Eric T Sundquist

"As a career student of the carbon cycle, I have come to understand atmospheric carbon dioxide as a critical mediator between many natural processes that sustain life on Earth and many socioeconomic activities that sustain human society"


Eric T. Sundquist has been a Research Geologist with the U.S. Geological Survey (USGS) since 1978.  His research seeks to evaluate and understand the processes that control and respond to changes in the level of CO2 in the atmosphere.  A recipient of the U.S. Department of the Interior (DOI) Superior and Meritorious Service Awards, Dr. Sundquist is a Fellow of the American Association for the Advancement of Science.  He has edited two American Geophysical Union (AGU) Monographs; The Carbon Cycle and Atmospheric CO2: Natural Variations Archean to Present (1985), and, Carbon Sequestration and its Role in the Global Carbon Cycle (2009); and he has served as Editor-in-Chief of the AGU journal, Global Biogeochemical Cycles.  He has served as chair several national scientific committees, including the American Geophysical Union (AGU) Focus Group on Global Environmental Change (2000-2004), the USGS Interdisciplinary Carbon Committee (2008-2011), and the DOI Biological Carbon Sequestration Workgroup (2009-2010).  He has also served as a member of the U.S. Carbon Cycle Scientific Steering Group (2000-2004) and the U.S. Carbon Cycle Interagency Working Group (2004).  He was a coauthor of the U.S. Carbon Cycle Science Plan (1999) and the North American Carbon Program (NACP) Plan (2002), and currently serves as co-chair of the committee to revise the NACP Implementation Plan.  Dr. Sundquist holds a B.A. degree in Geology from Pomona College, and A.M. and Ph.D. degrees in Geological Sciences from Harvard University.

Dr. Sundquist’s research seeks to evaluate and understand the processes that control and respond to changes in the level of CO2 in the atmosphere. His interests include the natural cycling of CO2 and carbon through plants, soils, seawater, rocks, and sediments.  He studies the causes and effects of past geologic changes in atmospheric CO2 levels, and the ongoing effects of human actions on CO2 and climate.

Current research projects:

A principal focus of carbon-cycle research is to understand the historical and present-day carbon mass balance (“budget”) of the response of natural processes to anthropogenic influences.  Dr. Sundquist’s recent work has focused on four salient themes that have emerged from this research: (1) the predominance of emissions from burning fossil fuels in driving current and future trends in atmospheric CO2 and the carbon cycle; (2) the capacities, limitations, and uncertainties of diverse options for deliberate carbon sequestration to offset emissions of anthropogenic CO2; (3) the importance of historical human carbon management in conditioning the current and future carbon-cycle response to anthropogenic CO2; and (4) the significance of changes in atmospheric CO2 and the carbon cycle in the geologic past.

Evaluating estimates of COemissions from power plants

The principal source of increasing atmospheric CO2 is the burning of fossil fuels.  In 2015, U.S. power plant emissions accounted for about 6% of global fossil fuel CO2 emissions.  Because of U.S. clean-air and fuel accounting requirements, these emissions are probably the most closely monitored globally significant source of anthropogenic CO2.  Dr. Sundquist’s team compiled an assessment of differences between the two datasets for CO2 emissions from all U.S. power plants.  The team quantified statistically significant differences in emissions estimates both for individual plants and for aggregated national totals.  This analysis revealed several potential sources of systematic bias, thereby identifying important sources of potential error in a globally significant CO2 flux.  Because U.S. power-plant emissions are monitored under optimal conditions, the work raises serious questions about uncertainties in the monitoring of CO2 emissions and carbon management activities throughout the world.

Understanding deliberate carbon sequestration and its context in the global carbon cycle

Many scientists and engineers are examining methods for deliberate carbon sequestration in plants, soils, the oceans, and geological repositories.  The Energy Independence and Security Act (EISA) of 2007 directed the Department of the Interior (DOI) and U.S. Geological Survey (USGS) to conduct comprehensive assessments of geologic and biologic carbon sequestration resources, including ecosystem greenhouse gas fluxes and underlying biogeochemical processes.  Dr. Sundquist has led efforts to foster interdisciplinary communication concerning carbon sequestration among researchers within the USGS and across the broader scientific community.   In 2005, he co-convened the American Geophysical Union (AGU) Chapman Conference on the Science and Technology of Carbon Sequestration, and he co-edited an AGU monograph based on papers presented at the meeting.  Dr. Sundquist also chaired the USGS Intedisciplinary Carbon Committee, which was formed to provide initial guidance for USGS comprehensive assessment of U.S. carbon sequestration resources.  Dr. Sundquist is currently developing new methods to quantify historical and potential future biological carbon storage in U.S. vegetation, wetlands, and soils.  This work provides a comprehensive carbon-cycle context for assessment of potential capacities, limitations, and uncertainties in both deliberate and natural biological carbon storage.

