Frans-Jan Parmentier

• Virkkala, Anna-Maria; Wargowsky, Isabel; Vogt, Judith; Kuhn, McKenzie A.; Madaan, Simran & Windholz, Tiffany [Vis alle 269 forfattere av denne artikkelen] (2026). ABCFlux v2: Arctic–boreal CO2 and CH4 monthly flux observations and ancillary information across terrestrial and freshwater ecosystems. Earth System Science Data. ISSN 1866-3508. 18(9), s. 6357–6409. doi: 10.5194/essd-18-6357-2026. Fulltekst i vitenarkiv Vis sammendrag

  Measurements of surface-atmosphere carbon dioxide (CO 2 ) and methane (CH 4 ) fluxes have been relatively sparse across the Arctic tundra and boreal biomes, causing significant uncertainties in carbon budget estimates from the region. While the availability of Arctic-boreal carbon flux data has increased substantially over the past decade, the data have remained spread across different repositories, scientific articles, and unpublished sources, making it difficult to leverage. Here we present a new dataset of monthly Arctic-boreal carbon fluxes (ABCFlux v2) across terrestrial (wetlands and uplands) and freshwater (lakes and rivers) ecosystems compiled from previous syntheses including the Arctic-boreal CO 2 flux database (ABCFlux v1), the Boreal-Arctic Wetland and Lake Methane Dataset (BAWLD-CH4), and the Global River Methane Database (GRiMeDB). In addition, we consider data from general-purpose (e.g., Zenodo) and flux network repositories, literature, and site principal investigators. The dataset includes surface-atmosphere CO 2 fluxes of gross primary production (GPP), ecosystem respiration (Reco), and net ecosystem exchange (NEE), alongside CH 4 fluxes. For aquatic ecosystems, we split CH 4 fluxes into diffusive and ebullitive flux pathways, and included potential emissions from transient storage in the water column (“storage fluxes”), alongside CO 2 and CH 4 concentrations dissolved in the surface water. Fluxes are measured through a variety of methods including chamber and eddy covariance techniques alongside bubble traps, ice-surveys, and concentration-based turbulence-driven modelling in aquatic ecosystems. The monthly flux data are reported together with supporting methodological and environmental metadata. The resulting ABCFlux v2 has 23 847 flux site-months, 8182 concentration site-months, and 199 seasonal observations from 1024 sites, and includes 56 139 reported fluxes (i.e. sum of GPP, Reco, NEE, and CH 4 fluxes) from the years 1984 to 2024. The majority of monthly observations occurred after 1999. Wetlands had the highest number of site-month observations (8758), followed by boreal forest (6981), lotic ecosystems (6275), lentic ecosystems (3799) and upland tundra (3308). Measurements of CO 2 dominated the dataset across most ecosystem types (25 222) except for lentic ecosystems, where CH 4 flux site-months (3098) were more frequent than CO 2 flux site-months (2915). Overall, ABCFlux v2 includes 160 % more site-months for terrestrial CO 2 flux data compared to ABCFlux v1. Integrating and updating BAWLD-CH4 flux data from growing season averages to monthly fluxes resulted in 5671 site-months of chamber CH 4 data compared to 762 site-years. This collaborative initiative, involving contributions from over 260 researchers, provides a comprehensive overview of the current state of the Arctic-boreal carbon flux network and its data, and serves as an important step in reducing uncertainties in Arctic-boreal carbon budgets and in enhancing our understanding of climate feedbacks. The data can be accessed at ORNL DAAC at https://doi.org/10.3334/ORNLDAAC/2448 (Virkkala et al., 2026).

• Giesse, Céline; Notz, Dirk; Ulrich, Mathias; Brovkin, Victor; Overduin, Pier Paul & Strauss, Jens [Vis alle 20 forfattere av denne artikkelen] (2026). Research Priorities for the Coupled Arctic Land–Ocean Carbon Cycle: Integrating Scientific and Policy Perspectives. Bulletin of The American Meteorological Society - (BAMS). ISSN 0003-0007. 107(5), s. E1159–E1169. doi: 10.1175/BAMS-D-26-0089.1. Fulltekst i vitenarkiv
• Matthes, Heidrun; Damseaux, Adrien; Westermann, Sebastian; Beer, Christian; Boone, Aaron & Burke, Eleanor [Vis alle 19 forfattere av denne artikkelen] (2025). Advances in Permafrost Representation: Biophysical Processes in Earth System Models and the Role of Offline Models. Permafrost and Periglacial Processes. ISSN 1045-6740. 36(2), s. 302–318. doi: 10.1002/ppp.2269. Fulltekst i vitenarkiv Vis sammendrag

  Permafrost is undergoing rapid changes due to climate warming, potentially exposing a vast reservoir of carbon to be released to the atmosphere, causing a positive feedback cycle. Despite the importance of this feedback, its specifics remain poorly constrained, because representing permafrost dynamics still poses a significant challenge for Earth System Models (ESMs). This review assesses the current state of permafrost representation in land surface models (LSMs) used in ESMs and offline permafrost models, highlighting both the progress made and the remaining gaps. We identify several key physical processes crucial for permafrost dynamics, including soil thermal regimes, freeze–thaw cycles, and soil hydrology, which are underrepresented in many models. While some LSMs have advanced significantly in incorporating these processes, others lack fundamental elements such as latent heat of freeze–thaw, deep soil columns, and Arctic vegetation dynamics. Offline permafrost models provide valuable insights, offering detailed process testing and aiding the prioritization of improvements in coupled LSMs. Our analysis reveals that while significant progress has been made in incorporating permafrost-related processes into coupled LSMs, many small-scale processes crucial for permafrost dynamics remain underrepresented. This is particularly important for capturing the complex interactions between physical and biogeochemical processes required to model permafrost carbon dynamics. We recommend leveraging advancements from offline permafrost models and progressively integrating them into LSMs, while recognizing the computational and technical challenges that may arise in coupled simulations. We highlight the importance of enhancing the representation of physical processes, including through improvements in model resolution and complexity, as this is a fundamental precursor to accurately incorporate biogeochemical processes and capture the permafrost carbon feedback.

• Watts, Jennifer D.; Potter, Stefano; Rogers, Brendan M.; Virkkala, Anna-Maria; Fiske, Greg & Arndt, Kyle A. [Vis alle 15 forfattere av denne artikkelen] (2025). Regional Hotspots of Change in Northern High Latitudes Informed by Observations From Space. Geophysical Research Letters. ISSN 0094-8276. 52(2). doi: 10.1029/2023GL108081. Fulltekst i vitenarkiv Vis sammendrag

  The high latitudes cover ∼20% of Earth's land surface. This region is facing many shifts in thermal, moisture and vegetation properties, driven by climate warming. Here we leverage remote sensing and climate reanalysis records to improve understanding of changes in ecosystem indicators. We applied non-parametric trend detections and Getis-Ord Gi* spatial hotspot assessments. We found substantial terrestrial warming trends across Siberia, portions of Greenland, Alaska, and western Canada. The same regions showed increases in vapor pressure deficit; changes in precipitation and soil moisture were variable. Vegetation greening and browning were widespread across both continents. Browning of the boreal zone was especially evident in autumn. Multivariate hotspot analysis indicated that Siberian ecoregions have experienced substantial, simultaneous, changes in thermal, moisture and vegetation status. Finally, we found that using regionally-based trends alone, without local assessments, can yield largely incomplete views of high-latitude change.

