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

DOI： 10.1016/j.atmosenv.2022.119261

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

DOI： 10.1016/j.atmosenv.2022.119287

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

DOI： 10.11203/jar.37.136

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

DOI： 10.1007/s10872-021-00625-2

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：公益社団法人 大気環境学会  

DOI： 10.11298/taiki.55.191

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

DOI： 10.5194/amt-12-6465-2019

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

DOI： 10.1007/s10874-019-09391-4

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

DOI： 10.5194/acp-19-219-2019

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Copernicus Publications  

DOI： 10.5194/acp-18-18203-2018

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

DOI： 10.1007/s10311-018-00820-6

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

DOI： 10.2116/bunsekikagaku.67.333

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We investigate the geometry of two-dimensional polygonal cracking that forms on the air-exposed surface of dried starch slurries. Two different kinds of starches, made from potato and corn, exhibited distinguished crack evolution, and there were contrasting effects of slurry thickness on the probability distribution of the polygonal cell area. The experimental findings are believed to result from the difference in the shape and size of starch grains, which strongly influence the capillary transport of water and tensile stress field that drives the polygonal cracking.

DOI： 10.1103/PhysRevE.96.023003

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Numerous algorithms have been proposed to retrieve chlorophyll-a concentrations in Case 2 waters; however, the retrieval accuracy is far from satisfactory. In this research, seven algorithms are assessed with different band combinations of multispectral and hyperspectral bands using linear (LN), quadratic polynomial (QP) and power (PW) regression approaches, resulting in altogether 43 algorithmic combinations. These algorithms are evaluated by using simulated and measured datasets to understand the strengths and limitations of these algorithms. Two simulated datasets comprising 500,000 reflectance spectra each, both based on wide ranges of inherent optical properties (IOPs), are generated for the calibration and validation stages. Results reveal that the regression approach (i.e., LN, QP, and PW) has more influence on the simulated dataset than on the measured one. The algorithms that incorporated linear regression provide the highest retrieval accuracy for the simulated dataset. Results from simulated datasets reveal that the 3-band (3b) algorithm that incorporate 665-nm and 680-nm bands and band tuning selection approach outperformed other algorithms with root mean square error (RMSE) of 15.87 mg.m(-3), 16.25 mg.m(-3), and 19.05 mg.m(-3), respectively. The spatial distribution of the best performing algorithms, for various combinations of chlorophyll-a (Chla) and non-algal particles (NAP) concentrations, show that the 3b_tuning_QP and 3b_680_QP outperform other algorithms in terms of minimum RMSE frequency of 33.19% and 60.52%, respectively. However, the two algorithms failed to accurately retrieve Chla for many combinations of Chla and NAP, particularly for low Chla and NAP concentrations. In addition, the spatial distribution emphasizes that no single algorithm can provide outstanding accuracy for Chla retrieval and that multi-algorithms should be included to reduce the error. Comparing the results of the measured and simulated datasets reveal that the algorithms that incorporate the 665-nm band outperform other algorithms for measured dataset (RMSE = 36.84 mg.m(-3)), while algorithms that incorporate the band tuning approach provide the highest retrieval accuracy for the simulated dataset (RMSE = 25.05 mg.m(-3)).

DOI： 10.3390/s17081746

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Many approaches have been proposed for monitoring the eutrophication of Case 2 waters using remote sensing data. Semi-analytical algorithms and spectrum matching are two major approaches for chlorophyll-a (Chla) retrieval. Semi-analytical algorithms provide indices correlated with phytoplankton characteristics, (e.g., maximum and minimum absorption peaks). Algorithms' indices are correlated with measured Chla through the regression process. The main drawback of the semi-analytical algorithms is that the derived relation is location and data limited. Spectrum matching and the look-up table approach rely on matching the measured reflectance with a large library of simulated references corresponding to wide ranges of water properties. The spectral matching approach taking hyperspectral measured reflectance as an input, leading to difficulties in incorporating data from multispectral satellites. Consequently, multi-algorithm indices and the look-up table (MAIN-LUT) technique is proposed to combine the merits of semi-analytical algorithms and look-up table, which can be applied to multispectral data. Eight combinations of four algorithms (i.e., 2-band, 3-band, maximum chlorophyll index, and normalized difference chlorophyll index) are investigated for the MAIN-LUT technique. In situ measurements and Medium Resolution Imaging Spectrometer (MERIS) sensor data are used to validate MAIN-LUT. In general, the MAIN-LUT provide a comparable retrieval accuracy with locally tuned algorithms. The most accurate of the locally tuned algorithms varied among datasets, revealing the limitation of these algorithms to be applied universally. In contrast, the MAIN-LUT provided relatively high retrieval accuracy for Tokyo Bay (R-2 = 0.692, root mean square error (RMSE) = 21.4 mg m(-3)), Lake Kasumigaura (R-2 = 0.866, RMSE = 11.3 mg m(-3)), and MERIS data over Lake Kasumigaura (R-2 = 0.57, RMSE = 36.5 mg m(-3)). The simulated reflectance library of MAIN-LUT was generated based on inherent optical properties of Tokyo Bay; however, the MAIN-LUT also provided high retrieval accuracy for Lake Kasumigaura. MAIN-LUT could capture the spatial and temporal distribution of Chla concentration for Lake Kasumigaura.

DOI： 10.3390/rs9060556

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The impact of heterogeneous reactions on the chemical components and mixing state of dust particles are investigated by observations and an air quality model over northern China between March 27, 2015 and April 2, 2015. Synergetic observations were conducted using a polarization optical particle counter (POPC), a depolarized two-wavelength Lidar and filter samples in Beijing. During this period, dust plume passed through Beijing on March 28, and flew back on March 29 because of synoptic weather changes. Mineral dust mixed with anthropogenic pollutants was simulated using the Nested Air Quality Prediction Modeling System (NAQPMS) to examine the role of heterogeneous processes on the dust. A comparison of observations shows that the NAQPMS successfully reproduces the time series of the vertical profile, particulate matter concentration, and chemical components of fine mode (diameter <= 2.5 mu m) and coarse mode (2.5 mu m < diameter <= 10 mu m) particles. After considering the heterogeneous reactions, the simulated nitrate, ammonium, and sulfate are in better agreement with the observed values during this period. The modeling results with observations show that heterogeneous reactions are the major mechanisms producing nitrate reaching 19 mu g/m(3), and sulfate reaching 7 mu g/m(3), on coarse mode dust particles, which were almost 100% of the coarse mode nitrate and sulfate. The heterogeneous reactions are also important for fine mode secondary aerosols, for producing 17% of nitrate and 11% of sulfate on fine mode dust particles, with maximum mass concentrations of 6 mu g/m(3) and 4 mu g/m(3). In contrast, due to uptake of acid gases (e.g. HNO3 and SO2) by dust particles, the fine mode anthropogenic ammonium nitrate and ammonium sulfate decreased. As a result, the total fine mode nitrate decreased with a maximum of 14 mu g/m(3), while the total fine mode sulfate increased with a maximum of 2 mu g/m(3). Because of heterogeneous reactions, 15% of fine mode secondary inorganic aerosols and the entire coarse mode nitrate and sulfate were internally mixed with dust particles. The significant alterations of the chemical composition and mixing state of particles due to heterogeneous reactions are important for the direct and indirect climate effects of dust and anthropogenic aerosols. (C) 2017 The Authors. Published by Elsevier Ltd.

DOI： 10.1016/j.atmosenv.2017.03.044

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Natural mineral dust and heavy anthropogenic pollution and its complex interactions cause significant environmental problems in East Asia. Due to restrictions of observing technique, real-time morphological change in Asian dust particles owing to coating process of anthropogenic pollutants is still statistically unclear. Here, we first used a newly developed, single-particle polarization detector and quantitatively investigate the evolution of the polarization property of backscattering light reflected from dust particle as they were mixing with anthropogenic pollutants in North China. The decrease in observed depolarization ratio is mainly attributed to the decrease of aspect ratio of the dust particles as a result of continuous coating processes. Hygroscopic growth of Calcium nitrate (Ca(NO3)(2)) on the surface of the dust particles played a vital role, particularly when they are stagnant in the polluted region with high RH conditions. Reliable statistics highlight the significant importance of internally mixed, 'quasi-spherical' Asian dust particles, which markedly act as cloud condensation nuclei and exert regional climate change.

