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An algorithm based on CO2 slicing, which has been used for cirrus cloud detection using thermal infrared data, was developed for high-resolution radiance spectra from satellites. The channels were reconstructed based on sensitivity height information of the original spectral channels to reduce the effects of measurement errors. The selections of the reconstructed channel pairs were optimized for several atmospheric profile patterns using simultaneous studies assuming cloudy sky. That algorithm was applied to data by the Greenhouse gases Observing SATellite (GOSAT). The results were compared with those obtained from space-borne lidar instrument onboard Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Monthly mean cloud amounts from the slicing generally agreed with those from CALIPSO observations despite some differences caused by surface temperature biases, optically very thin cirrus, multilayer structures of clouds, extremely low cloud tops, and specific atmospheric conditions. Comparison of coincident data showed good agreement except some cases and revealed that the improved slicing method is more accurate than the traditional slicing method. Results also imply that improved slicing can detect low-level clouds with cloud top heights as low as approximately 1.5 km.

The polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. For this reason an increasing number of polarimetric observations are performed from space, from the ground and from aircraft. Polarized radiative transfer models are required to interpret and analyse these measurements and to develop retrieval algorithms exploiting polarimetric observations. In the last years a large number of new codes have been developed, mostly for specific applications. Benchmark results are available for specific cases, but not for more sophisticated scenarios including polarized surface reflection and multi-layer atmospheres. The International Polarized Radiative Transfer (IPRT) working group of the International Radiation Commission (IRC) has initiated a model intercomparison project in order to fill this gap. This paper presents the results of the first phase A of the IPRT project which includes ten test cases, from simple setups with only one layer and Rayleigh scattering to rather sophisticated setups with a cloud embedded in a standard atmosphere above an ocean surface. All scenarios in the first phase A of the intercomparison project are for a one-dimensional plane–parallel model geometry. The commonly established benchmark results are available at the IPRT website ( http://www.meteo.physik.uni-muenchen.de/iprt ).

Based on a vector radiative transfer model of the atmosphere-ocean system, the influence of oceanic components on radiation processes, including polarization effects, was investigated in the wavelength region ranging from 0.380 to 0.865 μm. The components considered were phytoplankton, inorganic suspended material (sediment), and colored, dissolved organic matter. Due to their important roles in oceanic radiation processes, the sensitivity of the bidirectional reflectance to the rough ocean surface, represented by the wind velocity 10 m above the ocean surface, and aerosol, were taken into account. The results demonstrated that both radiance and polarized radiance just below the ocean surface were sensitive to the change of the concentrations of the considered components, while the dependence of polarized radiance on the observation geometry was more sensitive than radiance. Significant differences in the specular plane existed between the impacts of the phytoplankton and sediment on the degree of polarization just above the ocean surface at 670 nm. At the top of the atmosphere (TOA), polarization was relatively insensitive to changing concentrations of ocean particles at longer wavelengths. Furthermore, the radiance at the TOA in the solar plane was more sensitive to the aerosol optical thickness than wind velocity. In contrast, wind velocity strongly influenced the radiance at the TOA in the sun glint region, while the polarization degree showed less dependence in that region. Finally, a nonlinear optimal inversion method was proposed to simultaneously retrieve the aerosol and wind velocity using radiance measurement.

In this paper seven vector radiative transfer codes are inter-compared for the case of underlying black surface. They include three techniques based on the discrete ordinate method (DOM), two Monte-Carlo methods, the successive orders scattering method, and a modified doubling-adding technique. It was found that all codes give very similar results. Therefore, we were able to produce benchmark results for the Stokes parameters both for reflected and transmitted light in the cases of molecular, aerosol and cloudy multiply scattering media. It was assumed that the single scattering albedo is equal to one. Benchmark results have been provided by several studies before, including Coulson et al. [22], Garcia and Siewert [7,8], Wauben and Hovenier [10], and Natraj et al. [11] among others. However, the case of the elongated phase functions such as for a cloud and with a high angular resolution is presented here for the first time. Also in difference with other studies, we make inter-comparisons using several codes for the same input dataset, which enables us to quantify the corresponding errors more accurately.

