Consequences of Nuclear War – A Lecture by Mark Moldwin

Consequences of Nuclear War

Mark Moldwin

Arthur F. Thurnau Professor  Climate and Space  University of Michigan

US-Norway Fulbright Arctic Chair

University of Bergen

Acknowledge Profs Al Saperstein (Wayne State) and Alan Robock  (Rutgers) for their work and help with this presentation

See this file for all illustrations and text:


Why is a Climate and Space Prof giving a Talk on Nuclear War?

  • Climate Impacts (aerosols, black carbon, ozone destruction, nuclear winter)
  • Anthropogenic Space Weather (EMP and radiation impacts on satellites, electronics,  communication and power grid)
  • 2 minutes to midnight
  • Scientist’s ethical obligation to communicate our work and our moral  responsibility to work for peace

Ronald Reagan:When asked about the  effects of nuclear war in a  February 12, 1985 interview  in the New York Times said,

“A great many reputable scientists are telling us that such a war  could just end up in no victory for anyone because we would wipe out  the earth as we know it. And if you think back to … natural  calamities – back in the last century, in the 1800’s, … volcanoes – we  saw the weather so changed that there was snow in July in many  temperate countries. And they called it the year in which there was  no summer. Now if one volcano can do that, what are we talking  about with the whole nuclear exchange, the nuclear winter that  scientists have been talking about? It’s possible …”

Mikhail Gorbachev:

“Mikhail Gorbachev explains  what’s rotten in Russia”

by Mark Hertsgaard, Sept. 7, 2000

“Models made by Russian and American scientists  showed that a nuclear war would result in a nuclear  winter that would be extremely destructive to all life on  Earth; the knowledge of that was a great stimulus to us,  to people of honor and morality, to act in that situation.”


Today’s arsenal (2019) is about 1/3 of the 1985 arsenal.

It is the equivalent of the explosive power of about

5,000,000,000,000 kg  (11,000,000,000,000 lbs) of TNT.

5,000 MT yield

If we divided this up and gave everyone on the planet his  or her share, each person would have the equivalent of  just under a kT of TNT.

Total yield of all explosive bombs used in World War  II (including         Hiroshima and Nagasaki) = 2-3 MT!

Total yield of all explosive bombs used in all warfare in  the history of the world = 10 MT!



Richard Turco, Brian Toon, Tom Ackerman, Jim  Pollack, and Carl Sagan, 1983:   Nuclear winter:  Global consequences of multiple nuclear  explosions, Science, 222, 1283-1292.

The famous TTAPS paper – one of the two first  climate model simulations of nuclear winter.

Gave Nuclear Winter its name.

Used a single column radiative-convective climate  model which represented the entire Northern  Hemisphere by one column and calculate the  vertical distribution of temperature change for  annual average radiation out to 300 days.

Curt Covey, Steve Schneider,  and Starley Thompson, 1984:  Global atmospheric effects  of massive smoke injections  from nuclear war: Results  from general circulation  model simulations. Nature,  308, 21-25.

Used NCAR GCM to simulate the temperature effects for 20 days for winter, spring, and  summer conditions.


What would be the consequences of a full-scale nuclear war between the        US and Russia?

We use the NASA GISS ModelE atmosphere-ocean general circulation model.

  • 50 Tg or 150 Tg of smoke into the 300-150 mb layer (upper troposphere) over the US and Russia on May 15
  • 30-yr control run, two 10-yr runs (50 Tg or 150 Tg)

What could produce 150 Tg of smoke?

  • standard nuclear winter scenario of 30 years ago
  • entire current arsenal if targeted the same way
  • only 4000 weapons (2017 global arsenals of New START treaty)

Robock et al., 2007b


EMP – Can damage electronics and power distribution systems

  • E1 – very large electric field due to gamma radiation directly impacts space and ground electronic systems
  • E2 –blast wave E-field and particle acceleration and (for HAND) coherent gyration of Compton scattered electrons  can make whole atmosphere a big antenna inducing EMP  that can damage electrical systems (similar frequency to  lightning impacts)
  • E3 – large geomagnetic perturbations can give rise to ground-induced currents also damaging electric grid  (similar frequency to CME driven geomagnetic storms)

“Unless someone like you cares a whole awful lot, nothing is going to get  better. It’s not.”


Dr. Seuss, The Lorax (1971)

U.S. Nuclear Weapon Program Costs

  • Spurred by memo of UK refugee German physicists, U.S./UJ create “Manhattan Project”- 1942-1045
  • Cost: $2 billion ($26B in current U.S.$)
  • $4.5B/year over 10 years for SSP (stockpile stewardship program)
  • 2014- $23.3B for nukes; $20.5B associate costs
  • 2017 latest CBO estimates that existing plans for U.S. nuclear forces would cost $400 billion over the 2017–2026 period


What if India and Pakistan had a nuclear war?

Imagine a skirmish  in Kashmir  escalating, due to  poor communication,  misunderstanding,  panic, and fear.


What would be the consequences of a regional nuclear war using 100 15-kT (Hiroshima-size)  weapons?

This would be only 0.03% of the current world arsenal.

