• silence7@slrpnk.netOPM
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    11 months ago

    Most of the exact boundaries for ecological tipping points aren’t known with an 0.1ºC precision. I don’t think we’re going to get something like what you are asking for, just knowledge that each incremental increase in temperature is another step into a minefield.

    • Ben Matthews
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      11 months ago

      True, but in principle we (i.e. big teams) could make impacts functions for each case and combine by integrating over risk (within which, value judgements also make a big difference - but that’s something to learn too). To fit those functions we needed more studies by ESMs with smaller differences at the low end - if you don’t study it, you won’t know it (hence my point years ago - those models are slow, and big committee-run processes even worse).

      • silence7@slrpnk.netOPM
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        11 months ago

        Sure, it would be nice to know, but I don’t see knowing as likely to change policy in any kind of meaningful way. That’s going to take changing who holds power, not incremental knowledge.

        • Ben Matthews
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          11 months ago

          I agree about that too - and think about how to model these power dynamics. Maybe you’re suggesting (by this + posting the original) that we influence politics more by emphasising the crisis, regardless of the shape of that curve of increasing impacts. Such logic could also justify why they like to run high scenarios in ESMs. This doesn’t convince people like me, but I know my way of thinking is not so typical, so maybe you are right.
          Otoh there are some influential people, especially those who trust black boxes of economic optimisation models (there’s another recent thread about that), for whom the lack of such info could effectively provide an excuse for delayed action.

          • silence7@slrpnk.netOPM
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            11 months ago

            My impression is a lot of the high-emissions scenarios being used lets you demonstrate that there is an impact easily, even if the actual date of that impact looks to be somewhat later than under the most likely emissions scenarios.

            And yes, the economic models are particularly awful; DICE has a bunch of assumptions in it about economic impact not affecting sectors which operate indoors and about damage being in the form of a fraction of GDP for that sector. eg: if agriculture is 3% of the economy by value, and it goes to zero, the overall impact is a 3% cut to economic output, even though no food means no economy.