Themes at the ICOS Science Conference 2020

The showcase will be open thorough the conference!

Abstracts

• 400. Steinhoff, Tobias: The first ICOS OTC pCO2 instrumentation inter-comparison

Conveners: Ana Bastos, Wouter Peters, Philippe Ciais

The frequency and intensity of climate extremes has been made more likely by anthropogenic climate change. Over the past decades, record-breaking droughts, heatwaves or heavy floods have been registered, with severe impacts on societies, economies and ecosystems. Understanding how climate extremes affect ecosystem water, carbon and energy cycling, and how resilient different ecosystems are to these events is fundamental to anticipate future impacts on ecosystems’ functioning and the services they provide to societies. A more comprehensive understanding of these impacts is now possible due to well established in-situ observation networks, remote-sensing products and the improvement of process-based modelling.

This session seeks contributions focusing on the impacts of recent extreme events on the diverse ecosystem processes, as well as on the long-term mortality and post-disturbance recovery trajectories. The analysis of compound events (e.g. drought and heat) and of cascading impacts (e.g. storms and insect outbreaks) is of particular interest to this session. The session will cover contributions from in-situ, remote-sensing and modelling approaches, with a special focus on integrative approaches.

Subtheme 1.2: Emerging mechanisms of ecosystem functioning in a warmer and drier world

Conveners: Jose Gruenzweig, Ana Rey, Anders Lindroth (TBC)

Over the past decades, we have gained much knowledge on how ecosystems respond to a warmer and drier climate that often involves extreme heat and drought events. These responses concern processes of ecosystem functioning that are conventionally studied in most biomes. However, responses to climate change may include an unprecedented shift from commonly studied mechanisms of ecosystem functioning to a set of mechanisms that are prevalent in drylands, but are ‘novel’ to most other climatic zones. We envision that with continued climate change, mechanisms and drivers that commonly control ecosystem functioning in drylands become widespread in non-xeric regions of the world. These ‘dryland mechanisms’ include landscape-scale processes, such as horizontal resource redistribution, self-organization of vegetation patterns and decoupling of biogeochemical cycles.

Ecosystem-scale processes include drying-wetting cycles of soils leading to pulses of biological activity, hydraulic redistribution of water in soils by roots, and biotic processes enhanced by non-rainfall water sources, such as dew. Extreme heat induces trace gas emissions and thermal degradation of organic matter, while intense solar radiation degrades surface organic materials by photochemical processes. With many climatic zones experiencing more pronounced warm and dry weather, it is critical to include these ‘novel’ mechanisms to better understand and predict global ecosystem responses to future climate conditions.

The drought that hit Europe during 2018 had profound effects on some ecosystems with carbon balances turning from strong sinks to neutrality. Situations like this are extremely valuable for testing and developing ecosystem models to be used in climate models. Also the recovery after a severe drought is important to understand.

This session welcomes papers related to the 2018 drought, more general effects on evaporation and energy fluxes as well as on how ecosystems respond to a warmer and drier climate.

Plenary presentations in Theme 1

• 70. Thompson, Rona: Changes in Net Ecosystem Exchange over Europe During the 2018 Drought Based on Atmospheric Inversions

Oral presentations in Theme 1

Part of Session 8 and Session 14.

• 23. Xenakis, Georgios: Impact of the 2018 drought on carbon, water and energy exchange of a mature Sitka spruce and a restock site on organo-mineral soil
• 35. Migliavacca, Mirco: How nutrient and water availability impact carbon fluxes in a semi-arid tree-grass ecosystem
• 36. Gharun, Mana: Ecosystem functioning and recovery after two consecutive extreme years in Switzerland
• 83. Sathyanadh, Anusha: Impact of the 2018 drought on the carbon balance of terrestrial ecosystems in Northern Sweden - integrating measurements and modelling.
• 105. Sanders, Richard: The Integrated Ocean Carbon Observing System
• 143. Rehder, Gregor: Extreme productivity patterns during the spring bloom 2018 in the central Baltic Sea suggest vertical nutrient shuttling: Unforeseen surprises for the fight against eutrophication in a warming world?
• 147. Buysse, Pauline: Short-term impacts of the summer 2019 heatwave on ecosystem functioning inferred from ICOS flux towers in France
• 163. Gourlez de la Motte, Louis: Non-stomatal processes reduce gross primary productivity in temperate forest ecosystems during severe edaphic drought
• 173. Smith, Naomi: Spring enhancement and summer reduction in carbon uptake during the 2018 drought in northwestern Europe
• 195. Rinne, Janne: Effect of the 2018 drought on methane and carbon dioxide exchange of northern mire ecosystems

Poster presentations in Theme 1

• 16. Arora, Parth: Vulnerability of intertidal seagrass patches from fungal diseases from the coast of South Andaman, India
• 43. Ericson, Ylva: Spatiotemporal variability of the surface water aragonite saturation state in the western Barents Sea
• 48. Migliavacca, Mirco: The global coordination of ecosystem functional properties
• 50. Park, Hoonyoung: Unseasonal vegetation seasonality in CMIP5 and CMIP6 simulations
• 56. Stocker, Benjain: Can we sense plant rooting depth from above?
• 59. Kowalska, Natalia: Analysis of floodplain forest sensitivity to drought
• 60. Herberich, Maximiliane: Resistance and resilience of semi-natural plant communities to extreme drought
• 62. van den Brink, Liesbeth: The role of drought on element release and the velocity of litter decomposition
• 106. Zenone, Terenzio: Biological and Environmental Controls on Evaporative Fraction of a multi-cropland site in southern Italy
• 179. Arriga, Nicola: Two decades of carbon, water and energy fluxes from a mediterranean pine forest: San Rossore ◄ 
• 200. Dare-Idowu, Oluwakemi: Hydrological functioning of irrigated maize crops in southwest France using Eddy Covariance measurements and a land surface model
• 208. Beauclaire, Quentin: Proofs of non-stomatal limitations of potato photosynthesis during drought by using eddy covariance data

