What is Remote Sensing?
Remote sensing (RS) is the acquisition of information about an object or phenomenon without making physical contact with the object. It involves the use of sensors to record the Electromagnetic Radiation reflected or emitted from the object itself. Further, the information collected through RS can be used to create a digital map, assess environmental conditions, manage resources and secure public safety. There is different types of data which is generated by using Remote Sensing and GIS i.e. Vector and Raster Data.
How Remote Sensing is used in Geography?
Remote sensing has become an invaluable tool in geography, providing researchers with means to study our planet and any changes from afar. There are a variety of different RS techniques, but all share the ability to collect information about an object or area without any physical contact. This ability to collect data from a distance has made RS an important tool in studying geography, especially when it comes to studying our changing planet. We use RS techniques to collect data about different aspects of geography. These aspects include land features, vegetation, weather, and even the movement of people and animals etc. Moreover, one can use this data to create maps and models of the earth’s surface, and to study changes over time. For example, climatologists can track the growth of forests, monitor the movement of glaciers, and track the spread of wildfires through RS.
Advantages of Using Remote Sensing in Geography
There are many advantages to using remote sensing in geography. Some of these
- Remote sensing (RS) can provide a more complete and accurate picture of the Earth’s surface than traditional methods such as land surveying. This is because remote sensing can collect data from a much larger area than is possible with manual methods.
- We can use RS data to detect and map features that are not visible from the ground. For example, scholars map the distribution of vegetation, land use, and land cover.
- The scientists can construct three-dimensional models of the Earth’s surface by using RS data.
- It can be used to monitor changes in the Earth’s surface over time. It is possible to track the effects of climate change, deforestation, and other environmental changes through the use of RS & GIS.
Disadvantages of Using Remote Sensing in Geography
There are many advantages of RS, however, there are also several constraints or disadvantages to using RS in geography.
- The resolution of the imagery is not always high enough to identify features of interest.
- The cost of acquiring and analyzing satellite imagery can be prohibitive for many researchers.
- Cloud cover can often obscure satellite imagery, making it difficult to obtain a clear picture of the Earth’s surface.
- The interpretation of satellite imagery can be subjective, and different researchers may interpret the data in different ways.
- The availability of satellite imagery can be sporadic, and it may not be possible to obtain the imagery that you need when you need it.
- Governments restrict the access to a lot of RS data for national security reasons.
Remote sensing has become an important tool in geography, especially in the study of landforms and their changes over time. It allows us to see features that are not easily visible from the ground, and to track changes in these features over time. This can help us to understand how the landscape changes through natural and human processes. Scholars use it to study a wide range of features including:
- Landforms such as mountains, valleys and plains.
- Vegetation, including forests, grasslands and crops.
- Rivers and lakes.
- Human settlements and infrastructure.
- The changing climate.
Dr. Nisha is an Assistant Professor of Geography at Kamala Nehru College, University of Delhi.