• Phoenix, Gareth K.; Bjerke, Jarle W.; Björk, Robert G.; Blok, Daan; Bryn, Anders & Callaghan, Terry V. [Vis alle 20 forfattere av denne artikkelen] (2025). Browning events in Arctic ecosystems: Diverse causes with common consequences. PLOS Climate. 4(1). doi: 10.1371/journal.pclm.0000570. Fulltekst i vitenarkiv Vis sammendrag

  Arctic ecosystems are experiencing extreme climatic, biotic and physical disturbance events that can cause substantial loss of plant biomass and productivity, sometimes at scales of >1000 km2. Collectively known as browning events, these are key contributors to the spatial and temporal complexity of Arctic greening and vegetation dynamics. If we are to properly understand the future of Arctic terrestrial ecosystems, their productivity, and their feedbacks to climate, understanding browning events is essential. Here we bring together understanding of browning events in Arctic ecosystems to compare their impacts and rates of recovery, and likely future changes in frequency and distribution. We also seek commonalities in impacts across these contrasting event types. We find that while browning events can cause high levels of plant damage (up to 100% mortality), ecosystems have substantial capacity for recovery, with biomass largely re-established within five years for many events. We also find that despite the substantial loss of leaf area of dominant species, compensatory mechanisms such as increased productivity of undamaged subordinate species lessen the impacts on carbon sequestration. These commonalities hold true for most climatic and biotic events, but less so for physical events such as fire and abrupt permafrost thaw, due to the greater removal of vegetation. Counterintuitively, some events also provide conditions for greater productivity (greening) in the longer-term, particularly where the disturbance exposes ground for plant colonisation. Finally, we find that projected changes in the causes of browning events currently suggest many types of events will become more frequent, with events of tundra fire and abrupt permafrost thaw expected to be the greatest contributors to future browning due to their severe impacts and occurrence in many Arctic regions. Overall, browning events will have increasingly important consequences for ecosystem structure and function, and for feedback to climate.

• Virkkala, Anna-Maria; Rogers, Brendan M.; Watts, Jennifer D.; Arndt, Kyle A.; Potter, Stefano & Wargowsky, Isabel [Vis alle 63 forfattere av denne artikkelen] (2025). Wildfires offset the increasing but spatially heterogeneous Arctic–boreal CO2 uptake. Nature Climate Change. ISSN 1758-678X. 15(2), s. 188–195. doi: 10.1038/s41558-024-02234-5. Fulltekst i vitenarkiv Vis sammendrag

  The Arctic–Boreal Zone is rapidly warming, impacting its large soil carbon stocks. Here we use a new compilation of terrestrial ecosystem CO2 fluxes, geospatial datasets and random forest models to show that although the Arctic–Boreal Zone was overall an increasing terrestrial CO2 sink from 2001 to 2020 (mean ± standard deviation in net ecosystem exchange, −548 ± 140 Tg C yr−1; trend, −14 Tg C yr−1; P < 0.001), more than 30% of the region was a net CO2 source. Tundra regions may have already started to function on average as CO2 sources, demonstrating a shift in carbon dynamics. When fire emissions are factored in, the increasing Arctic–Boreal Zone sink is no longer statistically significant (budget, −319 ± 140 Tg C yr−1; trend, −9 Tg C yr−1), and the permafrost region becomes CO2 neutral (budget, −24 ± 123 Tg C yr−1; trend, −3 Tg C yr−1), underscoring the importance of fire in this region.

• Pongracz, Alexandra; Wårlind, David; Miller, Paul A.; Gustafson, Adrian; Rabin, Sam S. & Parmentier, Frans-Jan W. (2024). Warming-induced contrasts in snow depth drive the future trajectory of soil carbon loss across the Arctic-Boreal region. Communications Earth & Environment. 5(1). doi: 10.1038/s43247-024-01838-1. Fulltekst i vitenarkiv Vis sammendrag

  The Arctic-Boreal region is projected to experience spatially divergent trends in snow depth following climate change. However, the impact of these spatial trends has remained largely unexplored, despite potentially large consequences for the carbon cycle. To address this knowledge gap, we forced a customised arctic version of the dynamic vegetation model LPJ-GUESS with daily CMIP6 outputs from a global climate model (MRI-ESM2-0) under three climate scenarios. We find that snow depths increased the most in the coldest, northernmost regions, insulating the soil, which led to increased heterotrophic respiration and reduced carbon residence times. We emphasise the need for improved projections of future snow depth - in particular diverging trends across landscapes - to more accurately simulate the strength of Arctic-Boreal carbon feedbacks and their impact on global climate.

• Milkoreit, Manjana; Boyd, Emily; Constantino, Sara M.; Hausner, Vera Helene; Hessen, Dag Olav & Kääb, Andreas [Vis alle 15 forfattere av denne artikkelen] (2024). Governance for Earth system tipping points – A research agenda. Earth System Governance. 21. doi: 10.1016/j.esg.2024.100216. Fulltekst i vitenarkiv Vis sammendrag

  Tipping points in the Earth system could be passed within the Paris Agreement's temperature goal range (1.5°C–2°C). Tipping processes are a feature of complex Earth system dynamics that present major governance challenges not addressed by existing global governance institutions. The common governance toolkit is a poor match for dealing with tipping processes, especially non-linear change, and radical intertemporality. To support the development of effective responses to anticipated, rapid state changes in the Earth system, there is an urgent need for new interdisciplinary research programs focused specifically on tipping-point governance. We distinguish two domains of action in a multi-phase framework - prevention and impact governance - and identify key research areas and questions that need to be addressed. These include developing governance principles, identifying actors and institutions that should be involved or need to be created, and determining the appropriate temporal and spatial scales for governance efforts.

• Parmentier, Frans-Jan W.; Nilsen, Lennart; Tømmervik, Hans; Meisel, Ove H.; Bröder, Lisa & Vonk, Jorien E. [Vis alle 9 forfattere av denne artikkelen] (2024). Rapid Ice‐Wedge Collapse and Permafrost Carbon Loss Triggered by Increased Snow Depth and Surface Runoff. Geophysical Research Letters. ISSN 0094-8276. 51(11). doi: 10.1029/2023GL108020. Fulltekst i vitenarkiv Vis sammendrag

  Thicker snow cover in permafrost areas causes deeper active layers and thaw subsidence, which alter local hydrology and may amplify the loss of soil carbon. However, the potential for changes in snow cover and surface runoff to mobilize permafrost carbon remains poorly quantified. In this study, we show that a snow fence experiment on High‐Arctic Svalbard inadvertently led to surface subsidence through warming, and extensive downstream erosion due to increased surface runoff. Within a decade of artificially raised snow depths, several ice wedges collapsed, forming a 50 m long and 1.5 m deep thermo‐erosion gully in the landscape. We estimate that 1.1–3.3 tons C may have eroded, and that the gully is a hotspot for processing of mobilized aquatic carbon. Our results show that interactions among snow, runoff and permafrost thaw form an important driver of soil carbon loss, highlighting the need for improved model representation. Snow cover is steadily disappearing as a result of climate change, but in areas that remain below 0°C we can still expect an increase in snow depth in the middle of winter. Since snow acts akin to a blanket, this warms the soil and accelerates the thaw of permafrost—thereby potentially contributing to carbon release from these frozen soils. Ice wedges, which are typical for permafrost landscapes, are particularly vulnerable to thaw because they hold a large amount of ice. When this ice melts, the surface sinks down, and soil carbon may be lost. In this study, we show how experimentally raised snow cover triggered the collapse of several ice wedges, not only through a warming effect of the snow but also due to an increase in the flow of water through the ice wedge network. As a result, we estimate that 1.1–3.3 tons of carbon were removed from this location, of which a portion could have entered the atmosphere as CO2. We emphasize the importance of studying the interactions among snow, runoff, and permafrost thaw to better understand how this may affect the release of greenhouse gases to the atmosphere.