Conveners: Leena Järvi, Andreas Christen, Kevin Gurney

•    Novel urban monitoring networks and platforms
•    Micrometeorological measurements of local-scale emissions and sinks
•    Emission inventories including emission and uptake hotspots
•    Atmospheric observations of urban greenhouse gas plumes
•    Uncertainties in urban greenhouse gas budgets obtained with different methods

Urban areas are major contributor to total anthropogenic greenhouse gas (GHG) emissions. Understanding in detail the total emissions of urban GHGs, their temporal and spatial distributions, including sinks, is a key for reducing emissions and identifying effective emissions reduction strategies. Urban observations, modelling, and spatiotemporally-explicit bottom-up estimation of GHG emissions can enable an independent evaluation for self-reported emission inventories. Different approaches for the urban GHG emission estimation exist - ranging from micrometeorological emission measurements and isotope analyses to urban scale concentration monitoring and modelling. Novel city-wide measurement platforms including mobile observations and advanced high-resolution bottom-up flux estimation are emerging. At the same time, advances in ground-based and satellite remote sensing allow for complementary estimation for urban greenhouse gas emissions.

This session will bring together the different methodologies used to examine and understand urban greenhouse gas budgets, their emissions and sinks, and dependencies on different environmental factors at different scales. We further welcome contributions that showcase how urban GHG estimation can be integrated in networks, such as WMO IG3IS.We welcome contributions based on conceptual, experimental, observational or modelling approaches.

Plenary presentations in Theme 2

• 164. Järvi, Leena: CarboCity project – A novel quantification and description of urban biogenic fluxes

Oral presentations in Theme 2

Part of Session 1 and Session 7.

• 28. Prunet, Pascal: Plume detection and characterization from XCO2 imagery: Evaluation of Gaussian methods for quantifying plant and city fluxes
• 49. Dellaert, Stijn: Compiling a more complete inventory of public power and heat plant point source emissions in the EU
• 51. Park, Chaerin: Tracking the Nature of Urban Carbon Cycle – the Introduction of Megacity CO₂ – Seoul Project
• 86. Hammer, Samuel: Monitoring ffCO₂ emission hotspots using atmospheric ¹⁴CO₂ measurements
• 88. van der Woude, Auke: In tandem optimisation of anthropogenic and biosphere CO₂ emissions using a simple fossil fuel emission model and C¹⁴
• 102. Stagakis, Stavros: Quantifying biogenic carbon dioxide fluxes in an urban area
• 144. Havu, Minttu: Improved understanding of urban street tree and soil carbon cycle
• 187. Thomas, Kaminski: Assessing the constraint of the CO2 monitoring mission on fossil fuel emissions from power plants and a city in a regional carbon cycle fossil fuel data assimilation system
• 189. Zazzeri, Giulia: Efficient sampling of atmospheric methane for radiocarbon analysis
• 201. Vogel, Felix: Urban greenhouse gas monitoring in the Greater Toronto Region, Canada

Poster presentations in Theme 2

• 25. Super, Ingrid: Uncertainties in a high-resolution gridded emission map and the importance for urban scale emission verification
• 38. Leuenberger, Markus: Continuous observation of CO₂, O₂ and radon in Bern city are complemented with their stable isotope measurements to partition CO₂ emissions into biogenic and specific fossil fuel contributions
• 44. Gurney, Kevin: The CO2 Emissions of US Cities: Status, Dynamics, and Comparisons
• 53. Liu, Yunsong: Mobile measurement of carbon dioxide and methane emissions in Cyprus
• 54. Park, Hayoung: Assessing Emission Characteristics of Cities Using Satellite-based Observations of CO2, CO, and NO2
• 77. Nathan, Brian: Tests and Implementation of a Dense-Network Urban PM2.5 Inversion System
• 99. Feig, Gregor: Development of a long term environmental research infrastructure in South Africa
• 107. Leuenberger, Markus: Evaluation of the measurement quality through the comparison of two high alpine CO2 records at the Jungfraujoch (Switzerland)
• 115. Zheng, Bo: The potential of satellite spectro-imagery for monitoring anthropogenic CO₂ emissions from large point sources and cities in Europe
• 127. He, Wei: Evaluating anthropogenic CO2 emissions of China estimated from atmospheric inversions of “proxy” species against tower CO2 measurements
• 136. Nitzsche, Leonard: A Dual Frequency Comb spectrometer suited for open-path greenhouse gas and trace gas detection
• 146. Feigenwinter, Christian: Towards ICOS labelling of urban sites - review of ICOS protocols from an urban perspective
• 149. di Sarra, Alcide: Impact of a landifll fire on the atmospheric greenhouse gases and aerosol properties at Lampedusa
• 156. Fleming, Leigh: Evaluating the performance of a Picarro G2207-i O₂ analyser in real-world applications
• 158. Rivera Martinez, Rodrigo Andres: Performance of low-cost metal oxide sensors in the reconstruction of CH₄ observations at background levels and at artificial high levels generated in laboratory.
• 165. Krautwurst, Sven: Quantifying CH₄ coal mine emissions in Upper Silesia by passive airborne remote sensing observations during CoMet
• 171. Eckhardt, Henrik: Atmospheric Δ₄₇ as a tracer for local atmospheric CO₂ sources and sinks - a theoretical analysis of mixing effects

