Tag Archive for Varekamp

Volcanic Lake Study by Varekamp, Former Students, Published in Geology

Joop Varekamp

Joop Varekamp

Johan “Joop” Varekamp, Harold T. Stearns Professor in Earth Science, professor of earth and environmental studies, is the co-author of an article published in Geology, March 2021.

The study, titled “Volcanic Carbon Cycling in East Lake, Newberry Volcano, Oregon,” focuses on the bubbling East Lake, the site of the Newberry Volcano, and the geological implications of the carbon reactions happening there.

Varekamp co-authored the article with graduate student Christina Cauley and former students: Hilary Brumberg ’17, Lena Capece ’16, Celeste Smith ’19, Paula Tartell ’18, and Molly Wagner MA ’19. The team researched this geological phenomenon from 2015 to 2019, and they are currently preparing several longer papers on their Newberry lakes findings.

Varekamp’s research centers around volcanic lakes, mercury pollution, and rising sea levels.

Students, Alumni to Make Presentations at Geological Society of America Meeting

Wesleyan students, graduate students, and recent alumni will present research posters during the annual Geological Society of America meeting Oct. 26–30. The virtual event will allow for a five-minute presentation followed by a five-minute period to answer questions.


Earth and environmental sciences graduate student Yu Kai Tan ’20 and Andy (Dick Yee) Tan ’21 will present their poster, titled “Freshwater Mussels in North America: Museum Collections and Pre-Industrial Biogeography,” at 5:15 p.m. Oct. 29. Their advisors are Ann Burke, professor of biology, and Ellen Thomas, Harold T. Stearns Professor of Integrative Sciences, Smith Curator of Paleontology of the Joe Webb Peoples Museum of Natural History, and University Professor in the College of Integrative Sciences. Listen to the presentation in advance online here.

Varekamp Plots Pandemic, Measures Growth Curves in US, Italy

varekamp map

In this linear graph, Professor Joop Varekamp shows logged plots of coronavirus time versus death data in Italy (green) and the United States (blue). The straight-line segments represent exponential growth, and the curved arrays occur after social distancing rules and lockdowns were imposed. Extrapolation of the straight line for the United States (deep blue line) would have reached 1 million casualties (black circle) around April 21 if the U.S. had not imposed social distancing rules, according to Varekamp.

Last March, Johan (Joop) C. Varekamp, Harold T. Stearns Professor of Earth Science, intended to teach an ore deposit and formation class in Italy; however, the COVID-19 pandemic caused him to stay near campus.

Nevertheless, Varekamp kept a keen watch on Italy. With a fascination with the pandemic’s wildfire spread, Varekamp began plotting coronavirus data from both the United States and Italy to see how their growth curves compared.

“Infectious diseases follow initially exponential growth patterns until measures are taken to limit transmission or a vaccine becomes available,” Varekamp said. “I wanted to know how disease propagation compares to population growth, which I teach in some detail in my classes.”

On May 7, Varekamp shared his ongoing Coronavirus Plot Maps with the campus community through Wesleyan’s Community Forum. His study features some of the differences in the progression of the disease in the two countries that may provide some insights “and possibly some dark thoughts about our future.”

Varekamp suggested that if social distancing rules are weakened too early, the disease will pick up where it left off at the exponential end. “This will all be repeated until about 60–70% of the population has been infected with the disease,” he said. “Only then the virus burns itself out, to some degree as a result of lack of non-immune individuals, and transmission rates will decrease to values below one.”

He also stated that if no social distancing had been ordered in the U.S. in late March, the U.S. would have stuck to its exponential growth pattern, and close to 1 million people would have died by the end of April.

If he’s able to safely fly internationally next year, Varekamp hopes to have another attempt at teaching the EU-coordinated ore deposit class at the University of Bologna.

“It is hard to see how all of this evolves,” he said.

Wesleyan Group Attends Field Workshop, Gathers Volcano Samples in Italy

Pictured from left, Joop Varekamp, Molly Wagner, Celeste Smith ’19, and Christina Cauley explore Italian lakes while attending the International Summer Meeting on Volcanic Lakes in June.

This summer, three Wesleyan students and one faculty member attended a field workshop in Basilicata, Italy, where they presented research, collected data, and visited an extinct volcano containing two bubbling crater lakes.

The group collected samples from crater lakes Monticchio Piccolo (foreground) and Monticchio Grande.

The International Summer Meeting on Volcanic Lakes, hosted by the International Association of Volcanology and Chemistry of the Earth’s Interior, took place June 25–29 and focused on the theme “Different perspectives and approaches to studying a volcanic lake.” Basilicata is home to the 3,350-foot-high Mount Vulture (pronounced “Vool-tor-eh”), which last erupted 40,000 years ago.

The Wesleyan attendees included Department of Earth and Environmental Sciences (E&ES) graduate students Christina Cauley and Molly Wagner; E&ES and environmental studies major Celeste Smith ’19; and Joop Varekamp, the Harold T. Stearns Professor of Earth Science, professor of environmental studies, professor of earth and environmental sciences, and professor of Latin American studies. Varekamp also is the Smith Curator of Mineralogy and Petrology of the Joe Webb Peoples Museum of Natural History. They joined more than 25 other participants from Italy, Germany, and Hungary.

The meeting consisted of one long day of scientific presentations in a 12th-century abbey (including talks by Smith, Wagner, and Varekamp), two days on crater lakes Monticchio Grande and Monticchio Piccolo collecting in situ data and samples, and a day of culture, with a trip to the nearby ancient town of Matera.

The group also collected materials specifically for Smith’s senior thesis, including water samples for mercury analyses and a 2.5-foot long sediment core from the most active bubbling lake.

After the field meeting, Smith went to the Institute for Ecosystem Studies at Lago Maggiore near the Swiss border to section her core samples, and then went on to Potsdam, Germany, to subsample an existing sediment core from these lakes.

“Celeste’s thesis topic is to obtain mercury degassing records of this dormant volcano over thousands of years, which will help to establish the natural background mercury flux into the ambient world,” Varekamp explained.

Lefkowitz ’12, Thomas, Varekamp Co-Author Chapter On Volcanic Lakes

Based on the senior thesis of Jared Lefkowitz ’12, “A Tale of Two Lakes: The Newberry Volcano Twin Crater Lakes, Oregon, USA,” was published online, Nov. 25, by the Geological Society of London, U.K, as part of the volume, Geochemistry and Geophysics of Active Volcanic Lakes. The study is co-authored by Lefkowitz; Ellen Thomas, research professor in earth and environmental science; and Johan Varekamp, the Harold T. Stearns Professor in Earth Science. Varekamp also is professor of environmental science, adjunct professor in Latin American studies, and chair of the Geological Society of America’s Limnogeology Division. Thomas also is the University Professor in the College of Integrates Sciences.

The chapter examines the complex ecosystems of Newberry Volcano’s two small crater lakes, East Lake and Paulina Lake, which are of interest to scientists because of the presence of highly toxic components and the signs gas-charging in East Lake. “These factors present natural hazards, which may change when new volcanic activity is initiated,” Varekamp explained. The presence of nearby “seismic triggers or disrupted lake stratification gives scientists a situation to monitor, as these factors can cause sudden intense CO2 degassing in the very different chemistries and gas contents of the two lakes.”

The authors’ abstract is online here.

Additionally, Varekamp contributed papers on Taal Lake in the Philippines and on the Copahue Volcano crater lake in Argentina. Both of these chapters will be published in the same volume in the upcoming weeks.

Paper on Guilford, Conn.’s Sea Level by Varekamp, Thomas, 2 Alumnae Receives 93 Citations

A research paper co-authored in 1995 by Johan Varekamp, the Harold T. Stearns Professor of Earth Science; Ellen Thomas, research professor of earth and environmental science; and Wesleyan alumnae Koren Nydick ’95 and Alyson Bidwell ’95 has returned to the spotlight.

The paper, “A Sea-level Rise Curve from Guilford, Connecticut, USA,” originally published in Marine Geology, was cited last month in another paper on sea-level rise in the Proceedings of the National Academy of Sciences of the United States.

Professor Varekamp admits that the “paper has done remarkably well, with 93 citations, not bad at all for a senior thesis-based article. The inclusion in this PNAS study is the icing on the cake.”

The paper developed from Nydick and Bidwell’s senior thesis work in salt marshes in nearby Guilford, Conn. As a testament to the quality of this work, a group of scientists from Boston University, Yale and Rutgers reproduced Nydick’s study two years ago with additional resources and found an identical sea level rise curve.

After earning her PhD and pursuing a post-doctoral career in ecology, Nydick now works as the science coordinator for Sequoia and Kings Canyon National Parks. Incidentally, a Smithsonian scientist funded by NASA recently contacted Nydick to inquire about the carbon core data from her thesis study for a wetlands carbon storage project.

“I am proud to note that some of my former students who are now professors or practicing scientists in their own right, have their undergraduate thesis articles among their most cited papers,” Varekamp said.

Varekamp Leads Invited Talk at Geophysical Union Meeting


Johan “Joop” Varekamp

Johan “Joop” Varekamp, the Howard T. Stearns Professor in Earth Science, led an invited talk at the American Geophysical Union (AGU) meeting in San Francisco, Dec. 2015.

The earth and space science community participated in discussions of emerging trends and the latest research. The session, which was co-authored by former Wesleyan E&ES graduate student Lauren Camfield, focused on the 2012 eruption of the Copahue volcano in Argentina.

Due to the success of the invited talk on Volcanic Hydrothermal Systems, Varekamp will be a co-editor for a special issue of a journal based on that session. As part of his role as chair-elect of the Committee on Geology and Public Policy of the Geological Society of America (GSA), he will be interviewing five candidates in Washington D.C. for the position of congressional fellow.

Varekamp, Gilmore Co-Author Articles on Argentina’s Copahue Volcano

Joop Varekamp, the Harold T. Stearns Professor of Earth Science, professor of earth and environmental sciences, and Marty Gilmore, the George I. Seney Professor of Geology, professor and chair of professor of earth and environmental sciences, are the co-authors of two book chapters published in Copahue Volcano (Springer Publishers, September 2015)

Copahue Volcano is part of Springer Publishers’ “Active Volcanos of the World” series. Varekamp is the lead author on a chapter with Jim Zareski MA‘14 and Lauren Camfield MA’15. Gilmore and Tristan Kading MA’11 are co-authors with Varekamp on another chapter dealing with terrestrial environments as analogs for Mars. A third chapter, on acid fluids, was written by Varekamp with an Argentinian collaborator. 

Since 1997, Varekamp has worked with Wesleyan undergraduate and graduate students almost every year at Copahue Volcano in Argentina. This project is reaching its closing stages, and has led to 10 peer reviewed published articles, most co-authored with students, four book chapters, six MA theses, and eight senior theses. All these students have subsequently obtained higher degrees in E&ES fields and are currently employed in the broad field of geochemistry and/or volcanology. Varekamp is now focussing his studies on the Newberry volcano in Oregon.

Varekamp Elected Chair of Geology, Public Policy Committee

Joop Varekamp

Joop Varekamp

Johan “Joop” Varekamp, the Harold T. Stearns Professor of Earth Science, professor of earth and environmental sciences, was elected to be chair of the Geology and Public Policy Committee (GPPC) of the Geological Society of America (GSA). The group prepares position statements for GSA (e.g., on fracking, climate change). Varekamp has already made six congressional visits in March, visiting the offices of Senators Richard Blumenthal, Elizabeth Warren, Ed Markey and Representative Rosa DeLauro. He does similar work as chairman of the board of the Connecticut Fund for the Environment / Save the Sound.

Varekamp also was elected to be the chair of the LimnoGeology (‘lakes’) division of GSA for the next two years, which involves organizing conferences and sessions at annual GSA meetings, and editing special volumes on lakes.

In addition, Varekamp received funding through the Keck Geology Consortium for a research project on the two crater lakes of Newberry volcano in Oregon. Varekamp will visit the lakes this summer with a group of student researchers from Wesleyan, Amherst, Colgate and Smith College.

