226 research outputs found
Lidar measurement of stratospheric aerosol at Syowa Station, Antarctica
Lidar measurement on Antarctic aerosols were made during the Antarctic Middle Atmosphere (AMA) period, 1983 to 1985, at Syowa Station. Topics measured are winter enhancement aerosol layer and volcanic effect of El Chichon on the Antarctic stratosphere aerosols. The large depolarization ratio (maximum value was about 0.8) seems to support sublimation growth of ice crystals. The lidar measurements showed a meaningful time lag between aerosol content increase and depolarization ratio increase. Considering the balloon observations made in early winter, it was speculated that an increase in large particle number concentration also contributed to the winter enhancement. The El Chichon cloud spread to the Antarctic region by the beginning of 1983. The temporal change of integrated backscatter coefficient shows a clear decay pattern, although strong winter enhancement superposes
Lidar observation of the mesospheric sodium layer in Antarctica
The mesospheric sodium layer has been observed at Syowa Station in Antarctica during the wintering period of the 26th Japanese Antarctic Research Expedition. A lidar observation of the polar middle atmosphere at the station has been performed as a part of the Middle Atmosphere Program since 1983. At first stratospheric aerosols have been observed by the system based on a ruby laser. In 1985 a new transmitting system consisting of a tunable dye laser was added to that system to observe the sodium layer, too. The characteristics of the lidar system are given. The results of the mesospheric sodium layer observed on 42 nights during the period from March to October, 1985 are also given
Evaluating remediation of radionuclide contaminated forest near Iwaki, Japan, using radiometric methods
Radiometric surveys have been conducted in support of a project investigating the potential of biofuel power generation coupled with remediation of forests contaminated with radionuclides following the Fukushima Daiichi accident. Surveys conducted in 2013 and 2014 were used to determine the distribution and time dependence of radionuclides in a cedar plantation and adjacent deciduous forestry subject to downslope radionuclide migration, and a test area where litter removal was conducted. The radiocaesium results confirmed enhanced deposition levels in the evergreen areas compared with adjacent areas of deciduous forestry, implying significant differences in depositional processes during the initial interception period in 2011. Surveys were conducted both with and without a collimator on both occasions, which modified the angular response of the detector to separate radiation signals from above and below the detector. The combined data have been used to define the influence of radionuclides in the forest canopy on dose rate at 1 m, indicating that, in evergreen areas, the activity retained within the canopy even by 2013 contributed less than 5% of ground level dose rate. The time dependent changes observed allow the effect of remediation by litter removal in reducing radionuclide inventories and dose rates to be appraised relative natural redistribution processes on adjacent control areas. A 15x45 m area of cedar forest was remediated in September 2013. The work involved five people in a total of 160 person hours. It incurred a total dose of 40-50 µSv, and generated 2.1 t of waste comprising forest litter and understory. Average dose rates were reduced from 0.31 µSv h-1 to 0.22 µSv h-1, with nuclide specific analyses indicating removal of 30 ± 3% of the local radiocaesium inventory. This compares with annual removal rates of 10-15% where radionuclide migration down-slope over ranges of 10-50 m could be observed within adjacent areas. Local increases were also observed in areas identified as sinks. The results confirm the utility of time-series, collimated, radiometric survey methods to account for the distribution and changes in radionuclide inventory within contaminated forests. The data on litter removal imply that significant activity transfer from canopy to soil had taken place, and provide benchmark results against which such remediation actions can be appraised
Establishing the cut-off point for the Oppositional Defiant Behavior Inventory
The definitive version is available at www.blackwell-synergy.com.ArticlePSYCHIATRY AND CLINICAL NEUROSCIENCES. 62(1): 120-122 (2008)journal articl
Ground based NO2 and O3 measurements by visible spectrometer at Syowa Base (69 deg S), Antarctica
The column amounts of NO2 and ozone have been measured using visible spectroscopy at Syowa Base (69 deg S) since March 1990. Ozone was also measured at the same location with a Dobson spectrometer as well as ozonesondes being flown regularly. The characteristic features of the seasonal and diurnal variations of NO2 are presented. The column ozone values from the visible spectrometers are compared with the Dobson data. The very low values of NO2 in midwinter and early spring are consistent with the conditions predicted to be needed for heterogeneous ozone destruction in early spring. In late spring and summer of 1991, NO2 amounts were considerably smaller than in 1990, presumably due to the effect of Mt. Pinatubo eruption
6.EMEA International Symposium in Kanazawa, Japan
金沢大学大学院自然科学研究科名古屋大学Chinese Academy of SciencesProject Number 14404021, Peport of Research Project ; Grant-in-Aid for Scientific Research(B)(2), from April 2002 to March 2006, Edited by Muramoto,Ken-ichiroKamata, NaotoKawanishi, TakuyaKubo, MamoruLiu, JiyuanLee, Kyu-Sung , 人工衛星データ活用のための東アジアの植生調査、課題番号14404021, 平成14年度~平成17年度科学研究費補助金, 基盤研究(B)(2)研究成果報告書, 研究代表者:村本, 健一郎, 金沢大学自然科学研究科教
Processes of background KOSA outbreak : Lidar and balloon-borne measurements
金沢大学大学院自然科学研究科 環境科学名古屋大学金沢大学大学院自然科学研究科 電子科学Institute of Atomospheric Physics, Chinese Academy of Science2005 International Symposium on Environmental Mornitoring in East Asia -Remote Sensing and Forests-,Hosted The EMEA Project, Kanazawa University 21st=Century COE Program -Environmental Monitoring and Predicition of Long- and Short- Term Dynamics of Pan-Japan Sea Area- ,予稿集, EMEA 2005 in Kanazawa, 国際学術研究公開シンポジウム『東アジアの環境モニタリング』-リモートセンシングと森林-,年月日:200511月28日~29日, 場所:KKRホテル金沢, 金沢大学自然科学研究科, 主催:金沢大学EMEAプロジェクト, 共催:金沢大学21世紀COEプログラム「環日本海域の環境変動と長期・短期変動予測
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