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November 2022

CONTRIBUTING TO OSI’s CONSERVATION OF CLIMATE CRITICAL PENNSYLVANIA FORESTS: Our lab is proud to have contributed forest carbon analyses to support the Open Space Institute’s efforts to protect forests with their Appalachian Landscapes Protection Fund.  Their work is accelerating Pennsylvania land protection for carbon capture and wildlife protection within a 10 million acre focus area of western and central Pennsylvania, with a new $4 million expansion.  OSI’s announcement noted the following: “The Open Space Institute is proud of its role in harnessing land protection to secure the forests that are so critical to Pennsylvania and to us all,” said Peter Howell, OSI’s Executive Vice President of Conservation Capital & Research Programs. “Increasingly, science and higher resolution carbon data are highlighting just how important forests are in combatting climate change. OSI sincerely thanks the Richard King Mellon Foundation for its significant commitment, and Doris Duke Charitable Foundation whose early support helped to launch the Fund.”  Our forest carbon data are being used as the base layer as described in OSI’s guidelines document and resource list.

July 2022

NEW FUNDING to map climate protection from avoided deforestation: Dr. Williams received funding from the U.S. Climate Alliance to work with The Nature Conservancy’s Science Director for North America, Joe Fargione, to map opportunities to mitigate climate change with avoided deforestation in the U.S.. Williams’ team is providing detailed estimates of the carbon emissions that could be avoided by slowing or halting deforestation in the United States, along with high resolution maps of where forests are being lost and what they are being replaced by. This new work will significantly improve on prior estimates by using advanced techniques for mapping of forest losses, new assessment of deforestation emissions, detailed accounting of albedo offsets to mitigation, discounts associated with disturbance risks, and estimation of the costs of conserving forest for climate protection.

NEW STUDY on climate warming from albedo change with urbanization: A new study, published in Nature Communications, reveals global warming from albedo changes expected with future urbanization. The study relied heavily on the datasets and methods provided by Dr. Tong Jiao, PhD ’20, and Dr. Williams.

June 2022

CONSERVATION CARBON MAP of the Trust for Public Lands: The Trust for Public Lands recently released their new Conservation Carbon Map, including our team’s forest carbon storage and sequestration maps for the USA. Brendan Shane, Climate Director for TPL, writes that the Conservation Carbon Map is an innovative tool that helps users answer three key questions: (1) Where are existing forest carbon stocks and areas with high annual carbon sequestration rates? (2) What and where are the threats to these carbon-rich landscapes from development, insects and disease, and wildfire risk? AND (3) Where can climate conservation also provide multiple co-benefits by protecting drinking water supplies, rare ecosystems, and important habitat cores?

NEW STUDY on biophysical changes after severe wildfires in western US: A new study led by Geography PhD candidate, Surendra Shrestha, and published in Agricultural and Forest Meteorology, documents post-fire biophysical changes after severe wildfires in the US West. The paper, titled “Wildfire controls on land surface properties in mixed conifer and ponderosa pine forests of Sierra Nevada and Klamath mountains, Western US“, uses spaceborne remote sensing and geospatial analytics to create chronosequences of albedo, land surface temperature, LAI, and evapotranspiration, showing long-lasting legacies of ecological and biophysical change that are likely to impose significant land-atmosphere exchanges for decades after burning.

April 2022

ACADEMIC SYMPOSIUM on CLIMATE AND GLOBAL CHANGE RESEARCH AT CLARK: Dr. Williams joined a panel featuring Clark University’s high profile scholarly and engaged work on Climate and Global Change as part of the Inauguration Celebration for our new President, David B. Fithian ’87, our 10th President at Clark University. See Clark’s write up of this and other panel events here, or tune-in for a replay of the 1 hour session.

March 2022

NEW REPORT on forest clearing due to pellet mills in the southeastern US: Dr. Williams, with assistance from PhD student Li Xi, completed a study that analyzes satellite data of forest cover and forest biomass to map and quantify the effects of wood pellet mill operations on forest clearing and resource extraction rates in the southeastern US. The report, available here and titled “Forest Clearing Rates in the Sourcing Region for Enviva Pellet Mills in Virginia and North Carolina, U.S.A.“, was commissioned by the Southern Environmental Law Center and contributed to their associated press release.

February 2022

FOUR NEW STUDIES FROM ACT-AMERICA: PhD student Yu Zhou and Dr. Williams were involved in a suite of studies coming out of their participation in NASA’s ACT-America project. We have reported on others below but point to the following new additions including review of the mission and its findings by lead PI Ken Davis of Penn State University, overview of datasets from the campaign reported by Yaxing Wei of the ORNL DAAC, a study testing and advancing terrestrial biosphere models in the eastern US led by Sharon Gourdji of NOAA’s NIST, and a study evaluating CASA model carbon fluxes across North America with CO2 mole fraction and surface flux data, led by Sha Feng of Penn State University.

December 2021

Congratulations to Yu Zhou on successfully defending her dissertation and earning her doctorate!. Dr. Zhou will continue in research science with a postdoctoral position with Dr. Yiqi Luo at Northern Arizona University (now moved to Cornell University).

September 2021

NEW REPORT and MEDIA BRIEFING on “Avoided Deforestation: A Climate Mitigation Opportunity in New England and New York”:  Prof. Williams released a new report quantifying the climate mitigation that could be achieved by avoiding deforestation in seven states (NY, NH, ME, VT, CT, RI, MA) across the northeastern U.S.  This work emerged from a study funded through the U.S. Climate Alliance Natural and Working Lands Program by the Doris Duke Charitable Foundation and conducted in collaboration with The Nature Conservancy’s Dr. Laura Marx from the Massachusetts Chapter.   View the our media briefing to learn more, or check out the full report.  Or, visit The Nature Conservancy’s Resilient Land Mapper to fly through our dataset, zoom into your favorite region, and check out the contemporary carbon stocks and future sequestration opportunity all across the United States, displayed at a 30 meter resolution for over a billion pixels!  Or, see example media coverage by WBUR and WHDH.

July 2021

NEW STUDY – DETERMINANTS OF POST-DROUGHT VEGETATION RECOVERY: This study, from the dissertation of Dr. Tong Jiao and published in Global Change Biology, documents the conditions and factors controlling the rate of vegetation recovery after droughts, or the occurrence of persistent decline. The study is unique in its multi-sensor, multi-platform approach, its detailed diagnoses of time series, and its random forest approach to exposing determinants of post-drought recovery of Australia’s ecosystems during the Millennium Drought. We found that the probability of full recovery was most strongly controlled by drought return interval, post-drought hydrological condition, and drought length. The study sheds light on drought vulnerabilities and thresholds that should be helpful for modeling and prediction.

June 2021

NEW STUDY – Natural Climate Solutions for Canada: This study, led by Ronnie Drever of Nature United and published in Science Advances assesses the climate mitigation that can be achieved in Canada with nature-based solutions. With funding from The Nature Conservancy, the Williams Lab contributed to many of the study’s 24 NCS pathways, related to the protection, management, and restoration of natural systems, by analyzing the climate impacts of associated changes in surface albedo. This landmark research has made some headlines such as in the Globe and Mail. For more on Natural Climate Solutions visit here.

May 2021

INTERACTIVE WEB-MAPPING of our FOREST CARBON STOCKS AND FUTURE SEQUESTRATION from NFCMS – on TNC Resilient Land Mapping Tool: Our lab is proud to have our forest carbon stock and forest carbon sequestration datasets available for interactive navigation on the web made available by The Nature Conservancy’s Resilient Land Mapper. Fly through our dataset, zoom into your favorite region, and check out the contemporary carbon stocks and future sequestration opportunity all across the United States, displayed at a 30 meter resolution for over a billion pixels!

RELEASE OF THE NFCMS – National Forest Carbon Monitoring System: Our lab is proud to announce the release of our NFCMS dataset documenting forest carbon stocks and fluxes from 1990 to 2010 at a 30 m resolution for the conterminous United States. This emerges as part of our grant-funded work with the NASA Carbon Monitoring System scientific research program. The system integrates forest plot data from the USFS Forest Inventory and Analysis program with satellite remote sensing of biomass and of forest disturbances to initialize and guide a forest carbon cycle model to portray carbon stocks and fluxes for forest stands all across the country (over 1 billion pixels). The dataset is already being used intensively by a wide range of partners and practitioners, and is contributing new scientific understanding of forest carbon dynamics in a range of settings spanning protected lands where we see the value of conservation, areas of intensive harvest where we see the implications of biomass extraction and regrowth, locations with severe wildfires where we see post-fire recovery, and more.

NEW STUDY – Beyond Biomass to Carbon Fluxes in the Forest Sector: This study, led by PhD candidate Yu Zhou and including Williams lab members Dr. Natalia Hasler and former postdoc Dr. Huan Gu, reports on the application and evaluation of our comprehensive forest carbon monitoring system for the United States, the NFCMS (see above). With a detailed look across the Pacific Northwest (Oregon and Washington), we compare our biomass time series and spatial detail to other available data products and find remarkably reassuring agreement. We then apply the NFCMS to quantify net ecosystem productivity, harvest removals, net biome productivity, and net forest sector – atmosphere CO2 exchange for two and a half decades from the mid 1980s to 2010.

March 2021

NEW SCIENCE PLAN FOR THE NACP Led by Dr. Williams: The draft NACP Science Implementation Plan is a community-driven document that charts a course for the science of the North American Carbon Program over the next decade and beyond. Several years in the making, this initial draft is open for review and comment by NACP community members. Help shape the future of the NACP by providing comments here before the end of May. Additional details are presented in the Feb/Mar NACP newsletter, and in a presentation and panel led by Dr. Williams on March 19th as part of the 2021 NACP Open Science Meeting.

