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Tracking Development through

Satellite Images & Cartography CHAPTER

An important theme of this year’s Economic Survey is the use of new forms of data and information
for tracking economic activity and development. Chapter 1 looked at the use of high-frequency
data for the real-time management of an economy through uncertain times. This chapter looks at
the use of another kind of data – geo-spatial data and cartographic techniques – to track, compare
and represent longer term developments. Geospatial maps not only lets users visualize data but
also helps users to better understand trends, relationships and patterns. The use of maps is not
entirely new and previous Economic Surveys have used them for years, but there is now a plethora
of information from satellites, drones, mobile phones and other sources. Moreover, there has also
been a dramatic improvement in cartographic technology that allows for better representation of
the information. This chapter illustrates some of the interesting ways of depicting geospatial data.

Using satellite images, India’s night-time luminosity is compared between 2012 and 2021 in
Figures 1A and 1B. Night-time luminosity provides an interesting representation of the expansion
of electricity supply, the geographical distribution of population and economic activity, urban
expansion as well as growth of ribbon developments between urban hubs. Similarly, using
geospatial and cartographic techniques, the subsequent maps show the extent of physical as well
as financial infrastructure development in India. This includes expansion of national highways,
airports, commercial bank branches, metros, etc. The maps in Figure 5A & 5B depict change in
net sown area of India over the last 15 years. The maps have been created by combining satellite
data over the course of a 12 month period in each year.

The images in Figures 6A & 6B compare the Kharif crop cycle in Moga district, Punjab during
2005 and 2021. The images show that Kharif sowing cycle has shifted ahead by around two-to-three
weeks causing the Kharif harvest to almost coincide with Rabi sowing in November. The closing of
the gap is a likely factor that encourages farmers to burn stubble and may be related to restrictions
on early transplanting of Kharif paddy. These restrictions were introduced in 2009 in order to reduce
pumping of ground-water but may have had the unintended consequence of damaging air quality.

Satellite imagery is used to show annual water storage cycle at Stanley Reservoir, Tamil Nadu
in Figure 7A & 7B. Using new geo-spatial methods, population density of select Indian cities
is compared over time, showing the extent of urban expansion in Delhi-NCR and Bangalore
between 2001 and 2021. Finally, using satellite imagery, Figures 18A, 18B, 19A & 19B illustrate
wasteland redeployment in Andhra Pradesh and Gujarat.

While this chapter has restricted itself to static two-dimensional images due to practical considerations
of publication, readers will be aware that dynamic and multi-dimensional cartography is now
commonplace for every-day activities like ordering a taxi or looking for an address.