Advances in Remote Sensing Technology and the Three Poles

3 Assessing the Accuracy of Digital Elevation Models for Darjeeling-Sikkim Himalayas

Prodip Mandal¹ and Shraban Sarkar^1,*

¹ Department of Geography, Cooch Behar Panchanan Barma University, Cooch Behar, West Bengal 736101, India^* Corresponding author

3.1 Introduction

Digital Elevation Model (DEM) presents the elevation of the Earth’s surface in digital form by an array of grids or lists of three-dimensional (3D) coordinates. DEM is also known as the Digital Height Model (DHM), Digital Ground Model (DGM), Digital Surface Model (DSM), and Digital Terrain Model (DTM). These terms originate from different countries (Li et al., 2004). More specifically, DSM represents the Earth’s surface elevation including all objects (i.e., vegetation and man-made features), while DTM contains elevation of the bare Earth’s surface (Martha et al., 2010). DEM is often used as a generic term for DSM and DTM (Hirt, 2014), only representing height information without defining surface characteristics (Peckham and Jordan, 2007).

In recent years, DEM has become an essential data in various research fields, including geomorphology (Boulton and Stokes, 2018), oceanography (Libina and Nikiforov, 2020), climatology (Daly et al., 2002, 2008), and biodiversity (Sesnie et al., 2008). The various topographic and hydrologic parameters such as slope, aspect, curvature, drainage networks, Topographic Wetness Index (TWI), Stream Power Index (SPI), etc. can be extracted from DEM. These parameters are a prerequisite ...