• Parmentier, Frans-Jan W.; Thornton, Brett F.; Silyakova, Anna & Christensen, Torben R. (2024). Vulnerability of Arctic-Boreal methane emissions to climate change. Frontiers in Environmental Science. 12. doi: 10.3389/fenvs.2024.1460155. Fulltekst i vitenarkiv Vis sammendrag

  The rapid warming of the Arctic-Boreal region has led to the concern that large amounts of methane may be released to the atmosphere from its carbon-rich soils, as well as subsea permafrost, amplifying climate change. In this review, we assess the various sources and sinks of methane from northern high latitudes, in particular those that may be enhanced by permafrost thaw. The largest terrestrial sources of the Arctic-Boreal region are its numerous wetlands, lakes, rivers and streams. However, fires, geological seeps and glacial margins can be locally strong emitters. In addition, dry upland soils are an important sink of atmospheric methane. We estimate that the net emission of all these landforms and point sources may be as much as 48.7 [13.3–86.9] Tg CH4 yr−1. The Arctic Ocean is also a net source of methane to the atmosphere, in particular its shallow shelves, but we assess that the marine environment emits a fraction of what is released from the terrestrial domain: 4.9 [0.4–19.4] Tg CH4 yr−1. While it appears unlikely that emissions from the ocean surface to the atmosphere are increasing, now or in the foreseeable future, evidence points towards a modest increase from terrestrial sources over the past decades, in particular wetlands and possibly lakes. The influence of permafrost thaw on future methane emissions may be strongest through associated changes in the hydrology of the landscape rather than the availability of previously frozen carbon. Although high latitude methane sources are not yet acting as a strong climate feedback, they might play an increasingly important role in the net greenhouse gas balance of the Arctic-Boreal region with continued climate change.

• Treat, Claire C.; Virkkala, Anna-Maria; Burke, Eleanor; Bruhwiler, Lori; Chatterjee, Abhishek & Fisher, Joshua B. [Vis alle 32 forfattere av denne artikkelen] (2024). Permafrost Carbon: Progress on Understanding Stocks and Fluxes Across Northern Terrestrial Ecosystems. Journal of Geophysical Research (JGR): Biogeosciences. ISSN 2169-8953. 129(3). doi: 10.1029/2023JG007638. Fulltekst i vitenarkiv Vis sammendrag

  Significant progress in permafrost carbon science made over the past decades include the identification of vast permafrost carbon stocks, the development of new pan-Arctic permafrost maps, an increase in terrestrial measurement sites for CO2 and methane fluxes, and important factors affecting carbon cycling, including vegetation changes, periods of soil freezing and thawing, wildfire, and other disturbance events. Process-based modeling studies now include key elements of permafrost carbon cycling and advances in statistical modeling and inverse modeling enhance understanding of permafrost region C budgets. By combining existing data syntheses and model outputs, the permafrost region is likely a wetland methane source and small terrestrial ecosystem CO2 sink with lower net CO2 uptake toward higher latitudes, excluding wildfire emissions. For 2002–2014, the strongest CO2 sink was located in western Canada (median: −52 g C m−2 y−1) and smallest sinks in Alaska, Canadian tundra, and Siberian tundra (medians: −5 to −9 g C m−2 y−1). Eurasian regions had the largest median wetland methane fluxes (16–18 g CH4 m−2 y−1). Quantifying the regional scale carbon balance remains challenging because of high spatial and temporal variability and relatively low density of observations. More accurate permafrost region carbon fluxes require: (a) the development of better maps characterizing wetlands and dynamics of vegetation and disturbances, including abrupt permafrost thaw; (b) the establishment of new year-round CO2 and methane flux sites in underrepresented areas; and (c) improved models that better represent important permafrost carbon cycle dynamics, including non-growing season emissions and disturbance effects.

• See, Craig R.; Virkkala, Anna-Maria; Natali, Susan M.; Rogers, Brendan M.; Mauritz, Marguerite & Biasi, Christina [Vis alle 70 forfattere av denne artikkelen] (2024). Decadal increases in carbon uptake offset by respiratory losses across northern permafrost ecosystems. Nature Climate Change. ISSN 1758-678X. 14, s. 853–862. doi: 10.1038/s41558-024-02057-4. Fulltekst i vitenarkiv Vis sammendrag

  Tundra and boreal ecosystems encompass the northern circumpolar permafrost region and are experiencing rapid environmental change with important implications for the global carbon (C) budget. We analysed multi-decadal time series containing 302 annual estimates of carbon dioxide (CO2) fux across 70 permafrost and non-permafrost ecosystems, and 672 estimates of summer CO2 fux across 181 ecosystems. We fnd an increase in the annual CO2 sink across non-permafrost ecosystems but not permafrost ecosystems, despite similar increases in summer uptake. Thus, recent non-growing-season CO2 losses have substantially impacted the CO2 balance of permafrost ecosystems. Furthermore, analysis of interannual variability reveals warmer summers amplify the C cycle (increase productivity and respiration) at putatively nitrogen-limited sites and at sites less reliant on summer precipitation for water use. Our fndings suggest that water and nutrient availability will be important predictors of the C-cycle response of thes

• Keetz, Lasse Torben; Lieungh, Eva; Karimi-Asli, Kaveh; Geange, Sonya Rita; Gelati, Emiliano & Tang, Hui [Vis alle 24 forfattere av denne artikkelen] (2023). Climate–ecosystem modelling made easy: The Land Sites Platform. Global Change Biology. ISSN 1354-1013. 29(15), s. 4440–4452. doi: 10.1111/gcb.16808. Fulltekst i vitenarkiv Vis sammendrag

  Dynamic Global Vegetation Models (DGVMs) provide a state-of-the-art process-based approach to study the complex interplay between vegetation and its physical environment. For example, they help to predict how terrestrial plants interact with climate, soils, disturbance and competition for resources. We argue that there is untapped potential for the use of DGVMs in ecological and ecophysiological research. One fundamental barrier to realize this potential is that many researchers with relevant expertize (ecology, plant physiology, soil science, etc.) lack access to the technical resources or awareness of the research potential of DGVMs. Here we present the Land Sites Platform (LSP): new software that facilitates single-site simulations with the Functionally Assembled Terrestrial Ecosystem Simulator, an advanced DGVM coupled with the Community Land Model. The LSP includes a Graphical User Interface and an Application Programming Interface, which improve the user experience and lower the technical thresholds for installing these model architectures and setting up model experiments. The software is distributed via version-controlled containers; researchers and students can run simulations directly on their personal computers or servers, with relatively low hardware requirements, and on different operating systems. Version 1.0 of the LSP supports site-level simulations. We provide input data for 20 established geo-ecological observation sites in Norway and workflows to add generic sites from public global datasets. The LSP makes standard model experiments with default data easily achievable (e.g., for educational or introductory purposes) while retaining flexibility for more advanced scientific uses. We further provide tools to visualize the model input and output, including simple examples to relate predictions to local observations. The LSP improves access to land surface and DGVM modelling as a building block of community cyberinfrastructure that may inspire new avenues for mechanistic ecosystem research across disciplines.

