Yutaka Matsumi

Bio: Yutaka Matsumi is an academic researcher from Nagoya University. The author has contributed to research in topics: Photodissociation & Laser-induced fluorescence. The author has an hindex of 37, co-authored 215 publications receiving 4730 citations. Previous affiliations of Yutaka Matsumi include Hokkaido University & University of Southern Denmark.

Continuous measurements of stable isotopes of carbon dioxide and water vapour in an urban atmosphere: isotopic variations associated with meteorological conditions.

Abstract: Isotope ratios of carbon dioxide and water vapour in the near-surface air were continuously measured for one month in an urban area of the city of Nagoya in central Japan in September 2010 using laser spectroscopic techniques. During the passages of a typhoon and a stationary front in the observation period, remarkable changes in the isotope ratios of CO2 and water vapour were observed. The isotope ratios of both CO2 and water vapour decreased during the typhoon passage. The decreases can be attributed to the air coming from an industrial area and the rainout effects of the typhoon, respectively. During the passage of the stationary front, δ13C–CO2 and δ18O–CO2 increased, while δ2H–H2Ov and δ18O–H2Ov decreased. These changes can be attributed to the air coming from rural areas and the air surrounding the observational site changing from a subtropical air mass to a subpolar air mass during the passage of the stationary front. A clear relationship was observed between the isotopic CO2 and water vapo...

Laboratory Study of O(1S) Formation Process in the Photolysis of O3 and its Atmospheric Implications

Abstract: A high-sensitive technique to detect O(1S) atoms using vacuum ultraviolet laser-induced fluorescence (VUV-LIF) spectroscopy has been applied to study the O(1S) production process from the UV photodissociation of O3, N2O, and H2O2. The quantum yields for O(1S) formation from O3 photolysis at 215 and 220 nm are determined to be (1.4 ± 0.4) × 10−4 and (5 ± 3) × 10−5, respectively. Based on thermochemical considerations, the O(1S) formation from O3 photolysis at 215 and 220 nm is attributed to a spin-forbidden process of O(1S)+O2(X3Σg −). Analysis of the Doppler profile of O(1S) produced from O3 photolysis at 193 nm also indicates that the O(1S) atoms are produced from the spin-forbidden process. In the photolysis of N2O and H2O2 at 193 nm, no discernible signal of O(1S) atoms has been detected. The upper limit values of the quantum yields for O(1S) production from N2O and H2O2 photolysis at 193 nm are estimated to be 8 × 10−5 and 3 × 10−5, respectively. Using the experimental results, the impact of the O(1S) formation from O3 photolysis on the atmospheric OH radical formation through the reaction of O(1S)+H2O has been estimated. The calculated results show that the contribution of the O(1S)+H2O reaction to the OH production rate is ∼2% of that of the O(1D)+H2O reaction at 30 km altitude in mid-latitude. Implications of the present laboratory experimental results for the terrestrial airglow of O(1S) at 557.7 nm have also been discussed.

Observation of vertical profiles of NO, O3, and VOCs to estimate their sources and sinks by inverse modeling in a Japanese larch forest

Abstract: Trace atmospheric gases in the biosphere, such as ozone (O3), nitrogen oxides (NOx), and biogenic volatile organic compounds (BVOCs), can affect the carbon cycle as well as the climate. Vertical profiles of nitric oxide (NO), O3, and volatile organic compound (VOC) concentrations were measured at a Japanese larch (Larix kaempferi) forest in the foothills of Mt. Fuji in Japan over an 11-day period in July 2012. The concentrations of NO and O3 during the day were highest above the canopy and decreased with proximity to the forest floor, but those of the VOCs had minimum and maximum points at different levels within the canopy depending on the species. Inverse multilayer models were applied to identify vertical sink and source distribution of these gases within the canopy. The model estimated that there was higher O3 deposition and absorption at the forest floor than in the canopy layer; therefore, the understory was an important O3 sink within the forest. A strong NO sink was simulated in the trunk space, where loss by reaction with O3 is expected. The sinks and sources of BVOC as well as their oxidized products are simulated in the canopy layer and the forest floor. The sink and source distribution suggested that VOC transportation from the neighboring forest also affected the vertical sink and source distribution within the canopy.

Velocity map imaging of ions and electrons using electrostatic lenses: Application in photoelectron and photofragment ion imaging of molecular oxygen

Abstract: The application of electrostatic lenses is demonstrated to give a substantial improvement of the two-dimensional (2D) ion/electron imaging technique. This combination of ion lens optics and 2D detection makes “velocity map imaging” possible, i.e., all particles with the same initial velocity vector are mapped onto the same point on the detector. Whereas the more common application of grid electrodes leads to transmission reduction, severe trajectory deflections and blurring due to the non-point source geometry, these problems are avoided with open lens electrodes. A three-plate assembly with aperture electrodes has been tested and its properties are compared with those of grid electrodes. The photodissociation processes occurring in molecular oxygen following the two-photon 3dπ(3Σ1g −)(v=2, N=2)←X(3Σg −) Rydberg excitation around 225 nm are presented here to show the improvement in spatial resolution in the ion and electron images. Simulated trajectory calculations show good agreement with experiment and ...

