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Tesla to roll out “multiple” Powerpacks in NSW battery storage win
Clean coal won’t cut it, on costs or emissions, says Climate Council
Boom in rooftop PV shifting peaks, and taking market operator by surprise
Leading regional technical and advisory firm launches new brand, Ekistica
Invitation to comment on listing assessment for Assemblage of species associated with open-coast salt-wedge estuaries of western and central Victoria
Chinese scientists use satellite to smash quantum entanglement record
Carnegie gets nod for 10MW solar farm: “We should have lots of these””
Finkel’s Clean Energy target little more than state’s business-as-usual
Volcanoes under the ice: melting Antarctic ice could fight climate change
Iron is not commonly famous for its role as a micronutrient for tiny organisms dwelling in the cold waters of polar oceans. But iron feeds plankton, which in turn hold carbon dioxide in their bodies. When they die, the creatures sink to the bottom of the sea, safely storing that carbon.
How exactly the iron gets to the Southern Ocean is hotly debated, but we do know that during the last ice age huge amounts of carbon were stored at the bottom of the Southern Ocean. Understanding how carbon comes to be stored in the depth of the oceans could help abate CO2 in the atmosphere, and Antarctica has a powerful role.
Icebergs and atmospheric dust are believed to have been the major sources of this micronutrient in the past. However, in research published in Nature Communications, my colleagues and I examined calcite crusts from Antarctica, and found that volcanoes under its glaciers were vital in delivering iron to the ocean during the last ice age.
Today, glacial meltwaters from Greenland and the Antarctic peninsula supply iron both in solution and as tiny particles (less than 0.0001mm in diameter), which are readily consumed by plankton. Where glaciers meet bedrock, minute organisms can live in pockets of relatively warm water. They are able to extract “food” from the rock, and in doing so release iron, which then can be carried by underwater rivers to the sea.
Volcanic eruptions under the ice can create underwater subglacial lakes, which, at times, discharge downstream large masses of water that travel to the ice margin and beyond, carrying with them iron in particle and in solution.
The role of melting ice in climate change is as yet poorly understood. It’s particularly pertinent as scientists predict the imminent collapse of part of the Larsen C ice shelf.
Researchers are also investigating how to reproduce natural iron fertilisation in the Southern Ocean and induce algal blooms. By interrogating the volcanic archive, we learn more about the effect that iron fertilisation from meltwater has on global temperatures.
A polished wafer of the subglacial calcites. The translucent, crystalline layers formed while in pockets of water, providing nourishment to microbes. The opaque calcite with rock fragments documents a period when waters discharged from a subglacial lake formed by a volcanic eruption, carrying away both iron in solution and particles of iron. Supplied The Last Glacial MaximumDuring the Last Glacial Maximum, a period 27,000 to 17,000 years ago when glaciers were at their greatest extent worldwide, the amount of CO2 in the atmosphere was lowered to 180 parts per million (ppm) relative to pre-industrial levels (280 ppm).
Today we are at 400 ppm and, if current warming trends continue, a point of no return will be reached. The global temperature system will return to the age of the dinosaurs, when there was little difference in temperature from the equator to the tropics.
If we are interested in providing a habitable planet for our descendants, we need to mitigate the quantity of carbon in the atmosphere. Blooms of plankton in the Southern Ocean boosted by iron fertilisation were one important ingredient in lowering CO2 in the Last Glacial Maximum, and they could help us today.
The Last Glacial Maximum had winds that spread dust from deserts and icebergs carrying small particles into the Southern Ocean, providing the necessary iron for algal blooms. These extreme conditions don’t exist today.
Hidden volcanoesNeither dust nor icebergs alone, however, explain bursts of productivity recorded in ocean sediments in the Last Glacial Maximum. There was another ingredient, only discovered in rare archives of subglacial processes that could be precisely dated to the Last Glacial Maximum.
Loss of ice in Antartica’s Dry Valleys uncovered rusty-red crusts of calcite plastered on glacially polished rocks. The calcites have tiny layers that can be precisely dated by radiometric techniques.
