17 May 2022

1.5 degrees Paris climate target not ‘safe or appropriate’ given climate tipping point risks, ‘major rethink’ required: new report

Download the report

Climate tipping points in the Antarctica, the Arctic and the Amazon are at risk of being reached before or at the current level of global warming of 1.2 degrees Celsius, requiring a “major rethink” of global climate goals and the action necessary to achieve them, according to a report released today.

A ‘tipping point’ is a threshold at which a small change initiates a larger, more critical change, taking the climate system from one state to a discreetly different state, which may be abrupt and irreversible. 

Climate Dominoes: Tipping point risks for critical climate systems,is published by Breakthrough - National Centre for Climate Restoration. Co-authored by former head of the Australian Coal Association Ian Dunlop and Breakthrough’s Research Director, David Spratt, the report outlines the scientific evidence that critical climate tipping points are already being reached in Antarctica, the Arctic, Greenland Ice Sheet, the Amazon rainforest and for coral reefs.

05 May 2022

Tullamarine’s dream of a third runway is an emissions nightmare

by Mark Carter

Aviation is gearing up to be once more the fastest growing source of greenhouse gas emissions. And MelbourneAirport is planning to play its part.

It’s now asking the federal transport minister to approve a third runway that will create cumulative emissions,estimated at around 160 million tonnes carbon dioxide equivalent (CO2-e) out to 2046 from additional flights.

Australia Pacific Airports (Melbourne) Pty Ltd (APAM), Melbourne Airport’s owner, seems to be in denial about our climate reality. It understates Third Runway emissions, its assessment of climate risk to the runway is cavalier, and it ignores realistic threats to passenger growth.

03 May 2022

Are renewables decreasing global fossil fuel use?

by David Spratt


Recently Shane White, who blogs at worldenergydata.org, alerted me to a recent report, Boom and Bust Coal 2022: Tracking the global coal plant pipeline, compiled by by Global Energy Monitor in association with CREA, E3G, Sierra Club, SFOC, Kiko Network, CAN Europe, LIFE, and Bangladesh Groups. The report points to a net increase in the global coal-power fleet of 18.2 gigawatts (GW) in 2021.

Whilst the pace of solar and wind energy construction is accelerating, it is not making significant inroads into the quantity of emissions from fossil-fuel based energy systems. Recently Mark Diesendorf from the University of NSW noted that: "We must confront a hard fact: In the year 2000, fossil fuels supplied 80% of the world’s total primary energy consumption. In 2019, they provided 81%.” 

22 April 2022

“Climate greatest threat to Australia’s security,” ex-defence chief says

Former Chief of Australian Defence Force, Admiral Chris Barrie during a press conference at the Fuel Security Summit in Sydney. (AAP Image/Bianca De Marchi).

by Michael Mazengarb, first published at RenewEconomy

National security experts have called on Australian voters to use the federal election to support candidates that back strong action on climate change, saying Australia has “squandered” the last two decades.

Speaking at the Smart Energy Council’s Emergency Fuel Summit in Sydney, retired admiral Chris Barrie described climate change as the single biggest threat to Australia’s national security. Barrie currently serves on the Australian Security Leaders Climate Group and said the group saw national climate policy failures as putting Australia at risk.

“We consider that climate change now represents the greatest threat to the future and security of Australia,” Barrie said.

24 March 2022

Retired senior defence leaders name climate disruption as "clear and present danger", call for 2030 decarbonisation goal

by David Spratt

Seventeen senior retired Australian defence leaders have described climate disruption as an "existential threat" and a "clear and present danger", calling for accelerating action with a 2030 decarbonisation goal.

The call came in an open letter to Australia's political leaders, which was also published as a full-page statement in the national The Australian newspaper on 23 March.  Amongst the signatories are Admiral Chris Barrie, the former chief  of the Australian Defence Force, and Air Vice-Marshal John Blackburn AO, the former deputy chief of the Royal Australian Air Force.   The letter is available here.

