Geosciences and Remote Sensing

REMOTE SENSING

Remote sensing can be defined as the collection of the data about an object from a distance. Humans and many other types of animals accomplish this task with an aid of eyes or by the sense of smell or hearing. Geographers use technique of remote sensing to the monitor or measure phenomena found in Earth's, biosphere, hydrosphere, lithosphere and atmosphere. Remote sensing of environment by geographers is usually done with the help of the mechanical devices known as remote sensors. These gadgets have a greatly improved ability to receive and to record information about object without any physical contact. Often, these sensors are positioned away from the object of interest by using planes, helicopters, and satellites. Most sensing devices record information about an object by measuring an object's transmission of the electromagnetic energy from the reflecting and radiating surfaces. Remote sensing imagery has many applications in the mapping land use and cover, soils mapping, agriculture, city planning, forestry, military observation, archaeological investigations and geomorphological surveying, among the other uses. For example, foresters use aerial photographs for preparing the forest cover maps, locating possible access roads, and the measuring quantities of trees harvested. Specialized photography using colour infrared film has also been used to detect the disease and insect damage in the forest trees.