• White, J.D.; Ahrén, D.; Ström, L.; Kelly, J.; Klemedtsson, L. & Keane, B. [Vis alle 7 forfattere av denne artikkelen] (2023). Methane Producing and Oxidizing Microorganisms Display a High Resilience to Drought in a Swedish Hemi-Boreal Mire. Journal of Geophysical Research (JGR): Biogeosciences. ISSN 2169-8953. 128(9). doi: 10.1029/2022JG007362. Fulltekst i vitenarkiv Vis sammendrag

  Abstract An increased frequency of droughts due to anthropogenic climate change can lead to considerable stress for soil microorganisms and their functioning within northern peatlands. A better understanding of the diversity and relative abundance of methane producing and oxidizing taxa, and their functional genes, can help predict the functional potential of peatlands and how the microorganisms respond to disturbances such as drought. To address knowledge gaps in the understanding of how functional genetic diversity shifts under drought conditions, we investigated a hemi boreal mire in Southern Sweden. Environmental parameters, including soil and air temperature, precipitation, and water table depth, as well as methane flux data were collected during the summer of 2017 under typical growing conditions, and in 2018 during a drought. In addition, the diversity and composition of genes encoding for methane metabolism were determined using the captured metagenomics technique. During drought we observed a substantial increase in air and soil temperature, reduced precipitation, and a lower water table depth. Taxonomic and functional gene composition significantly changed during the drought, while diversity indices, such as alpha and beta diversity, remained similar. These results indicate that methane producing and oxidizing microbial communities, and their functional genes, displayed a resilience to drought with specific genera having the ability to outcompete others under stress. Furthermore, our results show that although methane emissions are substantially reduced during drought, we can expect to see a shift toward more resilient methanogens and methanotrophs under future climate conditions.

• Tømmervik, Hans; Julitta, Tommaso; Nilsen, Lennart; Park, Taejin; Burkart, Andreas & Ostapowicz, Katarzyna Anna [Vis alle 10 forfattere av denne artikkelen] (2023). The northernmost hyperspectral FLoX sensor dataset for monitoring of high-Arctic tundra vegetation phenology and Sun-Induced Fluorescence (SIF). Data in Brief. 50. doi: 10.1016/j.dib.2023.109581. Fulltekst i vitenarkiv Vis sammendrag

  A hyperspectral field sensor (FloX) was installed in Adventdalen (Svalbard, Norway) in 2019 as part of the Svalbard Integrated Arctic Earth Observing System (SIOS) for monitoring vegetation phenology and Sun-Induced Chlorophyll Fluorescence (SIF) of high-Arctic tundra. This northernmost hyperspectral sensor is located within the footprint of a tower for long-term eddy covariance flux measurements and is an integral part of an automatic environmental monitoring system on Svalbard (AsMovEn), which is also a part of SIOS. One of the measurements that this hyperspectral instrument can capture is SIF, which serves as a proxy of gross primary production (GPP) and carbon flux rates. This paper presents an overview of the data collection and processing, and the 4-year (2019–2021) datasets in processed format are available at: https://thredds.met.no/thredds/catalog/arcticdata/infranor/NINA-FLOX/raw/catalog.html associated with https://doi.org/10.21343/ZDM7-JD72 under a CC-BY-4.0 license. Results obtained from the first three years in operation showed interannual variation in SIF and other spectral vegetation indices including MERIS Terrestrial Chlorophyll Index (MTCI), EVI and NDVI. Synergistic uses of the measurements from this northernmost hyperspectral FLoX sensor, in conjunction with other monitoring systems, will advance our understanding of how tundra vegetation responds to changing climate and the resulting implications on carbon and energy balance. Chlorophyll fluorescenceSolar Induced Fluorescence (SIF)ReflectancePhotosynthetic functionMERIS terrestrial chlorophyll index (MTCI)High-Arctic tundra

• Watts, Jennifer D.; Farina, Mary; Kimball, John S.; Schiferl, Luke D.; Liu, Zhihua & Arndt, Kyle A. [Vis alle 38 forfattere av denne artikkelen] (2023). Carbon uptake in Eurasian boreal forests dominates the high-latitude net ecosystem carbon budget. Global Change Biology. ISSN 1354-1013. 29(7), s. 1870–1889. doi: 10.1111/gcb.16553. Fulltekst i vitenarkiv
• Lambert, Marius; Tang, Hui; Aas, Kjetil Schanke; Stordal, Frode; Fisher, Rosie & Bjerke, Jarle Werner [Vis alle 8 forfattere av denne artikkelen] (2023). Integration of a Frost Mortality Scheme Into the Demographic Vegetation Model FATES. Journal of Advances in Modeling Earth Systems. 15(7). doi: 10.1029/2022MS003333. Fulltekst i vitenarkiv Vis sammendrag

  Frost is damaging to plants when air temperature drops below their tolerance threshold. The set of mechanisms used by cold-tolerant plants to withstand freezing is called “hardening” and typically take place in autumn to protect against winter damage. The recent incorporation of a hardening scheme in the demographic vegetation model FATES opens up the possibility to investigate frost mortality to vegetation. Previously, the hardening scheme was used to improve hydraulic processes in cold-tolerant plants. In this study, we expand upon the existing hardening scheme by implementing hardiness-dependent frost mortality into CLM5.0-FATES to study the impacts of frost on vegetation in temperate and boreal sites from 1950 to 2015. Our results show that the original freezing mortality approach of FATES, where each plant type had a fixed freezing tolerance threshold—an approach common to many other dynamic vegetation models, was restricted to predicting plant type distribution. The main results emerging from the new scheme are a high autumn and spring frost mortality, especially at colder sites, and increasing mid-winter frost mortality due to global warming, especially at warmer sites. We demonstrate that the new frost scheme is a major step forward in dynamically representing vegetation in ESMs by for the first time including a level of frost tolerance that is responding to the environment and includes some level of cost (implicitly) and benefit. By linking hardening and frost mortality in a land surface model, we open new ways to explore the impact of frost events in the context of global warming.

