Philosophy, methods and techniques: from cartography to geo-informatics

Detail

Two parts shared by every branch of geography

• Every branch of geography has two parts in common. This is true for physical, human, systematic and regional geography alike.
• Philosophy is the "why" and "how we think" part.

• Methods and techniques are the "how we collect, show and study data" part.

• So a geomorphologist (someone who studies landforms) and an urban geographer (someone who studies cities) study different things. Both still use the same thinking traditions and the same toolkit.

Common part	What it covers	Simple meaning
Philosophy	(a) Geographical thought; (b) land and human interaction, also called human ecology	How geographers have thought about the Earth over time, and how people and their surroundings shape each other
Methods and techniques	Cartography (including computer cartography); quantitative or statistical techniques; field survey methods; geo-informatics (remote sensing, GIS, GPS)	The tools used to collect, measure, show and analyse spatial data

Philosophy: (a) geographical thought

• Geographical thought is the history of ideas in geography. It covers how scholars have defined the subject and studied it over time.
• Classical roots:
• The Greek scholar Eratosthenes (276–194 BC) first used the word "geography". It comes from Greek geo (earth) and graphos (description).

• Ptolemy and Varahamihira belong to this same early tradition of describing and mapping the known world.

• 19th century: Alexander von Humboldt and Carl Ritter gave geography its two main approaches.

• Systematic approach: you study one feature, such as climate, across the whole world.

• Regional approach: you study all the features of one region together.

• Why it matters: this thinking decides what questions geographers ask. The methods then decide how they answer them.

Philosophy: (b) land and human interaction (human ecology)

• Human ecology is the study of how people and their natural surroundings (land, climate, water, soil, plants) act on each other.
• Nature shapes people. For example, landforms, rain and soil decide where farming and settlements are possible.
• People reshape nature. They do this through farming, mining, building cities and changing river flows.

• The result is a cultural landscape. This is a landscape that carries the marks of human activity.

• This two-way link is at the heart of geography. It is what makes geography a bridge between the natural sciences and the social sciences.

Methods and techniques: the four tools

• Cartography (map-making):
• Cartography is the science and art of drawing maps.

• It has moved from manual cartography (maps drawn by hand) to computer cartography (maps drawn and updated with software).

• Quantitative or statistical techniques:

• These use numbers and statistics, such as averages, percentages and correlation, to measure and compare places.

• Examples include rainfall averages, population density and crop yield.

• Field survey methods:

• Here data is collected directly on the ground. This is done by observing, measuring, taking a sample of people or places, asking questions in a questionnaire, and interviewing.

• Geo-informatics:

• Geo-informatics means using computer and space technology to collect, store, analyse and show data about places on Earth.
• Remote sensing collects information about the Earth's surface from a distance, usually with sensors on satellites or aircraft. Nothing touches the ground.
• GIS (Geographic Information System) is computer software that stores different map data as separate layers, such as roads, rivers, soils and population. It lays them one over another and analyses them together.
• GPS (Global Positioning System) is a satellite system, run by the USA, that gives the exact location (latitude, longitude, height) of a receiver anywhere on Earth.

The toolkit keeps changing

• The list of methods is not fixed. It grows as technology changes.
• Manual cartography became computer cartography. Maps can now be redrawn and updated quickly.
• Technology handles huge amounts of data. Computers can process census, satellite and climate data that would be impossible to handle by hand.
• The internet supplies information. Data, maps and satellite images can be shared instantly.
• GIS "opened vistas of knowledge". Layering many data sets reveals patterns that a single map cannot show.

• GPS finds exact locations. It is used in surveying, navigation and disaster response.

• The NCERT link to national development: skills in GIS and computer cartography let students contribute to national development, for example in planning, resource mapping and disaster management.

Update: from GPS to GNSS and NavIC

• GNSS (Global Navigation Satellite System) is the general name for all satellite navigation systems. GPS (USA) is one member of this family. (NCERT uses only the term "GPS".)
• NavIC (Navigation with Indian Constellation), earlier called IRNSS, is India's regional navigation satellite system. A regional system covers India and the area around it, not the whole globe.
• Second-generation NVS satellites:
• NVS-01 was launched on GSLV-F12 on 29 May 2023. It is the first second-generation satellite. It carried an indigenous (India-made) atomic clock for the first time. It is operational [6][5].
• NVS-02 was placed in an elliptical transfer orbit (170 × 37,785 km, 20.8° inclination) on 29 January 2025. Its orbit could not be raised to the final circular orbit, so it is not operational [5][7].

