Murray River system, and can improve measures to protect the marine environment.

Hannah Auricht, PhD candidate, University of Adelaide and Kenneth Clarke, Researcher, School of Biological Sciences, University of Adelaide

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

China’s growing footprint on the globe threatens to trample the natural world



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A Chinese road-building corporation felling rainforest in the Congo Basin.
Bill Laurance, Author provided

Bill Laurance, James Cook University

Many observers of China’s escalating global program of foreign investment and infrastructure development are crossing their fingers and hoping for the best. In an ideal world, China’s unbridled ambitions will improve economic growth, food security and social development in many poor nations, as well as enriching itself.

Such hopes are certainly timely, given the isolationism of the US Trump
administration, which has created an international leadership vacuum that China is eager to fill.

But a close look reveals that China’s international agenda is far more exploitative than many realise, especially for the global environment. And the Chinese leadership’s claims to be embracing “green development” are in many cases more propaganda than fact.


Read more: China will need to be more transparent to achieve its development goals


To help steer through the maze, I provide here a snapshot of China’s present environmental impacts. Are China’s assertions reasoned and defensible, or something else altogether?

Predatory force?

For a start, China is overwhelmingly the world’s biggest consumer of illegally poached wildlife and wildlife products. From rhino horn, to pangolins, to shark fins, to a menagerie of wild bird species, Chinese consumption drives much of the global trade in wildlife exploitation and smuggling.

Over the past 15 years, China’s rapacious appetite for ivory has largely driven a global collapse of elephant populations. In response to growing international criticism, China promised to shut down its domestic ivory trade by the end of 2017.

The author examining a Forest Elephant gunned down by ivory poachers in central Africa.
Mahmoud Mahmoud

But even before China’s ban has taken full force, a black market for ivory is developing in neighbouring Laos. There, Chinese entrepreneurs are churning out great quantities of carved ivory products, specifically designed for Chinese tastes and openly sold to Chinese visitors.

China is also the world’s biggest importer of illegal timber, a trade that imperils forests while defrauding developing nations of billions of dollars each year in timber royalties.

China claims to be working to reduce its illegal timber imports, but its efforts are half-hearted at best, judging by the amount of illegal timber still flowing across its border with Myanmar.

A queue of logging trucks in Southeast Asia.
Jeff Vincent

Infrastructure tsunami

More damaging still are China’s plans for infrastructure expansion that will irreparably degrade much of the natural world.

China’s One Belt One Road initiative alone will carve massive arrays of new roads, railroads, ports, and extractive industries such as mining, logging, and oil and gas projects into at least 70 nations across Asia, Europe, and Africa.

A partial representation of China’s One Belt One Road scheme, circa 2015.
Mercator Institute for China Studies

Chinese President Xi Jinping promises that the Belt and Road initiative will be “green, low-carbon, circular and sustainable”, but such a claim is profoundly divorced from reality.

As my colleagues and I recently argued in Science and Current Biology, the modern infrastructure tsunami that is largely being driven by China will open a Pandora’s box of environmental crises, including large-scale deforestation, habitat fragmentation, wildlife poaching, water pollution and greenhouse gas emissions.

China’s pursuit of natural resources is also escalating across Latin America. In the Amazon, for example, big mining projects – many of which are feeding Chinese industries – don’t just cause serious local degradation, but also promote widespread deforestation from the networks of roads bulldozed into remote areas to access the mines.

Why roads are so dangerous for nature.

Overall, China is the most aggressive consumer of minerals on the planet, and the biggest driver of tropical deforestation.

Beyond this, China is pushing to build a 5,000km railroad across South America, to make it cheaper for China to import timber, minerals, soy and other natural resources from ports along South America’s Pacific coast. If it proceeds, the number of critical ecosystems that would be impacted by this project is staggering.

A World Bank study of more than 3,000 overseas projects funded or operated by China revealed how it often treats poor nations as “pollution havens” – transferring its own environmental degradation to developing nations that are desperate for foreign investment.

Finally, much has been made of the fact that China is beginning to temper its appetite for domestic fossil-fuelled energy. It is now a leading investor in solar and wind energy, and recently delayed construction of more than 150 coal-fired electricity plants in China.

These are unquestionably pluses, but they need to be seen in their broad context. In terms of greenhouse-gas emissions, China has exploded past every other nation. It now produces more than twice the carbon emissions of the United States, the second-biggest polluter, following the greatest building spree of coal, nuclear, and large-scale hydro projects in human history.

Despite its new post-Trump role as the world’s de facto climate leader, China’s overall agenda could scarcely be described as green.

A tiger relaxes along a grassy bank.
Matt Gibson/Shutterstock

Iceberg ahead

Some would say it’s unfair to criticise China like this. They would argue that China is merely following a well-trodden path of exploitative development previously forged by other nations and colonial powers.

But China is not the same as any other nation. The astounding growth and size of its economy, its dangerously single-minded vision for exploiting natural resources and land internationally, its intolerance of internal and external criticism, and its increasingly closed media and official myopia all combine to make it unique.


Read more: Developing countries can prosper without increasing emissions


President Xi admits that many Chinese corporations, investors and lenders operating overseas have often acted aggressively and even illegally overseas. But he says his government is powerless to do much about it. The most notable government response to date is a series of “green papers” containing guidelines that sound good in theory but are almost universally ignored by Chinese interests.

Indigenous forest people in the Congo Basin become increasingly poor and marginalised as foreign miners, loggers and poachers invade their lands.
Mahmoud Mahmoud

Are Xi’s assertions of powerlessness believable? He increasingly rules China with an iron hand. Is it really impossible for China to guide and control its overseas industries, or are they simply so profitable that the government doesn’t want to?

