Lamont Weekly Report, September 28, 2018

    This week has been Climate Week in New York City (, and a Sarah Fecht story posted to our web site on Tuesday describes six options for decreasing one’s personal carbon footprint ( Among the six are eating less beef – illustrated by a photo of Mo Raymo eating chicken – and selecting wind rather than jet fuel as a means of reaching a vacation destination – illustrated by a selfie Robin Bell took from the mast of her sailboat.

    On Monday, Nandini Ramesh successfully defended her Ph.D. thesis on “Questions raised by the global warming hiatus: The predictability of tropical Pacific decadal variability and subsurface warming of the tropical Atlantic Ocean,” completed under the supervision of Mark Cane and Richard Seager. In addition to Mark and Richard, Nandini’s committee included Ryan Abernathey, Michael Tippett from the Department of Applied Physics and Applied Mathematics, and Laure Zanna from the Department of Physics at the University of Oxford. Nandini will be heading west for a postdoctoral position with Bill Boos at the University of California, Berkeley (

    Also on Monday, Lamont was visited by Lassina Zerbo, the Executive Secretary of the Comprehensive Test Ban Treaty Organization. Dr. Zerbo, who earlier this year received the 2018 Award for Science Diplomacy from the American Association for the Advancement of Science (, was in New York this week for meetings of the United Nations General Assembly. A geophysicist by training, Dr. Zerbo met with a group of Lamont’s seismologists and gave a presentation on the CTBTO and nuclear test monitoring to a broad audience.

    Among the topics of Dr. Zerbo’s discussion with Lamont seismologists were the findings reported in two papers posted online last week in Seismological Research Letters on small aftershocks of the most recent and largest North Korean nuclear test in September 2017. The authors – permutations of David Schaff, Won-Young Kim, Paul Richards, and two colleagues at the Korea Meteorological Administration in Seoul – demonstrated on the basis of waveform correlations and spectral amplitude ratios that 13 aftershocks lie along a 700-m-long fault-like structure and display earthquake source mechanisms, consistent with tectonic events induced by the earlier explosion. The papers provided an important demonstration of the power of seismic forensic methods to discriminate earthquakes from explosions at small magnitudes and in a politically sensitive setting. A Kevin Krajick story on the results from the two papers was posted on our web site on Monday (, and Haaretz picked up the story the next day (

    On Monday, the Proceedings of the National Academy of Sciences published online a paper by Dorothy Peteet, Jonathan Nichols, Tim Kenna, Louisa Liberman, and colleagues on the vulnerability of marshes in the New York City region to reductions in mineral sediment flux following urbanization. From a reconstruction of the sedimentation history of marshes in Jamaica Bay over the past three centuries, Dorothy and her coauthors showed through measurements and models that mineral sedimentation has markedly decreased since 1800, and although the flux of organic matter has increased over the same period by amounts sufficient to outpace sea level rise, the lack of marsh-stabilizing minerals has led to weakness and edge failure of the area’s marshes. Their work points to the steps needed to mitigate and reverse marsh loss in this and other drowning estuary settings. A story by freelance writer Aline Reynolds on the paper’s findings is on our web site (

    Late last week, the Hayabusa2 spacecraft in orbit about the near-Earth asteroid Ryugu deployed two small “rovers” onto the asteroid to acquire images and explore the surface. Given the extremely low gravitational acceleration, the rovers have no wheels but rather hop by applying a torque to the surface ( The Hayabusa2 spacecraft, built and operated by the Japan Aerospace Exploration Agency, is scheduled to land next year on Ryugu, thought on the basis of spectral reflectance measurements to consist of primitive carbonaceous material, and return samples to Earth in late 2020.

    Lamont scientists in the news this week included Joaquim Goes, interviewed for about a 7-minute portion of an episode of Public Television’s SciTech Now that aired Monday on the topic of harmful algal blooms in the Arabian Sea ( Adam Sobel was quoted in a feature story Tuesday in Newsweek on the role of climate change in contributing to the severity of and rainfall totals from large tropical storms such as Hurricane Florence ( Yesterday, a Rebecca Fowler interview of Ed Cook on the history of the Tree-Ring Laboratory, the compiling of large-scale drought atlases, and the applications of those records to understand the processes that control hydroclimate variability ( was added to our web site.

    Next week, Columbia University’s Postdoctoral Research Scientists, Postdoctoral Research Fellows, and Associate Research Scientists will have the opportunity to vote on whether they wish to be represented by the Columbia Postdoctoral Workers and United Automobile, Aerospace and Agricultural Implement Workers of America (CPW-UAW). The election will be held on Tuesday, October 2, and Wednesday, October 3. Voting on the Lamont Campus will be held from 11 am to 1 pm on both days in Room 113 of the Geoscience Building. Information on some of the issues associated with unionization has been posted both by Columbia University ( and the union (

    In the meantime, our Earth Science Colloquium speaker this afternoon will be Lamont and DEES alumna Brenda Ekwurzel, Senior Climate Scientist and Director of Climate Science at the Union of Concerned Scientists ( Brenda’s seminar is part of the Distinguished Alumni Lecture series established and managed by the Lamont Alumni Board. Brenda will be speaking on “Global surface temperature and sea level rise from emissions traced to major industrial carbon producers.” I hope that you will join me for her talk.