Scenario: Weapons dropped on the 50 targets in each  country that would produce the maximum smoke.

20,000,000 people would die from direct effects, half of  the total fatalities from all of World War II.

Portions of megacities attacked with nuclear devices or  exposed to fallout of long-lived isotopes would likely be  abandoned indefinitely.

5 million tons of smoke injected into the upper atmosphere,  accounting for fuel loading, emission factors and rainout.

Robock, Alan, Luke Oman, Georgiy L. Stenchikov, Owen B. Toon, Charles Bardeen, and Richard P. Turco,  2007: Climatic consequences of regional nuclear conflicts. Atm. Chem. Phys., 7, 2003-2012.

Climate and Space papers:

  1. Covey, S.H. Schneider, S.L. Thompson Global atmospheric effects of massive smoke injections from a nuclear war: results from general circulation model simulations, Nature, 308 (1984), pp. 21-25

Gombosi, T. I., D. N. Baker, A. Balogh, P. J. Erickson, J. D. Huba, L. J. Lanzerotti. Anthropogenic Space Weather. Space

Science Reviews, 2017; DOI: 10.1007/s11214-017-0357-5

Mills, Michael J., Owen B. Toon, Richard P. Turco, Douglas E. Kinnison, and Rolando R. Garcia, 2008: Massive global ozone

loss predicted following regional nuclear conflict. Proc. National Acad. Sci., 105, 5307–5312.

Mills, Michael J., Owen B. Toon, Julia Lee-Taylor, and Alan Robock, 2014: Multi-decadal global cooling and unprecedented  ozone loss following a regional nuclear conflict. Earth’s Future, 2, 161-176, doi:10.1002/2013EF000205.

Özdoğan, Mutlu, Alan Robock, and Christopher Kucharik, 2013: Impacts of a nuclear war in South Asia on soybean and  maize production in the Midwest United States. Climatic Change, 116, 373-387, doi:10.1007/s10584-012-0518-1.

Robock, Alan, 2011: Nuclear winter is a real and present danger. Nature, 473, 275-276.

Robock, Alan, Luke Oman, Georgiy L. Stenchikov, Owen B. Toon, Charles Bardeen, and Richard P. Turco, 2007a: Climatic  consequences of regional nuclear conflicts. Atm. Chem. Phys., 7, 2003-2012.

Robock, Alan, Luke Oman, and Georgiy L. Stenchikov, 2007b: Nuclear winter revisited with a modern climate model and  current nuclear arsenals: Still catastrophic consequences. J. Geophys. Res., 112, D13107, doi:10.1029/2006JD008235.

Robock, Alan, Owen B. Toon, Richard P. Turco, Luke Oman, Georgiy L. Stenchikov, and Charles Bardeen, 2007c: The  continuing environmental threat of nuclear weapons: Integrated policy responses needed. EOS, 88, 228, 231, doi:  10.1029/2007ES001816.

Robock, Alan, and Owen Brian Toon, 2010: Local nuclear war, global suffering. Scientific American, 302, 74-81.  Robock, Alan, and Owen B. Toon, 2012: Self-assured destruction: The climate impacts of nuclear war, Bull. Atomic

Scientists, 68(5), 66-74, doi:10.1177/0096340212459127.

Toon, Owen B., Richard P. Turco, Alan Robock, Charles Bardeen, Luke Oman, and Georgiy L. Stenchikov, 2007:  Atmospheric effects and societal consequences of regional scale nuclear conflicts and acts of individual nuclear  terrorism. Atm. Chem. Phys., 7, 1973-2002.

Toon, Owen B., Alan Robock, Richard P. Turco, Charles Bardeen, Luke Oman, and Georgiy L. Stenchikov, 2007:  Consequences of regional-scale nuclear conflicts. Science, 315, 1224-1225.

Toon, Owen B., Alan Robock, and Richard P. Turco, 2008: Environmental consequences of regional and global nuclear war  in the 21st century. Physics Today, 61, No. 12, 37-42.

Xia, Lili, and Alan Robock, 2013: Impacts of a nuclear war in South Asia on rice production in mainland China. Climatic  Change , 116, 357-372, doi: 10.1007/s10584-012-0475-8.

Xia, Lili, Alan Robock, Michael Mills, Andrea Stenke, and Ira Helfand, 2015: Decadal reduction of Chinese agriculture  after a regional nuclear war. Earth’s Future, 3, 37-48, doi:10.1002/2014EF000283.

See this file for all illustrations and text:


Thanks to Mark Moldwin for kind permission to use this material on the blog.

About ivarjordre

painter, activist, writer, revolutionary, human
Dette innlegget vart posta under Environment, Our global world, Politikk, samfunn og merkt , , , , . Bokmerk permalenkja.

Legg att eit svar

Fill in your details below or click an icon to log in: logo

Du kommenterer no med din. Logg ut /  Endre )

Google photo

Du kommenterer no med Google-kontoen din. Logg ut /  Endre )


Du kommenterer no med Twitter-kontoen din. Logg ut /  Endre )


Du kommenterer no med Facebook-kontoen din. Logg ut /  Endre )

Koplar til %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.