DOI： 10.1038/s41598-017-00444-w

Web of Science

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

DOI： 10.1016/j.jqsrt.2016.06.038

Web of Science

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

DOI： 10.2322/tastj.14.Pn_7

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAIWAN ASSOC AEROSOL RES-TAAR  

Atmospheric trace gases CO, O-3, and SO2 were observed at the summit of Mt. Fuji (3776 ma.s.l.) during the summer of 2013. Considerable variations were observed in the concentrations of CO and O-3; however, they were correlated in most cases. Trends analyzed through backward trajectory calculations showed lower concentrations of CO and O-3 transported from the Pacific Ocean and South East Asia directions, while higher concentrations were detected from the direction of the Asian continent. High O-3 and low CO concentrations were observed during some periods; in these air masses, water content of the air was low indicating that the air originated from high altitudes and was influenced by the stratosphere. Gaseous SO2 was mostly lower than the detection limit of the instrument used for measurement (0.06 ppbv), but on August 20-21, high SO2 spikes of about 5 ppbv were observed. Backward and forward trajectory calculations confirmed that volcanic smoke from the Sakurajima volcano was transported to the summit of Mt. Fuji.

DOI： 10.4209/aaqr.2015.11.0632

Web of Science

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

DOI： 10.5194/acp-16-9863-2016

Web of Science

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

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

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

Language：English   Publishing type：(MISC) Introduction and explanation (international conference proceedings)  

DOI： 10.1051/epjconf/201611908007

Scopus

Other Link： http://orcid.org/0000-0002-1843-4291

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.11203/jar3027

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1117/12.21956

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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER GEOPHYSICAL UNION  

We observed a long-lasting dust event from 25 May to 2 June 2014, using a polarization optical particle counter (POPC). The transport of dust plumes over East Asia was verified on the basis of observations of Moderate Resolution Imaging Spectroradiometer, a lidar network, and surface synoptic observation stations. Mixing of dust and anthropogenic pollutants was investigated according to the variation in the depolarization ratio as a function of particle size. The nonsphericity of dust particles varied due to the impact of anthropogenic pollutants on their pathway. In the coarse mode, dust particles always had a clear nonspherical configuration, although large amounts of nitrate were also present. Supermicron particles are occasionally present in a spherical configuration, possibly due to the complex mixing of natural dust and anthropogenic particles. Statistically, similar to 64% of the total nitrate mass was deemed to be transported from outside of Japan due to a trapping effect in the dust plume.

DOI： 10.1002/2014GL062491

Web of Science

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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

DOI： 10.15748/jasse.2.1

Web of Science

Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

New shipborne aureolemeter was developed to improve the sun-tracking performance for accurate measurements of not only direct but also circumsolar radiation, even on a vessel weltering. Sun position is determined by a real-time image processing system with a CCD camera. The accuracy of the sun position determination is finer than 0.01 degrees. The radiometer is tracked the sun under a feedback control with the derived sun position. For a sky radiance distribution measurement, the control target position on the CCD camera image is shifted a pixel corresponding to a measuring scattering angle. In the case of a scattering angle larger than 7 degrees, the radiometer's tracking is conducted under feed forward control on the basis of the angle of roll and pitch monitored with a gyroscope. The instrument constants were determined from a Langley plot method. Test observation was conducted onboard the Antarctic research vessel (R/V) Shirase during the 56th Japanese Antarctic Research Expedition (JARE-56; 2014-2015). Aerosol optical thickness (AOT) was measured. The measurement of the sky radiance distribution is being analyzed to derive the aerosol optical properties.

DOI： 10.1117/12.2195691

Web of Science

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

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

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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Measurements of the water-soluble organic nitrogen (WSON) in the aerosols were conducted over three years at two sites; an urban site in Kofu and a forested site in Fujiyoshida, Japan. Our preliminary experiment demonstrated that the adsorption of organic gases on the filter had little effect on the measurement of the WSON. The mean concentration of the WSON in the aerosols at the urban site was 0.221 mu g m(-3), which was higher than that of 0.101 mu g m(-3) at the forested site. Large portions of the WSON were found in the fine-mode range; 90.3% at the urban site and 86.4% at the forested site. The WSON constituted a significant fraction of the water-soluble total nitrogen (WSTN) in the aerosols; 11.1% and 16.2% of the WSTN in the coarse and fine particles, respectively, at the urban site, and 11.5% and 13.1% in the coarse and fine particles, respectively, at the forested site. The fine-mode WSON would be derived from the reaction of its basic precursor gases with particulate or gaseous acidic species. Photochemical reactions and combustion emissions could also be important sources of the fine-mode WSON. In the coarse-mode range, on the other hand, vegetation sources could be an important source of the WSON. The mean concentration of urea in the aerosols at the urban site was 1.7 ngN m(-3). A large portion (87.2%) of the urea was partitioned into the fine-mode range. Urea is a minor compound in the particulate WSON in this region with contributions to about 1% of the WSON. Approximately 26% of the dry deposition of the WSTN was attributed to the WSON in the cold season. The significant part (96.5%) of the WSON was deposited by coarse aerosols. Coarse-mode WSON is important for discussing the dry deposition fluxes of the WSON and fixed nitrogen. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.atmosenv.2014.06.037

