Ben Matthews

  • New here on lemmy, will add more info later …
  • Also on mdon: @benjhm@scicomm.xyz
  • Try my interactive climate / futures model: SWIM
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  • 73 Comments
Joined 10 months ago
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Cake day: September 15th, 2023

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  • I’ve long dreamed of going from Europe to New Zealand by train and boat, but that route is not currently practical / ethical. ( fwiw, I used to know it well, in more friendly days I organised the ‘climate train to Kyoto’ )

    Further south people used the ‘silk road’ route across the Caspian sea - until Azerbaijan closed land borders.
    (note: for info about crossing borders in central asia the forum on caravanistan can help).

    That leaves only the route via Turkey - Iran - Pakistan - India, which is possible (depending your passport and visas) although it’s dodgy across Balochistan. And then, after India, there is also a war in Myanmar. So, can only hope for better times.






  • Indeed I see too much fatalistic doomerism here on Lemmy and it’s boring - waste of potential energy. We can try to explain better - if people want to understand - that climate system is complex, actions don’t give immediately tangible results, there are many sub-systems with inertia, and indeed various types of waves too, but most of this is predictable and the pathways we have to follow are well known.
    By the way about the jet-stream waves mentioned in the article, they have two sides - where I am it’s been cool recently.
    More importantly, seems likely that Chinese emissions are peaking, not because they are so virtuous but because their enormous over-construction bubble involving so much steel and concrete, which was driving global emissions growth, has burst. When I was in climate negotiations years ago, we could never get the chinese to agree to talk about peaking before 2025, yet it happened. Meanwhile renewable energy expands fast around the world.
    However we also reduced a lot of sulphate aerosols (both on land and from ships at sea), so we removed that temporary cooling, then on top of that we had El Niño, and have a peak in the solar cycle. The temperature spike then pushes more CO2 into the atmosphere from forests, soils and ocean, so we get bad news about atmospheric CO2, but such feedbacks happened before and are in the models, it’s not unexpected or out of control yet.






  • Even if we had low-emissions, low-noise, low-accident cars, there’d still be the concrete jungle surface needed to drive them - and loads of emissions to make the steel and cement of highways.
    Although cars carrying four or more people directly to a medium-distance destination can be relatively efficient per pers-km, people buy oversized cars imagining some dream holiday, then use them for daily life on one-person trips that (electric-) bicycles and/or trains could do - car-sharing could help avoid that and solve the EV-range issue (although personally, my dream holidays would be in places with no cars at all).


  • Well, maybe not just wait … Some factors will fall back - e.g. El Niño is a cycle, so are sunspots, ocean patches go round in (big-slow) loops, forests can run out of tinder (for a while). But to be sure to tip the balance of those climate-carbon feedbacks we need to get the temperature down - this could be done quicker by focusing especially on emissions of shorter-lived gases - mainly methane. Cutting out aviation-induced cirrus might also help to cancel some of the warming we got from cutting shipping sulphate - the opposite effect is because low clouds cause net cooling, high clouds cause net warming (depending on angle of sun etc. …). The good news is that models already include most of these factors, the bad news is that models say we have to cut emissions much faster than we do.


  • Global directly-anthropogenic CO2 emissions - things we measure and attribute to countries - have been flat in the period 2019-23 (except for covid dip), and maybe falling this year (due to changes in China). However there are also climate -> carbon feedbacks. The most obvious are forest fires which tend to peak during El Niño years (it’s a repeating pattern - I even remember 1998 seeming bad). Heating also enhances respiration by bugs in soils, and reduces the solubility of CO2 in seawater - the ocean is the largest and most long-term CO2 sink. El Niño also changes ocean circulation temporarily, but I forget which way this impacts CO2 (it’s not trivial - you have to think about the history and future of large patches of water).
    So, if known emissions are flat, but there is a record increase in the atmosphere, that means those feedbacks are worse. It takes a while to disentangle the factors, but this is not a surprise to me.





  • Hi, excuse me for replying so late, but i’ve been away from lemmy for.a while. Well, to summarise, the model calculates the future trajectories, of population, economy, emissions, atmospheric gases, and climate response etc., according to a set of (hundreds of) diverse options and uncertainties which you can adjust - the key feature is that the change shows rapidly enough to let you follow cause -> effect, to understand how the system responds in a quasi-mechanical way.
    Indeed you are right, complexity is beautiful, but hard. A challenge with such tools is to adjust gradually from simple to complex. Although SWIM has four complexity levels, they are no longer systematically implemented - also what seems simple or complex varies depending where each person is coming from, so i think to adapt the complexity filter into a topic-focus filter. Much todo …



  • As it happens I’ve been calculating per capita emissions for 28 years, since COP2. You can see my model here.
    No I certainly don’t include Russia nor Turkey, although europe is more than EU. Korea is indeed notable. Regarding what they call ‘consumption emissions’, you can get such data from Global Carbon Project, on that I’m less an expert but my hunch is that industry emissions are dominated by heavy products like steel and cement for construction (made with help of gigatons of coal), rather than light consumer goods for export. Over-construction is the root of the problem, global emissions will peak (maybe now) as that bubble bursts.