Around one year after my post on the issue, another study was flagged to me: “Latent Heating Is Required for Firestorm Plumes to Reach the Stratosphere” (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022JD036667). The study raises another very important firestorm dynamic, that a dry firestorm plume has significantly less lofting versus a wet one due to the latent heat released as water moves from vapor to liquid—which is the primary process for generating large lofting storm cells. However, if significant moisture can be assumed in the plume (and this seems likely due to the conditions at its inception) lofting is therefore much higher and a nuclear winter more likely.
The Los Alamos analysis only assesses a dry plume—and this may be why they found so little risk of a nuclear winter—and in the words of the authors: “Our findings indicate that dry simulations should not be used to investigate firestorm plume lofting and cast doubt on the applicability of past research (e.g., Reisner et al., 2018) that neglected latent heating”.
This has pushed me further towards being concerned about nuclear winter as an issue, and should also be considered in the context of other analysis that relies upon the Reisner et al studies originating at Los Alamos (at least until they can add these dynamics to their models). I think this might have relevance for your assessments, and the article here in general.
Hi Stan + others.
Around one year after my post on the issue, another study was flagged to me: “Latent Heating Is Required for Firestorm Plumes to Reach the Stratosphere” (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022JD036667). The study raises another very important firestorm dynamic, that a dry firestorm plume has significantly less lofting versus a wet one due to the latent heat released as water moves from vapor to liquid—which is the primary process for generating large lofting storm cells. However, if significant moisture can be assumed in the plume (and this seems likely due to the conditions at its inception) lofting is therefore much higher and a nuclear winter more likely.
The Los Alamos analysis only assesses a dry plume—and this may be why they found so little risk of a nuclear winter—and in the words of the authors: “Our findings indicate that dry simulations should not be used to investigate firestorm plume lofting and cast doubt on the applicability of past research (e.g., Reisner et al., 2018) that neglected latent heating”.
This has pushed me further towards being concerned about nuclear winter as an issue, and should also be considered in the context of other analysis that relies upon the Reisner et al studies originating at Los Alamos (at least until they can add these dynamics to their models). I think this might have relevance for your assessments, and the article here in general.