ISSN:0143-1161    

DOI:10.1080/01431169408954221

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The problem addressed in this work is computer assistance to numerical image processing systems. The method used is the implementation of a collection of exercises which form a pedagogical simulation of numerical image processing. The implemented software has two parts: a set of exercises implementing a pedagogical strategy and a user interface. These exercises familiarise the user with the manipulation of numerical data, and introduce him to the working principles of most numerical image-processing systems.

ISSN:0143-1161    

DOI:10.1080/01431169408954222

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Weapplied airborne thermal remote sensing to a wet soil test area in the French region of Limousin for which a 1:10000 scale soil map already exists. Specific types of soil can be recognized and delimited on the thermographs. The flight took place on 21 February 1985 at 10:00 local time, following a four-day cold period. The radiometer was used with a 10·5–12·5νm channel. Apparent temperatures were higher on shallow soils (developed on gneissic and diorite rocks) and hydromorphic soils than on well-drained soils on slopes. Measurements of the ground soil thermal properties allow Ihermal inertia 10 be calculaled for each type of soil; in addition they enable the verification that both deep wet soils with high heat capacities and pebbly soils with high conductivities have higher Ihermal inertias. The differences in Ihermal inertia explain the observed differences in apparent temperature for a flux variation corresponding to that which prevailed during Ihe days preceding the flight.

ISSN:0143-1161    

DOI:10.1080/01431169408954223

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This study employs data from the airborne Thermal Infrared Multispectral Scanner (TIMS) to measure thermal (i.e., longwave) energy responses, emitted or upwelling, from discrete surfaces that are typical of the city landscape within Salt Lake City, Utah, over a single diurnal time period (i.e., a single day/night-time sequence). These data are used to quantify the disposition of thermal energy for selected urban surfaces during the daytime and night-time, and the amount of change in thermal response or flux recorded between day and night. An analysis is presented on the thermal interrelationships observed for common urban materials for day, night, and flux, as identified from the TIMS data through the delineation of discrete surface type polygons. The results from the study illustrate that such factors as heat capacity, thermal conductivity, and the amount of soil moisture available have a profound impact on the magnitude of thermal energy emanating from a specific surface and on the dynamics of longwave energy response between day and night.

ISSN:0143-1161    

DOI:10.1080/01431169408954224

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431169408954225

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The results of the first comprehensive limnological experiment conducted in Lake Onega in the summer of 1989 are presented. The concurrent spacebornc observations (Cosmos-l870 SAR), airborne surveys (visual observations and IR radiometry), and shipborne observations (visual observations, thermal and optical water characteristics), made it possible to establish the presence of vast regionsof phytoplankton in the lake. It is shown that the activity of phytoplankton may change water surface conditions, thus causing strong radar signal contrasts.

ISSN:0143-1161    

DOI:10.1080/01431169408954226

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Twenty-one NOAA-9 AVHRR satellite images of the southern Great Barrier Reef, spanning the period from June 1986 to September 1988, were examined for sea surface temperature patterns in order to trace circulation within this bathymetrically complex area. Our findings are in general agreement with the few field studies of this region. The East Australian Current tended to flow outside the reefs along the shelf break until it entered the Capricorn Channel, where it either meandered westward along the narrowing shelf, adhering closely to the slope contours, or flowed directly southward. It then impinged upon the shelf break, near Fraser Island, where it bifurcated to produce a southward continuation of the current, and a cyclonic eddy within the Capricorn Channel. Cool water, which commonly occurred over the shelf between Fraser Island and Cape Clinton, has probable significance for biological production within the adjacent Capricorn/Bunker Reefs of the Great Barrier Reef Marine Park. Interpreted as a response to upwelling, this cool water may be the result of: I. the combined effect of tidal pumping and coastal trapped waves; 2. effects of the longshore wind component; or 3. topographically-induced upwelling of slope waters due to flow of the East Australian Current along the continental shelf break. The evidence for each of these possible factors is discussed.

ISSN:0143-1161    

DOI:10.1080/01431169408954227

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Most of the atmospheric correction methods proposed in the literature are not easily applicable in reaJ cases. The most sophisticated models frequently require inputs which are not commonly available, whilst traditional simple dark object subtraction techniques do not generally give real reflectance values. In the present work an atmospheric correction method applicable to Landsat-TM data is described, which requires only inputs that are commonly available and the presence in the imaged scenes of some dark surfaces in TM bands 1 (blue) and 3 (red). The method consists of an inversion algorithm based on a simplified radiative transfer model in which the characteristics of atmospheric aerosols are estimated by the use of the path radiance in two TM bands rather than a priori assumed. On the basis of this information, which is crucial for determining the atmospheric properties, the retrieval of real reflectances from TM images is possible. The method can be applied to all TM scenes in which some dark points can be realistically supposed to be present, which is particularly advantageous in retrospective studies. Several TM scenes taken from different landscapes and in different seasons were corrected using the model. The reflectance values found were tested against ground measurements and compared with data from the literature. The results show a substantial improvement in the accuracy of the reflectance estimates with respect to estimates without atmospheric correction. Given some care in the identification of dark values, the relative error in actual reflectance retrieval is always rather low (≅10–20 per cent); this error can be considered acceptable for most practical applications.

ISSN:0143-1161    

DOI:10.1080/01431169408954228

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In many areas of northern Europe rapeseed is the only botanical species for vegetable oil production. Rapeseed in many areas has become the most dominant breakcrop stabilizing rotations with a high proportion of cereals. The area sown to the crop has expanded dramatically in the last 20 years, with the Scottish crop rising from less than 100ha in 1980 to over 40000 ha in the 1990s.

ISSN:0143-1161    

DOI:10.1080/01431169408954229

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Change-vector analysis in multi-temporal space is a powerful tool to analyse the nature and magnitude of land-cover change. The change vector compares the difference in the time-trajectory of a biophysical indicator for successive time periods. This change detection method is applied to three remotely-sensed indicators of land-surface conditions—vegetation index, surface temperature and spatial structure—in order to improve the capability to detect and categorize subtle forms of land-cover change. It is tested in a region of West Africa, using multi-temporal Local Area Coverage imagery obtained by the Advanced Very-High Resolution Radiometer on NOAA-9 and NOAA-II orbiting platforms. The three indicators show a low degree of redundancy and detect different land-cover change processes, which operate at different time scales. Change vector analysis is being developed for application to the land-cover change product to be produced using NASA's Moderate-Resolution Imaging Spectroradiometer instrument, scheduled for flight in 1998 and 2000on EOS-AM and -PM platforms.

ISSN:0143-1161    

DOI:10.1080/01431169408954230

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor