Faculty Profiles - NAGAHAMA Tomoo

Papers - NAGAHAMA Tomoo

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Variations of nitric oxide in the mesosphere and lower thermosphere over Antarctica associated with a magnetic storm in April 2012 Reviewed

Isono Y., A. Mizuno, T. Nagahama, Y. Miyoshi, T. Nakamura, R. Kataoka, M. Tsutsumi, M. K. Ejiri, H. Fujiwara, H. Maezawa

Geophys. Res. Lett. 2014.4

Ground-based millimeter-wave observation of stratospheric ClO over Atacama, Chile in the mid-latitude Southern Hemisphere Reviewed

T. Kuwahara, T. Nagahama, H. Maezawa, Y. Kojima, H. Yamamoto, T. Okuda, N. Mizuno, H. Nakane, Y. Fukui, and A. Mizuno

Atmospheric Measurement Techniques Vol. 5 page： 2601-2611 2012.11

Language：English Publishing type：Research paper (scientific journal)

We have performed ground-based measurements of stratospheric chlorine monoxide (ClO) during the summer in 2009 over the Atacama highland, Chile, a new observing site in the mid-latitude region in the Southern Hemisphere, by using a millimeter-wave spectroscopic radiometer. The radiometer, equipped with a superconducting receiver and a digital Fourier spectrometer, was developed by Nagoya University. To reveal the diurnal variation of ClO, we retrieved the vertical mixing ratio profiles by the weighted-damped least-squares algorithm applied for the spectral data at 203 GHz obtained between 5 and 16 December 2009. The total error on the retrieval is estimated to be 20% to 30% in an altitude range from 40 km to 50 km. The amplitude of the diurnal variation is estimated as 33% of the daytime average at 40 km. The observed time variation shows a pattern similar to that of the previous works observed in the northern mid-latitude region.

DOI： doi:10.5194/amt-5-2601-2012

Aircraft measurements of carbon dioxide and methane for the calibration of ground-based high-resolution Fourier Transform Spectrometers and a comparison to GOSAT data measured over Tsukuba and Moshiri Reviewed

T. Tanaka, Y. Miyamoto, I. Morino, T. Machida, T. Nagahama, Y. Sawa, H. Matsueda, D. Wunch, S. Kawakami, and O. Uchino

Atmospheric Measurement Techniques Vol. 5 ( 8 ) page： 2003-2012 2012.8

Language：English Publishing type：Research paper (scientific journal)

Aircraft measurements of carbon dioxide and methane over Tsukuba (36.05° N, 140.12° E) (February 2010) and Moshiri (44.36° N, 142.26° E) (August 2009) were made to calibrate ground-based high-resolution Fourier Transform Spectrometers (g-b FTSs) and to compare with the Greenhouse gases Observing SATellite (GOSAT). By comparing the g-b FTS measurements with the airborne measurements, the column-averaged dry air mole fractions of CO2 (XCO2) and CH4 (XCH4) retrieved from the g-b FTS measurements at Tsukuba were biased low by 0.33 ± 0.11% for XCO2 and 0.69 ± 0.29% for XCH4. The g-b FTS values at Moshiri were biased low by 1.24% for XCO2 and 2.11% for XCH4. The GOSAT data show biases that are 3.1% ± 1.7% lower for XCO2 and 2.5% ± 0.8% lower for XCH4 than the aircraft measurements obtained over Tsukuba.

DOI： doi:10.5194/amt-5-2003-2012

Effects of atmospheric light scattering on spectroscopic observations of greenhouse gases from space: Validation of PPDF-based CO2 retrievals from GOSAT Reviewed

S. Oshchepkov, et al.

Journal of Geophysical Research Vol. 117 2012.6

Language：English Publishing type：Research paper (scientific journal)

This report describes a validation study of Greenhouse gases Observing Satellite (GOSAT) data processing using ground-based measurements of the Total Carbon Column Observing Network (TCCON) as reference data for column-averaged dry air mole fractions of atmospheric carbon dioxide (XCO2). Our results reveal effects of optical path lengthening over Northern Hemispheric stations, essentially from May-September of each year, and of optical path shortening for sun-glint observations in tropical regions. Removal of observations that were highly contaminated by aerosol and cloud from the GOSAT data set resulted in acceptable agreement in the seasonal variability of XCO2 over each station as compared with TCCON measurements.

DOI： doi:10.1029/2012JD017505

Overview and early results of the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) Reviewed

Kikuchi, K., T. Nishibori, S. Ochiai, H. Ozeki, Y. Irimajiri, Y. Kasai, M. Koike, T. Manabe, K. Mizukoshi, Y. Murayama, T. Nagahama, T. Sano, R. Sato, M. Seta, C. Takahashi, M. Takayanagi, H. Masuko, J. Inatani, M. Suzuki, and M. Shiotani

Journal of Geophysical Research-Atmospheres Vol. 115 ( D23306 ) 2010.12

Language：English Publishing type：Research paper (scientific journal)

The Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) was successfully launched and attached to the Japanese Experiment Module (JEM) on the International Space Station (ISS) on 25 September 2009. It has been making atmospheric observations since 12 October 2009 with the aid of a 4 K mechanical cooler and superconducting mixers for submillimeter limb-emission sounding in the frequency bands of 624.32-626.32 GHz and 649.12-650.32 GHz. On the basis of the observed spectra, the data processing has been retrieving vertical profiles for the atmospheric minor constituents in the middle atmosphere, such as O3 with isotopes, HCl, ClO, HO2, BrO, and HNO3. Results from SMILES have demonstrated its high potential to observe atmospheric minor constituents in the middle atmosphere. Unfortunately, SMILES observations have been suspended since 21 April 2010 owing to the failure of a critical component.

DOI： doi:10.1029/2010JD014379

Remotely operable compact instruments for measuring atmospheric CO2 and CH4 column densities at surface monitoring sites Reviewed

Kobayashi, N., G. Inoue, M. Kawasaki, H. Yoshioka, M. Minomura, I. Murata, T. Nagahama, Y. Matsumi, T. Tanaka, I. Morino, and T. Ibuki

Atmospheric Measurement Techniques Vol. 3 page： 1-10 2010.4

Language：English Publishing type：Research paper (scientific journal)

Remotely operable compact instruments for measuring atmospheric CO2 and CH4 column densities were developed in two independent systems. One utilizing a grating based desktop optical spectrum analyzer (OSA) with a resolution enough to resolve rotational lines of CO2 and CH4 in the region of 1565-1585 and 1674-1682 nm, respectively. The other is an application of an optical fiber Fabry-Perot interferometer (FFPI) to obtain the CO2 column density. The CO2 and CH4 column densities deduced were in excellent agreement with those measured by a Fourier transform spectrometer with high resolution.

Column-averaged volume mixing ratio of CO2 measured with ground-based Fourier transform spectrometer at Tsukuba Reviewed

Hirofumi Ohyama, Isamu Morino, Tomoo Nagahama, Toshinobu Machida, Hiroshi Suto, Hiroyuki Oguma, Yousuke Sawa, Hidekazu Matsueda, Nobuo Sugimoto, Hideaki Nakane, and Kazumichi Nakagawa

Journal of Geophysical Research -Atmospheres Vol. 114 page： doi:10.1029/2008JD011465 2009.9

Language：English Publishing type：Research paper (scientific journal)

We retrieved CO2 volume mixing ratios (VMRs) from solar absorption spectra in the 1.6-μm CO2 (30012-00001) band measured with a ground-based high-resolution Fourier transform spectrometer (FTS) at Tsukuba, Japan, using profile retrieval and scaling retrieval algorithms. We derived the time series of the column-averaged CO2 VMRs (X CO2) from December 2001 to December 2007.

Search of SO2 in the Martian atmosphere by ground-based submillimeter observation Reviewed

Nakagawa, H., Y. Kasaba, H. Maezawa, A. Hashimoto, H. Sagawa, I. Murata, S. Okano, S. Aoki, N. Moribe, A. Mizuno, M. Momose, T. Ohnishi, N. Mizuno, and T. Nagahama

Planet. Space Science Vol. 57 page： 2123-2127 2009

Ground-based millimeter-wave observations of water vapor emission (183 GHz) at Atacama, Chile Reviewed

Kuwahara, T., A. Mizuno, T. Nagahama, H. Maezawa, A. Morihira, N. Toriyama, S. Murayama, M. Matsuura, T. Sugimoto, S. Asayama, N. Mizuno, T. Onishi, and Y. Fukui

Advances in Space Research Vol. 42 ( 1 ) page： 1167-1171 2008.10

Language：English Publishing type：Research paper (scientific journal)

We report the first results of ground-based millimeter-wave measurements of 183 GHz atmospheric water vapor spectra from Atacama highland (4800 m alt.), Chile. The measurements were carried out in December 2005 by using a spectroscopic radiometer equipped with a superconductive heterodyne receiver.

