*A long earnest thread*
Here, @GrogsGamut argues that reflexive centrism undermines climate action - I agree!
Unfortunately Greg also:
- makes misleading claims re climate science.
- defends radicalism against 'reason' as he critiques @DrCraigEmerson's call for moderation https://twitter.com/GrogsGamut/status/1198348311977086976

The false claim? Its one you see everywhere. Greg writes: "Thirteen months ago the UN issued a report that concluded we have 12 years to do something to limit climate change, after which it will be too late to keep the rise in temperatures below 1.5C."

Why's that wrong? Well, the '12 years' meme implies that either
a) climate breakdown will happen in 2030, or
b) that all useful action must happen in the next 12 years. Both are wrong. Myles Allen, the relevant IPCC lead author, explains here: https://twitter.com/timinmitcham/status/1119148988010074113?s=20

What the IPCC actually says is that "Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate." Human activities have already caused 0.8°C - 1.2°C warming, & we're heating at around .2°C per decade.

Meanwhile, since most of the warming over the next decade will be caused by CO2 that's already been emitted, and since air pollution is actually masking some warming even if we stopped all pollution today, warming might still pass 1.5°C.

The IPCC also notes: "In model pathways with no or limited overshoot of 1.5°C, global net anthropogenic CO2 emissions decline by about 45% from 2010 levels by 2030, reaching net zeroaround 2050"  So 2030 isn't a magical deadline. It's just one point in a demanding 30yr schedule.

So @grogsgamut's call to "do something" in 12 years actually understates the challenge. The IPCC really suggests that next year, and every year for the next 30, the entire world economy must decarbonise at a pace (about 6-7% per year) that is unprecedented anywhere.

The science hasn't changed: temperatures will keep increasing until net emissions reach zero; the longer we wait the harder it gets; there are no magic deadlines. However, global emissions continue to increase at a rate of almost 2% a year.

So yes, the 2030 claim is bit misleading. But is that necessarily a problem? Mightn't a fake deadline motivate action?  I suspect that's what @GrogsGamut has in mind. But what worries me is that the fake 12-year deadline discourages long term thinking. Three examples:

1. @GretaThunberg warns us that avoiding 1.5°C warming will require that her generation suck "hundreds of billions of tons of your CO2 out of the air with technologies that barely exist". This won't happen within 12 years. But Thunberg is right that we need to start work.

2. Ross Garnaut's report for Rudd/Gillard suggested the world should be spending $100 billion on low-carbon innovation each year. Breakthroughs in smelting, synthetic fuel, batteries, cement, fusion etc won't be finished in 12 years...but innovation policy is no less urgent.

3. IPCC scenarios in which we avoid 1.5°C nearly all require that global electricity supplied from wind, solar AND nuclear power all increase in coming decades. Yet, the 12 yr deadline is used by Greens to argue against zero-emissions nuclear power simply because its 'too slow'.

So why does no major political party (or activist group) have policy on negative emissions or low-carbon innovation? Is it the curse of centrism? Or is it because these policies don't play into sectarian culture wars?

I'm not suggesting anyone should abandon the struggle against coal. But there are plenty of other, less divisive, areas of climate policy where some reasoned, non-partisan radicalism might be possible. @DrCraigEmerson's call to come out of trenches is worth thinking over.