• Cause of the NVS-02 failure: the drive signal did not reach the pyro valve of the oxidiser line of the engine meant for raising the orbit (finding of ISRO's Apex Committee) [7].

• Current status (Parliament reply, 2026):

• IRNSS-1F has finished its 10-year mission life.
• Only three satellites now give PNT (Position, Navigation and Timing) services: IRNSS-1B, IRNSS-1I and NVS-01 [8].
• At least four working satellites are needed for basic positioning. So NavIC cannot give standalone positioning service right now. Its timing service still works [8].

India's geospatial context

• Geospatial data is data tied to a location on Earth, such as maps, satellite images and survey points.
• Geospatial Data Guidelines (15 February 2021):
• Indian entities no longer need prior approval, security clearance or a licence to collect and produce geospatial data and maps [2].
• Geospatial data made with public funds is now open to all Indian entities for scientific, economic and development use. Classified data held by security and law-enforcement agencies is the exception [2].
• High-accuracy data is reserved for Indian entities. This means data finer than 1 m horizontal and 3 m vertical accuracy. Only Indian entities may collect and own it, and it must be stored on servers located in India [2].

• The old clearance system was replaced by self-certification, where users declare that they follow the rules [3].

• National Geospatial Policy (NGP) 2022:

• It came after the 2021 guidelines and brought the governance rules together. The Department of Science and Technology (DST) leads it [3].

• It promotes geospatial technology parks, incubation centres and industry accelerators [3].

• Infrastructure linked to NGP (DST, February 2024):

• Survey of India set up a pan-India CORS (Continuously Operating Reference Stations) network. These are fixed GNSS stations that make positioning accurate to a few centimetres [3].

• More than 2.8 lakh villages were mapped by drone under the SVAMITVA scheme (rural property mapping) [3].

• Survey of India:

• Founded in 1767, it is India's National Mapping Agency.

• It is one of the oldest scientific departments of the Government of India and has done survey and mapping for over 250 years [4].

• Bhuvan:

• Bhuvan is ISRO's geoportal (a website for viewing and downloading map data). It is hosted by NRSC (National Remote Sensing Centre), Hyderabad.
• It offers IRS (Indian Remote Sensing) satellite imagery, maps, terrain data, and vector layers such as administrative boundaries, soils and census data [9].

Organisation or system	Parent body	Role
Survey of India (1767)	DST	National Mapping Agency; topographic maps; CORS network
NRSC – Bhuvan	ISRO (Department of Space)	Satellite remote-sensing data and geoportal
NavIC (IRNSS / NVS)	ISRO	Regional satellite navigation (part of the GNSS family)
Geospatial Data Guidelines 2021 and NGP 2022	DST	Opened up geospatial data for Indian entities

Prelims Hooks

• The two parts common to every branch of geography are philosophy and methods and techniques.
• Human ecology is another name for land and human interaction, which is part of geography's philosophy.
• Geo-informatics includes remote sensing, GIS and GPS. Cartography and field surveys are separate methods, not part of geo-informatics.
• In NCERT's words, GIS "opened vistas of knowledge" and GPS finds exact locations.
• Survey of India was founded in 1767 and is the National Mapping Agency. Bhuvan belongs to ISRO's NRSC, not Survey of India.
• The Geospatial Data Guidelines came out on 15 February 2021. Data finer than 1 m horizontal / 3 m vertical accuracy is reserved for Indian entities and must be stored in India.
• NVS-01 (29 May 2023, GSLV-F12) carried India's first indigenous atomic clock. NVS-02 (29 January 2025) failed to reach its final orbit.
• NavIC is a regional system and GPS is a global one. Both belong to GNSS. NavIC needs at least 4 working satellites for positioning and had only 3 in 2026.

Mains Points

• Changing tools have widened what geography can do.
• The subject moved from manual maps to computer cartography, GIS and remote sensing.
• This turned geography from a descriptive subject into an analytical one that can handle data.

• It is now used in land-use planning, watershed management, disaster mapping and the census (GS-I).

• Open geospatial data supports development.

• The 2021 guidelines and NGP 2022 replaced approvals with self-certification.

• Together with the CORS network and SVAMITVA drone mapping, this supports property rights, local planning and private geospatial firms (GS-III: infrastructure, science and technology).

• Strategic self-reliance in navigation.

• NavIC lowers India's dependence on GPS for defence and civilian timing and positioning.

• The NVS-02 failure and the fall to three working satellites show how fragile the constellation is. Timely replacement launches are needed (GS-III).

• A skilled workforce matters. Training in GIS and computer cartography turns geography graduates into contributors to national development, as NCERT notes.