While Morrison crab walks to net zero (part III)

Tim Baxter
7 min readJun 9, 2021


(this is part iii of a series. part i is here. part ii is here. it’s okay. this one can wait. read the others first!)

In part I of this series of articles intended to complicate the over-simplified about the Australian Prime Minister’s maybe, possibly, probably not crab walk to net zero, I raised some important first principles about Australia’s role as a cause of the destabilisation of the global climate. The most important thing to remember that Australia has played – and continues to play – an outsized role that destabilisation.

Also, if we don’t manage the fossil fuel problem, there is zero chance of reaching any of the better futures currently available. Plant all the trees you want, there aren’t enough.

In part II, I ran through another substantive principle about reaching a net zero goal. Namely: even with the same net zero date – 2050 for example – the pathway to net zero is critically important to determining the harm down to the global climate.

It’s not like the only thing that’s important is the date. I mean:

All three stylised paths to net zero from part 2 on a single graph. Text boxes point to the fact that the ‘Allergy to Action’ path is more ambitious than the Federal Government’s current projections, which it claims meet its 2030 ambitions. The Slow and steady path emits twice what the Go Hard path does before hitting zero. The Allergy to Acting path emits three times more than the Go Hard path. Text descriptions of the different paths are contained in part 2.

Today, I’m going to build on this with a little more geometry. In order to make a point that most good climate people – I could add many scientists of note to this list when they speak and write clumsily – forget:

2050 is much too late to prevent additional climate harm.

Accepting 2050 as a responsible net zero date from anyone who would offer it borders on morally repugnant.

As of 2020, as a result of human influence on the global climate, the world has warmed by 1.2°C above the average temperature of the years 1850–1900.

A temperature increase of 1.2°C sounds like a relatively small change. But it’s important to remember that the planet we live on is big enough to have born almost the entire history of human endeavour. Yes, we went to the moon a few times, and flew a drone on Mars one day. There are a couple of unmanned satellites out in the Kuiper Belt, too. All else, happened within the space that we have warmed by more than a degree.

Let me be clear. The last time the world faced a calamity more sudden and significant than the one we are causing now, a comet hit Mexico, creating the Chicxulub crater, and wiping out all of the dinosaurs.*

(* Other than the birds. Birds are dinosaurs. Keep up.)

Other than a Velociraptor-killing comet, the closest analogue we have to the change being seen today is the Paleocene-Eocene Thermal Maximum – 55 million years ago. During the PETM, temperatures did end up being higher than we have driven them so far. That said, the 5–8°C shift that occurred in the PETM happened over thousands – more likely tens of thousands – of years. You can count the number of decades it took to deliver the 1.2°C that we have managed on you fingers and toes. And – to be frank – you can count most of it on one hand.

(If you want the TL;DR: on the PETM: This video is great)

Unsurprisingly, this is a change that has had consequences.

Attribution scientists – several of whom I count as friends – will justifiably quibble about whether we can prove that event x would or could not have occurred without climate change in the strict sense. But to be clear, our influence on the global climate is so significant that every weather event we have seen in the past few decades has been caused by human release of greenhouse gas.

Even the most mundane burst of rain or sunny day might have had an equivalent in a world where we hadn’t disrupted the global climate with our burning of coal, oil and gas. However, part of the reason it occurred today was because of climate change.

But even limiting our scope to recent Australian extreme events that have been proved to the satisfaction of climate attribution scientists – who I love, but who are a particular type of person – to have a strong connection to climate change:

  • Drought without precedent in several regards on the east coast of Australia as a result of climate-induced shifts in the Indian Ocean Dipole.
  • The third mass-bleaching of the Great Barrier Reef in five years, a phenomenon that had never been seen at this scale before 1998.
  • Black Summer.

1.2°C is not great. Let’s stop here, or perhaps turn back time a lot.

From today, every delay to the end of coal, oil and gas consumption is worse than the alternative.

