Archive for the ‘climate change’ Category
a shallow dive into economics, and the discovery of a (possible) heroine
Shemara Wikramanayake, speaking at the G20 International Conference on Climate
Don’t know much about economics, to put it mildly, being constitutionally work-shy and generally impoverished in a rich country, so it seems absurd for me to occasionally buy and try to make sense of Britain’s internationally focussed mag, The Economist. To be fair to myself, it does have many interesting articles on international politics, reminding me that the bizarreries of the USA and our domestic difficulties re housing and mortgages (in Australia) are far from the most-life threatening issues on the planet. But when it comes to bond markets, IPOs, floaters, monetary policy and the like, I defer to the cognoscenti while suffering a touch of FOMO.
So, with all that, I’m going to present here an almost incomprehensible (to me) letter to the editor from the August 26 2023 issue, entitled ‘Do we need banks?’
I’m not sure what part of David Apgar’s piece on narrow banking was the most entertaining (‘By Invitation’, August 12). The idea that the ‘Chicago Plan’ was conceived with ‘the Depression fresh in mind’ must be viewed as quite original. However, almost equally amusing was Mr Apgar’s suggestion that bank lending ‘fuels credit to enterprising businesses’, when he realises that the problem with Silicon Valley Bank was that it had invested an awful lot of money in notes issued by the Federal Reserve, supposedly also to fuel commerce (and thus revealing the mockery underlying quantitative easing).
None of this has anything to do with supporting ‘enterprising businesses’ that increase prosperity. Banking is doing something else. Banks should go out and make money from the people who deposit money, assuming that they will keep it safe. Instead they are admonished to multiply paying services offered to those who trust them, and still go bankrupt. Do we need the banks or do the banks need us? And if the latter, then why do we need the banks?
I can’t really make sense of much of this, but the writer’s final ‘killer punch’ is surely ridiculous. We needed and used banks in the past because it was unsafe to keep our money ‘under the bed’ or stuffed in oversized wallets. Nowadays WEIRD society is pretty well cashless and we pay with cards or phones electronically connected to our bank accounts. How would we manage without this? And banks need us to pay for their staff, their buildings etc. Think mutual providence(?).
Of course, as someone who has never taken out a loan in my life, I was clueless about how banks make profits. And the fact is, some banks make eye-watering profits. The CEO of the ‘Macquarie Group’ (whatever that means, but I presume it includes the Macquarie Bank which I think is an investment bank, meaning it has nothing to do with me), one Shemara Wikramanayake, earned just under $24 million in the 2022 financial year, presumably due to the profitability of the ‘Group’ she heads. This is an obscene amount of money, and I find it hard to believe she lives on the same planet as myself. Her Wikipedia profile presents her and her ‘Group’ as a heavy hitter in the financing of low carbon emissions technologies, which is great, but I just don’t understand such super-massive wealth disparities…
Having said all that, my hope in starting this piece was to try and understand the concept of quantitative easing, without the apparent cynicism of the letter quoted above (its author tells us that banking ‘is doing something else’ other than supporting enterprising businesses, inferring of course that ‘banking’ is out to make money for itself, which of course is necessarily true, otherwise it wouldn’t have the funds to continue supporting other enterprising businesses). Here’s how Forbes puts it:
Quantitative easing—QE for short—is a monetary policy strategy used by central banks like the Federal Reserve. With QE, a central bank purchases securities in an attempt to reduce interest rates, increase the supply of money and drive more lending to consumers and businesses. The goal is to stimulate economic activity during a financial crisis and keep credit flowing.
Which leads me to further questions – what’s a ‘central bank’, what are ‘securities’, and what is monetary policy’? I’m sure I’ve heard somewhen that it’s the opposite of fiscal policy but that don’t help much.
I’m guessing that the ‘Federal Reserve’ is the USA’s equivalent of our RBA (the Reserve Bank of Australia):
‘We conduct monetary policy, determine payments system policy, work to maintain a stable financial system, issue the nation’s banknotes, operate the core of the payments system and provide banking services to the government’.
