The datum debate continues
Dr Kumar says solutions are available, Do you agree?
Indian geodesists have the know-how and expertise to carry out these tasks. Of course, all help from expert agencies like National Geodetic Survey, USA; DMA, USA, and expert persons like Dr Muneendra Kumar is welcome and should be taken. Unfortunately, many of our Government departments like SoI do not make use of the expertise available outside their own Department, like experts in other scientifi c and academic organisations and Institutes, retired Geodesists, etc. Their contribution and advice would be of great help in putting these highly scientifi c tasks on the right track and in expediting them. Probably an eminent and young, dynamic Geodesist as Head of SoI would be able to provide the leadership and guidance required for these important national tasks!
Not advisable to stick to weak datum: LT GEN SURINDAR P MEHTA
Questions have been raised at various quarters whether the Vision invoked
Before I comment on this, let us review briefl y the broad classifi cation
• Cartography for Macro level planning and execution. Requires depiction of all major topographical details (both physical and manmade) relatively correct to enable macro level study and planning of land related activities. Topographical maps on scale 1:25000 to 1:250000 have been used. Relative accuracy is important and distance, area and volume can be computed within limited accuracy, generally acceptable for macro level planning. Any suitable cartographic projection with any reasonable datum can serve the purpose.
• Cartography for Micro level planning and execution. This requires all terrain data accurate in size and shape in relative correct position so as to get true distance, area and volumes for micro level planning and execution of land related projects. These are large scale maps of the small area of interest. Some of the Engineering projects ( such as Irrigation) , require study on map scale 1:5000 to 1:10000 and further detailed planning, design and execution on larger scale (1:1000 or even larger). Relative accuracy of positioning of details is the prime requirement and absolute positioning and well defined datum is not mendatory.