In 2018, the Intergovernmental Panel on Climate Change released a special report entitled Global Warming of 1.5°C. To describe it the report as ‘landmark’ or its impact as ‘seismic’ is a cliché and I won’t have it. That said, the beast of a thing cut through the noise and climate denial far better than any IPCC report before or since.

But in several regards, it cut through wrong.

The most obvious example of this is in the ‘12 years to solve climate change’ issue. (For what it’s worth, that was solving it by 2030.)

First, the report never said that. Second, that’s not how this works.

On any metric, there aren’t 12 years to fix this, we are in ‘every cigarette is doing you damage’ territory. If we fix it in 8, that’s better than 12. Twelve is better than 15. Fifteen is better than 20. Etfc.

Every fraction of a degree that we allow the world to warm from today is disasters. Parents will lose children. Children will lose parents. Crops will fail in hungry nations. Floods will take out homes. Lives will be lost. Livelihoods will be lost. Places and species we cherish will be lost.

Also, for what it’s worth, ugly places and ugly species that are essential but that we don’t cherish will be lost.

So, there’s no easy way to tell you this:

The fact that a cohort of scenarios run through a supercomputer that were configured to deliver an outcome that is appreciably worse than today – and with assumptions that might be impossible – clustered around reaching net zero in 2050 does not mean that 2050 is enough.

We’re at 1.2°C, and I lived through Black Summer. As someone in a developed country high above sea level, I’m pretty fjaking sure that it was intolerable. Go on: tell me about how the world will be fine if we manage x°C.

The more the world warms, the worse things are. The biggest determinant of how bad things get is our burning of coal, oil and gas. What if we didn’t.

In part two, I gave you three scenarios, Go Hard, Slow and Steady and Allergy to Acting. What would happen if we did the same thing, but just…. faster.

First we have Allergy to Acting. It was already far more ambitious than what is on offer than the Federal Government, but doubly so now.

Chart displaying the difference between following the Allergy to Acting path, which meets zero with minimal early action by leaving significant emissions reductions for much later, using a net zero date of 2040 and  following the same path but arriving at net zero in 2050. Hitting zero in 2050 emits 60% more before hitting zero than hitting net zero in 2040.

Even under the worst pathway to zero, a 2050 net zero date is significantly worse than a 2040 date. A shift from 2040 to 2050 results in 60% more climate harm.

The Slow and Steady path shows the same kind of pattern. Except there’s something kind of important to note here:

Chart displaying the difference between following the Slow and Steady path, which hits zero after taking equal  emissions reductions each year to the zero date, using a net zero date of 2040 and following the same path but arriving at net zero in 2050. Hitting zero in 2050 under this path emits 56% more before hitting zero than hitting net zero in 2040.

A middling, and pointlessly slow, path to net zero in 2050 is objectively worse than the Allergy to Action path to net zero in 2040. A straight line to net zero in 2050 emits 7% more – on a greenhouse gas equivalent basis [which is an important thing I’ll come back to] – than the highest emitting path I could put before you with a straight face that might hit net zero in 2040.

The Slow and Steady path to net zero in 2050 emits 56% more than a Slow and Steady path to net zero in 2040. That is a lot of extra climate destabilisation.

And then, …

Chart displaying the difference between following the Go Hard path, which hits zero after significant early action but with a thin tail of difficult to abate sectors being dealt with in the later years, using a net zero date of 2040 and following the same path but arriving at net zero in 2050. Hitting zero in 2050 under this path emits 45% more before hitting zero than hitting net zero in 2040.

A deep reduction to 2050 emits less than a Slow and Steady path to 2040. But not a lot less. There is still a greater distance between going hard to 2040 and going hard to 2050 than there is between going hard to 2050 and going slow to 2040.

Every bit of additional harm is optional.

If you reckon a 2050 goal is either necessary – even as a minimum standard – or sufficient, you need to pay closer attention.

(I don’t ask for payment from you, but claps, likes and shares keep me writing, just in case you were wondering.)

Part VI is here.



Tim Baxter

Climate and energy researcher for my day job, but these opinions are written on my own time.