Engineering Degree Program in China - Environmental Remote Sensing

1. Introduction

Environmental Remote Sensing is a remote sensing technology for the purpose of detecting the phenomenon and its dynamics of the earth's surface environment. It can be understood as a synonym for all remote sensing activities involving resources, atmosphere, ocean, environment and ecology. Remote sensing activities aimed at the detection and study of environmental pollution and the spatial distribution and time scale, nature, development dynamics, effect and harm, in order to take environmental protection measures or formulate ecological environment planning, which are although on the list of environmental remote sensing, generally not called as the environmental remote sensing. Remote sensing has the characteristics of multi-level, multi temporal and multi function and multi topic in data acquisition; has the characteristics of multi-source data processing, comprehensive analysis, multidisciplinary and multidimensional dynamic monitoring and multipurpose applications.

2. Observation Methods

Environmental remote sensing obtains remote sensing image of environmental pollution by two methods: photography and scanning. Photography has black-and-white panchromatic photography, black-and-white infrared photography, natural color photography and color infrared photography. Color infrared photography is the best, the obtained image of the environment pollution is clear, can identify the advantages and disadvantages of the growth of a variety of crops and other plants after the pollution. The scanning is mainly multi spectral scanning and infrared scanning, which is used to observe the water pollution and thermal pollution of rivers, lakes, reservoirs, and the sea. The influence range and diffusion characteristics of waste water discharging into the water body can be found on the infrared scanning image.

Large-areas synchronization can be realized through the aerial and space remote sensing to monitor environmental pollution, which is impossible by other means. The environmental satellite can repeat ground imaging every certain period of time, conduct continuous monitoring, to grasp the dynamic changes of environmental pollution, and forecast the development trend of pollution, which is the unique feature of remote sensing mean.

3. Environmental Satellite

The mission of environmental satellite is to provide global or local environment image, so as to obtain the quantitative data of various environmental factors of the earth. The data is recorded every certain period of time, with dynamic nature. The environmental satellite can provide the data collected by the regional central receiving center, and the data is gathered by the regional reception center to provide the relevant departments to use.

There are two kinds of environmental satellite flight orbits. One is sun synchronous circular orbit near the earth pole, which is used by the land satellite. The track is as close as possible to the earth pole and is round, can guarantee to pass above the observation points at the same time, in order to have the same lighting conditions and sufficient solar energy, with better access to global environmental image. Another is earth synchronous circular orbit and some meteorological satellites use this orbit. The satellite orbits in the equatorial plane of the earth with the same direction as the direction of the earth's rotation, taking 24 hours to finish a circle around the earth, and synchronization with the earth's rotation. This kind of satellite is relatively static at a point on the earth's equator, and conducts continuous monitoring of the large area of the earth's environment.

4. Application

1) Atmospheric environmental remote sensing: weather satellite not only provides satellite cloud pictures for weather research, but also monitors the sediment turbidity currents of river discharge and floating oil on the sea, using land satellite images to analyze dust pollution in factories.

2) Terrestrial environmental remote sensing: a large area of water quality variation is also reflected in the terrestrial satellite.

3) Marine environment remote sensing: the ocean satellite can monitor many kinds of pollution condition of the sea surface.

4) Vegetation ecological remote sensing. Vegetation ecological survey is an important application field of remote sensing.

5) Soil remote sensing. Soil is a resource of agricultural productivity which covers the surface of the earth. It is also related to many environmental problems.