摘要:

Airborne thermal imagery of a large varying-terrain commercial barley field was acquired over a full growing season. The data were analysed to determine temperature variability within the field and the percentage of area within various size instantaneous fields of view (ifovs) that would be within ±1, ±2, ±3 and ±5°C of the mean. There appears to be no great advantage in utilizing a small ifov instead of a large one for remote sensing of crop temperature.

ISSN:0143-1161    

DOI:10.1080/01431168108948357

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Integration of Landsat multispectral scanner (MSS) data with 30 m U.S. Geological Survey (USGS) digital terrain data was undertaken to quantify and reduce the topographic effect on imagery of a forested mountain-ridge test site in central Pennsylvania. Four methods for reducing the topographic effect were compared; band ratioing and three radiance models. Band ratioing did not eliminate the topographic effect due to the lack of variation in MSS4 radiances. Of the three radiance models applied to the data, the lambertian and modified lambertian models increased the topographic effect. The non-lambertian model considerably reduced (86 per cent) the topographic effect in the Landsat data. The study demonstrates that high quality digital terrain data as provided by the USGS can be used to enhance the utility of multispectral satellite data.

ISSN:0143-1161    

DOI:10.1080/01431168108948358

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The use of Landsat 70 mm film images for the production of land use maps of Hong Kong, a small territory of 1061 km2in area, was evaluated according to their planimetric accuracy and the accuracy of land use interpretation. Land use maps were produced at a scale around 1:250 000 with the aid of a Fairey additive viewer and at a scale of 1:88 500 through manual interpretation. Finally, an urban land use map at a scale of 1:25 000 was generated with a computer-assisted method of analysis of the Landsat data. It was concluded that these land use maps were all of an acceptable planimetric (±400m) and semantic accuracy (89 per cent), especially if a high level of generalization was intended. The computer-assisted method of analysis permits more detailed urban land use information to be extracted, but with an accuracy of only 69 per cent.

ISSN:0143-1161    

DOI:10.1080/01431168108948359

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The effects of off-nadir viewing, canopy geometry and density, solar zenith angle, and atmospheric condition on the radiance and normalized difference index (ND) of a grass canopy as viewed from a satellite are examined via simulation techniques. Two wavelengths, 0·68 and 0·80 μm, are considered. Results indicate that off-nadir viewing effects are more pronounced in the red than in the I.R., but that the ND index tends to eliminate much of the variability seen in the individual bands. The magnitude of off-nadir viewing effects is also shown to be a function of canopy geometry. Overall variability of the ND tends to decrease with increasing biomass at given sun and view angles, but increases with increasing solar zenith angles. Atmospheric haze masks useful surface information by intensifying scattering effects.

ISSN:0143-1161    

DOI:10.1080/01431168108948360

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A simple analysis method is provided to locate the point of maximum sea surface glitter for a scanner on a sun-synchronous orbit. The method is easily extended to any type of scanning system. Sun glint avoidance methods are discussed.

ISSN:0143-1161    

DOI:10.1080/01431168108948361

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Resource management agencies are interested in knowing when and how satellite data can be effectively used to monitor environmental change and what information can be expected from remote sensing techniques. In this paper the procedures that might be followed in applying the complementary methods of band ratioing and post-classification change detection to monitor a large remote area are outlined. Examples from research in the Peace-Athabasca Delta are used to illustrate the procedures and expected results.

ISSN:0143-1161    

DOI:10.1080/01431168108948362

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948363

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948364

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948365

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor