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