Quantifying effects of human land and water management on the carbon cycle.

Human needs for land and water resources – particularly for agriculture – drastically alter patterns of terrestrial carbon storage in soils, wetlands, and sediments.  Current estimates of the present-day terrestrial carbon “budget” do not adequately account for effects of soil and water management.  Similarly, estimates of potential future biological carbon storage do not include adequate assessment of the constraints imposed by changes in plants and soils under conditions of historical and ongoing land use.  Dr. Sundquist is leading an interdisciplinary effort to estimate effects of historical changes in erosion and sedimentation in the conterminous U.S.  This work has documented a significant historical transient of sediment eroded from soils and redistributed across the landscape due to past agricultural activities.  Using national datasets and models, the research is estimating effects of these historical changes on past and present-day carbon storage.  In addition to the importance of this work for quantifying carbon budgets and their uncertainties, it has broader implications for management of water and ecosystem resources that are affected by soil erosion and sediment deposition.

Discerning the importance of past changes in atmospheric CO2 and the carbon cycle.

The global carbon cycle and climate have varied together throughout Earth history.  Feedbacks inferred from the geologic record have profound implications for the response of climate to anthropogenic CO2, and for the potential response of the carbon cycle to changes in climate.  Dr. Sundquist’s work reflects a career-long interest in understanding the geologic history of the global carbon cycle.  In 1985 he edited the widely cited AGU Geophysical Monograph, The Carbon Cycle and Atmospheric CO2: Natural Variations Archean to Present.  He has been lead author of numerous articles on this topic, including the chapter, “The geologic history of the carbon cycle,” in the Treatise on Geochemistry.  Dr. Sundquist's approach emphasizes that the carbon cycle and climate are interactive components in a highly complex system of global feedbacks, in which atmospheric CO2 has been an important factor controlling climate, and climate has affected the carbon cycle and atmospheric CO2.  Dr. Sundquist is current working on research to understand the role of oceanic carbonate buffering in past geologic carbon-cycle changes.

Public service:

As a scientist and a public employee, Dr. Sundquist has devoted time throughout his career to activities that contribute to the public service mission of the USGS and to the communication of scientific information that is relevant to societal needs.

Within the USGS, Dr. Sundquist has served as Research Adviser for Surface Water Chemistry, he has chaired many peer review panels, and he has contributed to long-range and strategic planning for many USGS and DOI programs.  Dr. Sundquist is currently a member of the Program Council of the USGS Climate and Land Use Change Research and Development Program.

Dr. Sundquist has also served in national and international leadership positions outside the USGS.  He was a member of the National Academy of Sciences Panels on Sea Level Change (1984-1990), CO2 (1988-1992) and Oceanic Carbon (1992-1995); and he chaired the international Working Groups on Geologic Variations in CO2 and the Carbon Cycle (1985-1988) and Ocean/Atmosphere Paleochemistry (1988-1993) for the Scientific Committee on Oceanic Research of the International Council of Scientific Unions.  He was a co-author of the first U.S. Carbon Cycle Science Plan and the first North American Carbon Program (NACP) plan, and he is currently co-chair of the initiative to revise the NACP Implementation Plan.  He is a long-time member of the Advisory Board for the Community Earth System Model of the National Center for Atmospheric Research.

In 1997-1998, while serving on the AGU Committee on Global Environmental Change (CGEC), Dr. Sundquist proposed and co-authored the first AGU Position Statement on Climate Change and Greenhouse Gases.  As chair the AGU Focus Group on Global Environmental Change from 2000 to 2003, Dr. Sundquist led many activities to improve public understanding of climate change.  On numerous occasions, he took annual leave from his USGS position to visit Congressional and Federal program offices under AGU auspices to improve communications between the scientific and government communities.  Dr. Sundquist also served on panels to revise the AGU position statement on climate change in 2003 and 2012.

Throughout his career in public service, Dr. Sundquist has insisted on the independence and integrity of scientific information.  In 2000, as a member of the U.S. Carbon Cycle Scientific Steering Group, Dr. Sundquist initiated and was appointed lead scientist for the first U.S. State of the Carbon Cycle Report (SOCCR).  When Federal officials announced in 2004 that the report would be subject to final review and approval by political appointees, Dr. Sundquist withdrew from the report because he felt that he could not guarantee its scientific independence.  In 2009, Dr. Sundquist refused to accept the inclusion of policy prescriptions that had been added without his knowledge to a scientific presentation he had prepared for high-level Federal officials.  USGS management has consistently supported Dr. Sundquist's devotion to scientific independence and integrity.