NEW FUNDING: The Williams Lab will be working with The Nature Conservancy on their large award from the Jeff Bezos Earth Fund. Clark’s team will be developing a global decision-support dataset and tool quantifying the albedo-related climate impacts of forests, to help guide efforts to cool the planet with reforestation and avoided deforestation.

February 2021

NEW STUDY – Climate Impacts of U.S. Deforestation Span Net Warming to Net Cooling: This study in Science Advances documents where forests in the U.S. cause a net cooling and where they contribute a net warming. We found that in some parts of the country like the Intermountain West, more forest actually leads to a hotter planet when we consider the full climate impacts from both carbon and albedo effects. If we fail to consider both the carbon and albedo effects, large-scale tree-planting initiatives could end up placing trees, or expanding forests, in locations that are counterproductive for cooling the climate system. It is all about putting the right trees in the right place and studies like this can help identify where we have the greatest biophysical potential for cooling the climate by adding forests or by slowing deforestation.

December 2020

Congratulations to Dr. Tong Jiao for successfully defending her dissertation and earning her doctoral degree in December.  Many thanks to her committee, including Dr.’s Rogan and Eastman from Clark University and Dr. Belinda Medlyn from the Hawkesbury Institute for the Environment at Western Sydney University. Dr. Jiao anticipates continuing in research science and data science with ESRI in California.

August 2020

NEW STUDY – Carbon budget of the Harvard Forest: Dr. Williams co-authored a comprehensive synthesis on the carbon balance of the Harvard Forest LTER, published in Ecological Monographs. From the Abstract: “How, where, and why carbon (C) moves into and out of an ecosystem through time are long‐standing questions in biogeochemistry. Here, we bring together hundreds of thousands of C‐cycle observations at the Harvard Forest in central Massachusetts, USA, a mid‐latitude landscape dominated by 80–120‐yr‐old closed‐canopy forests. These data answered four questions: (1) where and how much C is presently stored in dominant forest types; (2) what are current rates of C accrual and loss; (3) what biotic and abiotic factors contribute to variability in these rates; and (4) how has climate change affected the forest’s C cycle? Harvard Forest is an active C sink resulting from forest regrowth following land abandonment.” (full paper).

Mass Audubon Features Fast Facts about Forests from Prof. Williams Group: Our team’s work contributed to a fact sheet on ecosystem services features, including our estimates of forest carbon sequestration and forest carbon stocks across the state of Massachusetts. We estimate that 7% of MA’s annual carbon emissions are absorbed by the state’s 3 million acres of forest, with over 100 tons of carbon stored by the average acre. Additional fast facts, on water filtration, species conservation, wood products, flood protections, and more can be found here.

NASA Earth Data features our team’s surface biogenic CO2 exchanges simulated for North America, generated as part of the NASA ACT-America campaign. The featured zoom shows contrasting carbon source / sink patterns across pasturelands and croplands from Oklahoma to Tennessee. Earth Data are available at the ORNL DAAC here.

March 2020

Congratulations to PhD student Li Xi on receiving an Edna Bailey Sussman Fellowship Award. The project will involve collaboration with Laura Marx of The Nature Conservancy – Massachusetts Chapter who will assist us with developing the science and communications around forest conversion maps for the Northeastern US and associated carbon emissions and lost carbon uptake.

January 2020

NEW STUDY – Vegetation Decline from Water Shortages during the Millennium Drought in Australia. PhD student Tong Jiao published a new paper in JGR – Biogeosciences documenting the decline of vegetation in Australia ensuing throughout the MD. The study relies on a suite of satellite sensors across multiple platforms to analyze ecosystem responses and to assess their differential sensitivity to drought across the continent.

November 2019

Congratulations to Dr. Williams on receiving a new award from the US Climate Alliance in collaboration with Dr. Laura Marx of The Nature Conservancy – Massachusetts Chapter. The team will develop detailed, geospatially-explicit mapping of forest conversion across New England plus New York, and also the associated carbon emissions and lost carbon uptake. In addition, the team will tailor the delivery of these findings for use by partner states across the region for state-level inventory reporting and also to provide information critical to assessing opportunities for mitigating climate change by curbing deforestation.

September 2019

Welcome to incoming PhD student Li Xi and congratulations on being awarded Clark’s Libbey Fellowship in Earth System Science. Li joins us from Binghamton University (SUNY) where she earned a B.A. and M.A. in Geography. She brings expertise in detecting and monitoring land cover change with big data geospatial analytics of medium resolution satellite imagery (Landsat data).