A piece of subglacial calcite coating pebbles. This suggests that the current transporting the pebbles was quite fast, like a mountain stream. The pebbles were deposited at the same time as the opaque layer in the calcite formed. SuppliedEach layer preserves in its chemistry and DNA a record of processes that contributed to delivering iron to the Southern Ocean. For example, fluorine-rich spherules indicate that underwater vents created by volcanic activity injected a rich mixture of minerals into the subglacial environment. This was confirmed by DNA data, revealing a thriving community of thermophiles – microorganisms that live in very hot water only.
Then, it became plausible to hypothesise that volcanic eruptions occurred subglacially and formed a subglacial lake, whose waters ran into an interconnected system of channels, ultimately reaching the ice margin. Meltwater drained iron from pockets created where ice met bedrock, which then reached the ocean – thus inducing algal blooms.
We dated this drainage activity to a period when dust flux does not match ocean productivity. Thus, our study indicates that volcanoes in Antarctica had a role in delivering iron to the Southern Ocean, and potentially contributed to lowering CO2 levels in the atmosphere.
Our research helps explain how volcanoes act on climate change. But it also uncovers more about iron fertilisation as a possible way to mitigate global warming.
Silvia Frisia receives funding from ARC.
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How should world leaders punish Trump for pulling out of Paris accord? | Wael Hmaidan
The international community must show Trump, and any other leaders that may follow suit, that other core diplomatic goals – such as Nato funding – will depend on honouring their climate commitments
World leaders’ response to Donald Trump’s announcement that he would withdraw the US from the Paris agreement was strong and unified. But did it sting the president and his administration? To deter other potential backsliders and maintain the integrity of the Paris agreement, the perpetrator of a defection of this magnitude should be made to feel the pain. But how?
Continue reading...Air pollution plan 'unfair' on local authorities
Ratty returns: hundreds of water voles released in UK's biggest reintroduction
Almost 700 of the endangered rodents, immortalised in Wind in the Willows, will be released in Northumberland – and it’s all thanks really to the otter
The biggest reintroduction of water voles in the UK began this week, with 325 voles released into Kielder Forest in Northumberland, and 350 more to follow later in the summer.
Water voles hold a special place in Britain’s natural history, providing the model for Ratty, the much-loved character in The Wind in the Willows. But the species has suffered catastrophic declines over several decades, driven by loss of habitat, the pollution of waterways, increased urbanisation, and rampant populations of American mink, originally farmed for their fur but which escaped into the wild and proved a voracious predator on the native vole.
Continue reading...How South Australians dumped a nuclear dump
Australians invested in US anti-Paris lobbying
Australian Energy Storage 2017 conference – the low key buzz
Bernardi goes solar to “keep the lights on,” but did he get storage?
Lily beetle wears a frock of frass to deter foes
Crook, Country Durham Tiny larvae hatched then covered their bloated bodies in their own sticky excrement so they resembled bird droppings
At first I thought the flash of red under the leaf was a ladybird. Then I realised that this was a scarlet lily beetle, which has the delightfully alliterative scientific name of Lilioceris lilii.
These gaudy insects have a formidable appetite for lily foliage and have spread from their native Eurasia throughout most of the temperate northern hemisphere. They first appeared in a Surrey garden in 1939 and reached the US in 1943. They turned up in my garden in May.
Continue reading...Politics podcast: Josh Frydenberg, George Christensen and Mark Butler on the Finkel review
Malcolm Turnbull declared on Wednesday he’d “provided decisive leadership on energy”. It is a claim perhaps better cast in the future tense.
The debate over the Finkel panel’s recommendation for a clean energy target (CET) is just beginning, and already it is clear that reaching an outcome that brings the certainty the business community needs to invest will be a hard slog for Turnbull, who will be undermined by critics on his own side.
In this podcast we talk Finkel with Energy Minister Josh Frydenberg, Nationals backbencher George Christensen, and opposition climate spokesman Mark Butler.
Frydenberg, charged with the detailed heavy-lifting, tells Michelle Grattan: “We have to work together as a team to land this difficult policy area.”
Christensen proudly wears the agrarian socialist title as he advocates for radical changes to the regulation of Australian energy prices. “Being bold is the answer and market intervention has to happen.” He’s sceptical of a CET without seeing the modelling and data.
Butler believes a CET is workable but it has to be consistent with principles, which means such a scheme shouldn’t incorporate so-called “clean” coal. “The discussion of the Finkel report shouldn’t include concessions for the hard-right-wing,” he says.
Michelle Grattan does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.