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1. A life cycle and product type based estimator for quantifying the carbon stored in wood products

   https://doi.org/10.1186/s13021-022-00220-y  

   Wei, Xinyuan; Zhao, Jianheng; Hayes, Daniel J; Daigneault, Adam; Zhu, He (December 2023, Carbon Balance and Management)

   Abstract BackgroundTimber harvesting and industrial wood processing laterally transfer the carbon stored in forest sectors to wood products creating a wood products carbon pool. The carbon stored in wood products is allocated to end-use wood products (e.g., paper, furniture), landfill, and charcoal. Wood products can store substantial amounts of carbon and contribute to the mitigation of greenhouse effects. Therefore, accurate accounts for the size of wood products carbon pools for different regions are essential to estimating the land-atmosphere carbon exchange by using the bottom-up approach of carbon stock change. ResultsTo quantify the carbon stored in wood products, we developed a state-of-the-art estimator (Wood Products Carbon Storage Estimator, WPsCS Estimator) that includes the wood products disposal, recycling, and waste wood decomposition processes. The wood products carbon pool in this estimator has three subpools: (1) end-use wood products, (2) landfill, and (3) charcoal carbon. In addition, it has a user-friendly interface, which can be used to easily parameterize and calibrate an estimation. To evaluate its performance, we applied this estimator to account for the carbon stored in wood products made from the timber harvested in Maine, USA, and the carbon storage of wood products consumed in the United States. ConclusionThe WPsCS Estimator can efficiently and easily quantify the carbon stored in harvested wood products for a given region over a specific period, which was demonstrated with two illustrative examples. In addition, WPsCS Estimator has a user-friendly interface, and all parameters can be easily modified. 

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2. The case for accurate lifetime accounting in carbon metrics

   https://doi.org/10.1145/3764944.3764965  

   Huang, Yujin; Zhu, Timothy; Gandhi, Anshul (August 2025, ACM SIGMETRICS Performance Evaluation Review)

   To represent the entire carbon footprint of computing devices, carbon metrics often include both an embodied cost (i.e., carbon cost to produce the device) and an operational cost (i.e., carbon cost to run the device). The embodied carbon cost is typically high, but it is amortized over the lifetime of the device. In this vision statement, we argue that for carbon metrics to be useful, we need (i) accurate metrics for lifetime, which are challenging for SSDs, and (ii) correct reasoning about carbon costs when using such metrics. 

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3. Anthromes and forest carbon responses to global change

   https://doi.org/10.1002/ppp3.10609  

   Hogan, J Aaron; Lichstein, Jeremy W; Helmer, Eileen H; Craig, Matthew E; Fricke, Evan; Henrich, Viola; Kannenberg, Steven A; Koven, Charles D; Goldewjik, Kees Klein; Lapola, David M; et al (July 2025, PLANTS, PEOPLE, PLANET)

   Societal Impact StatementForest ecosystems absorb and store about 25% of global carbon dioxide emissions annually and are increasingly shaped by human land use and management. Climate change interacts with land use and forest dynamics to influence observed carbon stocks and the strength of the land carbon sink. We show that climate change effects on modeled forest land carbon stocks are strongest in tropical wildlands that have limited human influence. Global forest carbon stocks and carbon sink strength may decline as climate change and anthropogenic influences intensify, with wildland tropical forests, especially in Amazonia, likely being especially vulnerable. SummaryHuman effects on ecosystems date back thousands of years, and anthropogenic biomes—anthromes—broadly incorporate the effects of human population density and land use on ecosystems. Forests are integral to the global carbon cycle, containing large biomass carbon stocks, yet their responses to land use and climate change are uncertain but critical to informing climate change mitigation strategies, ecosystem management, and Earth system modeling.Using an anthromes perspective and the site locations from the Global Forest Carbon (ForC) Database, we compare intensively used, cultured, and wildland forest lands in tropical and extratropical regions. We summarize recent past (1900‐present) patterns of land use intensification, and we use a feedback analysis of Earth system models from the Coupled Model Intercomparison Project Phase 6 to estimate the sensitivity of forest carbon stocks to CO₂and temperature change for different anthromes among regions.Modeled global forest carbon stock responses are positive for CO₂increase but neutral to negative for temperature increase. Across anthromes (intensively used, cultured, and wildland forest areas), modeled forest carbon stock responses of temperate and boreal forests are less variable than those of tropical forests. Tropical wildland forest areas appear especially sensitive to CO₂and temperature change, with the negative temperature response highlighting the potential vulnerability of the globally significant carbon stock in tropical forests.The net effect of anthropogenic activities—including land‐use intensification and environmental change and their interactions with natural forest dynamics—will shape future forest carbon stock changes. These interactive effects will likely be strongest in tropical wildlands. 

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4. Recent Advances and Challenges in Monitoring and Modeling Non-Growing Season Carbon Dioxide Fluxes from the Arctic Boreal Zone

   https://doi.org/10.1007/s40641-023-00190-4  

   Arndt, Kyle A.; Hashemi, Josh; Natali, Susan M.; Schiferl, Luke D.; Virkkala, Anna-Maria (October 2023, Current Climate Change Reports)

   Abstract Purpose of ReviewWhile previously thought to be negligible, carbon emissions during the non-growing season (NGS) can be a substantial part of the annual carbon budget in the Arctic boreal zone (ABZ), which can shift the carbon balance of these ecosystems from a long-held annual carbon sink towards a net annual carbon source. The purpose of this review is to summarize NGS carbon dioxide (CO₂) flux research in the ABZ that has been published within the past 5 years. Recent FindingsWe explore the processes and magnitudes of CO₂fluxes, and the status of modeling efforts, and evaluate future directions. With technological advances, direct measurements of NGS fluxes are increasing at sites across the ABZ over the past decade, showing ecosystems in the ABZ are a large source of CO₂in the shoulder seasons, with low, consistent, winter emissions. SummaryEcosystem carbon cycling models are being improved with some challenges, such as modeling below ground and snow processes, which are critical to understanding NGS CO₂fluxes. A lack of representative in situ carbon flux data and gridded environmental data are leading limiting factors preventing more accurate predictions of NGS carbon fluxes. 

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5. Stand density and local climate drive allocation of GPP to aboveground woody biomass

   https://doi.org/10.1111/nph.20414  

   Kannenberg, Steven_A; Babst, Flurin; Barnes, Mallory_L; Cabon, Antoine; Dannenberg, Matthew_P; Johnston, Miriam_R; Anderegg, William_R_L (January 2025, New Phytologist)

   Summary The partitioning of photosynthate among various forest carbon pools is a key process regulating long‐term carbon sequestration, with allocation to aboveground woody biomass carbon (AGBC) in particular playing an outsized role in the global carbon cycle due to its slow residence time. However, directly estimating the fraction of gross primary productivity (GPP) that goes to AGBC has historically been difficult and time‐consuming, leaving us with persistent uncertainties.We used an extensive dataset of tree‐ring chronologies co‐located at flux towers to assess the coupling between AGBC and GPP, calculate the fraction of fixed carbon that is allocated to AGBC, and understand the drivers of variability in this fraction.We found that annual AGBC and GPP were rarely correlated, and that annual AGBC represented only a small fraction (c. 9%) of fixed carbon. This fraction varied considerably across sites and was driven by differences in stand density and site climate. Annual AGBC was suppressed byc. 30% during drought and remained below average for years afterward.These results imply that assumptions of relatively stationary allocation of GPP to woody biomass and other plant tissues could lead to systematic biases in modeled carbon accumulation in different plant pools and thus in carbon residence time. 

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