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MELTING ANTARCTICA: The Totten Glacier in East Antarctica has an unstable area that could collapse and contribute to more than two metres of sea level rise if climate change remains unchecked, say researchers.

The Great Barrier Reef's health has declined in recent years Reef image from www.shutterstock.com

The Great Barrier Reef has been in the spotlight thanks to severe coral bleaching since March, leaving only 7% of the reef untouched. The bleaching, driven by record-breaking sea temperatures, has been linked to human-caused climate change.

Apart from bleaching, the reef is in serious trouble thanks to a variety of threats. Many species and ecosystems of the Great Barrier Reef are in serious decline.

It is now overwhelmingly clear that we need to fix these problems to give the reef the best chance in a warming world. In fact, the upcoming election is arguably our last chance to put in place a plan that will save the reef.

In a recent paper, we estimate that we need to spend A$10 billion over the next ten years - about five times as much as current state and federal governments are spending – to fix up reef water quality before climate change impacts overwhelm it.

Stop water pollution

Poor water quality is one of the major threats to the Great Barrier Reef. Sediment and nutrients (such as nitrogen) washed by rivers onto the reef cause waters to become turbid, shutting out light for corals and seagrass. It can also encourage algal growth and outbreaks of coral-eating crown-of-thorns starfish.

The Queensland and Australian governments have made plans with targets to improve water quality, but the main plan - the Reef 2050 Long Term Sustainability Plan – is completely inadequate according to the Australian Academy of Science. Its targets are unlikely to be met. And others have suggested ways to improve water quality on the Great Barrier Reef.

To provide resilience for the Great Barrier Reef against the current and rapidly increasing climate impacts, water quality management needs to be greatly improved by 2025 to meet the targets and guidelines. 2025 is important as it’s likely that climate change effects will be overwhelming after that date. It is also the target date for the Reef 2050 Long Term Sustainability Plan.

What needs to be done

In our recent article, we analysed what we need to do to respond to the current crisis, especially for water quality.

1. Refocus management to the “Greater Great Barrier Reef (GBR)” – that is, include management of Torres Strait, Hervey Bay and river catchments that run into the reef as priorities along with the world heritage area. This area is shown in figure above.

2. Prioritise management for ecosystems in relatively good condition, such Torres Strait, northern Cape York and Hervey Bay which have the highest current integrity. These areas should still be prioritised despite the recent severe bleaching in the northern Great Barrier Reef.

3. Investigate methods of cross-boundary management to achieve simultaneous cost-effective terrestrial, freshwater and marine ecosystem protection in the Greater GBR.

4. Develop a detailed, comprehensive, costed water quality management plan for the Greater GBR. In the period 2009-16, more than A$500 million was spent on water quality management (with some success) without a robust comprehensive plan to ensure the most effective use of the funding.

5. Use existing federal legislation (the Great Barrier Reef Marine Park Act and the Environment Protection and Biodiversity Conservation Act) to regulate catchment activities that lead to damage to the Greater GBR, together with the relevant Queensland legislation. These rules were established long ago and are immediately available to tackle terrestrial pollutant discharge.

6. Fund catchment and coastal management to the required level to largely solve the pollution issues for the Greater GBR by 2025, to provide resilience for the system in the face of accelerating climate change impacts. The funding required is large – of the order of A$1 billion per year over the next ten years but small by comparison to the worth of the Great Barrier Reef – estimated to be of the order of A$20 billion per year.

7. Continue enforcement of the zoning plan.

8. Show commitment to protecting the Greater GBR through greenhouse gas emissions control, of a scale to be relevant to protecting the reef (for example those proposed by the Climate Change Authority), by 2025.

Unless immediate action is taken to improve water quality, the onset of accelerating climate change impacts mean there is little chance the current decline in reef health can be prevented.

Jon Brodie has received funding over the last two years from the Australian Government, the Queensland Government, Natural Resource Management groups, WWF, UNEP, Melbourne Water, NSW EPA.

Richard Pearson has in the past received funding from the Australian Government through the Australian Research Council and the Marine and Tropical Science Research Facility. He is a member of ACF.