• Lambert, Marius; Tang, Hui; Aas, Kjetil Schanke; Stordal, Frode; Fisher, Rosie & Fang, Yilin [Vis alle 8 forfattere av denne artikkelen] (2022). Inclusion of a cold hardening scheme to represent frost tolerance is essential to model realistic plant hydraulics in the Arctic-boreal zone in CLM5.0-FATES-Hydro. Geoscientific Model Development. ISSN 1991-959X. 15(23), s. 8809–8829. doi: 10.5194/gmd-15-8809-2022. Fulltekst i vitenarkiv Vis sammendrag

  As temperatures decrease in autumn, vegetation of temperate and boreal ecosystems increases its tolerance to freezing. This process, known as hardening, results in a set of physiological changes at the molecular level that initiate modifications of cell membrane composition and the synthesis of anti-freeze proteins. Together with the freezing of extracellular water, anti-freeze proteins reduce plant water potentials and xylem conductivity. To represent the responses of vegetation to climate change, land surface schemes increasingly employ “hydrodynamic” models that represent the explicit fluxes of water from soil and through plants. The functioning of such schemes under frozen soil conditions, however, is poorly understood. Nonetheless, hydraulic processes are of major importance in the dynamics of these systems, which can suffer from, e.g., winter “frost drought” events. In this study, we implement a scheme that represents hardening into CLM5.0-FATES-Hydro. FATES-Hydro is a plant hydrodynamics module in FATES, a cohort model of vegetation physiology, growth, and dynamics hosted in CLM5.0. We find that, in frozen systems, it is necessary to introduce reductions in plant water loss associated with hardening to prevent winter desiccation. This work makes it possible to use CLM5.0-FATES-Hydro to model realistic impacts from frost droughts on vegetation growth and photosynthesis, leading to more reliable projections of how northern ecosystems respond to climate change.

• Oehri, Jacqueline; Schaepman-Strub, Gabriela; Kim, Jin-Soo; Grysko, Raleigh; Kropp, Heather & Grünberg, Inge [Vis alle 74 forfattere av denne artikkelen] (2022). Vegetation type is an important predictor of the arctic summer land surface energy budget. Nature Communications. 13. doi: 10.1038/s41467-022-34049-3. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Despite the importance of high-latitude surface energy budgets (SEBs) for land-climate interactions in the rapidly changing Arctic, uncertainties in their prediction persist. Here, we harmonize SEB observations across a network of vegetated and glaciated sites at circumpolar scale (1994–2021). Our variance-partitioning analysis identifies vegetation type as an important predictor for SEB-components during Arctic summer (June-August), compared to other SEB-drivers including climate, latitude and permafrost characteristics. Differences among vegetation types can be of similar magnitude as between vegetation and glacier surfaces and are especially high for summer sensible and latent heat fluxes. The timing of SEB-flux summer-regimes (when daily mean values exceed 0 Wm −2 ) relative to snow-free and -onset dates varies substantially depending on vegetation type, implying vegetation controls on snow-cover and SEB-flux seasonality. Our results indicate complex shifts in surface energy fluxes with land-cover transitions and a lengthening summer season, and highlight the potential for improving future Earth system models via a refined representation of Arctic vegetation types.

• Euskirchen, Eugénie S.; Bruhwiler, Lori M.; Commane, Róisín; Parmentier, Frans-Jan W.; Schädel, Christina & Schuur, Edward A. G. [Vis alle 7 forfattere av denne artikkelen] (2022). Current knowledge and uncertainties associated with the Arctic greenhouse gas budget. I Poulter, Benjamin; Canadell, Josep G.; Hayes, Daniel J. & Thompson, Rona Louise (Red.), Balancing Greenhouse Gas Budgets. Accounting for Natural and Anthropogenic Flows of CO2 and other Trace Gases. Elsevier. ISSN 9780128149522. s. 159–201. doi: 10.1016/B978-0-12-814952-2.00007-1. Fulltekst i vitenarkiv
• Virkkala, Anna-Maria; Natali, Susan M.; Rogers, Brendan M.; Watts, Jennifer D.; Savage, Kathleen & Connon, Sara June [Vis alle 64 forfattere av denne artikkelen] (2022). The ABCflux database: Arctic–boreal CO2 flux observations and ancillary information aggregated to monthly time steps across terrestrial ecosystems. Earth System Science Data. ISSN 1866-3508. 14(1), s. 179–208. doi: 10.5194/essd-14-179-2022. Fulltekst i vitenarkiv Vis sammendrag

  Past efforts to synthesize and quantify the magnitude and change in carbon dioxide (CO2) fluxes in terrestrial ecosystems across the rapidly warming Arctic–boreal zone (ABZ) have provided valuable information but were limited in their geographical and temporal coverage. Furthermore, these efforts have been based on data aggregated over varying time periods, often with only minimal site ancillary data, thus limiting their potential to be used in large-scale carbon budget assessments. To bridge these gaps, we developed a standardized monthly database of Arctic–boreal CO2 fluxes (ABCflux) that aggregates in situ measurements of terrestrial net ecosystem CO2 exchange and its derived partitioned component fluxes: gross primary productivity and ecosystem respiration. The data span from 1989 to 2020 with over 70 supporting variables that describe key site conditions (e.g., vegetation and disturbance type), micrometeorological and environmental measurements (e.g., air and soil temperatures), and flux measurement techniques. Here, we describe these variables, the spatial and temporal distribution of observations, the main strengths and limitations of the database, and the potential research opportunities it enables. In total, ABCflux includes 244 sites and 6309 monthly observations; 136 sites and 2217 monthly observations represent tundra, and 108 sites and 4092 observations represent the boreal biome. The database includes fluxes estimated with chamber (19 % of the monthly observations), snow diffusion (3 %) and eddy covariance (78 %) techniques. The largest number of observations were collected during the climatological summer (June–August; 32 %), and fewer observations were available for autumn (September–October; 25 %), winter (December–February; 18 %), and spring (March–May; 25 %). ABCflux can be used in a wide array of empirical, remote sensing and modeling studies to improve understanding of the regional and temporal variability in CO2 fluxes and to better estimate the terrestrial ABZ CO2 budget. ABCflux is openly and freely available online (Virkkala et al., 2021b, https://doi.org/10.3334/ORNLDAAC/1934).

• Helbig, M.; Živković, T.; Alekseychik, P.; Aurela, M.; El-Madany, T. S. & Euskirchen, E. S. [Vis alle 33 forfattere av denne artikkelen] (2022). Warming response of peatland CO2 sink is sensitive to seasonality in warming trends. Nature Climate Change. ISSN 1758-678X. 12, s. 743–749. doi: 10.1038/s41558-022-01428-z. Fulltekst i vitenarkiv Vis sammendrag

  Peatlands have acted as net CO2 sinks over millennia, exerting a global climate cooling effect. Rapid warming at northern latitudes, where peatlands are abundant, can disturb their CO2 sink function. Here we show that sensitivity of peatland net CO2 exchange to warming changes in sign and magnitude across seasons, resulting in complex net CO2 sink responses. We use multiannual net CO2 exchange observations from 20 northern peatlands to show that warmer early summers are linked to increased net CO2 uptake, while warmer late summers lead to decreased net CO2 uptake. Thus, net CO2 sinks of peatlands in regions experiencing early summer warming, such as central Siberia, are more likely to persist under warmer climate conditions than are those in other regions. Our results will be useful to improve the design of future warming experiments and to better interpret large-scale trends in peatland net CO2 uptake over the coming few decades.