Looks like it’ll take me a while to get to QE, but safly safly catchee monkey. Here’s the RBA again:
In Australia, monetary policy involves influencing interest rates to affect aggregate demand, employment and inflation in the economy. It is one of the main economic policies used to stabilise business cycles.
Of course, I’ve heard of the RBA raising/lowering interest rates, and this affects both savings and loans, obviously. But why does this have to be fixed nationally, why can’t banks fix their own rates and let the customer decide which bank to go with? And is it necessary for private banks to follow the RBA’s decisions? (From what I’ve gleaned they don’t have to but generally keep close to the RBA’s settings). And how do interest rates affect ‘aggregate demand’ (defined as ‘the total demand for goods and services within a particular market’)? Does anybody really understand all this – apart from the magnificently named Shemara Wikramanayake?
I must admit to having only a modicum of interest (careful with that word) in the minutiae of economics, but at least my teeny research has brought to mind Ms Wikramanayake as a rare female in the world of financial movers and shakers. She’s Australia’s highest paid CEO due to the profitability of the Group she heads. Obviously I can’t speak to the economics of that, or any attached ethical issues relating to such massive profits, but these profits appear to be related largely to industries and start-ups in the field of renewable, clean energy. In a world of too many macho anti-feminist thugs like Putin, Xi and those who govern Iran, Burma and too many other countries, we need more positive, future-facing, can-do types like her.
I might actually return to trying to understand QE, corporate bonds and the like, in later posts, but maybe not.
References
The Economist, 26/8 – 1/9/2023
global warming worries
Gaia Vince strikes me as a positive type, as opposed to an optimist. An optimist, as I see it, is someone who just feels that the future will be better than the past – that ‘something will turn up’ – while a positivist (not of the logical type) explores and promotes solutions, generally with the requisite realism – nary a solution that doesn’t entail its own problems.
Nomad Century is a remarkable book, which tries to pack as many possible solutions to the global warming situation as possible in a couple of hundred pages, while recognising that the situation is already serious enough to warrant collaborative international action to support the most vulnerable, who are also largely the most innocent in terms of creating the crisis. In this post I’ll try to summarise these ideas and solutions, principally for my own referential purposes.
- Migration
Our history is all about migration. I’m a migrant. Nations, borders, passports and visas are ultra-modern phenomena. Migration has brought helpful genetic input to receiving populations. Clearly we will not bring global warming to less than 1.5c before 2050, probably not even close. We have a responsibility to help those who will increasingly suffer from drought, flooding and fire in coming decades. And while migration is generally a benefit to all, in spite of xenophobic attitudes, planned migration will be much more successful. The United Nations, and other international organisations that have some heft in the world, need to step up as the situation worsens. We need to recall that global society is entirely reliant on movement – of goods. Australia was once a hub of manufacturing. I know, it provided me with employment for much of my youth. Now those goods, including motor vehicles, are pretty much entirely imported, while we rely on exports, mostly of iron ore, coal and gas, to China, Japan and other Asian countries. International trade has expanded muchly in recent decades, creating levels of interdependence never before seen, and yet we tend to be obsessed with guarding our borders. To quote Vince:
As humanity faces its greatest environmental challenge – a population of 10 billion people, resource limitations, and a demographic crisis – we should not be handicapping ourselves by limiting our most important survival tool. We will only meet our global challenges through planned and extensive human movement and redistribution…. we need lawful, safe, planned and facilitated migration.
2. Population
I recall as a kid reading, probably in an out-of-date textbook, that our human population was around 3 billion. In fact we got to one billion early in the 19th century, after some 300,000 years of existence. The World Population Clock now has it at a little over 8 billion, and it will certainly be over 9 billion by mid-century. However, in most WEIRD nations the growth is slow or negative, while nations such as Niger and South Sudan have much higher birth rates. This raises issues around ageing populations, which could be balanced by immigration.