22 March 2022

Existential climate risk management on ClimateGenn

by David Spratt

Recently I had the opportunity to speak with journalist Nick Breeze, who writes for The Ecologist as well as running his excellent ClimateGenn site (genn.cc). 

The podcast /video are now available. Nick describes our conversation as:

"In this ClimateGenn episode I am speaking with Research Director of the Breakthrough National Centre for Climate Restoration in Melbourne, David Spratt, about assessing climate risk and why incremental tweaks to reduce emissions are failing us.

"We also discuss IPCC forecasts, political failure, and how change is possible but it requires a huge mobilisation of resources, coupled with public and political participation and leadership of the Zelensky variety.

11 February 2022

Don't miss Saul Griffith in Melbourne 20 February


For our Melbourne and Victoria readers...

Saul Griffith's new book ‘The Big Switch’ lays out a detailed blueprint – optimistic but feasible – for decarbonising our economy while creating millions of new jobs and a healthier environment. 

Join Saul for this special Sustainable Living Festival Forum as he reveals exactly what it will take to rapidly transform our infrastructure to zero emissions. 

 Hosted by Walkley Award-winning journalist and broadcaster, Paul Barclay, the event will be recorded and broadcast on ABC Radio National's 'Big Ideas' program.

1pm Sunday 20 February @ The Capitol

Book at https://events.humanitix.com/the-big-switch-australia-s-electric-future

 More information: http://www.slf.org.au/event/big-switch-australias-electric-future/ 

"I’m a scientist, engineer, inventor, and father who wants to leave my kids a better world. The data convinces me that it is still rational to have hope." — Saul Griffith 

02 February 2022

Have tipping points already been passed for critical climate systems? (7) Summing up: Faster than forecast, cascades loom

by David Spratt

Seventh in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Image: MaxPixel

Reflecting on the evidence presented in this tipping point series, a number of conclusions may be drawn:

  1. At just 1.2°C of warming, tipping points have been passed for several large Earth systems.  At just 1.2°C of global average warming, tipping points have been passed for several large Earth systems.  These include Arctic sea ice, the Greenland Ice Sheet, The Amundsen Sea glaciers in West Antarctica, the eastern Amazonian rainforest, and the world’s coral systems. The world will warm to 1.5°C by around 2030, with additional warming well beyond 1.5°C in the system after that. Yet even at the current level of warming, these systems will continue to move to qualitatively different states. In most cases, strong positive feedbacks are driving abrupt change. At higher levels of warming, the rate of change will quicken. The meme that “we have eight years to avoid 1.5°C and tipping points” should be deleted from the climate advocacy vocabulary. It is simply wrong.

31 January 2022

Have tipping points already been passed for critical climate systems? (6) Permafrost: Beyond the models

by David Spratt 

Sixth in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Permafrost is permanently frozen ground. It covers one-quarter of the land mass of the northern hemisphere, and contains 1.5 trillion tonnes of carbon, twice the amount currently in the atmosphere and triple the amount emitted by human activity since 1850.  Permafrost buried beneath the Arctic Ocean holds 60 billion tons of methane (in structures known as methane clathrates) and 560 billion tons of organic carbon.

Permafrost is releasing significant amounts of greenhouse gases, and feedbacks are under way, but the dynamics are not yet well enough understood to be able to judge whether tipping points have been reached or not.  As previously noted (in part 1 of this series), University of NSW researchers point out that: “We do not know exactly how close we are to a tipping point, or even whether we have already passed it… There are tipping points that while not yet triggered may already be fully committed to.” 

28 January 2022

Have tipping points already been passed for critical climate systems? (5) Coral Reefs: A death spiral

by David Spratt 

Fifth in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Updated 2 February 2022.

Great Barrier Reef bleaching 2016

Ecosystems, including coral reefs, mangroves and kelp forests in Australia, are degrading fast as the world's sixth mass extinction gathers pace. 

Coral polyps are invertebrates similar to minute jellyfish, which build limestone structures, and live in a symbiotic relationship with algae-like unicellular zooxanthellae that reside within the coral structure, and give it colour. The coral provides the algae with a protected environment and compounds they need for photosynthesis. In return, zooxanthellae supply the coral with oxygen, glucose, glycerol, and amino acids, which are the products of photosynthesis. 