Conveners: Daniel Mayor, Richard Sanders, Stacey Felgate, Chris Evans, Zhiliang Zhu, Lisamarie Windham-Myers, Peng Gong, Gyami Shrestha, Richard Sanders, Michele Giani, Agneta Fransson and Vassilis Kitidis, Meike Becker, Thanos Gkritzalis

The interfaces of land, water and atmosphere are a critical research and monitoring priority of carbon and other greenhouse gas (GHG) fluxes:
i)    Wetland ecosystems store significant pools of carbon, and significantly influence global carbon budgets via emissions of CO2 and methane.
ii)    The flow of terrigenous organic matter (tOM), sediments and dissolved carbon across the land-ocean aquatic continuum is a significant and increasing component of the global C cycle
iii)    Shelf seas play key roles in the global C cycle and the ocean carbon sink via the continental shelf pump which absorbs CO2 at the surface and transfers it to deep water
Measuring and accounting for these fluxes in these systems and understanding what controls them across different scales in space and time is challenging due to their high variability, poor representation in maps and models and the relatively small number of high accuracy observations.

In this theme we plan several sessions to bring together researchers from different fields in order to investigate the similarities, differences and links in our studies.

We invite studies (observational (remote sensing and fieldwork), experimental, theoretical and technological perspectives) focusing on:
•    Coastal tidal wetlands and nontidal inland freshwater wetlands
•    Quantifying and understanding land-ocean tOM fluxes
•    The role of estuarine environments in the ocean carbon sink and how they are responding to resource exploitation and climate change
•    Constraining fluxes at the marine boundary layer and the associated uncertainties

Plenary presentations in Theme 3

• 67. Wu, Mousong: Using SMOS soil moisture data combining CO2 flask samples to constrain carbon fluxes during 2010-2015 within a Carbon Cycle Data Assimilation System (CCDAS)
• 110. Sanders, Richard: Carbon Cycling along the GB Land Ocean Aquatic Continuum (LOAC)

Oral presentations in Theme 3

Part of Session 4 and Session 10.

• 22. Legge, Ollie: Carbon on the northwest European shelf: contemporary budget and future influences
• 37. Cooper, Chiara: Dissolved organic matter dynamics across East Anglian river-to-North Sea salinity gradients
• 41. Gkritzalis, Thanos: Estimations of air-sea carbon flux based on in situ CO₂ measurements at the Belgian Continental Shelf
• 120. Sokolowsky, Liv: Poor vegetation growth after grassland renewal initially turns bog peatland with submerged drains into a large greenhouse gas source
• 125. Esters, Leonie: Evaluation of a turbulence-based description of the air-water gas transfer velocity
• 130. Felgate, Stacey: Pan-European monitoring of land-ocean-atmosphere carbon fluxes along the aquatic continuum ◄ 
• 140. Parampil, Sindu: Changes in atmospheric CO₂ over oceans from OCO-2
• 157. Kitidis, Vassilis: A Carbon-budget for the north-west European shelf - limitations and uncertainties.
• 160. Matthews, Ruth: Quantifying the fluxes of inorganic carbon and alkalinity through UK estuaries
• 176. Pickard, Amy: Greenhouse gas concentrations and fluxes from seven UK estuaries

Poster presentations in Theme 3

• 66. Mäki, Mari: Forest floor CO2 effluxes along a latitudinal gradient
• 76. Koch, Frank-Thomas: Evaluation of model-data mismatch errors in the CarboScope-Regional Inversion System
• 98. Lefevre, Lodewijk: CongoFlux: the first flux tower of the Congo Basin Forest
• 103. Canning, Anna: The Danube River Delta: CO₂ and CH₄ sources and sinks
• 123. Humphreys, Matthew: Preliminary results from a national programme monitoring seasonal variability in air-sea CO₂ exchange and seawater pH in the intermittently stratified “transition zone” of the North Sea
• 124. Fransson, Agneta: Storms and sea-ice processes in the high Arctic Ocean enhance wintertime ocean CO₂ uptake
• 151. Taborski, Tom: Quantifying and revisiting canopy stomatal conductance above the maritime pine FR-Bil ICOS station, France
• 166. Agusti-Panareda, Anna: Using ICOS flux data to estimate prior uncertainty and its impact on simulated variability of atmospheric CO2
• 184. Rutgersson, Anna: Using land-based stations for air-sea interaction studies, issues with land influence and non-stationarity
• 188. Giani, Michele: Alkalinity and dissolved inorganic carbon transported by rivers into the northern Adriatic Sea
• 198. Mänd, Pille: Do climate-driven changes in tree hydraulics and osmolality affect VOC and NOx emissions from silver birches?
• 199. Munassar, Saqr: Impact of applying various prior flux products on estimating CO2 fluxes derived from the Jena Carboscope regional inversion system

When designing and implementing the ICOS Research Infrastructure and its observational networks, a huge effort has been put into measurement precision, compatibility and accuracy. Here we aim at evaluating and discussing the success of this effort, concerning, on one hand, the measurements themselves and their representativeness but also their value for our ability to quantify European and global GHGs fluxes and budgets.
The main question to be addressed in this topic is how well ICOS RI and its users have proceeded in the aim to better understand the driving processes of GHGs exchange, to enable future projections and to provide input for supporting the Paris agreement e.g. by supporting monitoring and verification as well as future Global Stocktake efforts. 
The theme invites presentations assessing our current measurement uncertainties and their quantification, the completeness and representativeness of the existing networks, and finally the integration of bottom‐up versus top‐down flux estimates. Furthermore, it will focus on some detailed questions:

Subtheme 4.1: Laser scanning technologies for innovative forest monitoring

Conveners: Miro Demol, Crystal L Schaaf, Jan van Aardt, Bert Gielen

Continued advancements in 3D scanning equipment and software open up a variety of new  perspectives on how we can map and monitor our surroundings. In a forest environment, terrestrial  laser scanning (TLS) can capture full 3D pointclouds of the environment, in relatively fast way and  with an astonishing level of detail. This has sparked interest in the use of TLS for measuring  traditional forest inventory metrics, such as tree diameter and height, crown dimension and stem  positions, but its greatest potential lies in measuring novel structural tree properties, such as woody  biomass, aboveground root structures, and even foliar structural properties, that were practically  impossible to quantify at this level of detail, accuracy, and precision before. In this session, we want  to explore the potential contribution of TLS for improved forest monitoring, detailed assessments of  complex forest structures, and investigate how TLS integrates with other sensors and platforms.