Perfluoroalkyl and polyfluoroalkyl substances in the environment: Terminology, classification, and origins

Abstract: The primary aim of this article is to provide an overview of perfluoroalkyl and polyfluoroalkyl substances (PFASs) detected in the environment, wildlife, and humans, and recommend clear, specific, and descriptive terminology, names, and acronyms for PFASs. The overarching objective is to unify and harmonize communication on PFASs by offering terminology for use by the global scientific, regulatory, and industrial communities. A particular emphasis is placed on long-chain perfluoroalkyl acids, substances related to the long-chain perfluoroalkyl acids, and substances intended as alternatives to the use of the long-chain perfluoroalkyl acids or their precursors. First, we define PFASs, classify them into various families, and recommend a pragmatic set of common names and acronyms for both the families and their individual members. Terminology related to fluorinated polymers is an important aspect of our classification. Second, we provide a brief description of the 2 main production processes, electrochemical fluorination and telomerization, used for introducing perfluoroalkyl moieties into organic compounds, and we specify the types of byproducts (isomers and homologues) likely to arise in these processes. Third, we show how the principal families of PFASs are interrelated as industrial, environmental, or metabolic precursors or transformation products of one another. We pay particular attention to those PFASs that have the potential to be converted, by abiotic or biotic environmental processes or by human metabolism, into long-chain perfluoroalkyl carboxylic or sulfonic acids, which are currently the focus of regulatory action. The Supplemental Data lists 42 families and subfamilies of PFASs and 268 selected individual compounds, providing recommended names and acronyms, and structural formulas, as well as Chemical Abstracts Service registry numbers. Integr Environ Assess Manag 2011;7:513–541. © 2011 SETAC

Couplings between changes in the climate system and biogeochemistry

Abstract: Couplings Between Changes in the Climate System and Biogeochemistry Coordinating Lead Authors: Kenneth L. Denman (Canada), Guy Brasseur (USA, Germany) Lead Authors: Amnat Chidthaisong (Thailand), Philippe Ciais (France), Peter M. Cox (UK), Robert E. Dickinson (USA), Didier Hauglustaine (France), Christoph Heinze (Norway, Germany), Elisabeth Holland (USA), Daniel Jacob (USA, France), Ulrike Lohmann (Switzerland), Srikanthan Ramachandran (India), Pedro Leite da Silva Dias (Brazil), Steven C. Wofsy (USA), Xiaoye Zhang (China) Contributing Authors: D. Archer (USA), V. Arora (Canada), J. Austin (USA), D. Baker (USA), J.A. Berry (USA), R. Betts (UK), G. Bonan (USA), P. Bousquet (France), J. Canadell (Australia), J. Christian (Canada), D.A. Clark (USA), M. Dameris (Germany), F. Dentener (EU), D. Easterling (USA), V. Eyring (Germany), J. Feichter (Germany), P. Friedlingstein (France, Belgium), I. Fung (USA), S. Fuzzi (Italy), S. Gong (Canada), N. Gruber (USA, Switzerland), A. Guenther (USA), K. Gurney (USA), A. Henderson-Sellers (Switzerland), J. House (UK), A. Jones (UK), C. Jones (UK), B. Karcher (Germany), M. Kawamiya (Japan), K. Lassey (New Zealand), C. Le Quere (UK, France, Canada), C. Leck (Sweden), J. Lee-Taylor (USA, UK), Y. Malhi (UK), K. Masarie (USA), G. McFiggans (UK), S. Menon (USA), J.B. Miller (USA), P. Peylin (France), A. Pitman (Australia), J. Quaas (Germany), M. Raupach (Australia), P. Rayner (France), G. Rehder (Germany), U. Riebesell (Germany), C. Rodenbeck (Germany), L. Rotstayn (Australia), N. Roulet (Canada), C. Sabine (USA), M.G. Schultz (Germany), M. Schulz (France, Germany), S.E. Schwartz (USA), W. Steffen (Australia), D. Stevenson (UK), Y. Tian (USA, China), K.E. Trenberth (USA), T. Van Noije (Netherlands), O. Wild (Japan, UK), T. Zhang (USA, China), L. Zhou (USA, China) Review Editors: Kansri Boonpragob (Thailand), Martin Heimann (Germany, Switzerland), Mario Molina (USA, Mexico) This chapter should be cited as: Denman, K.L., G. Brasseur, A. Chidthaisong, P. Ciais, P.M. Cox, R.E. Dickinson, D. Hauglustaine, C. Heinze, E. Holland, D. Jacob, U. Lohmann, S Ramachandran, P.L. da Silva Dias, S.C. Wofsy and X. Zhang, 2007: Couplings Between Changes in the Climate System and Biogeochemistry. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.