Research Interests of Alan Robock



Collaborators: Brian Toon, Julie Lundquist, Nicole Lovenduski, and Yunping Xi (University of Colorado); Chuck Bardeen (NCAR); Jonas Jägermeyr (Columbia University); Lili Xia, Gal Hochman, Joshua Coupe, and Hainan Zhang (Rutgers University)

In the 1980s much of my work addressed the problem of nuclear winter, the climatic effects of nuclear war, demonstrating long-term (several year) effects with a computer model, disproving the dirty snow effect, and discovering observational evidence of surface cooling due to forest fire smoke plumes in the atmosphere. I am now once again doing research in this area, using modern climate models to look at the climatic effects of regional and global nuclear conflicts, funded by the Open Philanthropy ProjectOur latest work shows that even a "small" regional nuclear conflict could have severe global climatic effects, that there are still enough nuclear weapons in global arsenals to produce nuclear winter, and that the impacts would last for a decade.  This is the most serious environmental threat faced by humans and demands immediate policy attention.  If you are a scientist, you can join me on the Physicists Coalition for Nuclear Threat Reduction to work on policy changes.  Even Fidel Castro was interested.


Collaborators: Ben Kravitz (Indiana University), Lili Xia and Brendan Clark (Rutgers University), Simone Tilmes (NCAR), Daniele Visioni (Cornell University), Jonas Jägermeyr (Columbia University), and Haynes Stephens (University of Chicago)

Funded by NSF and SilverLining, we are evaluating the efficacy and consequences of proposed schemes to reduce incoming solar radiation to counteract global warming by injecting aerosol particles into the stratosphere or brightening marine clouds.  Our recent papers describe climate model simulations and the benefits, risks, and costs of stratospheric geoengineering, and the agricultural impacts of geoengineering.  Visit our Rutgers Impact Studies of Climate Intervention (RISCI) lab and for the Geoengineering Model Intercomparison Project (GeoMIP).

For my latest PowerPoint on climate intervention (102 Mb), click here.

By the way, chemtrails are not real.  Contrails are.  See


Collaborators:  Joshua Coupe (Rutgers University), Brian Zambri (MIT), Anja Schmidt (University of Cambridge), and Michael Mills (NCAR)

We were funded by NSF to study the effects of volcanic eruptions on climate using computer models and data analysis.  Our papers on volcanic eruptions and climate include studies of winter warming from large tropical eruptions, climatic effects of high-latitude eruptions (including how they have produced reduced precipitation and famine in Africa and Asia), radiative forcing from volcanic stratospheric aerosol clouds, evaluation of the volcanic record in ice cores, effects of supervolcanoes, impacts of large volcanic eruptions on El Niño and how volcanic eruptionsproduced the Little Ice Age.

I have produced a PowerPoint presentation of the effects of volcanic eruptions on climate that can be used for teaching undergraduate and graduate classes.  It is 222 MB, and you can get it by clicking here.  You will also need the movie, pin.AVI.  Visit for the Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP) and for the Stratospheric Sulfur and its Role in Climate activity.

Prepared by Alan Robock ( - Last updated on January 4, 2021