In 2008 the world population became officially more urban than rural, and internal migration to cities continues apace. Cities and their governance and future planning are thus becoming an increasingly vital factor in climate change mitigation. With effective collaboration within and between urban centres, solutions to urban problems re pollution and carbon emissions can be multiplied and shared. The greening of cities is often seen as a benefit in itself, which citizens of differing ideologies can get behind. Environmentalist writer Ihni Jon quotes city planners in Darwin:
We’re trying to create a more pleasant environment in the city for people to roam around and hang out more, which could help the economy of our city. ‘Creating a pleasant condition’, or ‘creating a destination’, has become the motivator for planners to be engaged more with nature and the environment in general.
Then again, the question needs to be asked – how bearable will the environment be in a city like Darwin in the second half of this century? Today is the first official day of spring in Australia, and it has just been announced that the winter just completed was the warmest since records have been kept. And so it goes.
3. Decarbonisation
Everybody is talking about this, but fossil fuel emissions continue to increase. As Vaclav Smil tells us clearly in How the world really works, we’re far from finding ‘replacement’ energy for air travel, shipping and agriculture. Our agriculture industry has been revolutionised since the early 1900s by the mass-production of ammonia (NH3), As the Climate Portal puts it:
…ammonia has to be made at a high pressure under high temperatures—meaning it takes a lot of energy to manufacture. Most of that energy comes from burning fossil fuels like coal and methane gas, which give off the greenhouse gas carbon dioxide, the main cause of climate change.
CO2 emissions from ammonia production make up between 1% and 2% of the whole. Emissions from agriculture in general make up around 12%, while a little over 14% comes from transportation. Arguably the sector that can most ‘easily’ be transformed is the ‘general energy’ sector – households and businesses using fossil fuel-based electricity, and gas, for heating, cooling and multitudinous appliances. But we’re a long way from making inroads even in this sector, and we’ve only just managed, more or less, to convince the general population that global warming is a real thing with serious consequences for the biosphere.
With the human population very much on the rise, and the ongoing quest to raise living standards for all, the pressure is on to find solutions. Nuclear fission is an option, and it’s disappointing to note the degree of misinformation around this technology. Australia would be a better location than most, but there seems little public appetite here, perhaps because our climate and open spaces are so well suited to solar. Much has been reported about small modular reactors (SMRs):
The term SMR refers to the size, capacity and modular construction only, not to the reactor type and the nuclear process which is applied. Designs range from scaled down versions of existing designs to generation IV designs. Both thermal-neutron reactors and fast-neutron reactors have been proposed, along with molten salt and gas cooled reactor models.
Again, the appetite just doesn’t seem to be there, and nuclear fusion, which I’ve recently written about, looks to be far into the future still.
Lifestyle change, in terms of what we eat, how we build or refit our homes, and how we recycle our waste, will help, but not enough. A sense of urgency is rising among the cognoscenti, but with the world so divided in other areas (Russia, China, Iran, the USA, etc), it may take a real kick up the biospheric arse (a devastating El Niño?) to wake us up to truly collective action. Meanwhile, we may need to loosen our cherished borders a bit to help those already affected by global warming.
There are some interesting techno-solutions I’ve half-learned about through reading Nomad Century, and I’ll try to learn more about them via a future post.
References
Gaia Vince, Nomad century, 2022
Ihni Jon, Cities in the Anthropocene, 2021
https://climate.mit.edu/explainers/fertilizer-and-climate-change
Vaclav Smil, How the world really works, 2022
Amazing internet, female science communicators and fighting global warming: an interminable conversation 4
from Renew Economy – SA doing quite well
Jacinta: As I’ve said many times – or at least I’ve thought many times – the internet is surely the greatest development in human history for those interested in self-education. Can you think of anything to compare?