Remote sensing of aerosol from space is a challenging and typically underdetermined retrieval task, requiring many assumptions to be made with respect to the aerosol and surface models. Therefore, the quality of a priori information plays a central role in any retrieval process (apart from the cloud screening procedure and the forward radiative transfer model, which to be most accurate should include the treatment of light polarization and molecular-aerosol coupling). In this paper the performance of various algorithms with respect to the of spectral aerosol optical thickness determination from optical spaceborne measurements is studied. The algorithms are based on various types of measurements (spectral, angular, polarization, or some combination of these). It is confirmed that multiangular spectropolarimetric measurements provide more powerful constraints compared to spectral intensity measurements alone, particularly those acquired at a single view angle and which rely on a priori assumptions regarding the particle phase function in the retrieval process.

A vector radiative transfer model has been developed for a coupled atmosphere–ocean system. The radiative transfer scheme is based on the discrete ordinate and matrix operator methods. The reflection/transmission matrices and source vectors are obtained for each atmospheric or oceanic layer through the discrete ordinate solution. The vertically inhomogeneous system is constructed using the matrix operator method, which combines the radiative interaction between the layers. This radiative transfer scheme is flexible for a vertically inhomogeneous system including the oceanic layers as well as the ocean surface. Compared with the benchmark results, the computational error attributable to the radiative transfer scheme has been less than 0.1% in the case of eight discrete ordinate directions. Furthermore, increasing the number of discrete ordinate directions has produced computations with higher accuracy. Based on our radiative transfer scheme, simulations of sun glint radiation have been presented for wavelengths of 670 nm and 1.6 μm. Results of simulations have shown reasonable characteristics of the sun glint radiation such as the strongly peaked, but slightly smoothed radiation by the rough ocean surface and depolarization through multiple scattering by the aerosol-loaded atmosphere. The radiative transfer scheme of this paper has been implemented to the numerical model named Pstar as one of the OpenCLASTR/STAR radiative transfer code systems, which are widely applied to many radiative transfer problems, including the polarization effect.

The Greenhouse Gases Observing Satellite (GOSAT) was launched on January 23, 2009, to monitor global atmospheric levels of CO2 and CH4 from space. GOSAT started initial operation of its instruments after an initial satellite system check. Although the radiant data obtained by the GOSAT instruments are currently in the preliminary stages of calibration and validation, the spectral absorption features of CO2 and CH4 are clearly identifiable. An initial retrieval of these gaseous concentrations was performed for measurement scenes of cloud-free conditions over land. These results showed that column-averaged dry air mole fractions of both CO2 and CH4 in the northern hemisphere were higher than those in the southern hemisphere. These latitudinal differences agree with data obtained from ground-based sources and other satellite observations; however, the absolute values of the gaseous concentrations from GOSAT data seem to have been underestimated. Calibrations as well as validation should be conducted to improve the quality of GOSAT retrievals.

To prepare conductive polymers more soluble in organic solvents and more stable to over-oxidation than polyaniline, some N-alkylanilines were electropolymerized. Several polymerizing solutions with different kinds of anions (SO42− and ClO4−) and organic solvents (acetonitrile and dimethyl sulfoxide) were employed. The anions and organic solvents were selected on the basis of the lipophilicity relationship among the poly(N-alkylaniline)s, the dopant anions and the organic solvents. The bell-shaped dependence of the conductivity on the N-alkyl chain length of the poly(N-alkylaniline)s was first observed for the poly(N-alkylaniline)s prepared from acetonitrile solution, and the highest conductivity of 1.0×10−3 S cm−1 was obtained for SO42−doped poly(N-n-heptylaniline). The dependence of the conductivity on the alkyl chain length of poly(N-alkylaniline)s was explained by the lipophilic affinity of the organic solvents for the poly(N-alkylaniline)s.

Transparent Al2O3 films with high gas barrier properties were deposited on a PET film substrate by a web coating method using an activated reactive evaporation (ARE). The web speed was 100 to 700 m/min. The thickness of the Al2O3 film was 5 to 30 nm. ARE was beneficial for two reasons. One was the enabling of sound Al2O3 formation, and the other was the smooth winding of the Al2O3 deposited PET film achieved by neutralizing the negative charges, i.e., secondary electrons resulting from electron beam radiation on the Al evaporation source. The Al2O3 coated PET film showed an excellent barrier performance of about 1 g/m2 · day for water vapor transmission and about 1.5 cm3/m2 · day · atm for oxygen transmission, respectively, and an optical transmittance near to that of the uncoated PET. Results from analyses of Auger electron spectroscopy and X-ray diffraction, and observations of transmission electron microscopy and atomic force microscopy of the Al2O3 films are also described.