Subtheme 4.2: The use of mobile measurements and modeling for emissions quantification and mitigation

Conveners: Felix Vogel, Thomas Röckmann

Long time observations of greenhouse gas concentration are indispensable for monitoring global and regional trends in atmospheric greenhouse gas concentrations on large scales. However, emissions and emission reduction actions happen at the local scale where emission estimates usually rely on “bottom-up” assessments using activity data and emission factors. The underlying emission factors are often not site specific or independently confirmed by top-down measurements. Recently developed mobile greenhouse gas analyzers are increasingly used to bridge the scale between continuous observations at fixed sites and the local emissions from individual sources, facilities or limited regions. Many mobile studies have uncovered previously unknown sources, as well as significant differences in emission factors which can differ widely even for similar sources in a region or a emission category.

We invite contributions that focus on the use of mobile measurements or novel evaluation tools of such mobile measurements for quantification of greenhouse gas emissions, and emission reduction.

Subtheme 4.3: Soil GHG exchange – from techniques to data analysis (past, present and future)

Conveners: Manuel Acosta, Jukka Pumpanen, Ralf Kiese

Soils act as sources and sinks for greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Even though, last decades a significant advance regarding soil GHG fluxes studies at different ecosystems have done, there still issues and shortcomings to be solved.  On the other hand, new techniques to improve the versatility of soil GHG measurements and data interpretation have been introduced the last couple of years. Since both storage and emission capacities may be large, precise quantifications are needed to obtain reliable soil global budgets that are necessary for land-use management (agriculture, forestry), global change and for climate research.
This section invites studies addressing the soil fluxes-related processes of any of the three GHGs and their influencing parameters, studies involving techniques for GHG measurements and studies regarding soil GHG data processing and interpretation.

Subtheme 4.4: Estimating uncertainties of ICOS measurement data and their implication for the uncertainty of European (and global) GHGs budgeting

Conveners: Ingeborg Levin and Ute Karstens

The main question to be addressed in this session is how far are ICOS RI and its users from the aim to better understand the governing processes of GHGs exchange to enable future projections and provide input for, and possibly allow verification of, e.g. the Paris agreement. When designing and implementing the ICOS Research Infrastructure and its observational networks, huge effort has been put into measurement precision, compatibility and accuracy. Here we aim at evaluating and discussing the success of this effort, concerning, on one hand, the measurements themselves and their representativeness but also their value for our ability to quantify European and global GHGs fluxes and budgets. The session invites presentations assessing our current measurement uncertainties and their quantification, the completeness and representativeness of the existing networks, and finally the integration of bottom‐up versus top‐down flux estimates.

Plenary presentations in Theme 4

• 45. Petrescu, A.M.Roxana: A synthesis of European greenhouse gas emissions and their uncertainties
• 117. Kelly, Julia: Thermal cameras: a new tool for modeling and upscaling ecosystem respiration?

Oral presentations in Theme 4

Part of Session 3, Session 9, and Session 15.

• 21. Darenova, Eva: Effect of summer drought on soil CO₂ efflux in four forest ecosystems
• 34. Keppler, Lydia: Reconstructing sub-surface Dissolved Inorganic Carbon from observations in the Southern Ocean
• 55. Jocher, Georg: Assessing decoupling of above and below canopy air masses and its biasing influence on EC derived forest carbon budgets at a Norway spruce stand in complex terrain
• 64. Steinhoff, Tobias: Uncertainty analysis for calculations of the marine carbonate system
• 68. Lindauer, Matthias: Vertical gradients of greenhouse gases at 8 German atmospheric ICOS Stations
• 84. Karstens, Ute: Assessment of regional atmospheric transport model performance using ²²²Radon observations
• 94. Klosterhalfen, Anne: Two-level Eddy Covariance Measurements Improve Land-atmosphere Flux Exchange Estimates over a Heterogeneous Boreal Forest Landscape
• 96. Skjelvan, Ingunn: Use of the unmanned surface vehicle Saildrone to validate Fixed Ocean Stations - the ATL2MED mission
• 118. Schibig, Michael F.: ICOS flask sampler performance tests
• 129. Kumar, Pramod: Local-scale atmospheric inversion for the estimation of the location and rate of CH4 and CO2 controlled releases using mobile and fixed-point measurements
• 134. Theetaert, Hannelore: Surface water CO₂ measurements in the North Atlantic Ocean: optimize methodologies and analytical procedures.
• 170. Brunner, Dominik: Atmospheric transport model analysis of methane emissions from oil- and gas-production in Romania observed during the ROMEO campaign in 2019
• 175. Raznjevic, Anja: Comparison of large eddy simulation of a point source methane plume in a slightly convective atmosphere with measurements from MEMO² campaign
• 178. Morales, Randulph: Spatio-temporal kriging in estimating local methane sources from drone-based laser spectrometer measurements
• 183. Kruijt, Bart: Towards operational quantification of GHG exchange in heterogeneous agricultural landscapes and experimental plots

