Investigation of the ice nucleation properties of dust collected in northwest Greenland

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　統計数理研究所 セミナー室2（D304

Application of cloud particle sensor sondes for estimating the number concentration of cloud water droplets and liquid water content: case studies in the Arctic region

A cloud particle sensor (CPS) sonde is an observing system attached with a radiosonde sensor to observe the vertical structure of cloud properties. The signals obtained from CPS sondes are related to the phase, size, and number of cloud particles. The system offers economic advantages including human resource and simple operation costs compared with aircraft measurements and land-/satellite-based remote sensing. However, the observed information should be appropriately corrected because of several uncertainties. Here we made field experiments in the Arctic region by launching approximately 40 CPS sondes between 2018 and 2020. Using these data sets, a better practical correction method was proposed to exclude unreliable data, estimate the effective cloud water droplet radius, and determine a correction factor for the total cloud particle count. We apply this method to data obtained in October 2019 over the Arctic Ocean and March 2020 at Ny-Ålesund, Svalbard, Norway, to compare with a particle counter aboard a tethered balloon and liquid water content retrieved by a microwave radiometer. The estimated total particle count and liquid water content from the CPS sondes generally agree with those data. Although further development and validation of CPS sondes based on dedicated laboratory experiments would be required, the practical correction approach proposed here would offer better advantages in retrieving quantitative information on the vertical distribution of cloud microphysics under the condition of a lower number concentration

Interpretation of high cloud formation over the Tibetan Plateau by convective transport of water vapor and polluted air from Asia

金沢大学大学院自然科学研究科金沢大学自然計測応用研究センター場所：金沢大学自然科学研究科図書館棟1階，講演会場：図書館棟1階　大会議室，ポスター会場：図書館棟1階12会議室,主催・共催：文部科学省２１世紀COE「環日本海域の環境計測と長期・短期変動予測」， 大気環境学会， 金沢大学工学

Interpretation of high cloud formation over the Tibetan Plateau by convective transport of water vapor and polluted air from Asia

金沢大学大学院自然科学研究科金沢大学自然計測応用研究センター場所：東京大学弥生講堂，共催：文部科学省２１世紀COE「環日本海域の環境計測と長期・短期変動予測」，大気環境学

Enhancement of aerosols in monsoon anticyclone over the Tibetan Plateau : Ballon-borne measurements at Lhasa, China

金沢大学大学院自然科学研究科Chinese Academy of SciencePromoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

In which height does the ozone deficit occur over the Tibetan Plateau in summer? : Comparison of balloon-borne and statellite observations

金沢大学Chinese Academy of SciencePromoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

アジア大陸上空の自由対流圏～下部成層圏における大気エアゾールの評価

[研究概要

Hygroscopic mineral dust particles as influenced by chlorine chemistry in the marine atmosphere

Morphology and elemental compositions of individual dust particles were investigated with the use of Asian dust samples collected at a site along the Sea of Japan side of the archipelago. Our results indicate the preferential formation of chloride in Ca-containing dust particles (0.1 < Cl/Ca < 0.65) in cases when the particles contain little or no sulfate. Most of them are in an amorphous state and nearly spherical even under high vacuum. A likely explanation for the results is that highly soluble salts such as calcium chloride (CaCl2) are formed as a result of heterogeneous reactions of dust particles with chloride precursor gases (mostly, HCl) in the marine atmosphere. The chloride formation is expected to play an important role in enhancing the hygroscopicity of dust particles. Copyright 2009 by the American Geophysical Union

Summertime "ozone valley" over the Tibetan Plateau derived from ozonesondes and EP/TOMS data

金沢大学フロンティアサイエンス機構During the Asian summer monsoon period, total ozone over the Tibetan Plateau is much lower than that over the surrounding areas when compared at the same latitudes. This phenomenon called the "ozone valley" was investigated continuously with the use of ozonesondes and Earth Probe/Total Ozone Mapping Spectrometer (EP/TOMS). These measurements reveal that although relatively low ozone mixing ratios extend from the troposphere to the lower stratosphere, those near the tropopause (between about 150 and 70 hPa) largely contribute to lower total ozone over the Tibetan Plateau. Temperatures near the tropopause appear to be correlated with the observed ozone changes. Meteorological analyses show that this phenomenon is accompanied by the upper level monsoon anticyclone, which is characterized by deep convection over South Asia. These results suggest that lower ozone mixing ratios and colder temperatures near the tropopause are primarily due to convection, which is linked to the Asian summer monsoon. Copyright 2008 by the American Geophysical Union