• Bruhwiler, Lori; Parmentier, Frans-Jan W.; Crill, Patrick; Leonard, Mark & Palmer, Paul I. (2021). The Arctic Carbon Cycle and Its Response to Changing Climate. Current Climate Change Reports. 7, s. 14–34. doi: 10.1007/s40641-020-00169-5. Fulltekst i vitenarkiv Vis sammendrag

  The Arctic has experienced the most rapid change in climate of anywhere on Earth, and these changes are certain to drive changes in the carbon budget of the Arctic as vegetation changes, soils warm, fires become more frequent, and wetlands evolve as permafrost thaws. In this study, we review the extensive evidence for Arctic climate change and effects on the carbon cycle. In addition, we re-evaluate some of the observational evidence for changing Arctic carbon budgets. Observations suggest a more active CO2 cycle in high northern latitude ecosystems. Evidence points to increased uptake by boreal forests and Arctic ecosystems, as well as increasing respiration, especially in autumn. However, there is currently no strong evidence of increased CH4 emissions. Long-term observations using both bottom-up (e.g., flux) and top-down (atmospheric abundance) approaches are essential for understanding changing carbon cycle budgets. Consideration of atmospheric transport is critical for interpretation of top-down observations of atmospheric carbon.

• Pongracz, Alexandra; Wårlind, David; Miller, Paul A. & Parmentier, Frans-Jan W. (2021). Model simulations of arctic biogeochemistry and permafrost extent are highly sensitive to the implemented snow scheme in LPJ-GUESS. Biogeosciences. ISSN 1726-4170. 18(20), s. 5767–5787. doi: 10.5194/bg-18-5767-2021. Fulltekst i vitenarkiv Vis sammendrag

  The Arctic is warming rapidly, especially in winter, which is causing large-scale reductions in snow cover. Snow is one of the main controls on soil thermodynamics, and changes in its thickness and extent affect both permafrost thaw and soil biogeochemistry. Since soil respiration during the cold season potentially offsets carbon uptake during the growing season, it is essential to achieve a realistic simulation of the effect of snow cover on soil conditions to more accurately project the direction of arctic carbon–climate feedbacks under continued winter warming. The Lund–Potsdam–Jena General Ecosystem Simulator (LPJ-GUESS) dynamic vegetation model has used – up until now – a single layer snow scheme, which underestimated the insulation effect of snow, leading to a cold bias in soil temperature. To address this shortcoming, we developed and integrated a dynamic, multi-layer snow scheme in LPJ-GUESS. The new snow scheme performs well in simulating the insulation of snow at hundreds of locations across Russia compared to observations. We show that improving this single physical factor enhanced simulations of permafrost extent compared to an advanced permafrost product, where the overestimation of permafrost cover decreased from 10 % to 5 % using the new snow scheme. Besides soil thermodynamics, the new snow scheme resulted in a doubled winter respiration and an overall higher vegetation carbon content. This study highlights the importance of a correct representation of snow in ecosystem models to project biogeochemical processes that govern climate feedbacks. The new dynamic snow scheme is an essential improvement in the simulation of cold season processes, which reduces the uncertainty of model projections. These developments contribute to a more realistic simulation of arctic carbon–climate feedbacks.

• Parmentier, Frans-Jan W.; Nilsen, Lennart; Tømmervik, Hans & Cooper, Elisabeth J. (2021). A distributed time-lapse camera network to track vegetation phenology with high temporal detail and at varying scales. Earth System Science Data. ISSN 1866-3508. 13(7), s. 3593–3606. doi: 10.5194/essd-13-3593-2021. Fulltekst i vitenarkiv Vis sammendrag

  Near-surface remote sensing techniques are essential monitoring tools to provide spatial and temporal resolutions beyond the capabilities of orbital methods. This high level of detail is especially helpful to monitor specific plant communities and to accurately time the phenological stages of vegetation – which satellites can miss by days or weeks in frequently clouded areas such as the Arctic. In this paper, we describe a measurement network that is distributed across varying plant communities in the high Arctic valley of Adventdalen on the Svalbard archipelago with the aim of monitoring vegetation phenology. The network consists of 10 racks equipped with sensors that measure NDVI (normalized difference vegetation index), soil temperature, and moisture as well as time-lapse RGB cameras (i.e. phenocams). Three additional time-lapse cameras are placed on nearby mountains to provide an overview of the valley. We derived the vegetation index GCC (green chromatic channel) from these RGB photos, which has similar applications as NDVI but at a fraction of the cost of NDVI imaging sensors. To create a robust time series for GCC, each set of photos was adjusted for unwanted movement of the camera with a stabilizing algorithm that enhances the spatial precision of these measurements. This code is available at https://doi.org/10.5281/zenodo.4554937 (Parmentier, 2021) and can be applied to time series obtained with other time-lapse cameras. This paper presents an overview of the data collection and processing and an overview of the dataset that is available at https://doi.org/10.21343/kbpq-xb91 (Nilsen et al., 2021). In addition, we provide some examples of how these data can be used to monitor different vegetation communities in the landscape.

• Virkkala, Anna-Maria; Aalto, Juha; Rogers, Brendan M.; Tagesson, Torbern; Treat, Claire C. & Natali, Susan M. [Vis alle 49 forfattere av denne artikkelen] (2021). Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: regional patterns and uncertainties. Global Change Biology. ISSN 1354-1013. 27(17), s. 4040–4059. doi: 10.1111/gcb.15659. Fulltekst i vitenarkiv Vis sammendrag

  The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990–2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to analyze the spatial patterns and drivers of CO2 fluxes and test the accuracy and uncertainty of different statistical models. CO2 fluxes were upscaled at relatively high spatial resolution (1 km2) across the high-latitude region using five commonly used statistical models and their ensemble, that is, the median of all five models, using climatic, vegetation, and soil predictors. We found the performance of machine learning and ensemble predictions to outperform traditional regression methods. We also found the predictive performance of NEE-focused models to be low, relative to models predicting GPP and ER. Our data compilation and ensemble predictions showed that CO2 sink strength was larger in the boreal biome (observed and predicted average annual NEE −46 and −29 g C m−2 yr−1, respectively) compared to tundra (average annual NEE +10 and −2 g C m−2 yr−1). This pattern was associated with large spatial variability, reflecting local heterogeneity in soil organic carbon stocks, climate, and vegetation productivity. The terrestrial ecosystem CO2 budget, estimated using the annual NEE ensemble prediction, suggests the high-latitude region was on average an annual CO2 sink during 1990–2015, although uncertainty remains high.

Se alle arbeider i NVA

• Walsh-Vilander, Anna; Vollsnes, Ane; Berntsen, Terje Koren; Fisher, Rosie & Parmentier, Frans-Jan W. (2026). Quantifying Cold Hardening in Arctic-Boreal Vegetation using Differential Thermal Analysis. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2026). Can soil carbon content explain inter-site differences in carbon flux magnitude across the permafrost region? . Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Marchesini, Luca Belelli; Wille, Christian; Hugelius, Gustaf; Siewert, Mathias B. & Aurela, Mika [Vis alle 20 forfattere av denne artikkelen] (2026). Can soil carbon content explain inter-site differences in carbon flux magnitude across the permafrost region? doi: 10.5194/egusphere-egu26-14668. Fulltekst i vitenarkiv Vis sammendrag

  The permafrost region holds vast amounts of carbon which, upon thaw, may be released to the atmosphere as CO2 through enhanced decomposition. While links between soil carbon content and respiration have been shown by, for example, numerous incubation studies, it remains challenging to establish similar relationships from in-situ data collected in the field – especially at the large landscape-scale of eddy covariance towers. Part of the reason is the high heterogeneity of Arctic landscapes, combined with frequently shifting footprint distributions, and general lack of detailed soil carbon data that make it difficult to separate the signal from the noise. In this study, therefore, we combine detailed surveys of soil carbon content with high resolution footprint analyses to explore whether inter-site differences in carbon fluxes across ten sites spanning the Arctic can be explained by soil carbon content. Soil carbon data at each site was collected across dominant landforms and analyzed with depth. At 5 sites, these data were further developed into high resolution soil carbon maps. At the remaining sites, spatially weighted estimates of soil carbon content were determined proportionally to dominant landforms. Net CO2 fluxes collected by the towers were processed according to the same pipeline and partitioned into GPP and ecosystem respiration. These fluxes were related to the amount of soil carbon in the active layer at dominant landforms through a spatially explicit footprint analysis. Our preliminary results suggest that active layer soil carbon storage is a strong predictor of inter-site differences in ecosystem respiration during the growing season. This study will further explore the robustness of this relationship across the Arctic and throughout the year.

