Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”
Abstract
Robock et al. contend that the reasons for Reisner et al. simulations not producing enough black carbon (BC) in the upper atmosphere are as follows: (1) low fuel loads, (2) high surface winds, (3) omission of latent heat release by cloud formation, and (4) short simulation. We resolve (1) with additional simulations over a range of fuel loads, clarify (2) by noting that our surface winds of 2.4 m/s are below the firestorm threshold, agree that addressing (3) requires more research, and (4) short simulations are appropriate since this is when most of the BC emissions that can reach the upper atmosphere occur. While we agree with their assessment that a firestorm was not produced, we demonstrate here why a firestorm is unlikely in dense population centers found in India and Pakistan where concrete structures dominate. Our conversion of all fuel to BC is an upper bound and was the basis of the assertion on maximum global impacts. Furthermore, our study is the first to treat BC generation and lofting with physics–based models underscoring the need to initialize BC in global simulations properly. Reisner et al. and the responses identify critical gaps that must be filled to make any meaningfulmore »
- Authors:
-
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Publication Date:
- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1581574
- Report Number(s):
- LA-UR-19-26224
Journal ID: ISSN 2169-897X; TRN: US2100730
- Grant/Contract Number:
- 89233218CNA000001
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Geophysical Research: Atmospheres
- Additional Journal Information:
- Journal Volume: 124; Journal Issue: 23; Journal ID: ISSN 2169-897X
- Publisher:
- American Geophysical Union
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; nuclear winter; firestorm; pyrocumulusnimbus
Citation Formats
Reisner, Jon Michael, Koo, Eunmo, Hunke, Elizabeth Clare, and Dubey, Manvendra Krishna. Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”. United States: N. p., 2019.
Web. doi:10.1029/2019JD031281.
Reisner, Jon Michael, Koo, Eunmo, Hunke, Elizabeth Clare, & Dubey, Manvendra Krishna. Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”. United States. https://doi.org/10.1029/2019JD031281
Reisner, Jon Michael, Koo, Eunmo, Hunke, Elizabeth Clare, and Dubey, Manvendra Krishna. Sat .
"Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”". United States. https://doi.org/10.1029/2019JD031281. https://www.osti.gov/servlets/purl/1581574.
@article{osti_1581574,
title = {Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”},
author = {Reisner, Jon Michael and Koo, Eunmo and Hunke, Elizabeth Clare and Dubey, Manvendra Krishna},
abstractNote = {Robock et al. contend that the reasons for Reisner et al. simulations not producing enough black carbon (BC) in the upper atmosphere are as follows: (1) low fuel loads, (2) high surface winds, (3) omission of latent heat release by cloud formation, and (4) short simulation. We resolve (1) with additional simulations over a range of fuel loads, clarify (2) by noting that our surface winds of 2.4 m/s are below the firestorm threshold, agree that addressing (3) requires more research, and (4) short simulations are appropriate since this is when most of the BC emissions that can reach the upper atmosphere occur. While we agree with their assessment that a firestorm was not produced, we demonstrate here why a firestorm is unlikely in dense population centers found in India and Pakistan where concrete structures dominate. Our conversion of all fuel to BC is an upper bound and was the basis of the assertion on maximum global impacts. Furthermore, our study is the first to treat BC generation and lofting with physics–based models underscoring the need to initialize BC in global simulations properly. Reisner et al. and the responses identify critical gaps that must be filled to make any meaningful assessment of the probability of global nuclear winter.},
doi = {10.1029/2019JD031281},
journal = {Journal of Geophysical Research: Atmospheres},
number = 23,
volume = 124,
place = {United States},
year = {2019},
month = {10}
}
Figures / Tables:

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