26 January 2022

Have tipping points already been passed for critical climate systems? (4) Forests and the Amazon: A faltering carbon sink

by David Spratt

Fourth in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Deforestation in the Brazilian Amazon.
Image: Chatham House
 
 

The plant-based terrestrial biosphere may be understood as including the world’s land-based plants, soils, derived dead organic matter, such as litter, and soil organic matter. 

Plants photosynthesis uses carbon dioxide and water to produce sugar (glucose) and oxygen. Around 30% of the additional carbon dioxide (CO₂) produced by human actions has been drawn down from the atmosphere (mitigated) by increased plant photosynthesis. This adds to the land-based sink of stored carbon. But plants also respire, for example at night and in winter, by converting oxygen and stored glucose back into water and carbon dioxide. 

As the planet continues to warm, a point of warming is reached — the “thermal maximum for photosynthesis” — after which combination of the rate of photosynthesis decreasing and the rate of respiration increasing results in the net flux of CO₂ from the atmosphere decreasing.

24 January 2022

Have tipping points already been passed for critical climate systems? (3) Greenland and the Arctic: Abrupt change

by David Spratt

Third in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Broken-up Arctic sea-ice
“The Arctic is screaming”, says Mark Serreze, Arctic climate expert at the US National Snow and Ice Data Center.

Arctic warming is racing ahead of the worst-case estimates, now heating four times faster than the global average, and the region is undergoing abrupt climate change, understood as a transition of the climate system into a different mode on a time scale that is faster than the responsible forcing. In other words, it has passed a tipping point for rapid, system-level change. 

Researchers say that the Arctic “is currently experiencing an abrupt climate change event …  climate models underestimate the abruptness of the recent changes observed in the Arctic (and) climate models underestimate this ongoing warming”. [Models do not account well for warming due to sea-ice loss, but losing the reflective power of Arctic sea ice in the summer months would advance the 2ºC threshold by 25 years”.]

20 January 2022

Have tipping points already been passed for critical climate systems? (2) West Antarctica and the "doomsday" glacier

 by David Spratt

Second in a series.    Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Thwaites Glacier fractures. Image: NASA
The Thwaites Glacier in West Antarctica has an eastern ice shelf 45 kilometres wide as it flows into the Amundsen Sea. On 13 December 2021, scientists announced that the ice shelf is likely to break apart in the next five years or so, resulting in a speeding up of the glacier’s flow and ice discharge, possibly heralding the collapse of the glacier itself, and triggering similar increases across the Amundsen Sea glaciers.

The researchers explain: “Over the last several years, satellite radar imagery shows many new fractures opening up… which like a growing crack in the windshield of a car [can] suddenly break apart into hundreds of panes of glass. We have mapped [the] pathway the fractures might take through the ice [and conclude] the final collapse of Thwaites Glacier’s last remaining ice shelf may be initiated … within as little as five years” (emphasis added).

18 January 2022

Have tipping points already been passed for critical climate systems? (1) The basics

by David Spratt

First in a series.   Read 1  |  2  |  3  |  4  |  5  |  6  |  7

Tipping points and potential cascade effects
As global heating reduces the extent of floating Arctic sea-ice each summer, the heat-reflecting ice is replaced by heat-absorbing dark ocean water, adding energy to the Arctic system, driving more melting. This is a “positive feedback”, a self-reinforcing change. Examples abound in the climate system. On Greenland, for example, warming is reducing the height of the ice, and this lower elevation means it will melt more, because the temperature is higher at lower altitudes. 

Sixteen years ago, James Hansen warned that “We live on a planet whose climate is dominated by positive feedbacks, which are capable of taking us to dramatically different conditions. The problem that we face now is that many feedbacks that came into play slowly in the past, driven by slowly changing forcings, will come into play rapidly now, at the pace of our human-made forcings, tempered a few decades by the oceans thermal response time."