Special issue |
Integrated Land Ecosystem-Atmosphere Processes Study (iLEAPS) (ACP/BG inter-journal SI)(ACP/BG inter-journal SI)
Editor(s): A. B. Guenther, P. Artaxo, L. Ganzeveld, H. P. Schmid, M. Kulmala, A. Neftel, A. Arneth, J. Pongratz, N. Saigusa, S. Seneviratne, and S. M. Noe
Special issue jointly organized between Atmospheric Chemistry and Physics and Biogeosciences
iLEAPS is the land-atmosphere core project of the International Geosphere-Biosphere Programme (IGBP). The scientific goal of iLEAPS is to provide understanding how interacting physical, chemical and biological processes transport and transform energy and matter through the land-atmosphere interface. Atmospheric Chemistry and Physics (ACP) and Biogeosciences (BG) have opened a joint special issue on iLEAPS-related science, and you are welcome to contribute by sending manuscripts on land-atmosphere interactions to this joint issue via either ACP or BG. All the articles will be listed on the special issue joint webpage. The Editors of this special issue include Alex Guenther, Paulo Artaxo, Laurens Ganzeveld, Pavel Kabat, Hans Peter Schmid, and Markku Kulmala.
We collected aerosol samples in a midlatitude forest in Wakayama, Japan and analyzed the organic tracers of various sources. We found that compounds originating from fungal spores contributed significantly to total organic aerosol mass. On the other hand, those from oxidation of biogenic volatile organic compounds, although they could not be ignored, had relatively smaller mass fractions.
Turbulence, aerosol growth and microphysics of hydrometeors in clouds are intimately coupled. A new modelling approach was applied to quantify this linkage. We study the interaction in the cloud area under transient, high supersaturation conditions, using direct numerical simulations. Analysing the effect of aerosol dynamics on the turbulent kinetic energy and on vertical velocity, we conclude that the presence of aerosol has an effect on vertical motion and tends to reduce downward velocity.
By combining a regional model and a box model, this study simulates new particle formation in Nanjing, China, when the air masses were affected by anthropogenic activities, biogenic emissions, or mixed ocean and continental sources. The simulations reveal that biogenic organic compounds play a vital role in growth of newly formed clusters. This novel combination of two models makes it possible to accomplish new particle formation simulation without direct measurements of all chemical species.
Simultaneous measurements of concentrations and above-canopy fluxes of isoprene and α-pinene in a forest, along with their oxidation products in aerosols, suggest that the inflow of anthropogenic precursors/aerosols enhanced the formation of both isoprene- and α-pinene-derived secondary organic aerosol (SOA) within the forest canopy even when the flux was low. We also emphasize the role of vegetation/soils near the forest floor as important sources of isoprene and α-pinene in the forest.
We examined the spatial variability of N2O emissions from a tea field in a wet season using 147 static chambers. The N2O fluxes for a 30-min snapshot ranged from -1.73 to 1,659.11 g N ha-1 d-1 (average flux of 102.24 g N ha-1d-1). Cokriging with NH4Nt and NO3Nt as covariables (r=0.74 and RMSE=1.18) outperformed ordinary kriging (r=0.18 and RMSE=1.74), regression kriging with the sample position as a predictor (r=0.49 and RMSE=1.55) and cokriging with SOCt as a covariable (r=0.58 and RMSE=1.44).
This study provides seasonal and inter annual variation of biogenic NO emission fluxes in a Sahelian rangeland in Mali, a region where intense NO emissions occur during the wet season. Emissions are related to their biogeochemical origin, to the quantity of biomass, to the quantity of livestock, which drive the N pool and N turnover in the soil. This study gives an insight in the different N inputs to the soil and in N production processes in the soil at the origin of the emission.
A.-M. Sundström, A. Nikandrova, K. Atlaskina, T. Nieminen, V. Vakkari, L. Laakso, J. P. Beukes, A. Arola, P. G. van Zyl, M. Josipovic, A. D. Venter, K. Jaars, J. J. Pienaar, S. Piketh, A. Wiedensohler, E. K. Chiloane, G. de Leeuw, and M. Kulmala
A. Virkkula, J. Levula, T. Pohja, P. P. Aalto, P. Keronen, S. Schobesberger, C. B. Clements, L. Pirjola, A.-J. Kieloaho, L. Kulmala, H. Aaltonen, J. Patokoski, J. Pumpanen, J. Rinne, T. Ruuskanen, M. Pihlatie, H. E. Manninen, V. Aaltonen, H. Junninen, T. Petäjä, J. Backman, M. Dal Maso, T. Nieminen, T. Olsson, T. Grönholm, J. Aalto, T. H. Virtanen, M. Kajos, V.-M. Kerminen, D. M. Schultz, J. Kukkonen, M. Sofiev, G. De Leeuw, J. Bäck, P. Hari, and M. Kulmala
G. Keppel-Aleks, P. O. Wennberg, R. A. Washenfelder, D. Wunch, T. Schneider, G. C. Toon, R. J. Andres, J.-F. Blavier, B. Connor, K. J. Davis, A. R. Desai, J. Messerschmidt, J. Notholt, C. M. Roehl, V. Sherlock, B. B. Stephens, S. A. Vay, and S. C. Wofsy