Use of Cartosat-1 elevation data for local-scale terrain studies in India: a case study

ABSTRACT

The Cartosat-1 satellite provides relatively high-resolution elevation data, which is publicly available for free, for most parts of India. Yet, published works applying such data in the local geographical context are few. This paper illustrates the application of CartoDEM, an elevation dataset based on Cartosat-1, to develop a coarse geographic narrative of the terrain at the tehsil level. Kotra tehsil in Udaipur district of Rajasthan, India, was used as a case study. It was found that the data, along with the calibration and analysis methods used here, allows a fairly well-resolved understanding of the terrain of the tehsil, including identification of major landforms and quantification of terrain metrics such as elevation and roughness. The free and easy availability of such data shows offers the potential for such studies to be performed for any local area for which CartoDEM or similar data exists.

ABSTRAITE

Le satellite Cartosat-1 fournit des données d'altitude à assez haute résolution. Ces données sont accessibles gratuitement au public et couvrent la plupart des régions de l'Inde. Pourtant il y a peu de travaux publiés qui utilisent ces données dans un contexte géographique local. Cet article illustre l'utilisation de CartoDEM, des données d'élévation basées sur Cartosat-1, pour construire une représentation géographique synthétique du relief au niveau des unités administratives des tehsils. Le tehsil Kotra, situé dans le district d'Udaipur au Rajasthan en Inde, a été choisi comme cas d'étude. Il a été constaté que ces données, associées à des méthodes de calibration et d'analyse, permettent une compréhension assez fine du terrain du tehsil, dont l'identification des principales formes et la quantification des métriques du relief telles que l'élévation et la rugosité. La disponibilité gratuite et facile de ces données montre que des études similaires peuvent être réalisées pour toutes les régions pour lesquelles les données CartoDem ou équivalentes existent.

KEYWORDS:

• Terrain
• elevation
• roughness
• Cartosat-1
• cartoDEM

Acknowledgments

None

Data Availability Statement

The data that support the findings of this study are openly available from the following sources:

1. CartoDEM data: https://bhuvan.nrsc.gov.in/

2. Survey of India’s topographic maps: https://soinakshe.uk.gov.in/

3. Political boundaries: https://esri.maps.arcgis.com/home/item.html?id=f9c7dd3b816e4248b9b327e91b32d3d9

Disclosure statement

No potential conflict of interest was reported by the author(s).

Declaration of Interest Statement

No interest to declare

Notes

1 While the value of 30% is not an absolute threshold for steepness, it has been used in some slope classification systems, such as in FAO, 1993, as the threshold beyond which a slope can be classified as steep.

2 The name ‘Sabarmati (minor)’ is used to distinguish this river from the main stem of the Sabarmati River to which all rivers of the tehsil discharge.

Additional information

Notes on contributors

Rahul Ranade

Rahul Ranade is an amateur cartographer with a research interest in the Mewar region of India. This work arises out of ongoing research on the impact of terrain on the region's history.