Canto: Not really. The printing press was important, but literacy rates were much lower when that came out – which makes me think that universal education, which includes literacy of course, must be up there. But of course it was never really universal, and I suppose neither is the internet, but it appears to have penetrated further and wider, and much faster than any previous technology…
Jacinta: Universal education was more or less compulsory, and so very top-down. Not self-education at all. The internet gives every individual more control…
Canto: And most choose to stay within their own social media bubble. But for those keen to learn, yes the internet just gets more and more fantastic.
Jacinta: And the trend now is for spoken presentations, with bells and whistles, rather than reams of writing, which can be off-putting…
Canto: Well, our stuff is pretend-speak. We don’t do videos because we’re both extremely ugly, and even our voices are hideous, and we haven’t a clue about bells and whistles.
Jacinta: Sigh. Consigned to obscurity, but we must perforce mumble on into the vacuum of our little internet space. Even so, I’d like to enthuse, however impotently, about the many excellent female science presenters out there, with their vodcasts or vlogs or whatever, such as Australia’s Engineering with Rosie, as well as Kathy loves physics and history, Sabine Hossenfelder and Dr Becky. And I’ll keep an eye out for more.
Canto: But of course we still love books. The most recent read has been Saul Griffith’s The Big Switch, a call to action on renewables, particularly here in Australia.
Jacinta: So with a change of government, Australia is now going to try and catch up with the leading nations re renewable energy and generally changing the energy landscape. So it’s time to turn to the Renew Economy website, the best Australian site for what’s happening with renewables. First stop is the bar graph that’s long featured on the site. It shows that the eastern states, Queensland, NSW and Victoria, are the problem states, still heavily reliant on coal. Victoria is arguably worst as it relies on brown coal for about two thirds of its supply.
Canto: And the other two states use black coal, but they’ve developed a lot more solar than Victoria. They are, of course, a lot sunnier than Victoria. What’s the difference between the two coals, in environmental terms?
Jacinta: Black coal, aka anthracite, is generally regarded as a superior fuel. It contains less water than brown coal, aka lignite, and more carbon. You have to use quite a lot more brown coal – maybe 3 times as much – to extract the same amount of energy as anthracite. According to Environment Victoria,
Brown coal is pulverised and then burned in large-scale boilers. The heat is used to boil water and the steam is used to drive turbines that generate electricity. When brown coal is burnt it releases a long list of poisonous heavy metals and toxic chemicals like sulphur dioxide, mercury, particulate matter and nitrogen oxides. By world standards these pollutants are poorly monitored & controlled, and they impose a staggering health cost of up to $800 million every year.
I’ve left in the links, which are to other Environment Victoria articles. Clearly this website isn’t government controlled, as it castigates heavily subsidised ‘boondoggle’ projects intended to keep the brown coal afloat (very problematic for mining). These projects have apparently gone nowhere. However the site does mention the ‘recent’ announcement of an electric vehicle manufacturing plant in the Latrobe Valley, providing at least 500 jobs. But since the article isn’t dated, I don’t know how recent it is. PLEASE DATE YOUR ARTICLES.
Canto: Yeah, and please do your research Jazz. That plant, announced in 2018, was scrapped last November. Apparently it was announced ahead of the 2018 election. And over-hyped, as it was never guaranteed that the ‘promised’ 500 jobs would be created. Politics.
Jacinta: Sad. Manufacturing has been in a sorry state in Australia for years. As Saul Griffith points out, we rely largely on the raw materials – crushed rocks – we export to keep our economy going, but if we could switch to other crushed rocks for the growing renewable energy economy we would be even better off. Further, if we added value through processing this material at home, we might be even better off financially, and we wouldn’t have to import those processed materials as we do now. Our two biggest imports are petrol and cars. If we could produce that stuff here we wouldn’t be paying for another country’s production costs, according to Griffith. Though I’m not quite sure if it’s that simple.