August 2019

NEW STUDY – Carbon Balance of the Southeastern US Forest Sector. The Williams Lab published a new paper in JGR – Biogeosciences documenting the annual carbon stocks and fluxes from 1986 to 2010 at 30‐m resolution across southeastern U.S. forests, analyzing trends and regional greenhouse gas exchange. We found that net biome productivity exhibited large interannual variability, spanning a sink of 16 Tg C/year in 1986 to a source of −30 Tg C/year in the year of peak harvest. Also, two thirds of harvest removals are emitted within 50 years, with 8% as methane, causing the forest sector to act as a large CO2‐equivalent source.

January 2019

SABBATICAL for Dr. Williams at ETH – Zurich: Dr. Williams enjoyed being in residence at ETH-Zurich for a 7 month sabbatical stay with Professor Dr. Nina Buchmann (Grassland Sciences Group) and Professor Dr. Sonia Seneviratne (Atmospheric and Climate Science Group) at the Department of Environmental Systems Science (D-USYS). 

NEWS FEATURE in Nature: Dr. Williams’s work is featured in a news story in Nature titled “How much can forests fight climate change?”  The news feature, authored by Gabriel Popkin, explains that while trees are supposed to slow global warming, growing evidence suggests they might not always be climate saviours.  An excerpt from the article notes: “Researchers are now turning to sophisticated computer models and using larger and more-comprehensive data sets to nail down exactly what forests in different places do to the climate. In some cases, the results have been sobering. … To estimate the climate impact of planting forests in different parts of the United States, ecologist Christopher Williams at Clark University in Worcester, Massachusetts, is combining global satellite data collected over more than a decade with carbon-sequestration figures based on data from the US Forest Service. He has found in preliminary work that adding trees to the US west coast and to regions east of the Mississippi River makes sense, climatically speaking. But albedo changes make forest planting in the Rockies and the southwestern United States a bad deal for the climate in most cases, because the conifers that thrive in those regions are dark and absorb more sunlight than do underlying soils or snow. He hopes to turn this research into a standardized methodology that forest managers can use to assess a project’s climate impact.”

December 2018

AGU: Several Members of BRG attended the American Geophysical Union Annual Meeting held in Washington, DC, delivering presentations of the work led by Dr.’s Williams and Gu, and PhD candidates Tong Jiao and Yu Zhou.

November 2018

NEW REPORT: Dr. Williams is co-lead on the Forests chapter of a comprehensive US Global Change Research Program report entitled Second State of the Carbon Cycle Report (SOCCR2): A Sustained Assessment Report.  The effort involved over 3 years of work, over 200 scientists, with extensive reviews and revisions.  It provides a detailed and thorough review of the state of understanding of North America’s carbon cycle, its trends, its drivers, and its future along with possible management opportunities to serve society (full report).

NEW STUDY: Dr. Williams and Dr. Gu involved in a new study published in Science Advances (link): Natural Climate Solutions for the United States documents opportunities for land stewardship that can contribute to limiting global warming through reducing land-based emissions and enhancing land-based carbon storage.  The Clark University team contributed the Avoiding Forest Conversion pathway, quantifying how much forest is lost annually across the United States, and the amount of carbon dioxide that emits to the atmosphere. Check out how much your state can contribute. Also, read more in the following Clark Now feature

October 2018

The BRG had a great showing at the international ForestSAT conference held in College Park, MD, delivering presentations of the work led by Dr.’s Williams and Gu, and PhD candidates Tong Jiao and Yu Zhou.

Yu Zhou enjoyed attending the Ecological Society of America annual meeting in August 2018, in New Orleans, LA. Yu presented in the Inspire session “Improving the Predictive Ability of the Global Carbon Cycle Models”.

July 2018

Dr. Williams joined leaders of state and federal governments and environmental organizations for the Climate Alliance Learning Lab on Natural and Working Lands initiative.  Held in Washington, DC, the group examined priority opportunities for environmental management and policy actions that could be taken by 17 US states committed to the alliance to work toward meeting international climate change mitigation goals and commitments. To learn more, see:

June 2018

Dr. Williams was one of two U.S. scientists to participate in a science workshop and science-policy dialogue hosted by the International Boreal Forest Research Association.  The meeting, in Haparanda, Sweden, was held in conjunction with the 2018 Boreal Summit involving ministers from the USA, Canada, Sweden, Norway, Finland, Denmark, and Russia.  The workshop identified key boreal science issues related to the use of boreal forests for climate change mitigation and adaptation, and to foster the development of circumboreal collaborations that will address these knowledge gaps.

May 2018

Congratulations to Surendra Shrestha on securing a Sussman Fellowship supporting a summer in residence at the National Center for Atmospheric Research (NCAR) in Boulder, CO.  Surendra worked within the group of Dr. Gordon Bonan to learn the Community Earth System Model (CESM) with the goal of developing innovations to the global climate model framework that will enable us to explore the climate and water resource impacts of forest disturbances, including harvesting, wildfires, and beetle outbreaks. 

Congratulations to Yu Zhou on successfully completing qualifying exams and dissertation proposal stages of her PhD pursuit.