Poster presentations in Theme 4

• 11. Walter, Sylvia: MEMO²: MEthane goes MObile – MEasurements and Modelling
• 29. Emmenegger, Lukas: High accuracy position tracking of drone flights with low-cost RTK-GPS
• 31. Vaidya, Shrijana: A novel robotic chamber system allowing to accurately and precisely determining spatio-temporal CO₂ flux dynamics of heterogeneous croplands
• 101. Shabaz, Muhammad: Measuring isotopic N₂O, CO₂ and CH₄ soil flux with Cavity Ring-Down Spectrometer for soil flux measurements
• 119. László, Haszpra: Technical note on tall-tower measurement strategy
• 137. Andersen, Truls: Quantifying methane emissions from coal mining ventilation shafts using a small Unmanned Aerial Vehicle (UAV)- based system
• 167. Defratyka, Sara: Characterization of natural gas compressor stations in Ile-de-France regions: CH4 emission rate, C2H6: CH4 ratio, and isotopic signatures
• 174. Pfeil, Benjamin: Handling marine carbon data from raw data to data products in respect to the Sustainable Development Goals and the FAIR Data Management Principles
• 193. Burgemeister, Finn: Comparisons of wind tunnel tests and field measurements for different sonic sensor head geometries ◄ 
• 196. Korben, Piotr: Quantification of methane emission from oil and gas wells using Other Test Method 33a during ROMEO campaign
• 207. Zhao, Junbin: Gap-filling continuously-measured flux data: a highlight of time-series-based methods
• 213. O'Neill, Macdara: From leaf to ecosystem: seasonal CO₂ exchange over a winter oilseed rape crop

Conveners: Pete Smith, Are Olsen, Jean-François Soussana, Gregor Rehder, Luca Montanarella, Ivan Janssens, Cristina Arias-Navarro

The rise of atmospheric concentrations of carbon dioxide due to anthropogenic forcing is partly mitigated by the uptake and storage on land and in the ocean. The various parts of the land and ocean carbon sinks store carbon on very different timescales. The storage time scales at the points of uptake, e.g. the sea surface or terrestrial above-ground biomass, are seasonal to annual, or even shorter. Long-term removal of carbon from the atmosphere thus requires transfer of the carbon to a reservoir that is stable on timescales of centuries, millennia or more (sub-soil layers, deep-ocean, lithosphere). Ocean mixing, export production, organic matter burial and decomposition and soil respiration are among the processes related to the carbon cycle. The magnitude of these, typically vertical fluxes between carbon reservoirs both on land and in the ocean, are much less constrained than the surface fluxes (air-sea fluxes, net ecosystem exchange).

Closely related is the call for better managing long-term carbon reservoirs to contribute to climate change mitigation and to enhance resilience to climate change. This addresses in particular the management of soils to increase soil organic carbon (SOC) content, which would also underpin food security. This is a subject of growing international interest through initiatives such as the international ‘4p1000’ initiative and the FAO's Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading, including  (1) Long term experiments (2) Short term experiments (3) SOC / GHG models (4) Spatial data to drive models (5) Activity data (6) Remote sensing (7) Spatial soil re-sampling surveys. A soil carbon monitoring system will require a strong collaboration between EC JRC, Copernicus, GEOSS (Group on Earth Observations), ICOS (Integrated Carbon Observation System), GSP (Global Soil Partnership), long-term soil studies and the integration of agricultural activities data into a global framework. In this way, the implications of projects contributing to SOC sequestration will be monitored, reported and verified at local, national and global scales through the same internationally shared monitoring system.
 
We invite presentations addressing the transfer of carbon from reservoirs that interact with the atmosphere on short time scales to reservoirs that will isolate the carbon for centuries or more. Contributions on both land and ocean sink as well as those addressing the different components for a MRV system of SOC change are welcome. Presentations from all thematic components of ICOS are encouraged.

Plenary presentations in Theme 5

• 190. Wanninkhof, Richard: Products from a surface ocean CO2 reference network, SOCONET

Oral presentations in Theme 5

Part of Session 16.

• 18. Leseurre, Coraline: CO₂ increase and ocean acidification in the Southern Indian Ocean over the last two decades
• 26. Macovei, Vlad: Long-term intercomparison of two pCO₂ instruments based on ship-of-opportunity measurements in the Skagerrak
• 75. Althuizen, Inge: Annual ecosystem carbon budgets across an abrupt permafrost thaw gradient in Northern Norway
• 113. Fer, Istem: Operational decision tools for climate change mitigation: a case study for agricultural systems
• 142. Davila, Xabier: How is the Ocean Anthropogenic Reservoir Filled?

Poster presentations in Theme 5

• 14. Mamkin, Vadim: Ecosystem СО₂ fluxes in an undisturbed mature spruce forest and adjacent clear-cut in southern taiga of European Russia
• 135. Grünwald, Thomas: Greenhouse Gas Emissions from two Reservoirs in East Germany: Mechanisms and Quantification
• 168. Tong, Cheuk Hei Marcus: The net ecosystem carbon balance of a nutrient-poor drained peatland forest in boreal Sweden
• 211. Lange, Holger: Dynamics of carbon fluxes at different temporal scales for a youg spruce plantation

Conveners: Christian Rödenbeck, Ingrid Luijkx, Ute Karstens, Peter Landschützer

The response of the natural carbon cycle on land and ocean to environmental changes co-determines the future climate trajectory.

Sustained measurements of CO2 in the atmosphere and the ocean, collected by the extensive observational efforts within ICOS and at various institutions worldwide, have been providing a basis to quantify and understand CO2 fluxes and their relationships to climate. Additional information is provided by measurements of related tracers (isotopic ratios, COS, APO, Ar, nutrients, etc.). Traditional data-based estimation methods, such as atmospheric transport inversions, surface-ocean interpolations, etc., are being developed further to make use of the information in the multiple observational records.

