State the merites and demerites of satallite imageries
Answers
But satellite imagery is more than just a curiosity. It’s easier than ever to use this technology for many applications from construction to natural disaster recovery. Many industries, including federal, state and local agencies, and natural resources, architecture, engineering and construction companies, use satellite imagery as an essential part of their jobs.
When the U.S. government launched the first satellite in 1958, the country was in the midst of the Cold War. In the 1990s, satellite imagery became commercially available, and an industry was born. Today, everyday users can obtain satellite data from commercial suppliers to help add depth of understanding to their projects.
So why would you use satellite imagery? First, it can help create a more accurate base map, which is a map on which primary data and interpretations can be plotted such as roads, rivers, and city
These are the merits of satellite imagety
Disadvantage of satellite imagery.
Remote sensing is a fairly expensive method of analysis especially when measuring or analyzing smaller areas.
Remote sensing requires a special kind of training to analyze the images. It is therefore expensive in the long run to use remote sensing technology since extra training must be accorded to the users of the technology.
It is expensive to analyze repetitive photographs if there is need to analyze different aspects of the photography features.
It is humans who select what sensor needs to be used to collect the data, specify the resolution of the data and calibration of the sensor, select the platform that will carry the sensor and determine when the data will be collected. Because of this, it is easier to introduce human error in this kind of analysis.
Powerful active remote sensing systems such as radars that emit their own electromagnetic radiation can be intrusive and affect the phenomenon being investigated.
The instruments used in remote sensing may sometimes be un-calibrated which may lead to un-calibrated remote sensing data.
Sometimes different phenomena being analyzed may look the same during measurement which may lead to classification error.
The image being analyzed may sometimes be interfered by other phenomena that are not being measured and this should also be accounted for during analysis.
Remote sensing technology is sometimes oversold to the point where it feels like it is a panacea that will provide all the solution and information for conducting physical, biological or scientific research.
The information provided by remote sensing data may not be complete and may be temporary.
Sometimes large scale engineering maps cannot be prepared from satellite data which makes remote sensing data collection incomplete.