Web of Science

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

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

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Cloud radiation interactions are important in the global climate system. However, an understanding of mixed-phase boundary layer clouds in the Arctic remains poor. During May-June 2011, ground-based in situ measurements were made at Zeppelin Station, operated by the Norwegian Polar Institute (altitude 474 m) in Ny-Alesund (78.9 degrees N, 11.9 degrees E), Svalbard. The instruments used comprised a Cloud, Aerosol and Precipitation Spectrometer (CAPS), and a Cloud Particle Microscope imager. The CAPS incorporated a Cloud and Aerosol Spectrometer and Cloud Imaging Probe (CIP). During the observation period, clouds associated with cyclonic disturbances and those associated with outbreaks of westerly cold air masses from the sea were observed. Atmospheric temperature during all measurements ranged from 0 to -5 degrees C. In every case, columns were the major type of ice particle measured by the CAPS-CIP. Cloud microphysical properties were observed continuously on 9 June 2011. Size spectra, liquid/ice water content, and particle effective size changed depending on progress stages. Based on the observed microphysics, optical properties were calculated and investigated. Optical properties were determined mainly by those of liquid water particles, even during periods when the relative contribution of ice particles to total water content was at the maximum. It was confirmed that the wavelength region of 1.6 and 2.2 mu m can be used in remote sensing. This study shows that it is possible to measure detailed changes of cloud properties in the Arctic region by using instruments installed at a ground-based mountain station. (C) 2013 Elsevier B.V. and NIPR. All rights reserved.

DOI： 10.1016/j.polar.2013.11.001

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

To examine the evaporation and its application to understand the chemical properties, formation mechanisms, and sources of the water-soluble organic carbon (WSOC) in ambient aerosols, field measurements of carbonaceous compounds in the aerosols were conducted at an urban site in a provincial city, Kofu, Japan. The WSOC in the fine particles evaporated with heating at lower temperature than that in the coarse particles, whereas the water-insoluble organic carbon (WIOC) in the fine particles remained at higher temperature compared with that in the coarse particles. In the fine particles, the WSOC would be more volatile than the WIOC. In the coarse particles, on the other hand, the volatility of the WSOC would be similar with that of the WIOC, and both would have the volatility between the fine-mode WSOC and WIOC. Significant parts of the WSOC were not evolved at 340 degrees C in air. Adsorption of gaseous organic compounds on quartz fiber filters influenced the measurements of the total carbon and WSOC, especially the carbon evolved at and lower than 120 degrees C. The evaporation of single standards of four typical water-soluble organic compounds was also examined, of which the results indicated a significant contribution of low molecular weight organic compounds to the WSOC, especially the fine-mode WSOC. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jaerosci.2013.09.005

Web of Science

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

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE  

Polarization optical particle counter (POPC) capable of measuring particle shape or sphericity was developed, which uses detection of polarization of light scattered by particles. Sensors that detected P- and S- polarization components are incorporated at scattering angle of 120° in addition to ordinary sensor located at the angle of 60°. The particle size is derived from the pulse height detected with the ordinary sensor. The size thresholds were determined by measurements of standard particles of polystyrene latex bead. Polarization of particle is calculated as the ratio of S polarization component to the sum of all components. The POPC field observations were started in Fukuoka, Japan on 22th February 2012. The mass concentration of each aerosol type such as air pollution, dust, and sea-salt particles was calculated from the POPC measurement with estimated aerosol type classification rule. The result shows apparent seasonal variation of dust mass concentration. The estimated bulk depolarization ratios of each aerosol type in all results corresponded with each other. The values of air pollution, dust, and sea-salt particles were 0.17-0.24, 0.55-0.67, and 0.06-0.12, respectively. This result will contribute the LIDAR data analysis. The POPC thus is capable of measuring particle shape as well as size for each individual particle. ©2012 SPIE.