New mapping of one of the most remote areas in Antarctica has revealed regions deep within Earth’s largest ice sheet that are particularly prone to rapid melting.

Our study, published today in Nature, is focused on East Antarctica’s Totten Glacier, the outlet for the world’s largest ice catchment. The results suggest that if rising global temperatures trigger the glacier to retreat rapidly – as has happened previously in its history – this region alone could deliver sea-level rises of well over a metre over the ensuing centuries.

The Totten Glacier region is a key area for understanding the long-term vulnerability of the Antarctic Ice Sheet, but until now, knowledge of this region’s glacial history has been very limited.

Our study shows that, although the region near the coast is quite stable on timescales of several millennia, regions further inland have potential for significant and rapid retreat as the climate warms.

Specifically, we identified two stable zones where the ice sheet is not prone to rapid collapse, and two unstable zones, where it is. We have also discovered that transitions between these states have happened repeatedly during the life of the ice sheet.

Stable and not so stable

As part of the international ICECAP project, my colleagues and I used ice-penetrating radar, as well as magnetic and gravity data, to chart the rocks beneath the glacier.

By mapping the shape of the ice-sheet and its base, as well as the thickness of the rocks and sediments beneath, we were able to study the characteristic patterns of erosion left behind by the ice sheet’s previous advances and retreats – thus revealing the ice sheet’s past behaviour.

The observed patterns suggest that the ice sheet has spent much of its history in one of two configurations: either the edge has been close to the current Antarctic coast (within 150 kilometres); or it has been located some 350-550 kilometres inland. In either of these states, the ice would be relatively stable, with this glacier providing sea level fluctuations of less than a metre over the course of glacial cycles.

But the pattern of erosion also shows that melting has periodically forced the ice sheet out of either of these stable states, causing the ice sheet to collapse and retreat far inland. These events might have typically driven up global sea levels by 1.3-1.4 metres over the course of a few centuries.

What is happening today?

Previous studies from satellite data have indicated that the coastal part of the Totten Glacier region and its floating ice shelf are melting rapidly. Last year, the ICECAP team discovered that there is currently warm water circulating underneath a floating portion of the glacier that is causing more melting than might have been expected.

Our results show that following a rapid loss of coastal ice due to the collapse of the floating ice shelf, this region is likely to respond more slowly than other parts of Antarctica to warming temperatures, due to the existence of a “stable zone”.

But as temperatures continue to increase, this glacier is likely to retreat into the unstable zone, and make a rapid and proportionally greater contribution to sea levels.

Our ice sheet modelling suggests that while the Totten region is not the first region in Antarctica to respond to warming climate, it is likely to become progressively more unstable as warming proceeds over hundreds to thousands of years. Ultimately this region could become the “fat end of the wedge” in terms of Antarctica’s overall contribution to rising seas, accounting for almost 15% of Antarctica’s total contribution to sea-level rise. This is likely to happen while other regions have become ice-free, or are stabilising after periods of rapid ice loss.

Our results suggest that the Totten region has severe implications for global sea level rise in warming climate conditions, especially once warming reaches the critical thresholds likely to tip the glacier out of its stable states. Given the long timescales involved for ice-sheet melting it is difficult to say with confidence when this tipping point might be reached.

Increases to carbon dioxide levels today will commit us to temperature increases that persist for thousands of years. The upper limit of the coastal stable zone could be crossed under conditions similar to those predicted for the next century, based on the higher emissions scenarios envisaged by the Intergovernmental Panel on Climate Change.

Alan Aitken receives research funding from the Australian Research Council, the Science and Industry Endowment Fund and the State Government of Western Australia. These funding sources relate to other projects. His contribution to this work was funded by the University of Western Australia's Goodeve Foundation.

Grizzly bears in Alaska and Canada are moving north as their environment warms, bringing them into contact with polar bears located on the coastline

Climate change is known for swelling the oceans and fueling extreme weather, but it may be also causing the curious emergence of a new type of bear in the Arctic.

A bear shot in the frigid expanse of northern Canada is believed to be a grizzly-polar bear hybrid, a consequence of the increasing interactions between the two imposing bear species.