The session invites presentations around data-driven estimates of the global or regional carbon cycle, its variability, its responses to climate anomalies and trends, and process attribution.

Depending on the interest from the community (TransCom, SOCOM, etc.), the results-oriented session will be accompanied by discussion workshops as side events before or after the main conference program, to discuss innovative methodological developments and/or community activities around data-driven carbon cycle estimates.

Subtheme 6.2: Using the ICOS network as anchor stations for investigating fluxes of reactive gases and aerosols in terrestrial ecosystems

Conveners: Christian Brümmer, Silvano Fares

Reactive gases and aerosols play a major role in atmospheric chemistry and may act as important nutrient inputs for terrestrial ecosystems. The ICOS network offers the opportunity to complement common observations of greenhouse gases with measurements of reactive gas fluxes between plant ecosystems and the atmosphere. Plant ecosystems exchange reactive trace gases, such as nitrogen oxides (NOx), ozone, and volatile organic compounds (VOCs), and particles. While some of these compounds are anthropogenically produced, many are biotic in origin and are emitted in-situ or produced from rapid photochemistry in the canopy. The oxidation products include low-volatility organic compounds that readily partition to the aerosol phase, particularly in the presence of anthropogenic pollutants such as ammonium, nitrate and sulphate.

In addition to being strong sources, soil and leaves represent major sinks of these reaction products, with deposition to the surface also as a function of surface wetness and uptake into the leaf via the stomata. The canopy region thus represents a dynamic and rapidly changing environment in which a myriad biological, chemical and physical processes occur over very short time and spatial scales. Advanced techniques of flux measurements provide good knowledge of the overall net fluxes of these compounds above canopies, while additional in-canopy measurements enable more detailed study and understanding of the individual processes and reactions driving these fluxes. These rapidly advancing measurements can support parametrization of models for a mechanistic understanding of in-canopy dynamics of deposition and emission of these reactive gases, which can in turn allow fuller interpretation of in-situ measurements and inform the design of field experiments to test specific hypotheses. This session, sponsored by ILEAPS (Integrated Land Ecosystem Atmosphere Process Study), encourages the submission of contributions based on in-situ measurements and/or modeling that improve our understanding of biosphere-atmosphere exchange of reactive gases and aerosols and in-canopy processes.

Subtheme 6.3: Towards more constrained methane budgets

Conveners: Annalea Lohila, Tuula Aalto

Increased atmospheric concentration of methane (CH4) is a major determinant of global warming. CH4 is being emitted into the atmosphere from both natural and anthropogenic sources, from the latter at a growing rate. While the increase in CH4 concentration slowed down in the beginning of the 2000’s and stayed stable for 6-7 years after that, we are now witnessing a new era of even more rapidly growing concentrations. The reasons for these changes are not fully understood. Also, the global CH4 budget still has considerable uncertainties, particularly regarding biogenic emissions. For example, the role of inland waters and wetlands remains uncertain. Better process understanding is needed in order to make reliable projections for the future CH4 emissions. In this session, we welcome contributions from different fields of research, such as flux and process studies, utilization of measurement networks and infrastructures, application of multiple tracers and isotopes, climate and ecosystem modelling, and the use of atmospheric data in inverse modelling.

Plenary presentations in Theme 6

• 152. Gerbig, Christoph: Can we see a covid-19 impact in atmospheric GHGs? A diagnostic assessment using STILT

Oral presentations in Theme 6

Part of Session 6, Session 12, and Session 18.

• 30. Dong, Yuanxu: Factors affecting the air-sea CO2 flux in the Arctic Ocean in summer
• 39. Schrader, Frederik: Research infrastructures as modular platforms for reactive nitrogen deposition monitoring
• 40. Ma, Jin: Inverse modelling of global carbonyl sulfide budget using TM5-4DVAR and model validation
• 61. Bukosa, Beata: CarbonWatchNZ: Regional to National Scale Inverse Modelling of New Zealand’s Carbon Balance
• 72. Pieber, Simone: Simulations of atmospheric CO₂ and δ¹³C-CO₂ compared to real-time observations at the high altitude station Jungfraujoch
• 78. Watson, Andrew: Substantially larger estimates of global ocean-atmosphere fluxes of atmospheric CO₂ from surface data obtained when temperature corrections are applied
• 81. Kooijmans, Linda: Validation and development of carbonyl sulfide biosphere exchange in the Simple Biosphere Model (SiB4)
• 87. Bakker, Dorothee C. E.: The value chain of ocean CO2 measurements
• 89. Zweifel, Roman: Variability in annual tree growth – how much determination of the past is in the present response?
• 95. Skeie, Ragnhild: Recent trends in sources and sinks of methane
• 100. Kangasaho, Vilma: Modelling seasonal cycle of atmospheric δ¹³C-CH₄ and their evaluations with δ¹³C-CH₄ observations
• 159. Aki, Tsuruta: Spatial and temporal distribution of European CH₄ emissions from process-based models and CTE-CH₄ atmospheric inverse model
• 162. Kohonen, Kukka-Maaria: Environmental drivers of GPP derived from CO₂, COS and SIF measurements
• 202. Koren, Gerbrand: Resolving the diurnal cycle of Δ¹⁷O in CO₂ at the ecosystem level: Simulations and observations at the mid-latitude pine forest Loobos
• 203. Krol, Maarten: COS-OCS: Carbonyl Sulfide, new ways of Observing the Climate System