DOI： 10.1117/12.979634

Scopus

Other Link： http://orcid.org/0000-0002-6396-788X

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：公益社団法人 土木学会  

Remote sensing reflectance (Rrs) and absorption coefficient were measured by carrying out field observation in Tokyo bay to figure out optical properties of high eutrophicated coastal area and to develop estimated model of high concentrated Chlorophyll-a (Chl-a). It was the result that when Rrs of high concentrated Chl-a was observed, green wavelength of Rrs decreases, red wavelength of Rrs increases, and absorption coefficient of the phytoplankton of the green wavelength increases. Based on consideration, we developed estimation model for high concentrated Chl-a using the correction term of estimated error. In the result of verification of suggested model, it could appropriately improve the accuracy. Furthermore, behavior of Chl-a distribution in Tokyo Bay was discussed using the satellite data which was applied for suggested model.

DOI： 10.2208/kaigan.68.I_1486

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

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

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

The influence of the optical properties of inorganic suspended solids (ISS) on in-water algorithms was evaluated using an optical model in highly turbid coastal water, whose ISS concentration reached several hundred grams per cubic metre. The measurements were conducted in the upper Gulf of Thailand. The backscattering coefficient of the ISS was calculated using the Lorenz-Mie scattering theory. On the basis of the measurement, the ISS size distribution was parameterized as a function of ISS concentration, and both the spherical and non-spherical particle shape models were evaluated. For ISS concentrations of 10 g m(-3), an estimate of the chlorophyll-a (chl-a) concentration within a factor of 2 on a logarithmic scale is possible in a [chl-a] range of 4-30 mg m(-3). The differential coefficient of remote sensing reflectance was calculated to evaluate its respective sensitivities for chl-a and ISS concentrations. The use of radiometric data at 670 nm (700-900 nm) is valid for in-water algorithms used to estimate chl-a (ISS) concentration in highly turbid coastal waters.

DOI： 10.1080/01431161.2010.542193

Web of Science

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

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

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

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

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：(MISC) Prompt report, short report, and research note, etc. (bulletin of university, research institution)  

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

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Association of Aerosol Science and Technology  

Filter sampling was conducted at the summit of Mt. Fuji to observe microphysical properties of Asian dust in the free troposphere. In order to avoid influence of local mineral dust elevated from near the summit, the filter sampling was conducted only during the nighttime from 0:00 to 6:00. Volume-size distribution of water-insoluble aerosol particles was measured by using a Coulter Multisizer. The samples with the minimum local influence showed the size distributions with the mode diameters of 3.1 and 4.5 μm. These mode diameters correspond to those measured on the ground during Asian dust event. Therefore, the measured water-insoluble aerosol particles were of background Asian dust in the free troposphere. In addition, a narrow size distribution with a mode diameter of 1.8 μm which could be the contribution of inorganic ash spheres also appeared. The measurement of sample which was separated by wind direction and speed during 2006 summer showed the mode diameter of around 5-6 μm, which would be of the mineral dust elevated from near the summit. For proper observation of mineral dust (water-insoluble particle) in the free troposphere, it is required to adopt the sampling time from 0:00 till sunrise.

DOI： 10.11203/jar.25.167

CiNii Books

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

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

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

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

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

DOI： 10.1029/2007JD009410

Web of Science

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

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER METEOROLOGICAL SOC  

A Coulter Multisizer, which is based on the electrical sensing zone (ESZ) or the Coulter principle, was used to measure the size distribution of Asian dust. Coulter Multisizer analysis provides high-resolution size measurements of water-insoluble aerosol particles (WIPs) and the number concentration at each size bin. Aerosol filter sampling was conducted at four sites in Japan during spring 2003. The measured volume size distributions fit fairly well with a lognormal distribution. The results show that the WIP size distributions of the same Asian dust air mass varied at each sampling site and the volume mode diameter at the sites reduced from west to east. The derived volume mode diameter ranged from 1.4 to 2.2 mu m and was comparatively smaller than those in previous studies on Asian dust. This can be explained by the possible internal mixing of Asian dust with other components and by the breaking of particles and dispersion of aggregations by ultrasonification during extraction. The analysis method was improved by washing the aerosol particles collected on a filter using a magnetic stirrer, instead of an ultrasonic cleaner. As a result, the WIP size distribution can be measured in the range of 1-10 mu m. The measured mode diameters were 2.6-3.1 and 4.3-5.6 mu m in 2 Asian dust phenomena at Kofu, Japan, in 2004. It is demonstrated that the Coulter Multisizer method can furnish detailed information regarding the spatial and temporal variations in the mineral dust size distribution.

