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Archive for the ‘climate change’ Category

climate change – we know what we should be doing

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Professor Mark Howden of the ANU and the IPCC – straight science and economic sense

Here in Australia we have a national government that hates to mention human-induced climate change publicly, whatever their personal views are, and clearly they’re varied. I’ve long suspected that there’s a top-down policy (which long predates our current PM) of not mentioning anthropogenic global warming, lest it outrage a large part of the conservative base, while doing a few things behind the scenes to support renewables and reduce emissions. It’s a sort of half-hearted, disorganised approach to what is clearly a major problem locally and globally. And meanwhile some less disciplined or less chained members or former members of this government, such as former PM Tony Abbott and current MP for Hughes, Craig Kelly, are ignoring the party line (and science), and so revealing just how half-arsed the government’s way of dealing with the problem really is. The national opposition doesn’t seem much better on this issue, and it might well be a matter of following the money…

So I was impressed with a recent ABC interview with Australian climate scientist and leading member of the IPCC, Professor Mark Howden, also director of the Climate Change Institute at the Australian National University, who spoke a world of good sense in about ten minutes. 

The interview was preceded by the statement that the government is holding to its emission reduction targets – considered to be rather minimal by climate change scientists – while possibly ‘tweaking’ broader climate change policy. This is another example of ‘don’t scare the base’, IMHO. It was also reported that the government felt it might reach its Paris agreement without using ‘carry-over credits’ from the previous Kyoto agreement.  

The issue here is that our government, in its wisdom, felt that it should get credit for ‘more than meeting’ its Kyoto targets. As Howden pointed out, those Kyoto targets were easy to meet because we’d have met them even while increasing our emissions (which we in fact did). Spoken without any sense of irony by the unflappable professor. 

There’s no provision in the Paris agreement for such ‘carry-over credits’ – however the government has previously relied on them as an entitlement, and in fact pushed for them in a recent meeting in Madrid. Now, it’s changing its tune, slightly. The hullabaloo over the bushfire tragedies has been an influence, as well as a growing sense that reaching the Paris targets without these credits is do-able. Interestingly, Howden suggests that the credits are important for us meeting our Paris commitments up to 2030, as they make up more than half the required emissions reductions. So, if they’re included, we’ll need a 16% reduction from here, rather than a 26 – 28% reduction. But is this cheating? Is it in the spirit of the Paris agreement? Surely not, apart from legal considerations. It certainly affects any idea that Australia might play a leadership role in emissions reductions. 

So now the government is indicating that it might scrap the reliance on credits and find real reductions – which is, in fact, a fairly momentous decision for this conservative administration, because the core emissions from energy, transport, waste and other activities are all rising and would need to be turned around (I’m paraphrasing Howden here). So far no policies have been announced, or are clearly in the offing, to effect this turnaround. There’s an Emissions Reductions Fund,  established in 2014-5 to support businesses, farmers, landowners in reducing emissions through a carbon credit scheme (this is news to me) but according to Howden it’s in need of more public funding, and the ‘carbon sinks’ – that’s to say the forests that have been burning horrifically in past weeks  – which the government has been partly relying upon, are proving to be less stable than hoped. So there are limitations to the government’s current policies. Howden argues for a range of additional policies, but as he says, they’ve rejected (presumably permanently) so many options in the past, most notably carbon pricing, that the cupboard looks pretty bare for the future. There’s of course a speedier move towards renewables in electricity generation – which represents about 30% of emissions, the other 70% being with industry, agriculture, transport and mining (see my previous piece on fracking, for example, a practice that looks to be on the increase in Australia). Howden puts forward the case that it’s in this 70% area that policies can be most helpful, both in emissions reduction and jobs growth. For example, in transport, Australia is well behind other nations in the uptake of EVs, which our government has done nothing to support, unlike most advanced economies. Having EVs working off a renewables grid would reduce transport emissions massively. Other efficiencies which could be encouraged by government policy would be reducing livestock methane emissions through feed and husbandry reforms, such as maintaining shade and other stress-reducing conditions. This can increase productivity and reduce per-unit environmental footprint – or hoofprint. 

As to the old carbon pricing argument – Howden points out that during the brief period that carbon pricing was implemented in Australia, core emissions dropped significantly, and the economy continued to grow. It was clearly successful, and its rescinding in around 2015 has proved disastrous. Howden feels that it’s hard to foresee Australia meeting its 2030 Paris targets without some sort of price on carbon – given that there won’t be any deal on carry-over credits. There’s also an expectation that targets will be ramped up, post-2030. 