• Parmentier, Frans-Jan W. (2026). Det sprekker | Klassekampen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  I tundraen på Svalbard spiser klimaendringer seg inn i landskapet.

• Parmentier, Frans-Jan W. (2026). Hodet i sanden | Klassekampen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  Klimapopulisten vil at du skal lukke øynene og tro at det går over av seg selv.

• Parmentier, Frans-Jan W. (2026). Europa smelter | Klassekampen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  Hvor lenge vil vi juble over varmerekorder i Norge?

• Parmentier, Frans-Jan W. (2026). I verste fall | Klassekampen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2026). Ugler i mosen? | Klassekampen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  Våtmarkene holder på mange hemmeligheter – og tusen år gammelt karbon.

• Orndahl, Kathleen; Barrio, Isabel C; Bjerke, Jarle W.; Criado, Mariana García; Epstein, Howard & Frost, Gerald [Vis alle 14 forfattere av denne artikkelen] (2026). Bridging knowledge gaps in tundra vegetation ecology in a warmer future Arctic. doi: 10.5281/ZENODO.18749541. Fulltekst i vitenarkiv Vis sammendrag

  The Arctic is warming nearly four times faster than the rest of the planet (Rantanen et al., 2022). Arctic tundra ecosystems are responding to these rapid climate changes and subsequent environmental changes in myriad ways, with implications for wildlife habitats, permafrost, land-atmosphere interactions and regional climate, the global carbon cycle, Arctic Indigenous and local communities, and more. One of the strongest central tendencies of Arctic environmental change on land has been an increase in the aboveground biomass and productivity (“greenness”) of tundra vegetation. However, the Arctic tundra as a whole has exhibited a variety of vegetation responses – not only regional and localized increases in biomass and productivity (“greening”), but also decreases (“browning”), and stability (little or no change in vegetation). While remotely-sensed spectral indices such as the Normalized Difference Vegetation Index are useful proxies for ecosystem conditions and responses, with a period-of-record approaching 45 years, they also have significant limitations. Many knowledge gaps remain in interpreting long-term trends (and stability), while process models face considerable challenges in accurately projecting future responses as the Arctic continues to warm. Given the high variability in ecosystem trends at the landscape scale, our knowledge base for many parts of the Arctic remains sparse. Strong interactions and feedbacks among vegetation, herbivores, decomposers, permafrost, soil hydrology, temperature regime, albedo, sea ice conditions, and disturbance further impact system dynamics.

• Parmentier, Frans-Jan W. (2026). Rarere vintervær. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  Hvordan kan vi få naturbranner midt i sprengkulda?

• Parmentier, Frans-Jan W. (2026). Too big to fail. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv Vis sammendrag

  Trump vil stenge et ikonisk forskningsinstitutt. Det kan bli en katastrofe for klimavitenskapen, også i Norge.