[1] The Greenhouse Gases Observing Satellite (GOSAT) was successfully launched in January 2009, with the aim of providing global observations of greenhouse gases. We developed an algorithm to retrieve CO2 vertical profiles from the terrestrial radiation spectra at 700–800 cm−1 and assessed its validity. For this purpose, we first computed GOSAT pseudomeasurement spectra and then performed CO2 retrieval simulations using the maximum a posteriori (MAP) method, with analytical data for temperature information. Our simulations with no uncertainty in the estimates of atmospheric conditions such as surface temperature, surface emissivity, and profiles of temperature, water vapor, and ozone showed that the retrieved CO2 profiles had an accuracy of 1% above 800 hPa, with little dependence on the a priori profiles. Introducing correlations between layers in an a priori error covariance matrix was important for CO2 retrieval especially above 200 hPa. Enhancing the correlations below 800 hPa was important for CO2 retrieval there. Selecting 100 channels based on CO2 information content for all layers, 10 channels for the region above 55 hPa, and 50 channels for the region below 800 hPa was sufficient to achieve CO2 retrieval with 1% accuracy from the troposphere through the stratosphere. Our simulations with possible errors in the atmospheric conditions showed that 1% accuracy was also achieved at 600–100 hPa in every latitude region, although the retrieved CO2 concentrations probably included up to 4% positive and negative biases at 30°S–30°N above 100 hPa and at mid- and high latitudes below 600 hPa, respectively.

The Greenhouse gases Observing Satellite (GOSAT) is a Japanese satellite that is intended to observe CO2 concentration from space and to contribute to advancement of research of the source/sink estimation of CO2. The GOSAT main sensor is a Fourier Transform Spectrometer (FTS) named "TANSO-FTS", which covers a wide terrestrial radiation spectrum including CO2 absorption bands at 1.6 μm, 2.0 μm, and 15 μm. The former two bands are used to estimate columnar concentration of CO2; the latter is used to retrieve the vertical profile of CO2 in the upper atmosphere above about 700 hPa pressure level. In addition, another installed on the satellite is an imaging sensor that will be used to detect clouds and aerosols: Cloud and Aerosol Imager (CAT). The Center for Climate System Research (CCSR) has contracted with the Japan Aerospace Exploration Agency (JAXA) to develop an algorithm to retrieve CO2 concentration profiles from data measured by the thermal infrared (TIR) band of the TANSO-FTS sensor. We adopt the maximum a posteriori method (MAP) to retrieve the vertical profile of atmospheric parameters from thermal infrared spectra. Key techniques for retrieving CO2 concentrations are 1) reduction of temperature estimation error through channel selection, 2) optimization of the initial guess for CO2 profile based on the output from a chemical transport model (CTM), and 3) usage of data from the 1.6 μm band of TANSO-FTS as an additional constraint in retrieval of vertical profiles of CO2. Although thermal infrared spectrum data have poor vertical resolving power for CO2 concentration in the lower atmosphere, particularly in the boundary layer, we expect that CO2 amount in the lower atmosphere can be deduced by substituting the upper level concentration from the columnar concentration estimated from the 1 .6 μm band data.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Greenhouse Gases Observing Satellite (GOSAT) will be launched in 2008 for global observations of greenhouse gases such as CO 2 and methane. This study examines the feasibility of retrieving CO 2 concentrations from the infrared spectra of the GOSAT/Thermal and near infrared Sensor for Carbon Observation (TANSO)-FTS. Retrieval simulations in which the maximum a posteriori (MAP) method was applied to pseudo-spectra at 700-800 cm -1 from TANSO-FTS (CO 2 15-μm band) showed that retrieved CO 2 profiles agreed with true CO 2 profiles to within the total errors throughout the troposphere above 700-800 hPa when atmospheric conditions such as temperature used in the computation of the spectra were known. In contrast, discrepancies between retrieved CO 2 and true CO 2 concentrations increased if temperatures used in the retrieval included random errors; a random scatter of ±0.5 K caused a discrepancy that was 12 times larger at ∼750 hPa. However, appropriate channel selection based on CO 2 and temperature information could reduce the effect of temperature uncertainty on CO 2 retrievals in this spectral region: the discrepancy between retrieved and true concentrations at ∼750 hPa in the case with channel selection was about one-third of the discrepancy without any channel selection.

