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Challenges in quantifying biosphere-atmosphere exchange of nitrogen species
2007
Sutton, M.A. | Nemitz, E. | Erisman, J.W | Beier, C. | Butterbach Bahl, K. | Cellier, Pierre | de Vries, W. | Cotrufo, F. | Skiba, U | Di Marco, C. | Jones, S. | Laville, Patricia | Soussana, Jean-François | Loubet, Benjamin | Twigg, M. | Famulari, D. | Whitehead, J. | Gallagher, M.W. | Neftel, A. | Flechard, C.R. | Herrmann, B. | Calanca, P.L. | Schjoerring, J.K. | Daemmgen, U. | Horvath, L. | Tang, Y.P. | Emmett, B.A. | Tietema, A. | Penuelas, J. | Kesik, M. | Brueggemann, N. | Pilegaard, K. | Vesala, T. | Campbell, C.L. | Olesen, J.E. | Dragosits, U. | Theobald, M.R. | Levy, P. | Mobbs, D.C. | Milne, R. | Viovy, N. | Vuichard, N. | Smith, J.U. | Smith, P. | Bergamaschi, P. | Fowler, D. | Reis, S. | Centre for Ecology and Hydrology | Clean Fossil Fuels ; Energy Research Centre of the Netherlands (ECN) | Risø National Laboratory ; Danish Ministry of Science, Technology and Innovation | Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung (IMK-IFU) ; Karlsruher Institut für Technologie (KIT) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Wageningen University and Research [Wageningen] (WUR) | Seconda Università degli Studi di Napoli = Second University of Naples | Unité de recherche Agronomie de Clermont (URAC) ; Institut National de la Recherche Agronomique (INRA) | University of Manchester [Manchester] | Agroscope | Royal Veterinary and Agricultural University = Kongelige Veterinær- og Landbohøjskole (KVL ) | Institut für Agrarekologie | Hungarian Meteorological Service (OMSZ) | Centre for Ecology and Hydrology [Bangor] (CEH) ; Natural Environment Research Council (NERC) | University of Amsterdam [Amsterdam] (UvA) | Center for Ecolological Research and Forestry Applications | Helsingin yliopisto = Helsingfors universitet = University of Helsinki | Danish Institute of Agricultural Sciences | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Modélisation des Surfaces et Interfaces Continentales (MOSAIC) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | University of Aberdeen | JRC Institute for Environment and Sustainability (IES) ; European Commission - Joint Research Centre [Ispra] (JRC)
Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N2 fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N2O, NO and bi-directional NH3 exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols
Afficher plus [+] Moins [-]Challenges in quantifying biosphere-atmosphere exchange of nitrogen species
2007
Sutton, M.A. | Nemitz, E. | Erisman, J.W | Beier, C. | Butterbach Bahl, K. | Cellier, Pierre | de Vries, W. | Cotrufo, F. | Skiba, U | Di Marco, C. | Jones, S. | Laville, Patricia | Soussana, Jean-François | Loubet, Benjamin | Twigg, M. | Famulari, D. | Whitehead, J. | Gallagher, M.W. | Neftel, A. | Flechard, C.R. | Herrmann, B. | Calanca, P.L. | Schjoerring, J.K. | Daemmgen, U. | Horvath, L. | Tang, Y.P. | Emmett, B.A. | Tietema, A. | Penuelas, J. | Kesik, M. | Brueggemann, N. | Pilegaard, K. | Vesala, T. | Campbell, C.L. | Olesen, J.E. | Dragosits, U. | Theobald, M.R. | Levy, P. | Mobbs, D.C. | Milne, R. | Viovy, N. | Vuichard, N. | Smith, J.U. | Smith, P. | Bergamaschi, P. | Fowler, D. | Reis, S. | Centre for Ecology and Hydrology | Clean Fossil Fuels ; Energy Research Centre of the Netherlands (ECN) | Risø National Laboratory ; Danish Ministry of Science, Technology and Innovation | Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung (IMK-IFU) ; Karlsruhe Institute of Technology = Karlsruher Institut für Technologie (KIT) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Wageningen University and Research [Wageningen] (WUR) | Seconda Università degli Studi di Napoli = Second University of Naples | Unité de recherche Agronomie de Clermont (URAC) ; Institut National de la Recherche Agronomique (INRA) | University of Manchester [Manchester] | Agroscope | Royal Veterinary and Agricultural University = Kongelige Veterinær- og Landbohøjskole (KVL ) | Institut für Agrarekologie | Hungarian Meteorological Service (OMSZ) | Centre for Ecology and Hydrology [Bangor] (CEH) ; Natural Environment Research Council (NERC) | University of Amsterdam [Amsterdam] = Universiteit van Amsterdam (UvA) | Center for Ecolological Research and Forestry Applications | Helsingin yliopisto = Helsingfors universitet = University of Helsinki | Danish Institute of Agricultural Sciences | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | Modélisation des Surfaces et Interfaces Continentales (MOSAIC) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | University of Aberdeen | JRC Institute for Environment and Sustainability (IES) ; European Commission - Joint Research Centre [Ispra] (JRC)
Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N2 fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N2O, NO and bi-directional NH3 exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols
Afficher plus [+] Moins [-]Comparison of micrometeorological and two-film estimates of air–water gas exchange for alpha-hexachlorocyclohexane in the Canadian archipelago
2012
Wong, Fiona | Jantunen, Liisa M. | Papakyriakou, Tim | Staebler, Ralf | Stern, Gary A. | Bidleman, Terry F.
The air–sea gas exchange of alpha-hexachlorocyclohexane (α-HCH) in the Canadian Arctic was estimated using a micrometeorological approach and the commonly used Whitman two-film model. Concurrent shipboard measurements of α-HCH in air at two heights (1 and 15 m) and in surface seawater were conducted during the Circumpolar Flaw Lead study in 2008. Sampling was carried out during eight events in the early summer time when open water was encountered. The micrometeorological technique employed the vertical gradient in air concentration and the wind speed to estimate the flux; results were corrected for atmospheric stability using the Monin–Obukhov stability parameter. The Whitman two-film model used the concentrations of α-HCH in surface seawater, in bulk air at 1 and 15 m above the surface, and the Henry’s law constant adjusted for temperature and salinity to derive the flux. Both approaches showed that the overall net flux of α-HCH was from water to air. Mean fluxes calculated using the micrometeorological technique ranged from −3.5 to 18 ng m−2 day−1 (mean 7.4), compared to 3.5 to 14 ng m−2 day−1 (mean 7.5) using the Whitman two-film model. Flux estimates for individual events agreed in direction and within a factor of two in magnitude for six of eight events. For two events, fluxes estimated by micrometeorology were zero or negative, while fluxes estimated with the two-film model were positive, and the reasons for these discrepancies are unclear. Improvements are needed to shorten air sampling times to ensure that stationarity of meteorological conditions is not compromised over the measurement periods. The micrometeorological technique could be particularly useful to estimate fluxes of organic chemicals over water in situations where no water samples are available.
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