This paper investigated the relation between the coefficients of an estimation function for the sea surface temperature and the standard deviation of errors by the split window method of remote sensing. "A set of error ellipses" is defined to a validation data set. It describes contours of the standard deviation of errors in the γ-β plain where γ and β are the coefficient pair of the estimation function. The, standard deviation of errors remains small when a coefficient pair exists near the center of error ellipses along their long axes. By using Mutsu Bay observation data sets, the coefficient pairs of published estimation functions were examined and a sub-optimal coefficient pair is proposed to provide smaller, but not necessarily smallest, standard deviations of errors to various observation data sets.
A non-destructive measuring method for estimating leaf water content was applied for soybean and sweet potato using a spectrophotometer. In this paper, we tried to find the most effective band and experimental equations suitable for estimating leaf water content of soybean and sweet potato. 1) The most effective wavelength for estimating leaf water content of soybean rFukuyutakaj is 1496 nm. The regression equation is WSB=-0.352/R1496nm+22.9, where WSB is leaf water content (H2Omg/cm2) and R1496nm is spectral reflectance (%) at 1496 nm. In this case, the multiple correlation, coefficient and the SEE (Standard error of estimate) are 0.937 and 0.574 respectively. 2) The most effective wavelength for estimating leaf water content of sweet potato [Benikomachi] is 1384 nm. The regression equation is WSP=-0.609×R1384nm+47.2, where WSP is leaf water content (mg/cm2) and R1384nm is spectral reflectance (%) at 1384 nm. In this case, the multiple correlation coefficient and the SEE are 0.944 and 1.875 respectively.
In this paper, a multiple scattering analysis of the reflectance and linear polarization image data measured by the airborne POLDER sensor is done. Assuming an atmosphere-ocean system with a Cox-Munk type reflecting sea surface, the theoretical reflectance and linear polarization are computed by the adding and doubling method for several different atmospheric models. The simulated reflectance and polarization images based on the multiple scattering computations are presented. By comparing the theoretical results with the observational data (Medimar data), we find that many conspicuous features in the observed reflectance and linear polarization images can be explained by the sea surface reflection, together with multiple scattering within the atmosphere. Our investigation discloses several important new findings as follows: 1) A conspicuous partial elliptical pattern found in the forward scattering direction in the measured reflectance image is mainly due to the specular reflection by the rough sea surface. 2) Two distinct local polarization minimum points, located symmetrically against the principal plane in the backward scattering direction in the measured polarization image, seem to be produced by an unknown kind of coupling effects between the atmosphere and the rough sea surface. It is shown that neither the rough ocean surface alone nor the atmospheric multiple scattering alone can explain such eye-ball like polarization minimum features. 3) We find the oceanic type aerosol model is not an appropriate aerosol model for Medimar data. On the other hand, the Junge type aerosol model with 3<v<5 is able to show similar polarization features as those in the observation.
We conducted experiments on detecting intentionally oil polluted areas using the C-band Synthetic Aperture Radar on the European Remote Sensing Satellite-1 in November 1991 and in October and November 1992. Intentionally polluted areas were produced by spilling oleyl alcohol from a small ship in the Pacific Ocean about 100 km off the coast of Japan. Sea truth data were collected by both a research vessel and the small ship which is used to spill the alcohol. The ERS-1 SAR images were processed by NASDA. The intentionally polluted areas appeared as dark patch area on the SAR image. This is because slick damps surface capillary waves and makes ocean surface smooth, and slick appears as dark patch area in the SAR image. The intentionally polluted areas were clearly detected by ERS-1 SAR under various wind speeds of less than 11m/s. While we expected the damping decreases as the wind speed increases, the maximum damping of the scattered power was nearly the same (4 to 5 dB) for wind speeds of less than 11m/s. This may be because of the small incidence angle of 23° where the effect of quasi-specular scattering still remains. However, the ERS-1 SAR did not detect the intentionally polluted areas when the wind speed was 13.7m/s. Although we cannot state any definite reasons, we suppose that intentionally polluted areas may have been scattered out by the strong wind and could not make damp surface capillary waves produced by strong wind. We need further analysis and experiment under strong wind conditions.
The rice crop in the northern part of Japan suffered from cold-weather damage seriously in 1993. MOS-1/MESSR data acquired on September 2, 1993 was analyzed to obtain a geographical distribution map of the rice yield in the central Hokkaido. Since sterility does harm to the rice yield, there is strong correlation between the extent of sterility and the chlorophyll content of the leaves during the ripening period. Therefore, we can estimate the yield from rice canopy reflectance of the light in the red region of MESSR. For extracting paddy fields, the Landsat TM data acquired on July 8, 1993 was also used. MESSR image of paddy fields was superimposed on the administrative district mesh map based on the Digital National Land Information of the Geographic Survey Institute. The statistical reports of agriculture, forestry and fisheries in Hokkaido were used as ground truth data. There is a close relation between digital number of MESSR band 2 and yields of five subprefectures reported officially in December 1993. A simple linear regression model derived from these data was found useful to estimate distributions of yields, and application of logistic curve was also attempted. Estimated yields in 1 km grid were averaged to make the grid map of rice yield distribution.
In 1986 the general assembly of International Council of Scientific Unions (ICSU) decided to establish "International Geosphere-Biosphere Programme: A Study of Global Change (IGBP)" for period of 10 years from 1990. Following 4 study areas were identified to be significant by ICSU Special Committee; terrestrial biosphere-atmospheric interaction, marine biosphere atmosphere interaction, biospheric aspect of hydrological cycle, effect of climate change on terrestrial ecosystem. In addition working groups on the following 4 areas were established; global geoshpere-biosphere modeling, data management and information sysmtems, techniques for extracting environmental data of the past, geosphere biosphere observatories. Later review on the study areas resulted in the establishment of following core projects. International Global Atmospheric Chemistry (IGAC), Global Change and Terrestrial Ecosystems (GCTE), Biospheric Aspects of the Hydrological Cycle (BAHC), Land-Ocean Interactions in the Coastal Zone (LOICZ), Joint Global Ocean Flux Study (JGOFS), Past Global Changes (PAGES). Two other core projects are being developed for possible acceptance. Land Use/Cover Changes (LUCC), Global Ocean Euphotic Zone Study (GOEZS). In addition 3 activites of interdisciplinary and common interests are operational. Global Analysis, Interpretation and Modeling (GAIME). IGBP Data and Information System (IGBP-DIS), Global Change System for Analysis, Research and Training (START). Realizing the importance of the project, Japan first made preliminary study funded by Ministry of Education in 1988, which was later taken over by Science Council of Japan and national committee was organized in Science Council of Japan, counterpart of ICSU. After two years studious effort and coordination with other groups in Science Council of Japan, Recommendation for Implementation of IGBP was submitted to prime minister from President of Science Council of Japan which was forwarded to all ministers. The committees for all projects of ICSU have been organized in Science Council of Japan to promote implementation of IGBP.