Varekamp Authors 2 Chapters in Volcanic Lakes Book

Volcanic Lakes. (Image courtesy of Springer Science+Business Media)

Volcanic Lakes. (Image courtesy of Springer Science+Business Media)

Johan “Joop” Varekamp, the Harold T. Stearns Professor of Earth Science, professor of earth and environmental sciences, is the author of two chapters in Volcanic Lakes, published by Springer Science+Business Media, 2015. He worked on the chapters during his sabbatical in Bristol, U.K., in 2013.

Varekamp’s chapters are titled “The Chemical Composition and Evolution of Volcanic Lakes” and “Volcanic Lakes.” Five other authors also contributed to the “Volcanic Lakes” chapter.

Volcanic lakes are natural features on the planet. The changing water compositions and colors of these lakes over time provide insights into the volcanic, hydrothermal and degassing processes of the underlying volcano.

This book aims to give an overview on the present state of volcanic lake research, covering topics such as volcano monitoring; the chemistry, dynamics and degassing of acidic crater lakes; mass-energy-chemical-isotopic balance approaches; limnology and degassing of Nyos-type lakes; the impact on the human and natural environment; the eruption products and impact of crater lake breaching eruptions; numerical modeling of gas clouds and lake eruptions; thermo-hydro-mechanical and deformation modeling; CO2 fluxes from lakes; volcanic lakes observed from space; biological activity; continuous monitoring techniques, and other aspects.

Studies by Varekamp, Thomas Published in Paleoceanography


Joop Varekamp

Ellen Thomas

Ellen Thomas

Wesleyan faculty Joop Varekamp and Ellen Thomas are among the authors of a paper on rates of sea-level rise along the eastern U.S. seaboard titled “Late Holocene sea level variability and Atlantic Meridional Overturning Circulation,” published in the journal Paleoceanography, Volume 29, Issue 8, pages 765–777 in August 2014. Varekamp is the Harold T. Stearns Professor of Earth Science, professor of earth and environmental sciences and professor of environmental studies. Thomas is research professor of earth and environmental sciences at Wesleyan, and also a senior research scientist in geology and geophysics at Yale University.

Ellen Thomas discovered that microfossils, such as this  foraminifera fossil, reveal that warm oceans had less oxygen.

Ellen Thomas discovered that microfossils, such as this foraminifera fossil, reveal that warm oceans had less oxygen.

Pre-20th century sea level variability remains poorly understood due to limits of tide gauge records, low temporal resolution of tidal marsh records, and regional anomalies caused by dynamic ocean processes, notably multidecadal changes in Atlantic Meridional Overturning Circulation (AMOC). In the study, Varekamp and Thomas examined sea level and circulation variability along the eastern United States over the last 2,000 years, using a sea level curve constructed from proxy sea surface temperature records from Chesapeake Bay, and 20th century sea level-sea surface temperature relations derived from tide gauges and instrumental sea surface temperatures.

Thomas also is a co-author of a paper titled ‘I/Ca evidence for upper ocean deoxygenation during the PETM‘ published in the Paleoceanography, October 2014.

In this paper, Thomas suggests that the Paleocene-Eocene Thermal Maximum (PETM), a potential analog for present and future global warming, may help in such forecasting future deoxygenation and its effects on oceanic biota. Forecasting the geographical and bathymetric extent,

Varekamp, Thomas Author Chapters on Long Island Sound Reference Volume

Joop Varekamp and Ellen Thomas

Joop Varekamp and Ellen Thomas co-authored chapters in this new book on the Long Island Sound.

Joop Varekamp and Ellen Thomas are the authors of three chapters included in a reference volume for Long Island Sound. The book, Long Island Sound: Prospects for the Urban Sea, is published by Springer in 2013. Varekamp is the Harold T. Stearns Professor of Earth Science, professor of earth and environmental sciences, professor of environmental studies. Thomas is research professor of earth and environmental sciences.

Varekamp co-authored a chapter titled “Metals, Organic Compounds and Nutrients in Long Island Sound: Sources, Magnitudes, Trends and Impacts,” and another chapter titled “The Physical Oceanography of Long Island Sound.” Thomas co-authored a chapter titled “Biology and Ecology of the Long Island Sound.”

Varekamp and Thomas worked on the book for about six years.  The last comprehensive Long Island Sound book was published in the early 1970s.

“We hope that it will be the reference volume for Long Island Sound for some decades to come,” Varekamp said.