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Country’s low emissions action plan cannot be undone even by a Donald Trump presidency, but it may put global cooperation on climate change at risk

The US would still meet its obligations under the Paris accord on climate change if Donald Trump were elected president, a senior US administration official has told the Guardian.

He said the path of the US towards a lower-carbon economy was already set, and was dependent on market forces that would not easily succumb to political tinkering.

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Women now hold six of the most influential positions at global climate talks, but can they make a difference on the ground? Climate Home reports

Whisper it quietly, but a gender revolution is taking place at the global climate change negotiations.

As of 17 May, the six most influential positions within the UN process are all held by women, a significant increase on last year’s total of two.

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Thanks to the great western commons, which the Bundys and their legislative champions would like to dismantle, all Americans still enjoy the freedom to roam on some of the most spectacular lands on the planet

It goes without saying that in a democracy, everyone is entitled to his or her own opinions. The trouble starts when people think they are also entitled to their own facts.

Away out west, on the hundreds of millions of acres of public lands that most Americans take for granted (if they are aware of them at all), the trouble is deep, widespread, and won’t soon go away. Last winter’s armed takeover and 41-day occupation of Malheur national wildlife refuge in south-eastern Oregon is a case in point. It was carried out by people who, if they hadn’t been white and dressed as cowboys, might have been called “terrorists” and treated as such. Their interpretation of the history of western lands and of the judicial basis for federal land ownership – or at least that of their leaders, since they weren’t exactly a band of intellectuals – was only loosely linked to reality.

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The ability to cooperate and coordinate will mean the difference between looking forward with hope to the future or facing catastrophic climate change

In 1972 the law was passed that allowed the UK to join what was then called the European Economic Community (EEC). Despite Europe’s current crises, it’s unchanging, fundamental challenge was expressed that year by Sicco Mansholt, then president of the European commission, probably better than by any of the current voices in the referendum campaign, whether for or against UK remaining in.

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Zero emission milestone reached as country is powered by just wind, solar and hydro-generated electricity for 107 hours

Portugal kept its lights on with renewable energy alone for four consecutive days last week in a clean energy milestone revealed by data analysis of national energy network figures.

Electricity consumption in the country was fully covered by solar, wind and hydro power in an extraordinary 107-hour run that lasted from 6.45am on Saturday 7 May until 5.45pm the following Wednesday, the analysis says.

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Look inside a life-size model of a submarine which the Chinese hope will take humans to the very bottom of the ocean - the Mariana Trench, in the Pacific.

Deep underground, beneath Daya Bay in the south of China, scientists are hunting for the oddest particles in the cosmos - neutrinos.

Government plans to fell Poland’s Białowieża forest have divided families, led to death threats against green campaigners and allegations of an ‘environmental coup’ by government and state timber interests

Europe’s last primeval forest is facing what campaigners call its last stand as loggers prepare to start clear-cutting trees, following the dismissal of dozens of scientists and conservation experts opposed to the plan.

Poland’s new far right government says logging is needed because more than 10% of spruce trees in the Unesco world heritage site of Białowieża are suffering from a bark beetle outbreak. But nearly half the logging will be of other species, according to its only published inventory.

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The Greens were not invited to an election debate over the environment and climate change, and they're not altogether pleased about it.

More than 30 green groups sign statement after damning report says extending regional forestry agreements ‘would constitute an irrational decision on environmental, economic and social grounds’

More than 30 environmental groups have signed a statement demanding that agreements allowing the logging of Australian native forests not be renewed.

Australia’s 10 regional forestry agreements (RFAs) were signed between 1997 and 2001, each running for 20 years, with the first two expiring in 2017.

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SOCIAL NETWORKS: There is a limit to how many people you can have in your social network - now a study reveals why, and how many relationships you need to maintain that network.

The records keep on falling Thermometer image from www.shutterstock.com

We’re not even halfway through the year but already you may have heard talk of 2016 being the hottest on record. But how can scientists be so sure we’re going to beat the previous record, set just last year?

Even before the end of 2015, the UK Met Office was forecasting with 95% confidence that 2016 would beat the record. Since then, that confidence has grown still further, as record after record has tumbled. April 2016 broke the record for the hottest April after we had experienced the hottest February and March on record already this year.