Poster presentations in Theme 6

• 12. Nadiradze, Kakha: Adaptation and mitigation Climate change and environmental degradation processes affecting all types of Agricultural activities
• 32. Luijkx, Ingrid: Atmospheric O₂ and CO₂ exchange in a boreal forest in Hyytiälä, Finland
• 42. Zhang, Shuping: Remote sensing supported sea surface pCO2 estimation and variable analysis in the Baltic Sea
• 57. Lefevre, Nathalie: Impact of Amazon propagation on the air-sea flux of CO₂ from model and observations
• 58. Bignotti, Laura: Aerosol gradients and fluxes in a mixed oak-hornbeam forest
• 65. Wang, Hengmao: Regional Terrestrial Ecosystem Carbon Flux Constrained with New Ground CO2 Observations in China
• 73. Cho, Ara: Coupled chemical transport model-Biosphere model for a better understanding of CO2 and COS budgets
• 85. Tong, Xin: Nocturnal surface fluxes of N₂O and CH₄ determined from atmospheric measurements at the Cabauw tall tower
• 92. Gupta, Aniket: Modeling the atmospheric fluxes in a sub-alpine critical zone monitoring network, Col du Lautaret, French Alps
• 93. Moreaux, Virginie: Can we see it? How in situ observation networks may detect environmental impacts on ecosystem biogeochemistry.
• 111. Wintjen, Pascal: Forest-atmosphere exchange of reactive nitrogen in a low polluted mountain range - temporal dynamics and annual budgets
• 114. Galkowski, Michal: Improving estimates of emissions of methane and carbon dioxide from strong emission region using analytical inversion system coupled with WRF-GHG tagged tracer simulations
• 121. Yeon, Bae: Evaluating the effect of the urban forest on the flux of reactive gases and aerosols in the atmosphere using WRF-CMAQ model
• 128. Sauzedde, Elisa: A Case study on early snowmelt and its influence on seasonal carbon uptake in an alpine meadow (Col du Lautaret)
• 132. Chierici, Melissa: Ocean carbon exchange and drivers from winter to summer in the Atlantic water inflow to the Arctic Ocean
• 133. Lelandais, Ludovic: In-situ continuous atmospheric greenhouse gases (CO₂, CH₄ and CO) measurements at the OHP ICOS-Fr station tall tower in South France from July 2014 to March 2020 and related anthropogenic tracers.
• 150. Menoud, Malika: Characterisation of methane sources in Krakow, Poland, using high temporal resolution isotopic composition measurements
• 154. Tenkanen, Maria: Utilizing Remote Sensing of the Soil Freeze/Thaw State to Estimate Cold Season Methane Emissions in the Northern Hemisphere
• 153. Bastos Campos, Flávio: Biological and physical controls on Water Use Efficiency across contrasting ecosystems in the alpine region
• 169. García-Ibáñez, Maribel I.: Carbon uptake by Subantarctic Pacific waters
• 177. Miller, Scot: A comparison of recent trends in methane emissions from China, the US, and Europe
• 186. Lakomiec, Patryk: Isotopic composition of methane from Swedish wetlands
• 191. Maazallahi, Hossein: CH₄ emissions from oil and gas productions in Romania; an analysis of emission inventory reports and measurement-based data from ROMEO campaign
• 197. Aalto, Tuula: Precipitation and temperature controls over wetland methane emissions estimated by atmospheric inversion modeling
• 209. Trisolino, Pamela: 5-year analysis of near-surface atmospheric CO2 in Italy by a collaborative network of four permanent observatories

Conveners: Erik Andersson, Huilin Chen, Greet Maenhout, Bruna RF Oliveira, Jan Pisek, Marko Scholze, Mahesh Kumar Sha, Thorsten Warneke

Greenhouse gases (GHG) in the atmosphere have been on the continuous rise since the industrialization. Both remote sensing and in situ atmospheric observations of greenhouse gases (GHGs) are increasingly available, and are essential for estimating surface fluxes of GHGs at from local to regional and continental scales. The remote sensing measurement has the advantage of providing information of GHG concentrations in an integrated path, either a vertical column or a horizontal path, and may provide a good spatial coverage when deployed on aircraft and satellites. The remote sensing measurements are useful to infer surface fluxes and to identify and quantify hot spot emissions of CO2 and CH4, although such applications are limited by the relatively large uncertainties, especially when compared to in situ measurements. On the other hand, in situ measurements can be made accurate with improved analytical techniques and available direct calibrations, but are either temporal or spatial limited. To this end, a combination of remote sensing and in situ measurements is naturally preferred.

Ground-based solar absorption measurements of absorption of solar radiation are an important component in the global observing system. The Total Carbon Column Observing Network (TCCON) is the reference network for the validation of greenhouse gas retrievals from satellites and mobile spectrometers within the Collaborative Carbon Column Observing Network (COCCON) complement TCCON and are used for emission measurements from cities. Several satellite missions for atmospheric greenhouse gas measurements are scheduled for launch in the coming decade. Therefore, it can be expected that remote sensing measurements will become increasingly important for carbon cycle research.

The European Commission together with the European space and weather organizations are establishing a Copernicus CO2 Monitoring & Verification Support (MVS) capacity in support of the Paris Agreement. Such a CO2 MVS capacity requires multiple in-situ data as described in the Green CO2 Report.).

Ecosystems respond to changing environmental conditions with various biogeochemical reactions that influence the remote sensing signal. Advances in Earth observation technologies offer opportunities to understand ecosystem structure and function across various spatial and temporal scales. Remote sensing observations allow researchers to link trends in vegetative traitswith key ecosystem processes. Novel, cross-disciplinary approaches, integrating remote sensing with in situ and experimental measurements, can help improve the monitoring and management of ecosystem changes over time and increase the accuracy of ecosystem models.

