Robert McLachlan

Robert McLachlan FRSNZ is Distinguished Professor in Applied Mathematics at Massey University and is an advocate for stronger action on climate change.

Why emissions pricing cannot do it alone - Planetary Ecology

Nov 16, 2021

By David Hall and Robert McLachlan There is strong agreement among economists that emissions pricing should play a central role in climate change policy. New Zealand has had a price on some carbon emissions through its Emissions Trading Scheme since 2010, although (COVID excepting) emissions have not yet fallen. Recently the scheme has been strengthened through higher prices, now NZ$65 per tonne of CO2, and a falling cap on emissions. It remains a central plank in our climate change response. It’s been argued that the ETS should be our only mechanism to cut emissions, and that it will deliver the required cuts in the cheapest and most reliable way. The cap on emissions can even lead to absurd claims that any specific cut isn’t necessary, since total emissions will be the same regardless. (If you don’t fly, someone else … Read More

COP26: New Zealand’s new climate pledge is a step up, but not a ‘fair share’ - Planetary Ecology

Nov 02, 2021

As the Glasgow climate summits gets underway, New Zealand’s government has announced a revised pledge, with a headline figure of a 50% reduction on gross 2005 emissions by the end of this decade. This looks good on the surface, but the substance of this new commitment, known as a Nationally Determined Contribution (NDC), is best assessed in emissions across decades. New Zealand’s actual emissions in the 2010s were 701 million tonnes (Mt) of carbon dioxide equivalent. The carbon budget for the 2020s is 675Mt. The old pledge for the 2020s was 623Mt. The Climate Change Commission’s advice was for “much less than” 593Mt, and the new NDC is 571Mt. So yes, the new pledge meets the commission’s advice and is a step up on the old, but it does not meet our fair share under the … Read More

Climate explained: how much of the world’s energy comes from fossil fuels and could we replace it all with renewables? - Planetary Ecology

Sep 15, 2021

How are fossil fuels formed, why do they release carbon dioxide and how much of the world’s energy do they provide? And what are the renewable energy sources that could replace fossil fuels? Fossil fuels were formed over millions of years from the remains of plants and animals trapped in sediments and then transformed by heat and pressure. Most coal was formed in the Carboniferous Period (360–300 million years ago), an age of amphibians and vast swampy forests. Fossilisation of trees moved enormous amounts of carbon from the air to underground, leading to a decline in atmospheric carbon dioxide (CO₂) levels — enough to bring the Earth close to a completely frozen state. This change in the climate, combined with the evolution of fungi that could digest dead wood and release its carbon back into the air, brought … Read More

Who pays? Who changes? - Planetary Ecology

Aug 27, 2021

Let me introduce you to the good life. Climate solutions are often judged not just by whether they work – that is, by whether they reduce emissions – but also by whether they support a “just transition”. As Sam Huggard of the New Zealand Council of Trade Unions writes, “the costs of the necessary changes that deliver all of us a more stable climate must be spread evenly and not fall heavily and disproportionately on workers, particularly those in carbon-exposed industries.” New Zealand has joined international declarations to that effect, and set up a “Just Transitions” unit in the civil service, to ensure that the process is “fair, equitable and inclusive [and] that the Government works in partnership with iwi, communities, regions and sectors to manage the impacts and maximise the opportunities of the changes brought about by the … Read More

Lawyers challenge New Zealand’s proposed emissions budgets as inconsistent with the 1.5℃ goal - Planetary Ecology

Jul 07, 2021

New Zealand’s Climate Change Commission is facing its first legal hurdle, as a group of 300 climate-concerned lawyers seek judicial review of the processes it used to calculate carbon budgets in its recently released advice to government. Carbon budgets are a cornerstone of New Zealand’s climate change response under the Zero Carbon Act and lie at the heart of the commission’s advice package. They specify the allowed emissions over successive five-year periods, initially up to 2035. The advice calls for net emissions of all greenhouse gases to fall 27% between 2019 and 2030. The Lawyers 4 Climate Action group claims the commission has misinterpreted pathways in Intergovernmental Panel on Climate Change (IPCC) reports in its calculations, making its advice inconsistent with the act, especially regarding the goal to limit global temperature rise to 1.5℃. Read More