NASA climatologist Gavin Schmidt recently estimated at least a 99% likelihood of 2016 being hotter than 2015.

The role of El Niño

The main reason why scientists are so sure that 2016 will be the hottest year is El Niño, which is associated with warmer sea surface temperatures in the eastern Pacific Ocean. The 2015-16 El Niño was among the strongest on record and has increased global average temperatures.

Even though the El Niño is now decaying, the second year of a major El Niño event is often associated with much warmer than normal conditions and is typically warmer than the first.

For instance, the 1997-98 El Niño was by some measures the strongest on record, and contributed to 1998 becoming the hottest year on record globally at the time.

Since the start of this year, we have seen global temperature records smashed time and time again. This means that much colder temperatures for the second half of the year would be needed for 2016 not to surpass the 2015 record.

Even a strong La Niña event (the cooler opposite of El Niño), which some analysts are forecasting, is unlikely to produce cold enough temperatures.

One thing that could prevent 2016 becoming a record-breaking hot year is a major volcanic eruption in the tropics. Volcanic eruptions at low latitudes can eject aerosols high into the atmosphere reducing the amount of energy from the sun reaching the Earth’s surface.

Previous eruptions such as Pinatubo in 1991 and Tambora in 1815 (which caused 1816 to be “the year without a summer”) reduced temperatures across much of the globe.

However, it is the year after the eruption that often experiences the most severe cooling, so an eruption would have to be pretty soon and very strong to scupper 2016’s chances of being the hottest year on record.

What about climate change?

The role of climate change is smaller because we’re comparing 2016 with last year (the previous record). Over such short periods of time, the contribution from global warming doesn’t change much.

However, scientists estimated that 2015 was about 1℃ hotter than it would have been without human-caused climate change. As the human influence on the climate has not increased greatly since last year this 1℃ estimate will also apply to 2016.

The highly likely record temperature of 2016 will join the previous 17 record-breaking hot years back to 1937 which were all made more likely due to human-caused climate change (the rising global temperatures were even noticed as far back as 1938).

So even if El Niño is driving the 2016 record, we can say that the temperatures of this year (and indeed the temperatures associated with all the records over the last few years) would be virtually impossible without climate change.

An omen for the future?

We expect 2016 to beat the 2015 record for global average temperature as the decaying El Niño event pushes up surface temperatures.

This year, we’ve already seen devastating events associated with unusually warm temperatures, like the mass coral bleaching in the Great Barrier Reef, which has been largely attributed to human-induced climate change.

In future, we can expect to see more extreme heat events, like we’ve already seen in 2016, impacting society and ecosystems across the world.

And even though 2016 is likely to be the hottest year by some margin, we wouldn’t bet on this record lasting too long. While 2017 is very likely to be cooler due to a possible La Niña, with the strong warming trend the world’s experiencing it’s only a matter of time before we have another record-breaking hot year.

Only if we substantially reduce our greenhouse gas emissions now will we see the benefit of fewer record heat events in the future.

Andrew King receives funding from the ARC Centre of Excellence for Climate System Science.

Ed Hawkins receives funding from the Natural Environment Research Council (UK).

The fossil fuel industry, fee-hungry lawyers, banks and those that stay silent are profiting from the reef’s destruction. It’s time for them to say no more

It’s the worst crisis ever to hit the Great Barrier Reef and the extent of the devastation is only just coming to light. The reef is in the middle of the worst bleaching event ever seen, with unusually warm water killing as much as half the corals in the northern sections, with the trend set to continue for the next 20 years.

Who’s to blame for this destruction? And which businesses are profiting from the activities that are causing this havoc?

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Refugees are forced to flee conflict zones. They have no other choice unlike most migrants who leave their homes voluntarily to improve living conditions

She spent endless days and nights fleeing a warzone as a tiny child, first on foot through the darkness and then by boat after they shut the borders in her native Sierra Leone.

But when Yarrie Bangurra saw the camp she was supposed to be staying in, she couldn’t understand what it was her family had come to.