The ConversationOf course, China’s huge international ambitions will have some positive effects, and could even be economically transformative for certain nations. But many other elements will benefit China while profoundly damaging our planet.

Bill Laurance, Distinguished Research Professor and Australian Laureate, James Cook University

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

All hail new weather radar technology, which can spot hailstones lurking in thunderstorms


Joshua Soderholm, The University of Queensland; Alain Protat, Australian Bureau of Meteorology; Hamish McGowan, The University of Queensland; Harald Richter, Australian Bureau of Meteorology, and Matthew Mason, The University of Queensland

An Australian spring wouldn’t be complete without thunderstorms and a visit to the Australian Bureau of Meteorology’s weather radar website. But a new type of radar technology is aiming to make weather radar even more useful, by helping to identify those storms that are packing hailstones.

Most storms just bring rain, lightning and thunder. But others can produce hazards including destructive flash flooding, winds, large hail, and even the occasional tornado. For these potentially dangerous storms, the Bureau issues severe thunderstorm warnings.

For metropolitan regions, warnings identify severe storm cells and their likely path and hazards. They provide a predictive “nowcast”, such as forecasts up to three hours before impact for suburbs that are in harm’s way.


Read more: To understand how storms batter Australia, we need a fresh deluge of data


When monitoring thunderstorms, weather radar is the primary tool for forecasters. Weather radar scans the atmosphere at multiple levels, building a 3D picture of thunderstorms, with a 2D version shown on the bureau’s website.

This is particularly important for hail, which forms several kilometres above ground in towering storms where temperatures are well below freezing.

Bureau of Meteorology 60-minute nowcast showing location and projected track of severe thunderstorms in 10-minute steps.
Australian Bureau of Meteorology

In terms of insured losses, hailstorms have caused more insured losses than any other type of severe weather events in Australia. Brisbane’s November 2014 hailstorms cost an estimated A$1.41 billion, while Sydney’s April 1999 hailstorm, at A$4.3 billion, remains the nation’s most costly natural disaster.

Breaking the ice

Nonetheless, accurately detecting and estimating hail size from weather radar remains a challenge for scientists. This challenge stems from the diversity of hail. Hailstones can be large or small, densely or sparsely distributed, mixed with rain, or any combination of the above.

Conventional radars measure the scattering of the radar beams as they pass through precipitation. However, a few large hailstones can look the same as lots of small ones, making it hard to determine hailstones’ size.

A new type of radar technology called “dual-polarisation” or “dual-pol” can solve this problem. Rather than using a single radar beam, dual-pol uses two simultaneous beams aligned horizontally and vertically. When these beams scatter off precipitation, they provide relative measures of horizontal and vertical size.

Therefore, an observer can see the difference between flatter shapes of rain droplets and the rounder shapes of hailstones. Dual-pol can also more accurately measure the size and density of rain droplets, and whether it’s a mixture or just rain.

Together, these capabilities mean that dual-pol is a game-changer for hail detection, size estimation and nowcasting.

Into the eye of the storm

Dual-pol information is now streaming from the recently upgraded operational radars in Adelaide, Melbourne, Sydney and Brisbane. It allows forecasters to detect hail earlier and with more confidence.

However, more work is needed to accurately estimate hail size using dual-pol. The ideal place for such research is undoubtedly southeast Queensland, the hail capital of the east coast.

When it comes to thunderstorm hazards, nothing is closer to reality than scientific observations from within the storm. In the past, this approach was considered too costly, risky and demanding. Instead, researchers resorted to models or historical reports.

The Atmospheric Observations Research Group at the University of Queensland (UQ) has developed a unique capacity in Australia to deploy mobile weather instrumentation for severe weather research. In partnership with the UQ Wind Research Laboratory, Guy Carpenter and staff in the Bureau of Meteorology’s Brisbane office, the Storms Hazards Testbed has been established to advance the nowcasting of hail and wind hazards.

Over the next two to three years, the testbed will take a mobile weather radar, meteorological balloons, wind measurement towers and hail size sensors into and around severe thunderstorms. Data from these instruments provide high-resolution case studies and ground-truth verification data for hazards observed by the Bureau’s dual-pol radar.

Since the start of October, we have intercepted and sampled five hailstorms. If you see a convoy of UQ vehicles heading for ominous dark clouds, head in the opposite direction and follow us on Facebook instead.

UQ mobile radar deployed for thunderstorm monitoring.
Kathryn Turner

Unfortunately, the UQ storm-chasing team can’t get to every severe thunderstorm, so we need your help! The project needs citizen scientists in southeast Queensland to report hail through #UQhail. Keep a ruler or object for scale (coins are great) handy and, when a hailstorm has safely passed, measure the largest hailstone.

Submit reports via uqhail.com, email, Facebook or Twitter. We greatly appreciate photos with a ruler or reference object and approximate location of the hail.

How to report for uqhail.

Combining measurements, hail reports and the Bureau of Meteorology’s dual-pol weather radar data, we are working towards developing algorithms that will allow hail to be forecast more accurately. This will provide greater confidence in warnings and those vital extra few minutes when cars can be moved out of harm’s way, reducing the impact of storms.


Read more: Tropical thunderstorms are set to grow stronger as the world warms


Advanced techniques developed from storm-chasing and citizen science data will be applied across the Australian dual-pol radar network in Sydney, Melbourne and Adelaide.

The ConversationWho knows, in the future if the Bureau’s weather radar shows a thunderstorm heading your way, your reports might even have helped to develop that forecast.

Joshua Soderholm, Research scientist, The University of Queensland; Alain Protat, Principal Research Scientist, Australian Bureau of Meteorology; Hamish McGowan, Professor, The University of Queensland; Harald Richter, Senior Research Scientist, Australian Bureau of Meteorology, and Matthew Mason, Lecturer in Civil Engineering, The University of Queensland

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