April 2018

Congrats to Yu Zhou for being selected to attend a May short course on New Advances in Land Carbon Cycle Modeling hosted by Yiqi Luo’s EcoLab of the Center for Ecosystem Science and Society at Northern Arizona University.

December 2017

A Busy AGU Fall Meeting: Our group presented several papers, hosted a session and side meetings for the NACP Science Implementation Plan, and joined the ACT-America Project Meeting.

October 2017

Great meetings lately, including the 10th International Carbon Dioxide Conference in August 2017, Interlaken, Switzerland and the FIA Science Meeting in October 2017, Park City, UT, where Dr. Williams presented an invited talk.

September 2017

Welcome to incoming PhD student Surendra Shrestha and congratulations on being awarded Clark’s Libbey Fellowship in Earth System Science. Surendra joins us from University of Georgia’s M.S. program in Forest Resources. He brings expertise in hydrologic and land-atmosphere impacts of land cover and use change.

July 2017

Dr. Williams Joins the NACP Science Leadership Group, nominated by members of the Carbon Cycle Science Interagency Working Group. Williams has also been appointed to serve as a co-Chair of the NACP Science Implementation Plan. For more information see the Clark News Announcement.

May 2017

Congratulations! Tong Jiao has just been Awarded a NASA Earth Science Fellowship to fund her Ph.D. research documenting impacts of the Millennium Drought in Australia with a widespread suite of remote sensing observations.

Prof. Williams joined the March for Science – Boston: See his personal statement about why.

April 2017

Congratulations to Savannah Cooley for being awarded an Edna Bailey Sussman Fellowship to support her summer research at NASA JPL in Pasadena, CA! Ms. Cooley will continue her work exploring applications of ECOSTRESS data to support decisions about water use and management in landscapes with irrigated agriculture with a focus on the Guanacaste Province of Costa Rica along with partners from Earth University.

Congratulations to Yu Zhou for being awarded an Edna Bailey Sussman Fellowship to support her summer research at the Harvard Forest LTER! Ms. Zhou will (1) participate in field measurement programs recording biomass in recently harvested landscapes, and (2) use time series of plot-measured biomass to constrain a biogeochemical model for estimating rates of carbon uptake and release.

November 2016

Dr. Williams Co-Authors Paper in Nature Communications. The research paper, published with open access here and highlighted by Clark here, and BBCNews, documents how terrestrial ecosystem uptake of atmospheric CO2 has risen in recent decades, largely due to enhanced productivity likely caused by elevated CO2 concentrations, and also how the past decade or so has seen a pause in the growth rate of atmospheric CO2 partly because of a relatively modest rate of warming over land and a corresponding slow down in the rate of ecosystem respiration.

September 2016

The Data-Driven and Simulation Science Summer School in Jena hosted by Friedrich Schiller University and the Max Planck Institute for Biogeochemistry will be attended by doctoral student Yu Zhou in September 2016.

Dr. Williams Co-Authors Paper in Nature Climate Change. The research, highlighted by Clark here, documents how dry air can stress plants just as much as dry soils, and how this source of stress is becoming increasingly severe as the planet warms.

Congratulations to Dr. Williams on receiving a new award from the NASA CMS Program. The project, led by Dr. Robert Kennedy of Oregon State University, funds research to develop and apply new tools to quantify and characterize the carbon impacts of forest disturbances with remote sensing analyses combined with modeling frameworks.

Congratulations to Yu Zhou for a Travel Award to attend the Data-Driven and Simulation Science Summer School in Jena being hosted by Friedrich Schiller University and the Max Planck Institute for Biogeochemistry.

June 2016

Dr. Williams’s Sabbatical Research is Featured by Clark University. The highlight, available here, features a conversational introduction to Prof. Williams’s work on vegetation stress and dieback in response to droughts and heat contrasted with enhanced plant growth stimulated by rising concentrations of carbon dioxide.

May 2016

Congratulations to Dr. Williams on receiving a new award to join the NASA ACT-America project. NASA ACT-America is an Earth Ventures Suborbital 2 activity being led by Science PI Ken Davis of Penn State University. Dr. Williams’s team will assist with estimating spatially-explicit, time-varying fluxes of carbon dioxide between the surface and atmosphere.

September 2015

Welcome to incoming PhD student Yu Zhou and congratulations on being awarded Clark’s Libbey Fellowship in Earth System Science. Yu joins us from the Chinese Academy of Sciences M.S. program in Remote Sensing and Digital Earth in Beijing. She brings expertise with remote sensing of ecosystem water and carbon cycles and their linkages to climate with a recent thesis titled “Analysis of spatial and temporal patterns of water use efficiency (WUE) in Central Asia”.

Sabbatical begins for Prof. Williams at the Hawkesbury Institute for the Environment of UWS in Australia where he will be examining detailed mechanisms of ecosystem functional and structural responses to drought and seeking to incorporate these dynamics in ecosystem process models along with his sabbatical hosts, Dr. Belinda Medlyn (lab group) and Dr. Remko Duursma.

Congratulations to Prof. Williams for being awarded Clark University’s Oliver and Dorothy Hayden Junior Faculty Fellowship for excellence in teaching, excellence in scholarship, and deep and sustained engagement with the Clark community.

May 2015

Clark Convenes a Climate Change Teach-In — Dr. Williams Delivers Plenary Lecture: Video is available on the teach-in website, with Williams’s fourth from the top titled “The Truth About Climate Change and a Pathway to a Safer Future“.

February 2015

Welcome to Dr. Huan Gu who recently joined the group to work on our NASA Carbon Monitoring System project.

Dr. Williams presented in the Yale School of Forestry Lunch Forum of the Global Institute of Sustainable Forestry.

December 2014

MacLean and Williams are off to the American Geophysical Union Fall Meeting in San Francisco to present their work.  Come see us if you have a chance!

November 2014

Congratulations to Alex Kappel for successfully defending his M.S. thesis titled “Mapping of the Asian Longhorned Beetle’s Time to Maturity and Risk to Invasion across the Contiguous United States“, and earning his M.S. in Geographic Information Science.  We thank Dr. Robert (Talbot) Trotter III, Research Ecologist at the USDA Forest Service, for serving as a committee member bringing us expert advice and for providing excellent mentorship.  Alex is currently employed AidData based at William & Mary.

October 2014

A Recent Perspective by Dr. Williams Explores How Heatwaves and Drought Are Likely to Stress Ecosystems Even More in a Warmer, CO2 Rich Future, solicited by Environmental Research Letters as a response to a recent paper by Ian Williams and colleagues at the Lawrence Berkeley National Lab. web copy

September 2014

Welcome to incoming PhD student Tong Jiao and congratulations on being awarded Clark’s Libbey Fellowship in Earth System Science. Tong joins us from Beijing Forestry University with expertise in remote sensing of forests and biogeosciences of terrestrial ecosystems, one of 11 new members of the Geography PhD program in Fall 2014.

New Grant Funding from NASA’s Carbon Monitoring System: Congratulations to Dr. Williams for securing funding from NASA’s Carbon Monitoring System for a proposal entitled “Translating Forest Change to Carbon Emissions/Removals Linking Disturbance Products, Biomass Maps, and Carbon Cycle Modeling in a Comprehensive Carbon Monitoring Framework“. The project involves close collaboration with Co-Is Dr. G. James Collatz and Dr. Jeff Masek of NASA GSFC and Dr. Gretchen Moisen of the US Forest Service Forest Inventory and Analysis Program. See an associated Clark News Hub announcement.

July 2014

Congratulations to Dr. Melanie Vanderhoof for successfully defending her dissertation and earning her doctoral degree in July.  Many thanks to her committee, including Dr.’s Rogan and Kulakowski from Clark University and Dr. Jeffrey Masek of NASA GSFC.

Tenure for Prof. Williams: Congratulations to Dr. Williams for earning tenure and being promoted to the level of Associate Professor effective September 2014.

May 2014

Reviewing Excellence Award for Prof. Williams: Congratulations to Dr. Williams for receiving the “Excellence in Reviewing” award for 2013 from Journal of Geophysical Research – Biogeosciences.

April 2014

Congratulations to  Rich MacLean, who received an award from the Edna Bailey Sussman Foundation to support summer research on the climate impacts of forest management with study at Harvard Forest.

NASA Carbon Cycle Science awarded Co-I Williams support for a project titled “Quantification of the regional impact of terrestrial processes on the carbon cycle using atmospheric inversions” being led by PI Ken Davis of Penn State University.

Prof. Williams accepted an invitation to join as Editor of Biogeosciences.

Reviewing Excellence Award for Prof. Williams: Congratulations to Dr. Williams for receiving the “Excellence in Reviewing” award for 2013 from Biogeochemistry.

December 2013

Melanie Vanderhoof (Ph.D. candidate) recently published two research papers on albedo impacts of bark beetle outbreaks recently published in JGR-Biogeosciences (pdf copy) and Biogeosciences (web copy), both of which were also presented at the recent AGU Fall Meeting.  (See updated pdf copies on the publications page)

Congratulations to undergraduate student Rebecca Walker (Harvard Forest REU ’13, UVA BA ’14) for her excellent poster presentation delivered at the recent Fall Meeting of the American Geophysical Union.

Albedo and Land Change Meeting Hosted: Dr. Williams hosted a group of leading remote sensing scientists for a team meeting to conclude a three-year, NASA-funded study on “Albedo Trends Related to Land Cover Change and Disturbance: A Multi-sensor Approach”. (see the write-up at Clark’s News Hub)

October 2013

Post-Clearcut Research Paper published: see highlights and photos plus press resources covering our recent publication documenting carbon, water, and energy exchanges following forest clearing at Harvard Forest, authored by Prof. Williams’s Lab, (web copy). Also see the Clark University News Release.