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EARLY LIFE: Seaweed-like fossils found in rocks in China dated to around 1.56 billion years ago are the earliest known examples of larger organisms made up of many cells built like our own.

For much of this year, up to 1,700 kilometres of the Murray River has been hit by a serious outbreak of potentially toxic blue-green algae, which has flourished in the hotter-than-average conditions. After three months, the river is now recovering with the arrival of wet weather. But we are unlikely to have seen the last of these poisonous microbes.

Large blue-green algal blooms are a relatively new phenomenon in inland waterways. In 1991 an algal bloom affected more than 1,000 km of the Darling River, the first time such an event had been reported in an Australian river, and one of the few times internationally. It was an environmental disaster, killing livestock and striking a telling blow against Australia’s reputation as a clean, green farming nation.

The response was decisive: a state of emergency was declared, and the bloom ultimately gave rise to significant investment by state and federal governments into freshwater research, particularly in the Murray-Darling Basin.

Why no emergency now?

Fast forward two and a half decades to the latest bloom afflicting the Murray River, one of Australia’s most socially, economically and culturally significant waterways. The past decade has seen four similar blooms on the Murray River: in 2007, 2009, 2010 and now. Yes, they have garnered press attention, but there has not been the same call to arms that we saw when the Darling River was struck in 1991.

It is almost as if such significant environmental events are now simply seen as the new normal. Why the apparent complacency?

The 2007, 2009 and 2010 algal blooms on the Murray River all happened during the Millennium Drought, and hence were probably ascribed to an aberration in the weather. In reality, the situation may have more to do with how we manage water in Australia – particularly during periods of scarcity, such as the one we may well be entering now.

Those three earlier events all started in Lake Hume, a large reservoir in the Murray River’s upper reaches, originally created in the 1930s to help “drought-proof” Australia. All of the blooms began after the water level was drawn down to below 10% of the lake’s capacity. At these low levels, disturbances (such as when transferring water between the Snowy River and Murray River systems) can easily lead to the mixing of warm surface waters (ideal for bloom formation) with nutrient-rich water at the bottom of the reservoir (ideal for feeding the bloom).

The resulting blooms were then released downstream into the Murray River by managed water releases from Lake Hume. The blooms most likely reformed in other constructed water bodies downstream – most notably Lake Mulwala, a shallow reservoir about 250 km along the river from Lake Hume.

Lake Mulwala’s principal purpose is to create hydraulic pressure to allow irrigation water to be diverted into farmland in southern New South Wales and northern Victoria. As a result, its shallow depth and mostly still waters make it an ideal incubator for blue-green algae.

The climate factor

This year’s algal bloom on the Murray River is different. The main blue-green alga in the current outbreak, Chrysosporium ovalisporum, has previously been reported in the river, but generally in very low numbers. It has never before formed a bloom in the Murray River since monitoring began in 1978. But crucially, this species flourishes in very warm temperatures; overseas blooms of this species have occurred when water temperatures reach 26℃.

The other difference between the current and earlier blooms is that, when this year’s event started, Lake Hume was much fuller, at about 30% capacity. So reservoir operation probably had less to do with the bloom’s formation than other factors, such as the climate. Both the maximum and minimum temperatures were consistently above the long-term average during the past few months, as was the amount of sunlight reaching the surface of Lake Hume.

We still do not know exactly what triggered this year’s bloom, but if it was indeed a result of unusually warm temperatures, it is very likely that we will see more blooms of this type in the future.

Are we really ready for recurrent blue-green algal blooms on the Murray River? These blooms come at a significant economic cost: drinking water has had to be specially treated to remove potential toxins, and the bloom has impacted on regional tourism, coinciding with the Labour Day and Easter long weekends. It also hit farmers, who had to get drinking water for their livestock from elsewhere.

More importantly, what do these frequent blooms say about how we manage water in this country – especially as we start to see the impacts of climate change on our environment? Dwindling water could mean more than just drought – it could also fill much of the water that remains with poisonous microbes.

Darren Baldwin has received funding from the Murray-Darling Basin Authority to study blue-green algal blooms in the Murray River , including the current bloom.