INTERESTING👉🏽: Due to the way the international community's agreement to tackle aviation emissions is structured, the Coronavirus pandemic *could* potentially have lasting repercussions for reduced sectoral emissions...
Quick Thread...
Context:
✈️Global air traffic has dipped about 20% since the same time last year.
✈️It was expected to be around 5% (give or take) higher than the year previous... so a 20% drop is HUGE.
✈️Hard to say how much this drop (which started in January) will reduce 2020 emissions...
More Context:
✈️ Globally, aviation accounts for about 2.5% of GHG emissions.
✈️ INTERNATIONAL AVIATION accounts for about 65% of total emissions. Since Int'l aviation is NOT included in National Climate plans, the world came up with... CORSIA.
This agreement is actually quite complex, but the most important thing to note is that it aims to CAP the sub-sector's emissions at 2020 levels. It promises NOT to emit any more CO2 than the sector emitted in 2020, mainly by charging a fee on flights which would support OFFSETS.
SO, right off the bat, you can see why a massive decline in air traffic in 2020 would be problematic from an industry's point of view - it means that the baseline drops. If flight demand returns to normal, or if the growth rate returns, in a few months, say, the offset gap is ⬆️.
Those who planned the terms of the agreement were clever though... and the baseline is actually defined as an average of international emissions from 2020 AND 2019. So it remains to be seen just how much COVID-19 reduces emissions over this 24 month period...
Nevertheless, aviation demand has doubled over the last two decades and before this pandemic demand was expected to double again over the next 2 decades...
Just look at the yearly growth since 2016, followed by the current drop (dark blue):
There are all sorts of loop-holes in CORSIA, the most obvious being the conceptual problem with Offsets in the first place, another being its 'Route-based approach'...
Nevertheless, a lower baseline for the entire agreement ultimately means - at least in theory - less emissions from the aviation sector... not just in 2020, but forever HENCEFORTH...
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🧵Here's a little story about a scientific paper from 20 years ago that sought to cast doubt on @MichaelEMann's famous 'Hockey Stick' warming graph by reworking his original data set. Now, 20 years out *even this same revised dataset* now very clearly shows.... a Hockey Stick!
2) In 1998 Mann and colleagues published a very important paper in Nature. They conducted an impressive study compiling temperature reconstructions for the last 6 Centuries, and found a startling 'hockey stick' shape: The world was warmer than it had been in nearly 600+ years!
3) Some years later, two Canadians wrote a paper refuting these findings, thus casting doubt on the modern human influence in global warming🤦♂️. They asked Mann for the original data (which he kindly supplied), and then claimed that the temperature reconstructions had errors.
A very important paper was published yesterday, discussing the feasibility of limiting global warming to 1.5°C when considering a range of existing constraints.👇
The findings are indeed daunting, but maybe not as hopeless as many on this website seem to imply...
Quick 🧵
2/ The study reviews chances of keeping global warming to within Paris Agreement bounds of 1.5C to 2.0C given the latest understandings of 5 key constraints: geophysical; technological; institutional; socio-cultural; and economic...
3/ They find that while it is possible - despite existing constraints - to remain below 1.6 °C of peak warming (which is a 'low overshoot' temperature which could eventually be brought back down to 1.5C), the *likelihood* of doing so is now below 50%...
2/ There've been many June heatwaves like this in the US before. And, the daily mean temp anomaly for Wednesday, June 19th (the peak day of the heat dome) wasn't very exceptional in much of the US East... (for that given day of the year).
3/ If we look at the month of June across the US SOUTHEAST going back to 1895, we can see that the region has been plenty warm before during the month of June (this record goes up to 2023)!
1) The thread noted a divide between what I called “accelerationists” who were sounding alarm that 2023’s remarkable warming was the beginning of SOMETHING NEW, and those I (later) called “observationalists”, who claimed 2023’s extreme warmth fits within EXPECTED WARMING trends.
2) These positions continue to be expressed. @MichaelEMann, for instance, is adamant that “the truth [about global warming] is bad enough”; that the warming we saw in 2023 can be explained by known climate physics; and that 2023 fits within the modelled warming.
This post by @FoodProfessor claims that the Trudeau Government purposely built the @ClimateInstit and @SP_Inst as part of its "lobbying machine" and that they are "mandated to advocate blindly" for the carbon tax.
This is a baseless claim.
Thread...🧵
1) This story starts in 1988 when the Mulroney government created an Independent advisory council of experts called the National Roundtable on the Environment and the Economy. For 25 years it produced numerous reports on environmental policy, advising governments.
2) Then in 2013 the Harper government cancelled the NREE's funding because it did not like the advice it was receiving (in particular regarding carbon pricing). News story about it here: cbc.ca/news/politics/…
I don't know if the left has ever been unified, but today there seems to be a massive and growing rift about the environment - and especially climate - amongst socialists.
I now worry these differences are irreconcilable...
2. The discord seems to come down to fundamentally different worldviews shaping interpretations and definitions of modernity, development, progress, capitalism, justice, Marx's intentions, strategy, the future...
Many people seem absolutely fed up with "the other side". FED. UP.
3. The Degrowth Left (and this is sure to be a caricature of 'the ideology', not thinking of any one individual) seems FED UP with what it believes Ecomodern Socialism is: a sort of capitalism-as-usual in disguise...