DOI： 10.1175/JTECH1965.1

Web of Science

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

Optical observation around near UV spectral region potentially enables us to retrieve light absorbing features of aerosol, such as type as well as optical thickness. We analyzed near UV observation data to identify haze properties around Japan in the autumn of 2003, using Global Imager onboard Advanced Earth Observing Satellite-II (ADEOS-II/GLI), which has 380nm and 400nm window channels. At the same time, we had optical observation, such as a ground-based LIDAR measurement and a shipborne skyradiometer measurement, so as to retrieve vertical profile, particle sphericity, particle size distribution, and optical thickness of the haze.Based upon the three kinds of analyses with remotely sensed data, such as satellite, LIDAR, and skyradiometer, we have the following characteristics of the haze: little UV absorbing, of optical thickness 0.5 (around 500nm), within lower boundary layer (less than around 1km a.s.l.), and of spherical and fine particles (0.2 mu m in radius).We also have some direct sampling measurements onboard Research Vessel Shirase, such as integrated nephelometer, particle soot/absorption photometer, and optical particle counter, so as to identify optical and microphysical properties of the haze as well as chemical composition analyses. The results of the surface direct sampling showed the dense haze dominantly consisted of smaller (0.2 mu m in radius) and sulfate particulates, which is consistent to the remotely sensed results.Backward trajectory simulations also indicate that the hazy air mass had arrived from/through some mega cities over East Asia. Further, we are going to investigate the consistency between optical, microphysical, chemical, and dynamical aspects using a chemical transport model.

DOI： 10.1117/12.693033

Web of Science

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

This study shows match-up analysis of chlorophyll-a concentration in coastal area in Upper Gulf of Thailand. An applicability of atmospheric correction are investigated in turbid area. When a suspended matter concentration is over 7 g/m(3) in a mouth of Bangpakong river, atmospheric correction was failed, then chlorophyll-a concentration could not be estimated. Three algorithms which are MODIS (Moderate Resolution Imaging Spectroradiometer) standard, neural network for GLI (Global Imager) and regional empirical algorithm are compared using match-up data set. The regional algorithm has better correlation than other algorithms and its RMSE was minimum in three algorithms. MODIS standard algorithm has good performance in higher than 1 mg/m(3), however, CHL was overestimated in lower concentration.

DOI： 10.1117/12.693999

Web of Science

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：(MISC) Introduction and explanation (international conference proceedings)  

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

Language：English  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

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

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

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

DOI： 10.2151/jmsj.81.151

Web of Science

Language：English  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

A radiative transfer model for a coupled atmosphere-ocean system was developed for satellite remote sensing of coastal pollution to estimate water-leaving radiance from polluted sea surfaces. The optical properties of suspended substances in the ocean such as phytoplankton (Skeletonema costatum and Heterosigma akashiwo), detritus, submicron particles, and inorganic particles were measured or estimated. The equation of radiative transfer in the coupled atmosphere-ocean system was solved by using the invariance imbedding method. The water-leaving radiance in clear and Case Il waters, turbid waters with soil particles, and red tide waters, were calculated. It was possible to estimate the soil particle concentration of water by using the ratio of the upward radiance at different wavelengths with a high resolution sensor for the land like the Landsat TM. However, estimating the red tide phytoplankton concentration using Landsat TM was difficult, because the water-leaving radiance varies little with phytoplankton concentration, and is affected by assumed amounts of detritus.

Web of Science

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：(MISC) Introduction and explanation (international conference proceedings)  

Language：English   Presentation type：Poster presentation  

Venue：Incheon, Korea  

Audience： General

Type：Lecture

Audience： Schoolchildren,　Guardians

Type：Visiting lecture

Audience： High school students

Type：Visiting lecture

Audience： General

Type：Lecture

Audience： High school students

Type：Visiting lecture

Audience： High school students

Audience： General

Type：Lecture

Audience： General

Type：Lecture

Audience： General

Type：Lecture

Audience： General

Type：Lecture

Audience： General

Type：Lecture

Audience： Company

Type：Research consultation

（製品名／商品名）
偏光光散乱式粒子計測器
（支援の種類）
工業技術支援
（貢献の度合い）
ソフトウェア全般を開発している

Audience： Scientific

富士山測候所を観測や教育など様々な目的に活用する