August 2013

Congratulations to Prof. Williams for receiving the 2013 Hodgkins Junior Faculty Award from Clark University. This award is given to an un-tenured junior faculty member to promote and recognize outstanding research and teaching successes.

Congratulations to Dr. Prajjwal Panday on his paper “Application and evaluation of a snowmelt runoff model in the Tamor River basin, eastern Himalaya using a Markov Chain Monte Carlo (MCMC) data assimilation approach” recently accepted in Hydrological Processes. After earning his doctorate from the Graduate School of Geography at Clark University in May of 2013, Dr. Panday joined the Woods Hole Research Center to advance ecological modeling of vegetation dynamics in the Amazon.

Thanks to Rebecca Walker (Univ. of Virginia ’14) and Lowell Chamberlain (SUNY ESF ’14) for their excellent work during the 2013 REU program at the Harvard Forest LTER. In addition to collecting data supporting our core research at the clearcut site, Rebecca analyzed vegetation transect data to study early successional species interactions and Lowell examined possible determinants of relative abundance for various species following recent clearing. You can read more about their experience in a 2013 Undergraduate Research Blog. Congratulations to both!

May 2013

Congratulations to Alex Kappel for earning High Honors on his thesis entitled “Post Disturbance Soil Respiration Dynamics in a Clear Cut Temperate Forest”. Congratulations also on earning your Bachelor’s in Environmental Science with the Earth System Science Track.

Congratulations to Thor Akerley for his excellent research presentation entitled “Quantifying Species-Specific Differences in Leaf Area—Leaf Mass Relations in a Regenerating Temperate Forest”, and for earning his Bachelor’s in Environmental Science with the Earth System Science Track.

Prof. Christopher A. Williams was involved in a live radio broadcast of Locus Focus (KBOO-FM out of Portland, OR) where he discussed the current severe drought conditions being experienced throughout many parts of North America in the context of historic droughts, and the role that climate change is playing in the intensification of extreme weather events.

December 2012

Prof. Williams participated in a NASA Press Briefing reporting recent trends in wildland fires, their link to climate change now and into the future, and the associated carbon emissions feedback to climate change (Clark Coverage). Dr. Bardan Ghimire is the lead author of the corresponding publication (see Publications, 2012 JGR-B). This news ran in a numerous outlets including ScienceNewsline, Science Codex,, Bloggera Science News, Science Daily, TheStreet, and many local newspapers and online blogs (full press briefing). You can also see Prof. Williams’s related invited talk.

Congratulations to Dr. Bardan Ghimire for being selected as one of the early career scientists sponsored to attend the upcoming RCN FORECAST meeting focused on model-data fusion techniques in biogeosciences.

Congratulations to Bardan Ghimire, Ph.D. for earning his doctorate from the Graduate School of Geography at Clark University with a dissertation entitled, “Biogeochemical and Biophysical Consequences of Disturbances in Forests of the Western United States”.

August 2012

Prof. Williams’ research on droughts in the American West received significant press, including an Opinion piece in the NYTimes, an interview with Tom Ashbrook on NPR’s On-Point, and a blog posting in the NYTime’s Dot Earth Blog maintained by Andrew Revkin. This work also initiated a local TV news spotlight with New England Cable News.

Dr.’s Christopher Schwalm (NAU, formerly Clark), Prof. Williams (Clark), Dr. Kevin Schaefer (NSIDC) and others just published in Nature-Geoscience a paper documenting the carbon, water, and crop impacts of the severe 5-year drought striking western North America at the turn of the century (2000-2004). Carbon uptake declined by around 50% during the drought. The study also showed how projected changes in rainfall and drought severity foretell a coming megadrought-like condition in the late 21st century, likely causing the present-day carbon sink in western North America to disappear by the end of the century as well as bringing a host of additional water resource challenges to a region already accustomed to frequent water stress. Clark University press release.

Congratulations to Melanie Vanderhoof (Clark PhD student) and Marcus Pasay (Clark ’12, pursuing MS ’13) on a successful field season in Colorado exploring biophysical impacts of bark beetle outbreaks.

Welcome to incoming PhD student Rich MacLean and congratulations on being awarded Clark’s Libbey Fellowship in Earth System Science. Rich joins us from the University of New Hampshire and arives with expertise in forestry and ecosystem biogeochemistry, one of 8 new members of the Geography PhD program starting in Fall 2012.

June 2012

A recent publication by Prof. Williams, featured in Water Resources Research and the AGU weekly newspaper Eos, documents how vegetation and climate types influence water resource availability by regulating the amount of water that runs into rivers compared to how much is lost to the atmosphere through evaporation.

See the Undergraduate Research Profile featuring Alex Kappel (Clark ’13) and Paul Quackenbush (Middlebury ’14) immersed in field research at Harvard Forest as part of the LTER Research Experience for Undergraduates (REU) program.