New plastic ban: Interview with Trisia Farrelly - Planetary Ecology

Jul 01, 2021

On 27 June, the New Zealand Government announced the phase-out of some hard-to-recycle and some single-use plastics. Robert McLachlan talks to Massey University’s Trisia Farrelly, a tireless campaigner against plastic waste. Trisia: I’m an anthropologist at Massey University, I wear quite a few hats around New Zealand and internationally on plastic pollution, which I’ve been researching since 2016. Robert:  And here I thought it was a lifetime passion! You’re an anthropologist… so are you trying to save the world, or just study how it works? Trisia: Save it! One piece of plastic at a time. Robert:  The talk you gave recently described everything from your plastic-free year all the way up to the UN. Trisia: Yes, multiscale! My personal journey started with a film, I watched the Clean Bin Project. The directors were in New Zealand … Read More

So it begins: The Climate Change Commission’s advice to government and what happened next - Planetary Ecology

Jun 23, 2021

What’s that? You wanted action, not just words, on climate change? And you wanted it now, not next year or the year after? How about something big, really big, maybe also diving right into the heart of an emotional, touchstone issue – say, the private car?  Welcome to the EV subsidy. The New Zealand government has surprised and delighted electric vehicle advocates by announcing significant direct subsidies for electric vehicles – both all-electric and plug-in hybrid, whether new or used but newly imported) of up to $8625. These take effect in just a few weeks time, on 1 July 2021. From 2022 they will be replaced by a revenue-neutral ‘feebate’, in which higher-emitting vehicles pay a fee, and lower emitting vehicles (including some petrol cars) receive a rebate. That year … Read More

Climate explained: when Antarctica melts, will gravity changes lift up land and lower sea levels? - Climate: Explained

May 04, 2021

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change. If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz I’ve heard the gravity changes when Antarctica melts will lower the seas around New Zealand. Will that save us from sea level rise? Robert McLachlan, Massey University The gravitational changes when Antarctica melts do indeed affect sea levels all over the world — but not enough to save New Zealand from rising seas. The ice ages and their effects on sea level, geology, flora and fauna were topics of intense scientific and public interest all through the 19th century. Here’s how James Croll explained the “gravity effect” of melting ice in his 1875 book Climate and Time … Read More

Why did New Zealand’s CO2 emissions blow out so spectacularly in 2019? - Planetary Ecology

Apr 18, 2021

Every year in April, the trees start changing colour, the clocks go back an hour, and the national greenhouse gas figures are released and promptly forgotten. They take fifteen months to prepare, so by the time they come out it’s very easy for commentators to point out that they are out of date. Even now that the national media are running several new climate change stories every day, this one seems to pass us by. Not only are the figures out of date, they are also highly technical and hard to interpret: the year-to-year changes might be influenced by one-off factors like the weather, while the long-term trends have been subject to the changing winds of climate policy. The Ministry for the Environment does an amazingly thorough job of reporting greenhouse gas emissions. The latest release includes a 633 … Read More

Submit! Submit! Submit! - Planetary Ecology

Mar 25, 2021

Yes, it’s time to submit to the Climate Change Commission on their draft advice to the government, if you haven’t done so already. Submissions close on 28 March 2021.   Rod Carr / Portrait of Leo Tolstoy by Ilya Repin @NZAHParallels pic.twitter.com/enU91wnhVJ — Robert McLachlan (@nzcpe) February 28, 2021 Actually, Tolstoy can teach us a thing or two about climate change. See Michaelson 2011, Morally Differentiating Responsibility for Climate Change Mitigation: An Analogy with Tolstoy’s” Master and Man”, Business & Professional Ethics Journal, pp. 113-136, and “How Tolstoy’s War and Peace can help us understand history’s complexity“, History News Network, December 2019.   Folks – you have 7 days left to submit to the Climate Change Commission’s draft advice. Here’s a big thread with all of the template submissions … Read More