So, the message is that we need to sensibly revisit carbon pricing as soon as possible, and we need to look positively at abatement policies as encouraging growth and innovation – the cost of doing nothing being much greater than the costs involved in emissions reduction. And there are plenty of innovations out there – you can easily look them up on youtube, starting with the Fully Charged show out of Britain. The complacency of the current Oz government in view of the challenges before us is itself energy-draining – like watching a fat-arsed couch potato yawning his way towards an early death. 

References

https://iview.abc.net.au/show/abc-news-mornings

https://www.environment.gov.au/climate-change/government/emissions-reduction-fund/about

https://ussromantics.com/2020/01/02/fracking-hell/

Written by stewart henderson

January 16, 2020 at 10:37 am

the SUV abomination, or when will we reach peak SUV?

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the anti-SUV – a Tesla Model X, landing in a field somewhere

I was amused by a recent rant from Robert Llewellyn of the highly-recommended Fully Charged vodcasts, regarding the rise and rise of petrol and diesel-fuelled SUV sales in this period of carbon emission concern and climate change. So I have to share an anecdote.

As a young perennially poor person in the seventies I hitch-hiked quite a lot. Hitch-hiking is barely a thing nowadays, and I suspect the hitch-hiking experience I’m about to describe, sometime in the eighties, was my last. It often comes back to annoy me. 

I was picked up by an overweight middle-aged woman with a blaze of dyed blond hair and a dire Aussie accent, in an SUV. Obviously, it was a kind gesture. 

This was my first experience of being in an SUV, and I’ve had very few since. It felt strange to be looking down at other cars on the road. I wondered if this created psychological effects. The woman, I think, tried to elicit conversation but I’m very shy with strangers and pretty hopeless at small talk. So she made her own, which soon developed into a rant against ‘small cars’, which she seemed to regard as death traps and a form of road litter. Certainly there was a strange, disproportionate rage that got to me, as I nodded with an air of non-committal sagacity.

At that point in my life I’d never driven a car – I didn’t get my licence until my late thirties – but I knew the kind of car I wanted to drive, and it was the precise opposite of an SUV, a ridiculous vehicle that was just starting to pollute city streets at the time of this awkward incident. Of course the environment was already a major public issue in the eighties, so I naively thought this woman was on the wrong side of history. The SUV would surely go the way of the dinosaur, in somewhat less than a couple of hundred million years.

But SUV sales are soaring worldwide, in spite of a greater recognition of climate change and anthropogenic global warming due to greenhouse gas emissions. I suppose there’s some excuse for them in Australia, this land of sweeping plains (and sleeping brains), but given our apparent indifference to the EV revolution and the phobia re climate change issues of our federal government, we’re just going to have to put up with these tanks continuing to proliferate in our suburbs. And it’s going on everywhere – there’s currently a huge spike in SUV sales worldwide. I mean, WTF?

So, instead of a pox on SUVs, how about a tax on them? It worked with cigarettes here….

Of course I’m joking. Western governments are more likely to subsidise the manufacture of SUVs than to tax them. This US business website presents in graphic detail the surge in SUV sales:

48% of car sales in the United States last year [2018]’were SUVs, which was the highest percentage worldwide, but other countries are catching up. Large cars can be seen as a status symbol, and sales are rising in countries like China and India where the middle class is growing.

The website cites a study which found that the number of SUVs on the road has increased about six-fold since 2010, and SUVs alone were the second largest contributor to the global increase in carbon emissions during that period. So, I wonder, when will we reach peak SUV?

Written by stewart henderson

January 7, 2020 at 9:05 pm

on dinosaurs and the Cretaceous climate

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sauropods of the Jurassic and Cretaceous – they munched on superfoods, apparently

 

I’ve been reading this entertaining book on dinosaurs by the curmudgeonly controversialist Brian Ford, who insists that dinosaurs were largely aquatic. I know about as much about dinosaurs as Trump knows about government, so I’m not going to wade into the central debate, if there is one (most palaeontologists dismiss Ford’s claim out of hand), but there’s so many items and assertions here worthy of further investigation that I’m bewildered by choice. So I’ve decided that, since there’s so much interest in current climate change and what it might mean for the future of various biosphere life-forms including ourselves, I’ll spend a bit of time researching what’s known about the climate, and the atmosphere, during the Cretaceous period – a very long time-span indeed from a human perspective, stretching from around 145 million years ago to 66 million years ago. It seems to have have been very different then (assuming that 80 million years of weather can be encapsulated in one description) from what it is now, and yet life was thriving – so why worry?