Canto: So you’re talking essentially about manufacturing in Australia. The Reserve Bank (RBA) has an interesting article on this topic, and here’s a quote from the opening summary:
Manufacturing output and employment have fallen steadily as a share of the Australian economy for the past three decades… the increase in the supply of manufactured goods from low-cost sources abroad, exacerbated by the appreciation of the Australian dollar during the period of rising commodity prices, impaired the viability of many domestic manufacturers and precipitated the closure of some manufacturing production over the past decade. While the recent exchange rate depreciation has helped to improve competitiveness of Australian producers, so far there is only limited evidence of a recovery in manufacturing output and investment.
Economics isn’t my strong suit, but I think I understand what ‘exchange rate depreciation’ means. Something like the exchange rate has swung a bit more in our favour (for home-grown manufacturing) than it was before..
Jacinta: But wouldn’t the exchange rate between us and other countries vary greatly from country to country? Or maybe they take an average, that’s to say of the countries we tend to trade with?
Canto: I suppose so. The article goes on to say that manufacturing hasn’t declined so much as commodity exports have increased. Commodities being raw materials, mostly. And by the way, this article is from the June quarter of 2016, and I suspect things have gotten worse for this gap between manufacturing and commodities. So, not so out-of date re trends. It claims that ‘over the 2000s, strong Asian demand for Australian commodities led to a sharp increase in the terms of trade and an appreciation of the Australian dollar’.
Jacinta: Well, we all appreciate the Aussie dollar…
Canto: Appreciation just means a rise in value. An increase in the terms of trade means an increase in the trading price agreed by any two countries, for example Australia and China, our big bogey man trading partner. Here it might mean beneficial terms of trade for Australia specifically. So basically, manufacturing has stagnated, and declined as a percentage of total output, which includes commodities. Manufacturing industries as an employer have declined quite sharply – as I can personally attest to. I’ve worked in five different factories in my life, all of which have since closed down – for which I take no responsibility.
Jacinta: So there would be a lack of skilled workers in manufacturing, unless… do we make solar panels here? And what about the old car factories we had here – Mitsubishis and Holdens, remember? Though I presume making EVs would require a whole different skill-set, and besides, wouldn’t it be largely automated?
Canto: Well, in February – that’s 2022 – the Australia Institute posted a highly optimistic media release entitled ‘Australia ready to become sustainable EV-making powerhouse: new research’. And with the new federal government elected in May, this hope, expressed in a report from the AI’s Carmichael Centre, Rebuilding Vehicle Manufacturing in Australia: Industrial Opportunities in an Electrified Future, may actually be realised, at least partially. But before I explore that report – solar photovoltaic manufacturing in Australia. A recent (early July) Guardian article reports that ‘China controls over 80% of the global photovoltaic (PV) solar supply chain, with one out of every seven panels produced worldwide being manufactured by a single factory’. And China is actually increasing production, so as to dominate the market. Diversification is urgently required. Meanwhile, Australia is suffering a labour shortage in the field. The International Energy Agency (IEA) has found that ‘one in three installation jobs in Australia – including electricians and installers – were unfilled and at risk of remaining unfilled in 2023’. Tindo Solar is our only home-grown PV manufacturer, and is expanding its output, but clearly this is dwarfed by China’s production. Also there’s a problem with expending production here because, currently, it actually creates more carbon emissions. We need to ‘create renewables with renewables’, which local experts are saying is now more cost-effective than ever. So, back to the report on vehicle manufacturing in Australia. It’s a job trying to access the full report, so I’ll rely on the media release. It describes our country as ‘uniquely blessed’ to rebuild our car manufacturing capabilities, retooled to EVs, but this will require essential government input – a view very much consistent with Griffith’s. Here are some of the recommendations from the report:
- Establishing an EV Manufacturing Industry Commission
- Using tax incentives to encourage firms involved in the extraction of key minerals – primarily lithium and rare earths – with local manufacturing capabilities, especially emerging Australian EV battery industries
- Introducing a long-term strategy for vocational training, ensuring the establishment of skills to service major EV manufacturers looking to set up operations Australia
- Offering major global manufacturers incentives (tax incentives, access to infrastructure, potential public capital participation, etc) to set up – especially in Australian regions undergoing transition from carbon-intensive industries
- Introducing local procurement laws for the rapid electrification of government vehicle fleets
Jacinta: So, as Griffith points out, we need to do some lobbying for this ourselves. Here in SA, we have a sympathetic state government as well as a federal government keen to make up for lost time, or at least saying all the right things. Where do we start?
Canto: The Clean Energy Council has a website that encourages everyone to get educated (they cite a number of resources such as Renew Economy and ARENA), to spread the word, and of course to actually invest in renewable energy, which we, as impoverished public housing renters, aren’t in a great position to do, though we are trying to get our Housing Association to explore renewable options, and to lobby the government in our name.
Jacinta: I think I’m starting to feel more optimistic…
References
Saul Griffith, The big switch: Australia’s electric future. 2022
Difference Between Black and Brown coal
Nem Watch
Australia ready to become sustainable EV-making powerhouse: new research
https://www.carmichaelcentre.org.au/rebuilding_vehicle_manufacture_in_australia
movements in nuclear fusion: ITER
the world’s biggest clean energy project? ITER in southern France
Geographical, the magazine of the UK’s Royal Geographical Society, had an article in its April 2021 edition entitled ‘Caging a Star’, all about the International Thermonuclear Experimental Reactor (ITER) project in Provence, France. Thermonuclear fusion has of course been talked up as an ultimate solution to our energy needs for decades, to the extent that it’s become something of a joke, but in the meantime, practical movements are underway. In fact, they’ve been under way for a long time. An international contract was signed in 1986 to implement research on fusion, though it took another twenty years to agree on the site for ITER. The project now involves 35 countries – largely WEIRD ones (Western Educated Industrial Rich Democracies), producing 85% of global GDP. It’s a long-term project, certainly, but it’s being taken seriously, and construction is happening, big-time.
With the IPCC having recently come out with its 2021 report, nations are looking to their targets and feeling concerned – some more than others (wake up Australia). Boštjan Videmšek, the author of the Geographical article, assesses the current situation in stark terms:
70% of all CO2 emissions pumped into the atmosphere are created through energy consumption; 80% of all the energy we consume is derived from fossil fuels. The EU has formally pledged to start producing half of its electric energy from renewable resources by 2030. By 2050, the bloc’s members are planning to hoist themselves into a fully carbon-neutral society. But, given current trends, this seems like wishful thinking. Renewable energy resources simply won’t be enough for the task.
The ITER project came out of the closet, so to speak, in late July 2020, when the heart of the project, the tokamak, began to be assembled onsite – though construction of various elements of the program have been going on for years. A tokamak is a toroidal or doughnut-shaped chamber, controlled by huge, powerful magnets, in which hydrogen plasma is manipulated to produce energy according to Einstein’s mass-energy equation. We all know, I hope, that fusion is constantly happening in the sun, and in all suns throughout the universe, and that its energy is essential to our existence, but ITER’s scientists are hoping to improve on the sun’s processes. Hydrogen collisions inside the sun don’t always result in fusion – the fusion process is quite slow. Recognising this, researchers looked to isotopes of hydrogen to speed up the process. Hydrogen’s most common form, consisting simply of a proton and an electron, is called protium. However, there are two other isotopes, deuterium and tritium, containing an additional one and two neutrons respectively. The best form of fusion reaction for producing energy is DT fusion, using deuterium and tritium. This produces more energy, at a lower temperature. The problem is with the tritium, a highly radioactive and unstable isotope, which is both rare and expensive, at about US$30,000 per gram. The rarity, though, is related to low demand, and there is potential for ITER to produce its own supply of the isotope.
Of course, none of this is expected to be ready in the near future. ITER is essentially a proof-of-concept project for future power plants, and is expected to spend a decade in testing, finalising in around 2035. Those future power plants are already ready and waiting, at least in terms of design. The key to achieving fusion is a sufficiently high temperature (150,000,000 degrees celsius!) and high particle density, for an optimum fusion rate. Containment of the volatile plasma will also, of course, be an issue. ITER’s experiments will also be about capturing and utilising the energy produced. As Videmšek describes it:
The idea is that heat will build up along the sides of the tokamak, where it will be captured by the cooling water circling the reactor. As in a normal power station, the heat will be used to produce steam and – by way of turbines and alternators – electricity. The water will eventually be released with the help of vast cooling towers. These have already been put in place…
The science itself, as researchers told Videmšek, is straightforward enough, but the infrastructure, the international nature of the project, the politics and the funding can all provide obstacles. The siting in Provence has helped, as France has successfully embraced nuclear fission technology for decades, and the project is a boon for the Provençal economy. And of course there’s the global warming issue. The IPCC has just released its 6th Assessment Report and, among other findings, has confirmed what we here in Australia have experienced regarding extreme weather events:
Human-induced climate change is already affecting many weather and climate extremes in every region across the globe. Evidence of observed changes in extremes such as heatwaves, heavy precipitation, droughts, and tropical cyclones, and, in particular, their attribution to human influence, has strengthened since the Fifth Assessment Report (AR5).
The report argues that, ‘unless deep reductions in carbon dioxide (CO2) and other greenhouse gas emissions occur in the coming decades’, this scenario of extreme weather events will continue into the foreseeable future. These deep reductions, it seems, are a matter of political will, not to mention recognition of the crisis, which is clearly not universal. The way that many nations, including some of the most powerful and impactful on climate, have dealt with the clear and present threat of the SARS-CoV-2 virus, doesn’t provide much cause for optimism. If the ITER project, mostly funded by EU nations, goes off without a hitch over the next few decades, it may just put another nail in the coffin of our self-destructive exploitation of fossil fuels. Better late than never I suppose…
References
Boštjan Videmšek, ‘Caging a star’, in Geographical, April 2021
https://www.ipcc.ch/report/ar6/wg1/#SPM
a bonobo world? 4
a group of Rapa Nui people, photographed in 1895
Chapter 1 – Culture (continued)
It isn’t known precisely when the Polynesians first settled on Rapa Nui, but there appears to have been regular habitation there from about 800 years ago. It’s clear from the numerous moai – we know of at least 900 – carved by the Rapa Nui people, and the great platforms, or ahu, upon which they were displayed, that they had developed a sophisticated, creative culture during the first few centuries after their arrival (building upon eastern Polynesian traditions found on other islands), but it seems this was very much in decline by the time of Roggeveen’s 1722 visit. It’s the causes of this decline that are very much the subject of modern debate.
Rapa Nui is a volcanic island, and was thickly forested in earlier times, as researchers have found through paleobotanical analysis. However, by the early eighteenth century, almost all of the trees were gone. The controversy revolves around whether and how much the Rapa Nui people engaged in self-destructive behaviour, in relation to their natural resources, resulting in population collapse. According to Deutsch, following Bronowski, the self-destructive behaviour of the natives was a counter-example to the ‘ascent of man’ or ‘the beginning of infinity’ that Deutsch admires in the form of the short-lived but brilliant ancient Athenian culture, and in modern scientific humanity. However, I feel that both Deutsch and Bronowski have over-simplified and thus seriously distorted Rapa Nui culture to make their case, and that these kinds of distortions can be generalised to show that many of us still treat other cultures in a dismissive and hubristic way, when a more open and sympathetic understanding can only improve our own culture, at a time when, arguably, our future isn’t quite as rosy as we would like it to be.
