A city is a regional space with a relatively dense population and concentrated human activities and resources. It always takes on new looks along with the social and economic development, which requires correspondingly in-time monitoring and analysis. The satellite RS imagery has made remarkable achievements in fields like flood combating, disaster prevention, land resources investigation, agricultural production assessment, mineral resources investigation, general survey of cities, etc. It serves as an important technical support integrated in urban planning, construction and management, and a powerful modern tool for the government to make policies and guide and reinforce city management.
The traditional means of basic info access has restrained the urban construction and management for its long cycle, high-cost and limited scope that retards the reflection of urban space development. Therefore, the application of satellite RS imagery in the modern cities’ planning and management became imperious.
Satellite RS imagery has a competitive strength over any other means in offering pinpoint and high-frequency macroscopic-environment images of the globe or extensive areas for urban planning. Jilin-1 constellation of the Changguang Satellite Technology is taken as an example:
1.10 stably running satellites in orbit, reinforced data collecting and shorter revisit cycle.
2.Up to 0.72m resolution images provide more ground truth for urban planning.
3.Customers are allowed to self-define shootings of the target zone and obtain the latest data by deploying the satellites.
With accelerated global urbanization, the unrivaled strengths of RS technology in urban modernization and scientific management are even more manifested. It has become an important technical tool and integrated part of city planning, construction and management as well as governmental decision mechanism.
1.Urban Imagery Crafting
Thematic and imagery pictures of various scales and proportions can be made from the RS data to cater to different needs of planners, constructors, administrators and decision-makers.
2.Urban Land Usage Investigation
According to different needs, investigations are carried out respectively for residential land, infrastructure land, industrial land, municipal utilities, greenbelts, waters, etc. for corresponding RS data. Maps of the current condition and historical evolution are consequently drawn and coverage, distribution, transforming and developing tendency of the different lands are automatically measured out accordingly, providing support for the city planners.
The satellite RS imagery is a quick and accurate collector of land feature parameters including the general building and residential density, which is closely linked with population density. The housing density may be applied as a variable in the researches of census and human demography, providing national census with a convenient, effective and accurate tool.
4. Air Pollution Investigation
Distribution of pollution sources and diffusion paths can be investigated upon analyzing the RS imagery traits. For example, we can directly figure out the number, distribution, type of boilers, chimneys and on-road vehicles by virtue of the images and then the correlation between them and the emission of smoke and exhaust gas.
（5）Thermal Pollution Investigation
The two culprits of urban thermal pollution are the “Greenhouse Effect” caused by the damaged ozone sphere and the “Urban Heat Island (UHI)” effect in the form of a higher urban temperature than that of its outskirts. Infrared RS is adopted to scan day and night the city’s thermal radiation. Through imagery analysis, the heat sources, the thermal field location and sphere can be identified and the UHI distribution rules and morphology can be studied. Thereby, the urban thermal environment will be scientifically planned, regulated and administered.
The standard optical static image is a standard sub-meter product collected by Jilin-1 constellation, which is corrected and calibrated by radiation and sensors. RPC models and metadata files are available in the general tiff format.
The standard luminous (nighttime) images are standard sub-meter products collected by Jilin-1 constellation, corrected and calibrated by radiation and sensors. RPC models and metadata files are available in the general tiff format.
A standard video imagery is a standard video acquired by Jilin-1 constellation, which has a resolution less than 0.9m after being processed through image stabilizing and framing. Products in both avi and mov data formats are provided.