• Parmentier, Frans-Jan W. (2025). The Arctic-Boreal Methane Budget. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Weirder winter weather and its varying impacts on the Arctic-boreal carbon cycle. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Contrasting shifts in snow depth as a driver of vegetation damage and soil carbon loss across the Arctic-Boreal region. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Why weirder winter weather is worrisome: impacts on vegetation damage and permafrost carbon loss. Fulltekst i vitenarkiv
• Vollsnes, Ane; Fisher, Rosie & Parmentier, Frans-Jan W. (2025). Vinterklima og vegetasjon. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Pongracz, Alexandra; Lambert, Marius; Fisher, Rosie; Gustafson, Adrian & Miller, Paul A. [Vis alle 9 forfattere av denne artikkelen] (2025). Contrasting shifts in snow depth as a driver of vegetation damage and soil carbon loss across the Arctic-Boreal region. doi: 10.5194/egusphere-egu25-16730. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Uforståelig. Klassekampen. ISSN 0805-3839. s. 3–3. doi: https:/klassekampen.no/artikkel/2025-12-02/uforstaelig. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Fornektelsen. Klassekampen. ISSN 0805-3839. s. 3–3. doi: https:/klassekampen.no/artikkel/2025-09-23/fornektelsen. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Klima­skeptikerne er tilbake. Klassekampen. ISSN 0805-3839. s. 2–3. doi: https:/klassekampen.no/utgave/2025-08-11/klimaskeptikerne-er-tilbake. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Noe er nytt under sola. Klassekampen. ISSN 0805-3839. s. 2–3. doi: https:/klassekampen.no/utgave/2025-07-07/noe-er-nytt-under-sola. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Vi står på skuldrene til kjemper. Klassekampen. ISSN 0805-3839. s. 2–3. doi: https:/klassekampen.no/utgave/2025-05-19/vi-star-pa-skuldrene-til-kjemper. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Spillet om Grønland. Klassekampen. ISSN 0805-3839. s. 2–3. doi: https:/klassekampen.no/utgave/2025-04-07/spillet-om-gronland. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Om isen er borte, kan vi vel bare lage ny? Klassekampen. ISSN 0805-3839. s. 2–3. doi: https:/klassekampen.no/utgave/2025-03-03/om-isen-er-borte-kan-vi-vel-bare-lage-ny. Fulltekst i vitenarkiv
• Virkkala, Anna-Maria; Rogers, Brendan M.; Watts, Jennifer D.; Arndt, Kyle A.; Potter, Stefano & Wargowsky, Isabel [Vis alle 63 forfattere av denne artikkelen] (2025). Correction to: Wildfires offset the increasing but spatially heterogeneous Arctic–boreal CO2 uptake (Nature Climate Change, (2025), 15, 2, (188-195), 10.1038/s41558-024-02234-5). Nature Climate Change. ISSN 1758-678X. 15(3), s. 335–335. doi: 10.1038/s41558-025-02279-0. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2025). Trumps nye klima. Klassekampen. ISSN 0805-3839. s. 2–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Pongracz, Alexandra; Miller, Paul A.; Wårlind, David; Rabin, Sam S. & Gustafson, Adrian [Vis alle 14 forfattere av denne artikkelen] (2024). Local and regional impacts of changing snow cover on permafrost carbon loss. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Marchesini, Luca Belelli; Wille, Christian; Hugelius, Gustaf; Siewert, Matthias Benjamin & Aurela, Mika [Vis alle 21 forfattere av denne artikkelen] (2024). Does soil carbon content explain inter-site differences in ecosystem respiration across the permafrost region? Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2024). En sang om is og trær. Klassekampen. ISSN 0805-3839. s. 2–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2024). Hvem har skapt metanmons­teret? Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2024). Kan naturen forhandles som en pengesum? Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Pongracz, Alexandra; Miller, Paul A.; Wårlind, David; Rabin, Sam S. & Gustafson, Adrian [Vis alle 14 forfattere av denne artikkelen] (2024). Local and regional impacts of changing snow cover on permafrost carbon loss. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2024). Forskning er ikke nok til å forstå hva som skjer i Arktis. Klassekampen. ISSN 0805-3839. s. 2–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2024). Snøkaos og klimakaos. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2024). Vi trenger en Marshallplan for offshoreindustrien. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2024). Når et tre brenner uten at noen måler det. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Pongracz, Alexandra; Wårlind, David; Miller, Paul A.; Rabin, Sam S.; Gustafson, Adrian & Parmentier, Frans-Jan (2023). Contrasting trends in snow thickness govern future trajectories of Arctic-boreal carbon release. Fulltekst i vitenarkiv
• Lambert, Marius; Tang, Hui; Aas, Kjetil Schanke; Stordal, Frode; Bjerke, Jarle Werner & Fisher, Rosie [Vis alle 10 forfattere av denne artikkelen] (2023). Winter survival of vegetation in the Arctic-boreal region: Integrating cold hardiness and frost mortality schemes into CLM-FATES. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Vi ser ikke skogen for bare trær. Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Regjeringens grønne bok er full av eventyr. Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Når isbreene smelter, renner også klima­his­to­rien ut i havet. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Et varmt ­mysterium i verdenshavene. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Nå er det motorveiens tur. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2023). Vellykket klima­aktivisme handler ikke om seg selv. Klassekampen. ISSN 0805-3839. s. 2–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Hvordan skal vi møte den neste «Hans»? Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan (2023). Mens isen smelter, gir regjeringen bånn gass. Klassekampen. ISSN 0805-3839. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Vinterskader: Hvordan påvirkes naturen av ekstremt vintervær og vintertørke? Fulltekst i vitenarkiv
• Aas, Kjetil Schanke; Lambert, Marius; Tang, Hui; Althuizen, Inge; Berntsen, Terje Koren & Fisher, Rosie [Vis alle 11 forfattere av denne artikkelen] (2022). Recent high-latitude vegetation developments in CLM-FATES. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan; Hessen, Dag Olav & Wang, You-Ren (2022). Ekstremoppvarmingen av Arktis gir økte CO2-utslipp. Dagens næringsliv. ISSN 0803-9372. s. 31–31. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Full gass inn i krisa. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Lambert, Marius S. A.; Tang, Hui; Aas, Kjetil Schanke; Stordal, Frode; Fisher, Rosie & Bjerke, Jarle W. [Vis alle 7 forfattere av denne artikkelen] (2022). Towards realistic plant hydraulics and frost damage in the Arctic-Boreal Zone by modelling cold acclimation in CTSM5-Fates (hydro). Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W.; Nilsen, Lennart; Tømmervik, Hans & Cooper, Elisabeth J. (2022). A distributed time-lapse camera network on high-arctic Svalbard to track vegetation phenology with high temporal detail and at varying scales. Fulltekst i vitenarkiv
• White, Joel D.; Ahrén, Dag; Ström, Lena; Klemedtsson, Leif & Parmentier, Frans-Jan W. (2022). Methane producing and reducing microorganisms display a high resilience to the effects of short term drought in a Swedish hemi boreal fen. Fulltekst i vitenarkiv
• Pongracz, Alexandra; Wårlind, David; Miller, Paul A. & Parmentier, Frans-Jan W. (2022). Quantifying the impact of winter warming on arctic-boreal ecosystems and greenhouse gas exchange. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Adjø, Sibir. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Langt, langt borte. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Hjelp fra vulkanen? Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Klimaendring er ikke som ­å skru opp varmen med en grad. Klassekampen. ISSN 0805-3839. s. 2–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). På vippepunktet. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2022). Blokk til blokk. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Pongracz, Alexandra; Wårlind, David; Miller, Paul A. & Parmentier, Frans-Jan W. (2021). Quantifying the impact of wintertime changes on the arctic carbon cycle. Fulltekst i vitenarkiv
• Helbig, Manuel; Zivkovic, Tatjana; Alekseychik, Pavel; Aurela, Mika; Euskirchen, Eugénie S. & Flanagan, Lawrence B. [Vis alle 27 forfattere av denne artikkelen] (2021). Early but not late growing season warming enhances peatland net ecosystem carbon dioxide uptake. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Flytende Jord. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Pastorello, Gilberto; Trotta, Carlo; Canfora, Eleonora; Chu, Housen; Christianson, Danielle & Cheah, You-Wei [Vis alle 288 forfattere av denne artikkelen] (2021). Author Correction: The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data (Scientific Data, (2020), 7, 1, (225), 10.1038/s41597-020-0534-3). Scientific Data. 8(1). doi: 10.1038/s41597-021-00851-9. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Negativ tenkning. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Zombier i skogen. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Helt på jordet. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Ko-ko-klima! Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Hvit jul for Rudolf. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Tjoflot, Gunn Kristin & Parmentier, Frans-Jan W. (2021). Fægriprisen 2021 tildelt Frans-Jan W. Parmentier for artikkel om permafrost. [Internet]. Titan.uio.no. Fulltekst i vitenarkiv Vis sammendrag

  Forsker Frans-Jan Parmentier ved Institutt for geofag og CBA er tildelt årets Fægripris for artikkelen Permafrost: Den sovende klimakjempen.

• Parmentier, Frans-Jan W.; Nilsen, Lennart; Tømmervik, Hans & Cooper, Elisabeth J. (2021). A distributed time-lapse camera network on high-arctic Svalbard to track vegetation phenology with high temporal detail and at varying scales. Fulltekst i vitenarkiv Vis sammendrag

  Near-surface remote sensing techniques are essential monitoring tools to provide spatial and temporal resolutions beyond the capabilities of orbital methods. This high level of detail is especially helpful to monitor specific plant communities and to accurately time the phenological stages of vegetation – which satellites can miss by days or weeks in frequently clouded areas such as the Arctic. Therefore, we established a measurement network that is distributed across varying plant communities in the high arctic valley of Adventdalen on the Svalbard archipelago, with the aim to monitor vegetation phenology. The network consists of ten racks equipped with sensors that measure NDVI (Normalized Difference Vegetation Index), soil temperature and moisture, as well as time-lapse RGB cameras. Three additional time-lapse cameras are placed on nearby mountain tops to provide an overview of the valley. From these RGB photos we derived the vegetation index GCC (Green Chromatic Channel), which has similar applications as NDVI but at a fraction of the cost of NDVI imaging sensors. To create a robust timeseries for GCC, each set of photos was adjusted for unwanted movement of the camera with a stabilizing algorithm that enhances the spatial precision of these measurements. We show how this data can be used to monitor different vegetation communities in the landscape and that this can form the basis for a direct comparison to space-borne observations and further upscaling.

• Lambert, Marius; Aas, Kjetil Schanke; Tang, Hui; Stordal, Frode & Parmentier, Frans-Jan (2021). Modelling insights into the effects of hardening during extreme winter root water release. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Norske oljemyter. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv
• Parmentier, Frans-Jan W. (2021). Ingen unnskyldninger. Klassekampen. ISSN 0805-3839. s. 3–3. Fulltekst i vitenarkiv

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