Reconciling the Carbon Balance of Northern Sweden Through Integration of Observations and Modelling

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Sathyanadh, Anusha, Monteil, Guillaume, Scholze, Marko, Klosterhalfen, Anne, Laudon, Hjalmar, Wu, Zhendong, Gerbig, Christoph, Peters, Wouter, Bastrikov, Vladislav, Nilsson, Mats B., Peichl, Matthias
• Other Authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), European Commission, EC; Svenska Forskningsrådet Formas; National Science Council, NSC: 2018‐05973; Vetenskapsrådet, VR; Kempestiftelserna: 942‐2015‐49, JCK‐1815, The first author, Anusha Sathyanadh, acknowledges a Postdoctoral Scholarship funded by the Kempe Foundations (grant no: JCK-1815). A grant (no. 942-2015-49) from the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) funded the tall tower eddy covariance measurements at Svartberget. Financial support from the Swedish Research Council and research institutes contributing to the Swedish Integrated Carbon Observation System (ICOS-Sweden) and Research Infrastructure from the Swedish Infrastructure for Ecosystem Science (SITES) is also acknowledged. Marko Scholze and Guillaume Monteil acknowledge support from the three Swedish strategic research areas ModElling the Regional and Global earth system (MERGE), the e-science collaboration (eSSENCE), and Biodiversity and Ecosystems in a Changing Climate (BECC). The computations were enabled with resources provided by the Swedish National Infrastructure for Computing (SNIC) at NSC partially funded by the Swedish Research Council through grant agreement no. 2018-05973. We thank Greet Janssens-Meanhout (European Commission, Joint Research Center, 790 Ispra, Italy) for providing the fuel type and category specific version of the EDGAR v4.3 anthropogenic emission data and Hugo Denier van der Gon (TNO, The Netherlands) for making the temporal emission profiles available. We also thank the PIs of the atmospheric stations at ICOS Svartberget, Norunda, Hyltemossa, Puijo, Pallas, and Hyytiala (SE-SVB, SE-NOR, SE-HTM, FI-PUI, FI-PAL, and FI-SMR) for providing data on atmospheric CO2 concentrations. The authors thank the staff at the SLU Unit for Field-Based Forest Research for technical and logistic support at the Svartberget station., The first author, Anusha Sathyanadh, acknowledges a Postdoctoral Scholarship funded by the Kempe Foundations (grant no: JCK‐1815). A grant (no. 942‐2015‐49) from the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) funded the tall tower eddy covariance measurements at Svartberget. Financial support from the Swedish Research Council and research institutes contributing to the Swedish Integrated Carbon Observation System (ICOS‐Sweden) and Research Infrastructure from the Swedish Infrastructure for Ecosystem Science (SITES) is also acknowledged. Marko Scholze and Guillaume Monteil acknowledge support from the three Swedish strategic research areas ModElling the Regional and Global earth system (MERGE), the e‐science collaboration (eSSENCE), and Biodiversity and Ecosystems in a Changing Climate (BECC). The computations were enabled with resources provided by the Swedish National Infrastructure for Computing (SNIC) at NSC partially funded by the Swedish Research Council through grant agreement no. 2018‐05973. We thank Greet Janssens‐Meanhout (European Commission, Joint Research Center, 790 Ispra, Italy) for providing the fuel type and category specific version of the EDGAR v4.3 anthropogenic emission data and Hugo Denier van der Gon (TNO, The Netherlands) for making the temporal emission profiles available. We also thank the PIs of the atmospheric stations at ICOS Svartberget, Norunda, Hyltemossa, Puijo, Pallas, and Hyytiala (SE‐SVB, SE‐NOR, SE‐HTM, FI‐PUI, FI‐PAL, and FI‐SMR) for providing data on atmospheric CO concentrations. The authors thank the staff at the SLU Unit for Field‐Based Forest Research for technical and logistic support at the Svartberget station. 2
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: vegetation model; tall tower eddy covariance; net ecosystem exchange; FLEXPART; boreal biome; atmospheric transport model; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Northern Sweden
• Online Access: https://hal.archives-ouvertes.fr/hal-03487722; https://doi.org/10.1029/2021JD035185

International audience The boreal biome plays an important role in the global carbon cycle. However, current estimates of its sink-source strength and responses to changes in climate are primarily derived from models and thus remain uncertain. A major challenge is the validation of these models at a regional scale since empirical flux estimates are typically confined to ecosystem or continental scales. The Integrated Carbon Observation System (ICOS)-Svartberget atmospheric station (SVB) provides observations including tall tower eddy covariance (EC) and atmospheric concentration measurements that can contribute to such validation in Northern Sweden. Thus, the overall aim of this study was to quantify the carbon balance in Northern Sweden region by integrating land-atmosphere fluxes and atmospheric carbon dioxide (CO2) concentrations. There were three specific objectives. First, to compare flux estimates from four models (VPRM, LPJ-GUESS, ORCHIDEE, and SiBCASA) to tall tower EC measurements at SVB during the years 2016–2018. Second to assess the fluxes' impact on atmospheric CO2 concentrations using a regional transport model. Third, to assess the impact of the drought in 2018. The comparison of estimated concentrations with ICOS observations helped the evaluation of the models' regional scale performance. Both the simulations and observations indicate there were similar reductions in the net CO2 uptake during drought. All the models (except for SiBCASA) and observations indicated the region was a net carbon sink during the 3-year study period. Our study highlights a need to improve vegetation models through comparisons with empirical data and demonstrate the ICOS network's potential utility for constraining CO2 fluxes in the region.