Simultaneous observations of stratospheric and mesospheric water vapor isotopomers in a tropical part of Chile

智利热带地区平流层和中层水蒸气同位素的同时观测

• 批准号: 15253004
• 负责人: MIZUNO Akira
• 金额: $ 25.46万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15253004/
• 关键词: Middle atmosphere; Atmospheric minor constituent; Remote sensing; Microwave radiometer; Superconductive receiver; Ground-based observation

The aim of this project is to observe temporal and spatial variation of water vapor isotopic ratio in the middle atmosphere in order to understand the formation and transportation mechanism of water vapor. We developed a new radiometer system to obtain mm-wave H_2O (183GHz) and H_2^<18>O (203GHz) spectra simultaneously. The new system was installed at Atacama highland at an altitude of 4800m, since the 183GHz H_2O spectrum is hardly observable in low altitude places. The results through a two-year period of the project are summarized bellow(1)Development of the dual-frequency mm-wave radiometer We designed new radiometer system equipped with two superconductive receivers to observe different water vapor isotopomers simultaneously. The two receivers are set in a common 4-Kelvin cryostat, while the optical paths for the two receivers are completely separated. In the laboratory, we confirmed that the new system was functioning well.(2)H_2^<18>O observation at Las Campanas precedent to Atacama : From September 2003 to February 2004,we carried out continuous observations of H_2^<18>O at Las Campanas Observatory (alt.2,500m) in Chile. Since the spectral intensity of H_2^<18>O is very weak, Ta〜50mK, no such continuous ground-based observation has been ever done. We found that the seasonal variation of H_2^<18>O mixing ratio is similar to that of normal H_2O.(3)183GHz H_2O observation in Atacama : The new radiometer system was installed in Atacama in September 2004,yet the instrumental setup was delayed because of bad working condition and unexpected hardware troubles due to low pressure environment at the site. We did not perform the dual-frequency operation during the project period, whereas we succeeded in detecting 183GHz H_2O spectrum in the single-frequency observation mode. We exhibited the feasibility of water vapor isotopic ratio measurements in Atacama and established the foundations for future observation through this project.

本项目的目的是观测大气中层水汽同位素比值的时空变化，以了解水汽的形成和输送机制。我们研制了一套新的毫米波H_2O（183 GHz）和H_2^<18>O（203 GHz）光谱辐射计系统。新系统安装在海拔4800米的阿塔卡马高原，因为183 GHz的H_2O频谱在低海拔地区很难观测到。（1）双频毫米波辐射计的研制我们设计了一种新的毫米波辐射计系统，它配备了两个双通道接收机，可以同时观测不同的水汽同位素。这两个接收器被设置在一个共同的4开尔文低温恒温器，而两个接收器的光路是完全分开的。在实验室里，我们证实新系统运行良好。(2)H 2003<18>年9月至2004年2月，我们<18>在智利的Las Campanas天文台（海拔2,500米）对H_2^ O进行了连续观测。由于H_2^ O的光谱强度<18>很弱，Ta约为50 mK，因此从未进行过这样的地面连续观测。我们发现H_2^ O混合比的季节变化<18>与正常H_2O的季节变化相似。（3）阿塔卡马183 GHz H_2O观测：2004年9月在阿塔卡马安装了新的辐射计系统，但由于现场低气压环境造成的恶劣工作条件和意外硬件故障，仪器安装延迟。在项目期间，我们没有进行双频操作，但我们成功地探测到183 GHz的H_2O光谱在单频观测模式。我们展示了在阿塔卡马进行水蒸气同位素比测量的可行性，并通过该项目为未来的观测奠定了基础。

项目成果

An Experimental Study of Harmonic SIS Mixing at 205-235GHZ

205-235GHZ 谐波 SIS 混频的实验研究

• 发表时间: 2003
• 期刊: IEEE Transactions on Applied Superconductivity 13
• 作者: Sasaki;Mamoru;Hiroya Andoh;Kecheng.Xiao
• 通讯作者: Kecheng.Xiao

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

• DOI: 10.1029/2003jd003724
• 发表时间: 2003-11
• 期刊: Journal of Geophysical Research
• 作者: T. Nagahama;H. Nakane;Y. Fujinuma;H. Ogawa;A. Mizuno;Y. Fukui

Measurements of stratospheric water vapor isotopomers by using a millimeter-wave radiometer with a superconductive receiver

使用带有超导接收器的毫米波辐射计测量平流层水蒸气同位素

• 发表时间: 2004
• 期刊: Proceedings of the 20th Quadrennial Ozone symposium(Ed.C.Zerefos)
• 作者: Mizuno;A;Nagahama;T.;Maezawa;H.;Fukui;Y.;Mizuno;N.;Nakane;H.;Ogawa;H.;Yonekura;Y.;Asayama;S.;Morihira;A.
• 通讯作者: A.

An Integrated Sideband-Separating SIS Mixer Based on Waveguide Split Block for 100 GHz Band with 4.0–8.0 GHz IF

• DOI: 10.1023/b:ijim.0000012766.63015.8c
• 发表时间: 2004
• 期刊: International Journal of Infrared and Millimeter Waves
• 作者: S. Asayama;H. Ogawa;T. Noguchi;Kazuji Suzuki;H. Andoh;A. Mizuno

Continuous measurements of the stratospheric and mesespheric Ozone by using ground-based millimeter-wave radiometers

使用地面毫米波辐射计连续测量平流层和中层臭氧

• 发表时间: 2005
• 期刊: Proc.of 1st International Conference on Submillimeter Science and Technology (ICSST 04) (In Press)
• 作者: TANIGUCHI;Yoshiaki;佐々木 衞;矢野 裕俊;白鳥 義彦;矢野 裕俊;過 放;Tomoo Nagahama;木原 俊行;Tomoo Nagahama
• 通讯作者: Tomoo Nagahama