Well, life then was life as we don’t know it now – though, interestingly, many plants of the period still exist today, including plants from even earlier, such as gingkos and horsetails. In fact, the Cretaceous saw the emergence of flowering plants (angiosperms) in great numbers, and this favoured a rise in dinosaur numbers and types. The climate generally was warm, wet and tropical, and according to NASA climate scientists, carbon dioxide levels were at 1000 ppm (in the middle Cretaceous, around 110 mya), compared to around 410 ppm today. Sea levels were around 300 feet higher than today, and surface temperatures averaged 27 degrees celsius compared to about 15 at present. It’s likely that no ice existed anywhere on the planet.

So why so much CO2, and how did it come to drop? To take the second question first, at this time, the continents weren’t where they are today. Some 90 mya India began a rapid movement away from Madagascar towards Asia at a rate of 15-20 cms per year. It collided with the Asian plate some 55-50 mya, creating the Himalayas, and silicate weathering began, resulting in the incorporation of CO2 into carbonate, which washed into the ocean and was buried. The surface temperature started to drop with CO2 levels, which came down to an inter-glacial atmospheric concentration of about 280 ppm in CO2. Once that concentration got down to 450 ppm the Antarctic ice sheet began to form, and the Greenland ice sheet started at around 400pm, all of which is highly relevant to today’s climate situation with its rise in CO2 levels.

As to the first question, plate tectonics and related volcanic emissions appears to provide most of the answers. It’s believed, in fact, that CO2 levels were as high as 4000 ppm during the Cambrian period, over 500 mya (and at their lowest at 180 ppm during the Pleistocene glaciation a little over 2 mya).

None of this, of course, comes close to answering questions about dinosaur lifestyle, but I do note that Brian Ford is an outlier not only for his aquatic dinosaur hypothesis. He also questions, indeed trashes, the dinosaur extinction-by-meteor story, and argues that the sky was probably orange-yellow, to our perception, at the time of the dinosaurs. All of this is contrary to generally accepted science, so he’s rather unlikely to be correct. Having said that, questions about how some of these incredibly massive sauropod beasties managed to get around and consume enough food to maintain themselves – these still appear to be unanswered to a large degree. Hopefully somebody will build a time machine soon.

References

Too big to walk, by Brian Ford, 2018

https://www.livescience.com/44330-jurassic-dinosaur-carbon-dioxide.html

PSW 2404 Satellites, Dinosaurs, Milankovitch Cycles, and Cretaceous Earth | Compton Tucker (video)

What was the climate like during the age of Dinosaurs? / Benjamin Burger (video)

https://ask.metafilter.com/194137/What-color-was-the-sky-millions-or-billions-of-years-ago

https://www.sciencemag.org/news/2019/10/sauropods-grew-big-munching-superfoods-sturdy-beaks

Written by stewart henderson

December 11, 2019 at 12:53 pm

fish deaths in the lower Darling – interim report

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Jacinta: We wrote about this issue in a piece posted on February 11, so it’s time to follow up – an interim report came out on February 20, and a final report is due at the end of March, but my feeling is that the final report won’t differ much from this interim one.

Canto: Yes I get the feeling that these experts have largely known about the situation for a long time – unusual climatic conditions plus an increasing lack of water in the system, which would make the remaining water more susceptible to extremes of weather.

Jacinta: So here’s some of what they’re saying. There were three separate events; the first on December 15 involved tens of thousands of fish deaths over a 30km stretch of the Darling near Menindee, the second on Jan 6-7, over 45kms in the same area, involved hundreds of thousands of deaths, even millions according to some residents, and the third on Jan 28, with thousands of deaths. Likely effects on fish populations in the Darling will last for years.

Canto: And they warn that more deaths are likely to occur – though no major events have been reported since – due to low inflows and continued dry conditions in the catchment area. Monitoring has shown that there are problems of low dissolved oxygen and ‘high stratification’ at various points along the river. I presume ‘high stratification’ is self-explanatory, that the water isn’t mixing due to low flows?

Jacinta: Yes, but I think the issue is thermal stratification, where you have a warm surface layer sitting above a cooler, oxygen-depleted sub-surface layer. These are excellent conditions for algal blooms apparently. And the low flows are a natural feature of the Darling. It’s also very variable in flow, much more so than the Murray, due to its low relief, the more variable rainfall in the region, and the tributaries which create a large catchment area. I don’t know if that makes sense.