Congratulations to Melanie Vanderhoof for winning a student presentation competition at the recent AMS 30th Agricultural and Forest Meteorology/First Atmospheric Biogeosciences Conference.

May 2012

Welcome to Dr. Myroslava Khomik, the group’s new postdoctoral researcher arriving from the Max-Planck Institute for Biogeochemistry in Jena, Germany. She will officially start at Clark in September 2012, but is visiting in May and July-August to assist with field research activities. Dr. Khomik examines nutrient, water and carbon flows in forests with expertise centering on the measurement and modeling of plant physiology and soil organic matter decomposition in mature and afforested environments.

Undergraduates Alexander Kappel (Clark ’13) and Paul Quackenbush (Middlebury ’14) have been selected to participate in our 2012 field research at Harvard Forest as part of the LTER Research Experience for Undergraduates (REU) program with the mentorship of Melanie Vanderhoof (Clark PhD student), former REU Marcus Pasay (Clark ’12, pursuing MS ’13), and Prof. Williams.

December 2011

Congratulations to Christopher Schwalm (former Postdoc) for securing a Research Assistant Professor position at Northern Arizona University.

Prof. Williams enjoyed a refreshing Fall 2011 sabbatical as a Visiting Professor at the Swiss Federal Institute of Technology, Lausanne (EPFL) within the ecohydrology and environmental fluid mechanics group of Prof. Marc Parlange (

June 2011

Congratulations to Melanie Vanderhoof (PhD student, Geog.) for receiving a NASA Earth and Space Science Fellowship to support her doctoral research (PI Williams).  Her proposal is titled “Albedo and Evapotranspiration Consequences of Bark Beetle Outbreaks as Detected by Remote Sensing in Coniferous Forests, Rocky Mountains, USA”.

Undergraduates Marcus Pasay (Clark ’12) and Katharine Chute (Harvard ’11) have begun their summer of field research at Harvard Forest as part of the LTER Research Experience for Undergraduates (REU) program with the mentorship of Melanie Vanderhoof (Clark PhD student), former REU Angie Marshall (Clark ’11), and Prof. Williams.

May 2011

Congrats and good luck to Graham Twibell (Clark ’10 BA, ’11 MA) as he begins work with the Cary Institute of Ecosystem Studies, Millbrook, NY.

Good luck to Krittika Govil (Clark ’11) as she continues her studies to work toward a Masters in hydrology at Texas A&M.

Congratulations to Angela Marshall (Clark ’11) for receiving the NCGE Excellence in Scholarship Award at graduation.

February 2011

Prof. Christopher Williams has been funded by NASA The Science of Terra and Aqua as a Co-PI on a three-year, $866,082 project examining remotely sensed albedo trends related to land cover change and disturbances.

Melanie Vanderhoof (PhD Geog. student) has received a Geller Endowment Research Award, administered by Clark’s George Perkins Marsh Institute, for her proposal “Woody debris decomposition dynamics in a post-harvest chronosequence”.

Angie Marshall (Clark ’11 Honors) presented a poster at the Massachusetts Climate Action Network hosted at Clark University. The presentation was titled, “Harvest-induced elevation of coarse and fine woody debris imposes a legacy of carbon emissions: Comparison to pre-harvest and undisturbed forest”.

October 2010

Prof. Christopher Williams has been funded by the NASA Terrestrial Ecology Program for a three-year, $655,000 project on carbon consequences of forest disturbances.

Prof. Christopher Williams is the co-author of a recent report in Nature, “the leading weekly international science journal” 13 October 2010, Recent decline in the global land evapotranspiration trend due to limited moisture supply.

July 2010

Prof. Christopher Williams co-authored a report in Science, the journal of the American Association for the Advancement of Science and the “world’s leading journal of original scientific research, global news, and commentary.” 7/5/2010 Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate.

Undergraduates Angie Marshall (Clark ’11) and Crystal Garcia (Baylor Univ ’11) completed a successful summer of field research at Harvard Forest as part of the LTER Research Experience for Undergraduates (REU) program.

Bardan Ghimire (PhD Geog. candidate) was funded by a NASA Summer Fellowship to explore “Biogeochemical and Biogeophysical Consequences of Forest Disturbances across the Conterminous U.S.”

Melanie Vanderhoof (PhD Geog. candidate) was awarded Clark’s Libbey Fellowship in Earth System Science. She joined the Geography PhD program in Fall 2010.

January 2010

Prof. Christopher Williams has been invited to serve as an Associate Editor of Biogeochemistry, a highly-ranked international journal publishing original papers on ecosystem carbon and nutrient cycles. With his new position, Prof. Williams has been asked to help raise the journal’s profile with regards to plant and ecosystem carbon cycle science.

August 2009

Clark Undergraduates Graham Twibell (Clark ’10) and Michelle Smith (Clark ’11) completed a successful summer of field research having been selected for NSF REU supplement award supporting Prof. Williams’ NSF grant.