Climate scientist here; stuff like this is dangerously inaccurate.
If we stop emissions tomorrow, the earth will remain around 1.2C above preindustrial temps. If we get to net-zero emissions by 2060 or so, we can still limit warming to well below 2C.
A wide range of studies – including the latest state-of-the-art Earth System Models – all show there isn't much additional warming "in the pipeline" if emissions go to zero. Saying its too late makes folks give up hope; the warming we get is still up to us biogeosciences.net/17/2987/2020/
To elaborate a bit, if we held atmospheric concentrations of CO2 constant, the world would indeed warm another 0.5C or so. But if emissions go to zero, falling levels of atmospheric CO2 counteract additional warming as the ocean equilibrates with the atmosphere.
Similarly, additional warming from reduced sulphate aerosols is counterbalanced by falling short-lived GHGs like methane. This diagram in the recent IPCC Special Report on 1.5C shows the effects of various zero emissions scenarios:
So, at the end of the day the amount of warming we get this century is up to us. We aren't committed to large amounts of additional warming, but at the same time we need to speed up emissions reductions significantly if we want any hope of limiting warming to well-below 2C:
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We've done a major update of our @CarbonBrief CMIP6 explainer to include the latest ScenarioMIP results; up to 36 different CMIP6 models included now, with between 28 and 35 models available in each of the "Tier 1" scenarios (2.6, 4.5, 7.0, and 8.5): carbonbrief.org/cmip6-the-next… 1/8
Here are the latest warming projections (late 21st century vs preindustrial) from CMIP6 models. Note that SSP1-1.9 is included as it has 12 models available, but others (3.4, 6.0) are not shown as they still have very few (< 10) models reporting. 2/8
Some notable changes: the SSP1-1.9 scenario which was designed to limit warming to 1.5C actually succeeds in doing that in the multimodel mean (which was not the case when we had fewer model runs in our initial analysis). Similarly, SSP1-2.6 MMM (barely) limits warming to 2C. 3/8
Ambitious climate policy is going to be a major challenge in a divided government with a conservative court. But that doesn't mean we can't make real progress over the next four years.
A short thread: 1/7
We can continue to make clean energy cheap. There is a strong bipartisan consensus for things like ARPA-E and more spending on RD&D, which is particularly important outside the power sector where clean energy alternatives are less readily available. 2/7
We can still likely pass some big infrastructure bills, modernizing our power grid, enhancing our resiliency to climate change, and create jobs in the process. 3/7
We (@Peters_Glen and I) have a new letter in the Proceedings of the National Academy of Sciences responding to a recent article by Schwalm et al on whether or not the RCP8.5 scenario is appropriate to use for near-term emissions (through 2050): pnas.org/content/early/… 1/15
Their original article suggested that RCP8.5 best matched historical emissions and what they identified as likely future emissions based on the IEA WEO fossil emission data and their own land use assumptions, at least through 2030 (and still reasonably close through 2050): 2/15
We point out that when you only look at fossil emissions (e.g. fossil fuels and industry) this is not the case; IEA projections are much more in line with RCP4.5 or RCP6.0: 3/15
Today I published an op-ed in Politico with @atrembath on why @JoeBiden and @KamalaHarris are right to be skeptical of a fracking ban. It risks reviving coal when we need to phase it out ASAP and could perversely slow clean energy if not done carefully politico.com/news/agenda/20… 1/
As an aside, I really wish op-ed departments would stop rewriting headlines to make them more edgy without your permission. The title we submitted "Why Biden and Harris Are Right to Be Skeptical of a Fracking Ban"... 1.5/13
The op-ed is in part a distillation of this exceedingly long twitter thread the other week, so I'd suggest checking that out for details if you haven't seen it yet:
So, this new paper in Nature has a rather misleading statement in the abstract. It says ecosystem restoration could "sequester 299 gigatonnes of CO2—30% of the total CO2 increase in the atmosphere since the Industrial Revolution". 1/3
However, 299 GtCO2 is only ~15% of human emissions (~2000 GtCO2) since the industrial revolution.
Sequestering 299 GtCO2 would only reduce atmospheric CO2 concentrations by 15%, not 30%. The airborne fraction that applies to our emissions also applies to negative emissions. 2/
This is the same mistake that the Bastien et al paper in Science made last year, conflating sequestration potential with the perturbation of atmospheric CO2 without accounting for sinks. 3/3
A lot of the climate section of the VP debate focused on hydraulic fracturing (e.g. fracking). Its a complex subject – one that I've published a few papers about – and worthy of an exceedingly long twitter thread.
For more, read on! 1/
First, a bit of background about the debate. Fracking primarily occurs on privately owned land, and states rather than the federal gov't have primary jurisdiction over it. That said, the fed gov't can regulate it in some ways (e.g. rules around flaring or fugitive methane). 2/
Fracking is used to produce both oil and natural gas by fracturing shale rocks deep underground. When combined with horizontal drilling it allows for cost-effective extraction of both. 3/