Tropical cyclones, climate, and consensus, cont’d

I’ve written about what I’ve called the “proto-consensus” on tropical cyclones (AKA hurricanes, typhoons) under anthropogenic warming before (e.g. here and here). On Sunday, Nature Geoscience published a Review entitled “Tropical cyclones and climate change” [full paper here] by Thomas Knutson, John McBride, Johnny Chan, Kerry Emanuel, Greg Holland, Chris Landsea, Isaac Held, James Kossin, A. K. Srivastava, and Masato Sugi that succinctly covers the state of play, reiterating that the evidence seems to be increasingly pointing to a warmer world with less frequent yet more powerful hurricanes:

…future projections based on theory and high-resolution dynamical models consistently indicate that greenhouse warming will cause the globally averaged intensity of tropical cyclones to shift towards stronger storms, with intensity increases of 2–11% by 2100. Existing modelling studies also consistently project decreases in the globally averaged frequency of tropical cyclones, by 6–34%. Balanced against this, higher resolution modelling studies typically project substantial increases in the frequency of the most intense cyclones, and increases of the order of 20% in the precipitation rate within 100 km of the storm centre…

More if/when I have time.

[h/t Andrew Freedman]

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18 responses to “Tropical cyclones, climate, and consensus, cont’d

  1. Umm… read the WHOLE paper.

  2. What were their conclusions about past tropical cyclones?

  3. Just wondering if they found any anthropogenic signals in the historical tropical cyclone data, that’s all.

    • You’re not “wondering” anything. Why the pretense? Your initial response to my post had no mention of that and was clearly worded as though I somehow mischaracterized the paper, which I did not.

      I’m genuinely curious- what prompts you to do this sort of thing?

  4. The paper is based on theory and models, both of which are unproven as yet, and I wanted to know how their model and theory fit with the historical record.

  5. It was just a question. No need to get worked up about it.

  6. Sean, you are being disingenuous, that is very obvious with your exchange thus far here.

    The models work very well in characterizing the intensity of the TCs– predicting their exact path is another story, but the response of TCs to environmental parameters is well understood, both using observations and models. For example, high OHC is a necessary condition for TCs, we know that from studying past storms. We also know from observations that, all other things being equal (e.g., vertical wind shear), as OHC increases so does storm (wind) strength.

    These modeling studies are attempting to understand the net impact of increased wind shear and OHC will have on TC strength and frequency.

    If you per chance know of a superior way of quantitatively and objectively predicting how complex processes in an equally complex system will play out, then please let Drs. Emanuel and Knutson and others who have devoted many years of their careers to addressing this problem. They eagerly await your insight.

  7. As I don’t believe Emanual or Knutson would give a whit about my opinion and being that I do not have their paper in front of me presently, can you tell me if they make a projection of how many joules the OHC will increase per year?

  8. Sean, have you read the paper? They do not speak specifically to OHC. Also, to which basin are you referring, or are you talking globally? Go to the AMS web site and search for hurricanes and oceanic heat content.

    This paper is a meta analysis of all observational and modelling work undertaken on TCs to date and how TCs might respond to a warmer planet. If you want specific information then you’ll have to consult the many, many references listed in Table S1 and Table S2.

  9. Thank you. I’ll refer to those tables.

  10. Landsea and Emanuel on the same paper? Thanks for bringing it up. If this paper contains wording and interpretation that both can agree on, then the paper gives a good indication of where the field is right now.

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