Emerald Robinson: Hi! I'm Emerald Robinson, and in this What Is video, we'll try to answer the question, what is remote sensing? Remote sensing is any technique used to gather information about an object that does not require touching the object. Remote sensing can be done with devices either on the ground, or on ships, planes, or even satellites.
There are two parts of remote sensing; first, devices record radiation like light or heat from an object or area, and second, this data is analyzed to determine what it means. For simplicity, we can divide all of the devices used in remote sensing into two groups.
In passive remote sensing, technology is used to record an object's natural radiation. An infrared camera on a tripod that records heat coming from a rock formation, or an airplane flying over a rain forest that registers the sunlight reflected from the forest's canopy are examples of passive remote sensing.
Active remote sensing takes place when a device sends out a signal in order to gather information about an object. A ship that sends sonar waves to scan the ocean floor uses active remote sensing as do satellites that monitors hurricanes.
Although you may not realize it, you benefit from the results of remote sensing almost everyday. Meteorologists count-on it's a help generate weather forecast, police use it to catch speeding cars, and geologists use it to create maps of all kinds.
A special type of remote sensing called Light Detection and Ranging or LIDaR is a type of active remote sensing that uses lasers. LIDaR is used by everyone from farmers to help fertilize their crops to engineers who use it to help them survey the land. In fact, you're using a type of passive remote sensing right now. Human eyes and ears capture light and sound waves and allow us to detect information about an object without even touching it.