Canto: Neither do I. I note that they’ve been carefully critical of the NSW government’s ‘Barwon-Darling Water Sharing Plan 2012’, because between the draft and final implementation of the plan the number of high-flow Class C shares was reduced and the number of Class A (low flow) and Class B (medium flow) shares increased, which meant more extraction of water overall, and at lower flows. They recognise that there have been recent Federal moves to reverse this, but clearly they don’t consider them sufficient.

Jacinta: Yes and the problem goes back a way. They refer to an analysis from almost two decades ago:

The flow regime in the lower Darling has changed significantly since the completion of the Menindee Lakes storage scheme in 1968, and as a result of abstractions in the Barwon–Darling and its tributaries. It is estimated that the mean annual flow in the Darling River has been reduced by more than 40% as a result of abstractions in the Barwon–Darling (Gippel & Blackham, 2002). 

Presumably ‘abstractions’ means what I think it means – though elsewhere they use the term ‘extractions’ which is confusing.

Canto: We should point out the immense complexity of the system we’re dealing with, which we can see from detailed maps that accompany the report, not to mention a number of barely comprehensible charts and graphs. Anyway the effect of ‘water management’ on native vegetation has been dire in some regions. For example, reduced inundation of natural floodplains has affected the health of the river red gums, while other trees have been killed off by the creation of artificial lakes.

Jacinta: And returning to fish deaths, the report states that ‘the influence of upstream extractions on inflows to the Menindee Lakes is an important consideration when assessing the causes of fish deaths downstream’. What they point out is that the proportion of extractions is higher in times of lower inflow, which is intuitively obvious I suppose. And extractions during 2017-8 were proportionally the second highest on record. That’s in the Northern Basin, well above the Menindee Lakes.

Canto: And the extractions have been mainly out of the tributaries above the Barwon-Darling, not those principal rivers. Queenslanders!

Jacinta: No mention of Queenslanders, but let’s not get bogged down..

Canto: Easily done when there’s hardly any water…

Jacinta: Let’s go to the provisional findings and recommendations. There are 18 briefly stated findings in all, and 20 more expansive recommendations. The first two findings are about extreme weather/climatic conditions amplified by climate change, with the expectation that this will be a continuing and growing problem. Findings 3 and 4 focus on the combined effects of drought and development. There’s a lack of updated data to separate out the effects, but it’s estimated that pre-development inflows into the Menindee Lakes were two or three times what they are now. Further findings are that the impact of diversions of or extractions from flows are greater during dry years, that extractions from tributaries are more impactful than extractions from the Barwon-Darling Rivers.

Canto: The findings related directly to fish deaths – principally findings 10 through 15 – are most interesting, so I’ll try to explain. The Menindee Lakes experienced high inflows in 2012 and 2016, which caused greater connection through the river system and better conditions for fish spawning and ‘recruitment’ (I don’t know what that means). So, lots of new, young fish. Then came the bad 2017-8 period, and releases from the Menindee Lakes were less than the minimum recommended under the water sharing plan, ‘with the intent to prolong stock and domestic requests to meet critical human needs’. So by the end of 2018, the high fish biomass became trapped or restricted between weirs, unable to move upstream or downstream. As the water heated up, significant algal blooms developed in the areas where fish had accumulated. Thermal stratification also occurred, with hypoxic (low oxygen) or anoxic (no oxygen) conditions in the lower waters, and algal blooms proliferating in the surface waters, where the fish were forced to hang out. Then conditions suddenly changed, with lower air temperatures and stormy conditions causing a rapid destratification. The low oxygen water – presumably more voluminous than the oxygenated water – dominated the whole water column and the fish had no way out.

Jacinta: Yes, you can’t adapt to such sudden shifts. The final findings are about existing attempts at fish translocation and aerating water which are having some success, about stratification being an ongoing issue, and about lack of knowledge at this preliminary stage of the precise extent of the fish deaths.