DOI： doi:10.1016/j.asr.2007.11.030

Ground-Based Millimeter-Wave Radiometer for Measuring the Stratospheric Ozone over Rikubetsu, Japan Reviewed

Tomoo NAGAHAMA, Hideaki NAKANE, Yasumi FUJINUMA, Atsushi MORIHIRA, Akira MIZUNO, Hideo OGAWA, and Yasuo FUKUI

Journal of the Meteorological Society of Japan Vol. 85 ( 4 ) page： 495-509 2007.8

Continuous Measurements of the Stratospheric and Mesospheric Ozone by Using Ground-based Millimeter-wave Radiometers Reviewed

Tomoo Nagahama, Akira Mizuno, Hiroyuki Maezawa, Hideaki Nakane, Yasumi Fujinuma, Atsushi Morihira, Hideo Ogawa, and Yasuo Fukui

Proceedings of International Conference on Submillimeter Science and Technology (ICSST04) page： 20-23 2006

A semi-annual variation of ozone in the middle mesosphere observed with the millimeter-wave radiometer at Tsukuba, Japan Reviewed

Nagahama, T., H. Nakane, Y. Fujinuma, H. Ogawa, A. Mizuno, and Y. Fukui

Journal of Geophysical Research -Atmospheres Vol. 108 page： 10.1029/2003JD003724 2003

Millimeter-wave radiometer for the measurement of stratospheric ClO using a superconductive (SIS) receiver installed in the southern hemisphere Reviewed

Mizuno, A., T. Nagahama, A. Morihira, H. Ogawa, N. Mizuno, Y. Yonekura, H. Yamamoto, H. Nakane, and Y. Fukui

International Journal of Infrared and Millimeter Waves Vol. 23 page： 981-995 2002

Ground-based millimeter-wave observations of ozone in the upper stratosphere and mesosphere at Tsukuba and Nagoya Reviewed

Nagahama, T., H. Nakane, M. Ninomiya, H. Ogawa, and Y. Fukui

Advances in Space Research Vol. 26 page： 1017-1020 2000

Ground-based millimeterwave instrument for measurement of stratospheric ClO using a superconductive (SIS) receiver Reviewed

Fukui, Y., H. Ogawa, K. C. Xiao, Y. Iwasaka, H. Nakane, and T. Nagahama

Advances in Space Research Vol. 26 page： 975-978 2000

Ground-based millimeter-wave observations of ozone in the upper stratosphere and mesosphere over Tsukuba Reviewed

Nagahama, T., H. Nakane, Y. Fujinuma, M. Ninomiya, H. Ogawa, and Y. Fukui

Earth, Planets and Space Vol. 51 page： 1287-1296 1999

A spatially complete 13CO J=1-0 survey of the Orion A cloud Reviewed

Nagahama, T., A. Mizuno, H. Ogawa, and Y. Fukui

Astronomical Journal Vol. 116 page： 336-348 1998

Observations of C18O (J=1-0) emission spectrum in the dark cloud L1211 Reviewed

Yu, Z. -Y., Y. Fukui, and T. Nagahama

Chinese Astronomy and Astrophysics Vol. 20 page： 38-44 1996

The new observation of C18O(J=1-0) molecular emission in the Cepheus OB3 molecular cloud Reviewed

Yu, Z. -Y., T. Nagahama, and Y. Fukui

Astrophysical Journal Vol. 471 page： 867-870 1996

Observation of C18O (J=1-0) emission from Cepheus C Reviewed

Yu, Z. -Y., T. Nagahama, and Y. Fukui

Chinese Astronomy and Astrophysics Vol. 20 page： 355-357 1996

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