Besides showcasing the recent advances, this theme also aims to highlight the associated challenges: What are the options for tackling the scaling gap between field and satellite measurements? How to address the temporal gap and scale up from daily observations to seasonal trends? What are the best practices to establish data quality through traceability, uncertainty, and validation? How can we separate fossil-fuel emissions from natural sources? How can ICOS contribute to tackle these challenges?

We invite presentations addressing: (1) remote sensing techniques for monitoring greenhouse gases from ground-based instrumentations; (2) Integration of long-term and campaign-based in situ and remote sensing measurements; (3) application of these measurements, such as in-situ data in support of the CO2 MVS capacity.  This session will include observations from satellite, TCCON, AirCore, aircraft, drones, and ICOS stations.  In particular the session focuses on the benefit of in-situ data in the presence of remotely sensed CO2 (such as from CO2M) and CH4 concentrations as well as the requirements on the in situ networks (station density, measurement accuracy, type of instrument). This interdisciplinary session will highlight an array of experimental, observational, and modelling studies as well as the pitfalls in using Earth observation data to address these challenges.

Plenary presentations in Theme 7

• 108. Sha Mahesh, Kumar: Measurements of greenhouse gases from ground-based remote sensing and in-situ instruments and their application for satellite validation

Oral presentations in Theme 7

Part of Session 5 and Session 11.

• 52. Pisek, Jan: Plausibility, validation and intercomparison of clumping index products from MISR, MODIS, POLDER, and DSCOVR EPIC EARTH observation data over European ICOS RI forest ecosystem sites
• 74. Scholze, Marko: Assessments of in situ and remotely sensed CO₂ observations in a Carbon Cycle Fossil Fuel Data Assimilation System to estimate fossil fuel emissions
• 79. Demol, Miro: Terrestrial laser scanning, the future of forest mensuration at ICOS
• 138. Chen, Huilin: Comparisons of AirCore vertical profiles of greenhouse gases from an intensive RINGO campaign at Sodankylä, Finland ◄ 
• 155. Lamminpää, Otto: Satellite-based analysis on linking photosynthetic activity to different land cover types
• 180. Henne, Stephan: Simulating CO₂ plumes from power plants at (sub-)kilometer-scale and consequences for satellite-based CO₂ emission monitoring
• 181. Aben, Ilse: Using satellite observations to detect and quantify concentrated methane emissions
• 182. Karppinen, Tomi: Vertical Distribution of Arctic Methane in 2009–2018 Using Ground-Based Remote Sensing
• 194. Baier, Bianca: Towards greenhouse gas remote sensing evaluation using the AirCore atmospheric sampling system
• 210. Humpage, Neil: Greenhouse gas column observations from a portable spectrometer in tropical Africa

Poster presentations in Theme 7

• 13. Yurganov, Leonid: Variations in seawater mixing and ice concentration as main drivers for changes in methane over the Arctic seas: satellite data.
• 80. Weidmann, Damien: Large area GHG monitoring in all weather conditions: a new tool for ground truthing
• 97. Kivi, Rigel: Remote sensing and in situ measurements of greenhouse gases at Sodankylä, Finland
• 161. Raj, Rahul: Evaluating time series of leaf chlorophyll content prediction from multispectral remote sensing data
• 206. Zhou, Minqiang: CH4 profile retrieval from ground-based FTIR near-infrared spectra

Conveners: Janne-Markus Rintala, Syed Ashraful Alam, Elena Saltikoff

The rapid developments due to digitalisation, globalisation and climate change are huge challenges that people are already facing. The young suffering from climate anxiety are not the only ones hungry for learning more about climate and greenhouse gases. A life-long learning entails everyone in a modern society.

ICOS data is made available to everyone. Yet its efficient use requires basic skills of i.e. the Jupiter notebook, R, Matlab etc. Student engagement using this data including educators with sparking ideas for teaching including on-line training tools, organizing of MOOC-courses, gamification and other novel ideas and techniques everyone can use to disseminate their results and making their conclusions widely known to create a societal impact needed to make necessary change in our behavior to save the planet.

Plenary presentations in Theme 8

• 148. Pantazatou, Karolina: Presenting ICOS data in education

Oral presentations in Theme 8

Part of Session 13.

• 91. Steinbacher, Martin: The importance of training for long-term operation of atmospheric greenhouse gas observations
• 104. Riuttanen, Laura: Learning multidisciplinary climate change competencies
• 172. Storm, Ida: ICOS atmosphere station characterization tool
• 185. D'Onofrio, Claudio: ICOS Data at Your Fingertips

Poster presentations in Theme 8

• (Nil.)

Oral presentations in the Extra Theme

Part of Session 2.

• 33. Ciais, Philippe: COVID-19 causes record decline in global CO2 emissions
• 46. Politakos, Konstantinos: Inter-annual variability of Eddy Covariance CO₂ flux measurements in the city center of Heraklion, Greece
• 131. Hoheisel, Antje: Comparison of atmospheric CO, CO₂ and CH₄ measurements at Schneefernerhaus and the mountain ridge at Zugspitze, Germany
• 192. Ramonet, Michel: Pollution events, heatwaves, COVID lockdowns: what do we see in our recent atmospheric CO2, CH4, N2O observations in France?
• 82. Emmenegger, Lukas: Observation of urban CO₂ emissions using spatially dense low-cost sensing and modelling

Poster presentations in the Extra Theme

• 27. Mihalopoulos, Nikolaos: Greenhouse gases measurements at the urban environment of Athens, Greece
• 47. Xueref-Remy, Irène: Assessing the impact of the Spring 2020 COVID-19 lockdown on atmospheric CO2 concentration in the Aix-Marseille area, France.
• 112. Schibig, Michael F.: Influence of SARS-CoV-2 lockdown on atmospheric background CO₂ values measured at the High Altitude Research Station Jungfraujoch, Switzerland