Canto: So now to the 20 recommendations. They’re grouped under 3 headings; preventive and restorative measures (1-9), management arrangements (10-13), and knowledge and monitoring (14-20). The report noted a lack of recent systematic risk assessment for low oxygen, stratification and blackwater (semi-stagnant, vegetation-rich water that looks like black tea) in the areas where the fish deaths occurred. There was insufficient or zero monitoring of high-risk areas for stratification, etc, and insufficient planning to treat problems as they arose. Flow management strategies (really involving reduced extraction) need to be better applied to reduce problems in the lower Darling. Reducing barriers to fish movement should be considered, though this is functionally difficult. Apparently there’s a global movement in this direction to improve freshwater fish stocks. Short term measures such as aeration and translocation are also beneficial. Funding should be set aside for research on and implementation of ecosystem recovery – it’s not just the fish that are affected. Long-term resilience requires an understanding of interactions and movement throughout the entire basin. Fish are highly mobile and restriction is a major problem. A whole-of system approach is strongly recommended. This includes a dynamic ‘active event-based management’ approach, especially in the upper reaches and tributaries of the Barwon-Darling, where extraction has been governed by passive, long-term rules. Such reforms are in the pipeline but now need to be fast-tracked. For example, ‘quantifying the volumes of environmental water crossing the border from Queensland to NSW…. would increase transparency and would help the CEWH [Commonwealth Environmental Water Holdings] with their planning, as well as clear the path to move to active management in Queensland’.

Jacinta: Right, you’ve covered most of the issues, so I’ll finish up with monitoring, measuring and reporting. The report argues that reliable, up-to-date accounting of flows, volumes in storage, extractions and losses due to seepage and evaporation are essential to create and maintain public confidence in system management, and this is currently a problem. Of course this requires funding, and apparently the funding levels have dropped substantially over the past decade. The report cites former funding and investment through the Co-operative Research Centre, Land and Water Australia and the National Water Commission, but ‘by the early 2010s, all of these sources of funding had terminated and today aggregate levels of funding have reduced to early 1980s levels, at a time when water was far less of a public policy challenge than it is today’.

Canto: We await the government’s response to that one.

Jacinta: And on fisheries research in particular, it has been largely piecemeal except when their was a concerted co-ordinated effort under the Native Fish Strategy, but the issue right now is to know how many fish (and other organisms) of the various affected species survived the event, which involves multi-level analyses, combined with management of Basin water balances, taking into account the ongoing effects of weather events due to climate change, in order to foster and improve the growth and well-being of fish stocks and freshwater habitats in general. Connectivity of the system in particular is a major concern of the report.

Canto: Right, so this has been a bit of a journey into the unknown for us, but a worthwhile one. It suggests that governments have been a bit dozey at the wheel in recent years, that extractions, especially in the upper reaches and tributaries, haven’t been well monitored or policed, and the connectivity of the system has suffered due to extractions, droughts and climate change. Funding seems to have dried up as much as some of the rivers have, and we’ll have to wait and see if this becomes an election issue. I suspect it’ll only be a minor one.

Written by stewart henderson

March 17, 2019 at 12:01 pm

why are our river fish dying?

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Canto: So here’s a question. Why are so many fish dying in our rivers? I believe it has something to do with oxygen, but that raises a whole heap of questions, like why do fish need oxygen, how does this relate to fish physiology, what’s the difference between freshwater and saltwater fish (is all fish physiology basically the same), and is climate change a factor in all this – or rather, how is it a factor?

Jacinta: Okay so that’s a good focussed question, or set of questions, a bit easier to deal with than the management of our river systems, which would involve inter(and intra)-state politics and the rights or wrongs of irrigators, farmers, industry and the like. I’ve heard all that is rather complicated.

Canto: Right, so we’re just going to focus on the internal and external environment of freshwater fish.

Jacinta: Well, maybe. News reports have claimed up to a million fish deaths in the Darling River, with critically endangered Murray cod being among the victims. Algal blooms ‘which can be caused by agricultural chemicals’ (sky news) are being cited as the proximal cause, but the ultimate cause, according to Menindee Lakes residents, is government mismanagement.

Canto: I would wonder whether there are so many fish in the river to begin with – and that million figure is grossly exaggerated according to various sources. The figure appears to be something between 100,000 and 200,000, still a staggering number, and I wonder about the deaths in proportion to the population, and if some species are dying more than others. We need some science here.

Jacinta: And my preliminary enquiries into the science show that it’s complex and unsettled. The most recent mass death occurred in the Menindee Lakes, south of Broken Hill, a series of lakes connected to the Darling. We know that there was very little flow-through at the time, the water levels were low and water temperature had risen. As a result, there was a large bloom of cyanobacteria, aka blue-green algae. But apparently according to an ABC Science report, the cyanobacteria weren’t exactly the problem, it was their death, caused by a cold front, and the sudden explosion of other bacteria feeding on the dead and dying cyanobacteria, and in the process depleting the water of oxygen, that caused the fish to drown.

Canto: So what we call drowning is really loss of oxygen, which fish have evolved to capture from water but we can’t. How do they do that?

Jacinta: Gills. Fish breathe through their mouths like us. And also like us they need oxygen to function and they breathe out carbon dioxide. Gills – and we could expend pages and pages on their origin, structure and function – are those organs found on each side of the pharynx or throat, and they’re made up of protein structures called filaments. Each filament has a tiny network of blood vessels, providing a large surface area for the exchange of gases. So fish suck in water, with its oxygen, and then pump it out through the gills, where all the essential gas exchange occurs. But if the water isn’t sufficiently oxygenated, then it’s goodnight, sweet fish.

Canto: So the proximal cause isn’t the blue-green algae, it’s the oxygen-consuming bacteria that feed on the algae.

Jacinta: But if the algae weren’t there in the first place, the bacteria that feed on them wouldn’t be there.

Canto: Yes, but that’s only because the algae were dying. What if there hadn’t been this sudden drop in water temperature? Do the algae themselves affect the oxygen levels?

Jacinta: Well, actually, very much so. Cyanobacteria were the first photosynthesising organisms – we wouldn’t be here without them, and they’re now incorporated, in the form of chloroplasts, in all the plants around us. They were the principal means of oxygenating the biosphere.

Canto: So does that mean it’s good to have blue-green algae in our waterways? I’m confused.

Jacinta: The answer is yes and no. The Murray Darling Basin Authority (MDBA), currently under fire from all and sundry, have a useful factsheet about what we’ll henceforth call cyanobacteria. They’re a natural part of the system, and there are a number of species, the two most prominent being Dolichospermum and Microcystis. Under certain optimal conditions for growth, they produce ‘blooms’, which can be toxic at high levels. Mostly though, they don’t affect irrigation, recreational use of the river, or drinking water, if properly treated. It’s the decay of these blooms that causes most problems…

Canto: I note that these fish deaths occurred in the Menindee Lakes, and may have been a result of low water levels, which in turn were due to drought. Lower water levels means a lower volume of water, so that the environmental temperature would more rapidly affect the water temperature than if the volume was greater – no doubt there’s an equation to account for that – which would more quickly affect the decay of the bloom and the growth of the oxygen-depleting bacteria feeding on the bloom. So it seems to me that the ultimate cause is drought, which creates a less stable environment for the fish, and other organisms. How’s that?

Jacinta: Well, it’s the beginning of an explanation, but it’s too simple. It isn’t just drought that’s affecting water levels, it’s the fact that water is drawn from the system. And that involves politics, which we were hoping to steer clear of – oh well. By the way, the fish that have died include Murray cod, golden perch, silver perch, and bony herring. I don’t have relative numbers though. The Menindee Lakes region, which is at the centre, not only of this fish death controversy, but of the entire Murray-Darwin Basin management controversy, appears to be at crisis point, and the locals aren’t happy. Here are some quotes from The Guardian on the issue:

Since the 1960s, the original Menindee Lakes have been significantly altered to serve as a major storage for water for the Murray-Darling Basin as well as the water supply for Broken Hill. The lakes are also a major fish breeding area for native fish, and critical to maintaining stocks of fish throughout the river system.

However, the NSW government has proposed shrinking the lakes and altering the way it manages the water storage, in order to reduce evaporation. It is currently building a $500m pipeline from the Murray to Broken Hill in order to provide the inland city with an alternative water supply.
But the plan is highly controversial because it will mean the government has less reason to keep the lakes full and will likely see the Lower Darling run dry more often.
Local graziers and the towns of Wilcannia and Pooncarie are up in arms about the state of the river, accusing the NSW government of sacrificing their 500km stretch of the Darling in order to benefit upstream cotton growers.
They say the current crisis is due to Water NSW’s decision to run the lakes dry despite forecasts of drought.

Canto: The MDBA, which is a federal body, presents their reasons for the fish deaths in two concise points:

  • the lack of water flowing into the northern rivers
  • the impact of 100 years of over-allocation of precious water resources throughout the entire Basin.

Drought and the removal of water from the system, precisely your point, Jacinta. The MDBA of course avoids blame, and says nothing about possible current over-allocation. It does, however, say, in the same information page, that ‘the Menindee Lakes are currently under the sole control of New South Wales and have been carefully managed since December 2017’, which appears to court some controversy.

Jacinta: And finally, something important to watch out for as we seek an ultimate answer to our question. An independent panel of six science worthies has been appointed by the Federal government to enquire into these deaths. Fields of expertise include catchment hydrology, fluvial geomorphology, freshwater ecology, plant ecotoxicology, aquatic ecosystem health and much much more. The team will provide a preliminary report to the Feds by February 20, and a final report should be completed by March 31. We’ll look out for it – presumably it will be released to the public.

