• CaptDust@sh.itjust.works
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    1 month ago

    Are there models for 3c or 4c? From what I see, the world ain’t gonna do shit until entire countries become tangibly uninhabitable.

    • hydroptic
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      1 month ago

      I doubt anything will happen even then.

      Well, nothing useful at least – I’m sure that with the current meteoric rise of the extreme right many things will happen, but they’ll be more of the “death camp” variety than the “fixing the climate” variety

      edit: I think high-emission models (ie models that assume we’re going to do jack fucking shit and emissions will keep rising, which frankly seems probable) have predicted average temperature rises of 4 – 5°C. I’m trying to dig up some sources, hang on

      Revenge of the Edit:
      the following refer to the global mean screen temperature[1] at the end of the century for the most pessimistic SSPs[2]

      • CanESM5’s prediction is around 20 – 21°C, giving an anomaly of ~5 – 6°C
      • CNRM-CM6-1 gives global mean screen temps of around 18 – 19°C, so an anomaly of ~3 – 4°C
      • I think UKESM1-0-LL had an anomaly of around 3.5 – 5°C but I’m too tired to read that paper and can’t seem to find the relevant figures
      • ditto for GFDL-CM4

      The Edit Strikes Back:

      The IPCC’s 6th Assessment Report (AR6) includes data from older and usually less sensitive versions (ie. very often more optimistic…) of the models above plus a ton of others, and its Physical Science Basis report’s policymaker summary had this handy table:

      Note that climate models are just that, models. We know they still have a lot of biases and they’re not perfect, but they do already predict historical climate really well, and it should be telling that the better the models get, the worse the predictions tend to be



      1. temperature measured at a standardized height using a “Stevenson screen”. Current global mean screen temperature is around 15°C ↩︎

      2. “Shared Socioeconomic Pathways”, standardized modeling scenarios ↩︎