2023
December
Get ready for AGU2023!
We host an oral session on Friday from 16:00 - 17:30 PST in 2006 - West (Level 2, West, MC) GC54B - Bridging Science and Policy for Effective Climate Mitigation and Sustainable Carbon Neutrality II Oral. The poster session is from 8:30 - 12:50 PST on Friday at Poster Hall A-C - South (Exhibition Level, South, MC).
My collaborators and I have several presentations:
Zhou et al. B43H-2646 Convergent Pattern of Plant Strategies in Varied Dryness Conditions. December 14, 14:10 - 18:30 PST, Poster Hall A-C - South (Exhibition Level, South, MC).
Chandel et al. B43G-2634 Investigating the Role of Hydraulic Redistribution on Water and Carbon Cycle in Dryland Ecosystems: Empirical and Modeling Approaches. December 14, 14:10 - 18:30 PST, Poster Hall A-C - South (Exhibition Level, South, MC).
Luo et al. GC54B-09 Preserving wood debris towards net-zero carbon emission. December 15, 17:12 - 17:21 PST, 2006 - West (Level 2, West, MC).
Zhou et al. B44A-05 Interactive effect of elevated CO2 and warming on the carbon cycle in a boreal peatland. December 14, 16:44 - 16:55 PST, 3008 - West (Level 3, West, MC).
Wang et al. H13J-1574 Trait mechanisms of plant community response and adaptation to drought in arid-semi-arid grassland of Northern China. December 11, 14:10 - 18:30 PST, Poster Hall A-C - South (Exhibition Level, South, MC).
Ruehr et al. GC21H-1009 Attribution and evidence for historic enhancement of the land carbon sink. December 12, 08:30 - 12:50 PST, Poster Hall A-C - South (Exhibition Level, South, MC).
Dong et al. Intensive Land-use Led to Trade-offs of Sustainable Development Goals in Port Cities of Southeast Asia. 24 January 2024, 08:00 - 09:30 PST, GC07 - Online Poster Session for Global Environmental Change: Urban XV.
July
Call for abstract! Working on Carbon Dioxide Removal? Developing innovative approaches? Evaluating current CDRs for broader application? 🧐 Submit your work to #AGU2023 Session GC063 - Leveraging Multifaceted Approaches to Carbon Dioxide Removal for Effective Climate Change Mitigation! 🌎🌍🌏https://agu.confex.com/agu/fm23/prelim.cgi/Session/185033
Thrilled to share our new paper in Nature Reviews Earth & Environment! Here we look into the past to help the future. Evidence and attribution of the enhanced land carbon sink 🌳🌧️⛅️.
How to manipulate both the mean and variance of precipitation? Check out our paper about the Sevelliate experiments on the dryland ecosystems in Ecosphere: Infrastructure to factorially manipulate the mean and variance of precipitation in the field. 🌧️
June
Glad to be the instructor of the 6th training course on New Advances in Land Carbon Cycle Modeling. We will have Hybrid Virtual + in Person this year! Check out more details about this course https://ecolab.cals.cornell.edu/?workshop.
March
Our new results about how land-use is associated with development status in port cities are online on Environmental Research Letters now! Check out why these cities are important, how they have evolved in the past decades, and what they are expected to experience in the next several decades!
February
Check out how we pinned down the sources of across-model spread! This work is available on Global Change Biology now! Thanks to Dr. Enqing Hou for leading this work!
January
Our group attended SEV all-hands meeting in Albuquerque, presented ModEx results, and visited the nice field experiment sites!
I am thrilled to join the first cohort of the Eric and Wendy Schmidt AI in Science at Cornell University! Check out this website to explore 2023 postdoc fellowship openings!
2022
December
AGU presentations:
Improved Estimates of Carbon and Water Dynamics by TECO-Dryland and Data Assimilation. Yu Zhou (presenting author).
The Biogeochemical Model Database bgc_md2, a Python Package for Fast Comparison and Benchmarking of Element Cycling Models. Markus Müller (presenting author).
Towards reducing uncertainty in land carbon predictions through the Global Matrix MIP traceability framework. Kostiantyn Viatkin (presenting author).
How can we use comprehensive ensembles to improve regional carbon flux estimation? Sha Feng (presenting author).
August
Moved to Ithaca and started my new position as a Postdoctoral Associate at Cornell University!
May
I will be the instructor of the 5th training course on New Advances in Land Carbon Cycle Modeling. We will have Hybrid Virtual + in Person this year! Check out more details about this course https://www2.nau.edu/luo-lab/?workshop.
2021
November
Check out our new paper led by Dr. Sharon Gourdji. This work introduces a modified Vegetation Photosynthesis and Respiration Model that is relatively unbiased and better explains hourly atmospheric CO2 variability compared to other biospheric models. It's available on JRG-Biogeosciences now!
August-September
Moved to Flagstaff and I am ready to start my postdoc at Northern Arizona University!
July
Back in Worcester!
June
Our NFCMS dataset is available now! Check out https://doi.org/10.3334/ORNLDAAC/1829. It provides estimates of forest carbon stocks and fluxes in the form of aboveground woody biomass (AGB), total live biomass, total ecosystem carbon, aboveground coarse woody debris (CWD), and net ecosystem productivity (NEP) as a function of the number of years since the most recent disturbance (i.e., stand age) for forests of the conterminous U.S. at a 30 m resolution for the benchmark years 1990, 2000, and 2010. Have fun exploring it!
March
Our paper 'Beyond biomass to carbon fluxes: application and evaluation of a comprehensive Forest Carbon Monitoring System' is accepted by Environmental Research Letters!
2020
December
We have two presentations at the AGU fall meeting this year. Check this out!
Abstract ID# 743618: Matrix MIP to trace uncertainty in predicting land carbon dynamics lead by Enqing Hou from NAU.
Abstract ID# 740452: Constraint of terrestrial model parameters from ensemble forward simulations lead by Sha Feng from PSU.
Our dataset 'Ensemble model output of North American atmospheric CO2 simulations for summer 2016, including transport, CASA and CT2017, and boundary condition ensembles' is available on Penn State Data Commons now! The resulting “super ensemble” of modeled [CO2] demonstrates that the biosphere introduces the majority of uncertainty to the simulations and that biogenic [CO2] can be lifted by the fronts beyond the top of the atmospheric boundary layer.
November
Our paper 'Species diversity with comprehensive annotations of wood-inhabiting poroid and corticioid fungi in Uzbekistan' is accepted by Front. Microbiol. - Fungi and Their Interactions! I really enjoyed my collabration with the fungi group! (pdf copy)
August
Welcome back to another year at Hogwarts Clark!
July
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. Data are available at the ORNL DAAC. More on ACT-American be found at https://www-air.larc.nasa.gov/missions/ACT-America/index.html.
February
Our paper 'A Multiyear Gridded Data Ensemble of Surface Biogenic Carbon Fluxes for North America: Evaluation and Analysis of Results' is online in JGR-Biogeosciences. The dataset is available on ORNL DAAC https://doi.org/10.3334/ORNLDAAC/1675. (pdf copy)
January
Our paper 'Increased carbon uptake and water use efficiency in global semi-arid ecosystems' is online in Environmental Research Letter. (pdf copy)
Happy new year and welcome to the 2020s!
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2019
December
Our paper 'Seasonal characteristics of model uncertainties from biogenic fluxes, transport, and large‐scale boundary inflow in atmospheric CO2 simulations over North America' is online in JGR-Atmospheres. (pdf copy)
I will attend the 2019AGU fall meeting at San Fransisco, CA.
I will present our recent work: Linking Biomass Data with Carbon Cycle Modeling in Session B13H - Complexity and Emergent Behavior in the Terrestrial Carbon Sink II Posters.
Dr. Williams will present Carbon, Climate, and US Forests: Synthesis of Harvesting, Wood Products, Deforestation, Reforestation, and Natural Disturbance Impacts in Session B027 - Carbon Monitoring Systems Research and Applications.
August
Our paper 'The Carbon Balance of the Southeastern U.S. Forest Sector as Driven by Recent Disturbance Trends' is online in JGR - Biogeosciences! This study documents 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. Find the data here https://doi.org/10.3334/ORNLDAAC/1728! (pdf copy)
April
Our paper 'Improved simulation of carbon and water fluxes by assimilating multi-layer soil temperature and moisture into process-based biogeochemical model' is online in Forest Ecosystems. This study improves the estimations of soil-related processes in Biome-BGC MuSo by assimilating ground-measured multi-layer daily soil temperature and moisture at the Changbai Mountains forest flux site by using the Ensemble Kalman Filter algorithm. (pdf copy)
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2018
December
Our paper 'Spatiotemporal transition of institutional and socioeconomic impacts on vegetation productivity in Central Asia over last three decades' is available online in Science of The Total Environment! The findings highlight the spatiotemporal changes of institutional and socioeconomic impacts on vegetation productivity in Central Asian dryland and provide implications for future dryland management and restoration efforts. (pdf copy)
I will attend the 2018 AGU fall meeting in DC, Washington.
I will present our recent work: A multi-year gridded data product of surface biogenic carbon fluxes for North America: Evaluation and analysis of results, Y Zhou, CA Williams, T Lauvaux, S Feng, K Keller, KJ Davis in the Session B41J: Advances in Uncertainty Assessment and Reduction for Terrestrial Carbon Cycle Diagnosis and Prediction II Posters, Location: Convention Center; Hall A-C (Poster Hall). Look forward to seeing you there!
Dr. Williams will present: Moving Ecosystem Carbon Cycle Models Forward: Strategies for Improved Assessment and Prediction, Christopher A Williams, Yu Zhou, Huan Gu, Sha Feng, Thomas Lauvaux, Klaus Keller, Kenneth J Davis.
Dr. Feng will present: Quantification of modeled atmospheric CO2 uncertainty from various sources using ACT-America aircraft data, Sha Feng, Thomas Lauvaux, Klaus Keller, Kenneth J Davis, Peter J Rayner, Yu Zhou, Christopher A Williams, David Baker, Andrew E Schuh, S Basu, Junjie Liu.
October
Dr. Williams presented my work at the international ForestSAT conference held in College Park, MD. Thanks, Chris!
August
I enjoyed attending the Ecological Society of America annual meeting in August 2018, in New Orleans, LA. I presented in the Inspire session “Improving the Predictive Ability of the Global Carbon Cycle Models”.
May
I was 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. Her travel is funded by Summer Pruser Enhancement Award from Clark University.
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2017
September
Our paper 'The Performance of Airborne C-Band PolInSAR Data on Forest Growth Stage Types Classification' is online in Remote Sensing now! This paper proposes a classification scheme for forest growth stage types and other cover types using a support vector machine (SVM) based on the Polarimetric SAR Interferometric (PolInSAR) data acquired by the Chinese Multidimensional Space Joint-observation SAR (MSJosSAR) system. (pdf copy)
April
I was awarded the Edna Bailey Sussman Fellowship to support my summer research at the Harvard Forest LTER! I 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.
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2016
December
Our paper titled 'Drought events and their effects on vegetation productivity in China' is online in Ecosphere today! In this paper, we characterized the drought events in China from 1982 to 2012 and assessed their effects on vegetation productivity inferred from satellite data. (pdf copy)
October
I attended the Data-Driven and Simulation Science Summer School in Jena hosted by Friedrich Schiller University and the Max Planck Institute for Biogeochemistry. Enjoyed the time in Germany!
Congratulations on 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.
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2015
November
Our paper 'Contributions of natural and human factors to increases in vegetation productivity in China' is online in the Ecosphere. We analyzed the long‐term trends in vegetation productivity in China using the satellite‐derived normalized difference vegetation index (NDVI) and assessed the relationships of NDVI with a suite of natural (air temperature, precipitation, photosynthetically active radiation (PAR), atmospheric carbon dioxide (CO2) concentrations, and nitrogen (N) deposition) and human (afforestation and improved agricultural management practices) factors. (pdf copy)
March
Our paper 'Climate contributions to vegetation variations in central Asian drylands: Pre-and post-USSR collapse' is online in Remote Sensing. Our results clearly illustrate the combined influence of climatic/anthropogenic contributions on vegetation growth in Central Asian drylands. Due to the USSR collapse, this region represents a unique case study of the vegetation response to climate changes under different climatic and socio-economic conditions. (pdf copy)
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2014
April
Our paper 'Drought impact on vegetation productivity in the Lower Mekong Basin' is online in the International Journal of Remote Sensing. We assessed the impact of drought on vegetation productivity in the LMB during 2000–2011 using MOD17 products. (pdf copy)
January
Our paper 'A Comparison of Satellite-Derived Vegetation Indices for Approximating Gross Primary Productivity of Grasslands' is online in Rangeland Ecology & Management. We examined the relationships between the nine VIs derived from the moderate resolution imaging spectroradiometer (MODIS) and tower-based GPP at five eddy covariance flux sites over the grasslands of northern China. (pdf copy)