Written by stewart henderson

February 11, 2019 at 12:28 am

more about ozone, and the earth’s greatest extinction event

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the Siberian Traps are layers of flood basalt covering an area of 2 million square kilometres

Ozone, or trioxygen (O3), an unstable molecule which is regularly produced and destroyed by the action of sunlight on O2, is a vital feature in our atmosphere. It protects life on earth from the harmful effects of too much UV radiation, which can contribute to skin cancers in humans, and genetic abnormalities in plant life. In a previous post I wrote about the discovery of the ozone shield, and the hole above Antarctica, which we seem to be reducing – a credit to human global co-operation. In this post I’m going to try and get my head around whether or not ozone depletion played a role in the so-called end-Permian extinction of some 250 mya. 

I first read of this theory in David Beerling’s 2009 book The emerald planet, but recent research appears to have backed up Beerling’s scientific speculations – though speculation is too weak a word. Beerling is a world-renowned geobiologist and expert on historical global climate change. He’s also a historian of science, and in ‘An ancient ozone catastrophe?’, chapter 4 of The emerald planet, he describes the discovery and understanding of ozone through the research of Robert Strutt, Christian Schönbein, Marie Alfred Cornu, Walter Hartley, George Dobson, Sidney Chapman and Paul Crutzen, among others. He goes on to describe the ozone hole discovery in the 70s and 80s, before focusing on research into the possible effects of previous events – the Tunguska asteroid strike of 1908, the Mount Pinatubo eruption of 1991 and others – on atmospheric ozone levels, and then homes in on the greatest extinction event in the history of our planet – the end-Permian mass extinction, ‘the Great Dying’, which wiped out some 95% of all species then existing.

According to Beerling, it was an international team of palaeontologists led by Henk Visscher at the University of Utrecht who first made the claim that stratospheric ozone had substantially reduced in the end-Permian. They hypothesised that, due to the greatest volcanic eruptions in Earth history, which created the Siberian Traps (layers of solidified basalt covering a huge area of northern Russia), huge deposits of coal and salt, the largest on Earth, were disrupted:


The widespread heating of these sediments and the action of hot groundwater dissolving the ancient salts, was a subterranean pressure cooker synthesising a class of halogenated compounds called organohalogens, reactive chemicals that can participate in ozone destruction. And in less than half a million years, this chemical reactor is envisaged to have synthesised and churned out sufficiently large amounts of organohalogens to damage the ozone layer worldwide to create an intense increased flux of UV radiation.

However, Beerling questions this hypothesis and considers that it may have been the eruptions themselves, which lasted 2 million years and occurred at the Permian-Triassic boundary 250-252 mya, rather than their impact on salt deposits, that did the damage. There’s evidence that many of the eruptions originated from as deep as 10 kilometres below the surface, injected explosively enough to reach the stratosphere, and that these plumes contained substantial amounts of chlorine. 

More recent research, published this year, has further substantiated Visscher’s team’s finding regarding genetic mutations in ancient conifers and lycopsids, and their probable connection with UV radiation enabled by ozone destruction. The mutations were global and dated to the same period. Laboratory experiments exposing related modern plants to bursts of UV radiation have produced more or less identical spore mutations.

The exact chain of events linking the eruptions to the ozone destruction have yet to be worked out, and naturally there’s a lot of scientific argy-bargy going on, but the whole story, even considering that it occurred so far in the past is a reminder of the fragility of that part of our planet that most concerns us – the biosphere. The eruptions clearly altered atmospheric chemistry and temperature. Isotopic measurements of oxygen in sea water suggest that equatorial waters reached more than 40°C. As can be imagined, this had killer effects on multiple species. 

So, we’re continuing to gain knowledge on the ozone shield and its importance, and fragility. I don’t know that there are too many ozone hole skeptics around (I don’t want to look too hard), but if we could only get the same kind of apparent near-unanimity with regard to anthropogenic global warming, that would be great progress. 

Written by stewart henderson

October 10, 2018 at 3:15 pm

the battle for and against electric vehicles in Australia, among other things

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Toyota Camry hybrid – hybrids are way outselling pure EVs here, probably due to range anxiety and lack of infrastructure and other support

I’ve probably not been paying sufficient attention, but I’ve just learned that the Federal Energy minister, Josh Frydenberg, is advocating, against the naysayers, for government support to the EV industry. An article today (Jan 22) in The Australian has Frydenberg waxing lyrical about the future of EVs, as possibly being to the transport sector ‘what the iPhone has been to the communication sector’. It’s a battle the future-believers will obviously win. A spokesman for the naysayers, federal Liberal Party MP and AGW-denier Craig Kelly, was just on the gogglebox, mocking the idea of an EV plant in Elizabeth here in South Australia (the town I grew up in), sited in the recently abandoned GM Holden plant. His brilliantly incisive view was that since Holdens failed, a future EV plant was sure to fail too. In other words, Australians weren’t up to making cars, improving their practice, learning from international developments and so forth. Not exactly an Elon Musk attitude.