In his account of the Rapa Nui cultural collapse – which certainly did occur – Jared Diamond is more sympathetic. With the help of scientific associates, he examined a number of variables affecting deforestation on Pacific islands. They found that deforestation is more severe on: 1) dry islands than wet islands, 2) cold high-latitude islands than warm equatorial islands, 3) old volcanic islands than young volcanic islands, 4) islands without aerial ash fallout than islands with it, 5) islands further from Central Asia’s dust plume, 6) islands without makatea (coral reef rock) than islands with it, 7) low islands than high islands, 8) remote islands than islands with near neighbours, and 9) small islands than big islands
Collapse, Jared Diamond, p116
Based on these criteria, and his finding that Rapa Nui ticked 8 out of 9 of the above boxes, Diamond came to this judgment:
In short, the reason for Easter’s unusually severe degree of deforestation isn’t that those seemingly nice people really were unusually bad or improvident. Instead, they had the misfortune to be living in one of the most fragile environments, at the highest risk for deforestation, of any Pacific people. For Easter Island, more than for or any other society discussed … we can specify in detail the factors underlying environmental fragility.
Of course, questions remain, Such as: Why would a culture destroy a resource (its trees) when it relied on that resource so heavily? How, exactly, was that resource destroyed? Was it actually the result of human activity, and if so, what kind of activity? And there are other questions about the Rapa Nui population itself. It seems to have imploded in the period between the building of ahu and moai, and the incursions of Europeans in the eighteenth century. However, there’s much disagreement about the population of Rapa Nui at its height, with some claiming it may have been as much as 15,000 – a large number for such a tiny island, when the inhabitants had to depend entirely on that island’s resources. But these numbers are very rubbery, as is the length of time that these Polynesian adventurers had been inhabiting the island – anywhere from 800 to 2700 years. I am reminded of similar uncertainties and debates about Australia’s first inhabitants; dates range from 45,000 to 80,000 years, and the populations are anybody’s guess, but that doesn’t stop researchers from guessing. Surely there would have been wide fluctuations in the populations over time, as the climate warmed and cooled. In any case, the Rapa Nui population was supposedly reduced to approximately 3000 by 1722, though how this figure was arrived at is a mystery. Clearly Roggeveen didn’t take a count, and the Rapa Nui people were not in a position to keep written records. Unfortunately everything about this island’s pre-European history is subject to ongoing debate.
Evidence clearly shows that some 21 species of trees and the island’s land birds had disappeared by the time of Roggeveen’s visit. The rats brought to the island may have been the cause of much but certainly not all of the plant devastation, and the loss of many of the biggest trees may have affected the inhabitants’ ability to build canoes for fishing expeditions. Research has shown that the Rapa Nui people’s diet contained far less fish and seafood than that of other Polynesian Islanders. However, claims by Diamond and others, of a breakdown within the culture leading to internecine warfare and even cannibalism, have been controversial. The obsidian blades found on the island may have been fashioned for farming rather than fighting. More importantly, for my own thesis of the superiority of co-operative societies, (bonobos as opposed to chimps), recent research seems to be converging on a view that contradicts Diamond’s story of increasing competition in the form of ever more monumental statue building in a heavily hierarchical society. We may never know for sure, but anthropologist Carl Lipo had this to say on the research in 2018:
Lipo explained that there is no archaeological evidence for the control of resources or any hierarchical distribution of resources, which is leading to a new narrative about the pre-contact Rapa Nui society: that the island was not dominated by massive chiefdoms, and rather, communities shared resources without any prehistoric warfare.
I cannot of course vouch for the truth of this new interpretation of Rapa Nui culture, despite hoping that it’s more accurate. What is definitely true and uncontroversial is that the arrival of Europeans, and the diseases they brought with them, was far more devastating for the Rapa Nui people – as well as Australia’s Aborigines – than anything they ever did to themselves.
References
Collapse, Jared Diamond 2005
The beginning of infinity, by David Deutsch, 2011
https://en.wikipedia.org/wiki/Easter_Island
https://www.eurekalert.org/pub_releases/2020-02/bu-eis020620.php
climate change – we know what we should be doing
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
the SUV abomination, or when will we reach peak SUV?
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?
on dinosaurs and the Cretaceous climate
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
fish deaths in the lower Darling – interim report
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.
why are our river fish dying?
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.