Prediction of the runoff from a mountainous snow covered area is one of the most important problem in the hydrology field in order to make good use of water resources. In recent years, satellite remote sensing data by LANDSAT or NOAA have become available. If the data could provide information of the fallen snow in a wider area, they would remarkably increase computational accuracy of the snowmelt-runoff. The present paper, using a real basin as an example, deals with co-relations among the information such as reflectance of the snow in a snow-covered area obtained from LANDSAT/ MSS data, the thermal distributing on the snow-covered surface of the Earth obtained from NOAA/AVHRR data, and the condition of snow melting. The following properties become evident after examing the result of analysis. (1) It is shown that the reflectance of the snow-covered surface decreases in proportional as the average incidence angle of solar rays. (2) Along as contour line, the reflectance of the snow surface does not keep in uniform condition. (3) It is shown that the reflectance of snow decreases with seasonal change. Also, the decreasing ratio varies with topographical feature. (4) It is shown that the pattern of temperature distribution depends upon both the wind direction and the direction of the solar rays against the snow-covered surface influence.
The remote sensing of Arctic sea-ice by microwave sensors is an important and useful subject for Canada. Simultaneous observation data of Arctic sea-ice by HH-and HV-polarized fanbeam doppler scatterometer operating at 13.3GHz over incidence angles extending from nadir to 60°, 19.4 GHz H-polarized radiometer at a fixed incidence angle of 45°and RC-10 aerial photographs with overlapping X-and L-band SAR imageries were acquired in March 1979 in the Beaufort Sea and in the Eastern Arctic in April 1979 in the SURSAT project of Canada. This paper reviews briefly the classification of various types of sea-ice by the definition of WMO and physical properties of sea-ice. Outlines of the airborne experiments by the CCRS Convair 580 with explanations of scatterometer and radiometer are also reviewed. Microwave signatures for each sea-ice class are presented in terms of the dependence on incidence angle of HH-and HV-polarized scattering coefficients as well as their H-polarized microwave emissivities at the incidence angle of 45°.Classifications of various types of sea-ice are performed at the incidence angle of 45°by the combination of HH-and HV-polarized scattering coefficients and H-polarized microwave emissivities. It is shown that simultaneous scattering coefficient and emissivity measurements can yield a useful sea-ice classification.
In order to make good advancement in reproducibility, quantitativity and accuracy, we have developed a processing system which is composed of the following three main elements. 1) Each photographic processing is analyzed elaborately and simulated with the image analyzing system CIC 10 on the basis of Jones tone reproduction diagram. Then suitable package programs are developed. 2) Exposure is made by the computer controlled contact printer (photographic analyzing processor) provided with programs for various photographic processing. 3) Development and fixation of photographic materials are made by three kinds of automatic processors. In this report, tone control processing is examined mainly from the following two methods ; 1) control by effective exposure and density ranges, 2) control by contrast, and good results are obtained. Also the various compound processing systems in which tone control processing is combined with density slice, pseudo-color, hybrid pseudo-color and tone line processing are fully examined and the compound processing system suitable for analyzing LANDSAT imageries is developed. In every case it is confirmed that practically processed results are well consistent with the simulated results and the system is very useful for various purposes. Moreover LANDSAT MSS imageries of Ariake Sea are proccessed and analyzed by these procedures.
This paper refers the feasibility of Landsat MSS data for forest type classification. Study area was chosen at Tango penisula of central Honshu island in Japan. Forest type classification was performed using two season combined Landsat MSS data after the ratioing process between two adjacent spectral bands. The reasons to use this sort of data are as follows ; 1) Value of Landsat MSS image varies with the ground slope and direction. To eliminate this slope effect in the data analysis, the ratioed value between two adjacent bands can be applicable. 2) Spectral reflectance of leaf varies with season. Combination of two seasonal Landsat MSS data before and after autumn tints will cause a distinct separation between an ever green leaf and a deciduos one. Requirements for the two-season combined Landsat MSS data are as follows ; 1) Line noise in the raw Landsat MSS data seen like as "stripe on the cloth" due to 6 detectors, should be reduced as low as possible. Radiometrically uniform MSS data within about 0. 2 in quantum level were obtained by the level matching method using cumulative frequency distribution. 2) There needs rigorous registration between two seasonal Landsat imageries. Using 15 ground control points around the study area, a registration accuracy with about one pixel, i.e., 57 meters in standard deviation was obtained in the two Landsat imageries and the corresponding 1:50, 000 topographical maps. Comparison of the classified results with the forest statistics gives the following facts; Classification errors of each forest type became about 7% in Conifer to 13% in Hardwood in average for each local government area.
MSS's aboard Landsat 2 and 3, which retired from operational service on March 31, '83, experienced line start anomaly over several periods of months to a year in their operation. Line start anomaly is a trouble wherein start timing of data sampling within each mirror scanning is delayed and the western 27 percent of the data line is lost. In image, this late start data line appears displaced from normal data lines. The image displacement degrades the image usefulness greatly. Line start anomaly also affects the calibration data which are generated following the image data. As the frequence of the line start anomaly occurence increases, calibration data begin to be delayed with respect to the end of the image data and finally reach to the maximum dislocation where the latter part of the calibration data is damaged by the next image data line. Damaged calibration data result in anomalous radiometric correction, if they are used. In an attempt to recover the line start anomaly data, Landsat ground stations in the world devised various methods which include new hardware installation and software modification. But the most of the methods have drawbacks in that they can not cope with the damaged calibration data and that a buffer memory is required, etc. A method proposed in this paper is the one adopted at Earth Observation Center (EOC), Japan. The method eliminates the aforementioned shortcomings and has proven itself very effective through its practice at EOC. This paper first introduces the mechanism of the line start anomaly and various recovery methods adopted by other ground station and then give a comparison on advantages and disadvantages of each method. Finally the description of the Japanese method is presented and some examples of its practice are shown.