The electric vehicles for Elizabeth idea is being mooted by the British billionaire Sanjeev Gupta, the ‘man of steel’ with big ideas for Whyalla’s steelworks. Gupta has apparently become something of a specialist in corporates rescues, and he has plans for one of the biggest renewables plants in Australia – solar and storage – at Whyalla. His electric vehicle plans are obviously very preliminary at this stage.

Critics are arguing that EVs are no greener than conventional vehicles. Clearly their arguments are based on the dirty coal that currently produces most of the electricity in the Eastern states. Of course this is a problem, but of course there is a solution, which is gradually being implemented. Kiata wind farm in Western Victoria is one of many small-to medium-scale projects popping up in the Eastern states. Victoria’s Minister for Energy, Environment and Climate Change (an impressive mouthful) Lily D’Ambrosio says ‘we’re making Victoria the national leader in renewable energy’. Them’s fightin words to we South Aussies, but we’re not too worried, we’re way ahead at the moment. So clearly the EV revolution is going hand in hand with the renewable energy movement, and this will no doubt be reflected in infrastructure for charging EVs, sometimes assisted by governments, sometimes in spite of them.

Meanwhile, on the global scale, corporations are slowly shuffling onto the renewables bandwagon. Renew Economy has posted a press release from Bloomberg New Energy Finance, which shows that corporations signed a record volume of power purchase agreements (PPAs) for clean energy in 2017, with the USA shuffling fastest, in spite of, or more likely because of, Trump’s dumbfuckery. The cost-competitiveness of renewables is one of the principal reasons for the uptick, and it looks like 2018 will be another mini-boom year, in spite of obstacles such as reducing or disappearing subsidies, and import tariffs for solar PVs. Anyway, the press release is well worth a read, as it provides a neat sketch of where things are heading in the complex global renewables market.

Getting back to Australia and its sluggish EV market, the naysayers are touting a finding in the Green Vehicle Guide, a federal government website, which suggested that a Tesla powered by a coal-intensive grid emitted more greenhouse gas than a Toyota Corolla. All this is described in a recent SMH article, together with a 2016 report, commissioned by the government, which claimed that cars driven in the Eastern states have a “higher CO2 output than those emitted from the tailpipes of comparative petrol cars”. However, government spokespeople are now admitting that the grid’s emission intensity will continue to fall into the future, and that battery efficiency and EV performance are continuously improving – as is obvious. Still, there’s no sign of subsidies for EVs from this government, or of future penalties for diesel and petrol guzzlers. Meanwhile, the monstrous SUV has become the vehicle of choice for most Australians.

While there are many many honourable exceptions, and so many exciting clean green projects up and running or waiting in the wings, the bulk of Australians aren’t getting the urgency of climate change. CO2 levels are the highest they’ve been in 15 million years (or 3 million, depending on website), and the last two years’ published recordings at Mauna Loa (2015 and 2016) showed increases in atmospheric CO2 of 3PPM for each year, for the first time since recording began in 1960 (when it was under 1PPM). This rate of CO2 growth, apparently increasing – though with variations due largely to ENSO – is phenomenal. There’s always going to be a see-saw in the data, but it’s an ever-rising see-saw. The overall levels of atmospheric CO2 are now well above 400PPM. Climate Central describes these levels as ‘permanent’, as if humans and their effects will be around forever – how short-sighted we all are.

The relationship between atmospheric CO2 and global warming is fiendishly complex, and I’ll try, with no doubt limited success, to tackle it in future posts.

 

Mustn’t forget my update on Trump’s downfall: the Mueller team has very recently interviewed A-G Sessions, who’s been less than honest about his meetings with Russians. Nobody knows what Sessions was asked about in in his lengthy session (haha) with the inquirers, but he’s a key figure when it comes to obstruction of justice as well as conspiracy. Word now is that Trump himself will be questioned within weeks, which could be either the beginning of the end, or just the end. Dare to hope.

 

Written by stewart henderson

January 26, 2018 at 10:26 am