This study presents an analysis of atmospheric temperature and water vapor using interferometric monitor for greenhouse gases (IMG) spectrum data and its retrieval procedure. The IMG is a high-resolution infrared sensor of the Fourier transform spectrometer (FTS) type that was launched aboard the Advanced Earth Observing Satellite (ADEOS) satellite in August 1996. Upwelling infrared radiation from the Earth was measured to examine the effects of greenhouse gases in the troposphere until June 1997. In the procedure to retrieve trace gas profiles from such satellite-based FTS data, accurate information on temperature, water vapor and surface properties is essential for precise retrieval. The instrument line shape (ILS) function, which generally depends on many factors of its sensor system, must also be determined accurately. In order to estimate the optimal ILS function, the "effective optical path difference (OPD)", which is assumed in retrieval analyses, is tuned to obtain the most optimal retrieved results in comparison with the sonde data. This method was applied to IMG spectrum data.

Reducing temperature and water vapor estimation errors is indispensable for retrieving a CO 2 concentration profile or columnar amount from thermal infrared spectrum data because spectral radiance in the thermal infrared region is much more sensitive to temperature and water vapor concentration changes than it is to CO 2 concentration changes. This study presents a data analysis procedure to estimate the CO 2 columnar amount from the thermal infrared spectrum. The fi rst step retrieves the temperature vertical profile, water vapor vertical profile, and the surface temperature from spectra in the strong absorption bands of CO 2 and H 2 O. Then the spectral biases that are attributable to temperature and water vapor retrieval errors are reduced by comparing observed and synthesized radiances in the atmospheric window region. The final step estimates the CO 2 columnar amount from the corrected sp ectra of a weak absorption band of CO 2 that is located around 940 cm -1 .This method was applied to analysis of spectrum data from IMG sensor aboard the ADEOS satellite. Some preliminary results are shown. Keywords : Carbon dioxide, CO

Analytical procedure to derive the ozone concentration profile from the analysis of the high-resolution spectrum data as observed by a space FTS sensor such as Interferometric Monitor for Greenhouse gases (IMG) onboard Advanced Earth Observing Satellite (ADEOS) has been presented. In the procedure, Jacobian matrices were re-calculated for each spectrum considering the cloud top temperature in the instantaneous field of view (IFOV) of the FTS sensor. That was because these cloud parameters seriously affect the elements of the Jacobian matrices sometimes causing the change of the sign of the elements. This method has been applied to the analysis of IMG data that were observed during the northern hemispheric ozone hole like event occurred in 1997 spring. It has been found that the usage of the precise instrumental line shape (ILS) of the sensor is very important to improve the vertical resolution of retrieval by loosening the retrieval constrains.

Low temperature poly-Si TFT mass production plan has been announced recently. However, techniques for depositing poly- Si film and gate SiO2 film, which provide the possibilities of mass production including that of large- sized substrate and film characteristics to obtain satisfactory TFT characteristics simultaneously, have not yet been established. ULVAC has developed techniques that can be applied to mass production of poly-Si film and gate SiO2 film and has completed a single-substrate PECVD system called CMD-450 poly based on these techniques. Excellent repeatability of film characteristics and film thickness uniformity. The low-hydrogen concentration PECVD a-Si and TEOS-SiO2 film mentioned below were obtained by using this system.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Polyaniline was possibly doped with cresol-sulfonic acid, though it failed to electrodeposit the polymer from solutions of aniline in cresol-sulfonic acid. The presence of cresol-sulfonate anions changed the redox peaks of the polymer in thier positions and heights. Catalytic oxidation of cresol-sulfonic acid was observed on polyaniline-filmed electrodes at potentials of a limited interval.

A new perpendicular magnetic film has been developed by an evaporation method using room temperature substrates. The film is obtained by partially oxidating the Co film with the oxygen gas introduced during deposition. The film structure is a mixture of very fine Co grains and CoO phase. The obtained films have such superior perpendicular magnetic properties as H c⊥=1100 Oe, H k=5.5 kOe and 4πM s=6000 G at Co–45 at%O film composition.