Instrument: Ground based FTIR

Principal Investigator: Makoto Koike

Co-Investigator: Yutaka Kondo
                            Yongjing Zhao
                            Katsuhisa Suzuki
                            Hideaki Nakane
                            Isao Murata

Organization of PI:

     Department of Earth and Planetary Science
     Graduate School of Science
     The University of Tokyo
     Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033, Japan
     phone:   +81-3-5841-4595
     fax:       +81-3-5841-4586
     e-mail:　koike@eps.s.u-tokyo.ac.jp

Principle of Operation: We have been measuring tropospheric column amounts of carbon monoxide (CO), ethyne (C₂H₂), ethane (C₂H₆), and hydrogen cyanide (HCN) using Fourier-transform infrared spectrometers (FTIR) which were placed at the Moshiri and Rikubetsu Observatories and Tsukuba Japan (Table 1).  Resolution of the instrumentals is 0.0013 cm-1 or 0.0024 cm-1.  Measurements began at these three sites in 1996, 1995, and 1998, respectively.  Amounts of CO, C₂H₂, C₂H₆, and HCN have been retrieved from the solar spectra in the micro-windows at 2058-2070 cm-1 and 2158.3 cm-1, 3250.7 cm-1, 2976.8 cm-1, and 3287.2 cm-1, respectively.  The precision and absolute accuracy of the total column measurements are 5-7% for CO and C₂H₆ and they are 8-15% for C₂H₂ and HCN.  The retrieved CO, C₂H₂, C₂H₆, and HCN data since 1995 show seasonal variations and changes within shorter time periods.  Measurements of these species will be made before, during, and after the TRACE-P deployment.  Since CO, C₂H₂, and C₂H₆ are mostly anthropogenically emitted over Asian continent, they are good indicators of the degree of influence from anthropogenic emissions.  HCN is likely produced near the earth’s surface by biomass burning and biological activity and it can be used as an indicator to assess this influence.

After the TRACE-P deployment, post-mission analyses will be made.  First, intercomparison of the FTIR observations with the DC-8 and P-3 aircraft observations will be made to confirm the consistency of the measurements.  Second, by combining FTIR data and aircraft data, spatial and temporal changes in CO, C₂H₂, C₂H₆, and HCN will be studied.  This analysis will place the aircraft observations in the context of seasonal changes of these key species.  Third, analyses using 3 dimensional chemistry transport model will be made to study sources and photochemical and transport processes, which control the distribution of these key species.  Because these processes change with season, a comparison of model results with our data can be a good test to assess our understanding on those processes.

Table 1

Name of site                  Location           

Moshiri                      44.4°N, 142.3°E

Rikubetsu                    43.5°N, 143.8°E

Tsukuba                     36.0°N, 140.1°E

References:

Li, Q., D.J. Jacob, I. Bey, R.M. Yantosca, Y. Zhao, Y. Kondo, and J.Notholt, Atmospheric hydrogen cyanide (HCN): Biomass burning source, ocean sink?, Geophys. Res. Lett.,  27, 357-360, 2000

Liu, X., et al., Comparison of HF and HCl vertical profiles from ground-based high-resolution infrared solar spectra with Halogen Occultation Experiment observations, J. Geophys. Res., 101, 10,175-10,181, 1996

Pougatchev, N.S., N.B. Jones, B.J. Connor, C.P. Rinsland, E. Becker, M.T. Coffey, V.S. Connors, P. Demoulin, A.V. Dzhola, H. Fast, E.I. Grechko, J.W. Hanningan, M. Koike, Y. Kondo, E. Mahieu, W.G. Mankin, R.L. Mittermeier, J. Norholt, H.G. Reichle Jr., B. Sen, L.P. Steele, G.C. Toon, L.N. Yurganov, R. Znader, and Y. Zhao, Ground-based infrared solar spectroscopic measurements of carbon monoxide during 1994 Measurement of Air Pollution From Space flights, J. Geophys. Res., 103, 19,317-19,325, 1998.

Rinsland, C. P., et al., Diurnal variation of atmospheric nitric oxide: Ground-based infrared spectroscopic measurements and their interpretation with time-dependent photochemical model calculations, J. Geophys. Res., 89, 9613-9622, 1984.

Zhao, Y., Y. Kondo, F.J. Murcray, X. Liu, M. Koike, K. Kita, H. Nakajima, I. Murata, and K. Suzuki, Carbon monoxide column abundances and tropospheric concentrations retrieved from high resolution ground-based infrared solar spectra at 43.5?N over Japan, J. Geophys. Res., 102,

     23,403-23,411, 1997.

Zhao, Y., Y. Kondo, X.Liu, M. Koike, H.Nakajima, I. Murata, F.J. Murcray, and K. Suzuki, Proc. Quadren. Ozone Symp. 1996, Spectroscopic measurements of carbon monoxide at 34.5 °N and 43.5 °N in Japan, 643-646, 1998.

Zhao, Y., Y. Kondo, F.J. Murcray, X. Liu, M. Koike, H. Irie, K. Suzuki, M. Sera, and Y. Ikegami, Seasonal variations of HCN over northern Japan measured by ground-based infrared solar spectroscopy, Geophys. Res. Lett., in press 2000.