With advances in remote-sensing technology and higher-quality products, the field of spectral indices has experienced a sizeable progressive evolution. These spectral indices computed by using different brands of remote-sensing products and applying additive, subtractive, or normalizing operations, have been and are being devised to detect diverse objects in various spheres of our planet. For instance, there are spectral indices that detect and delineate plant leaf moisture, that biome comes under biosphere, at distinctive spatial scales. There are other indices that are used to extract elements from the lithosphere like iron oxide content, or to show clay mineral content, etc. Similarly, there are spectral indices to detect various elements which constitute other spheres of our planet. In this work, we have used the Web of Science (WoS) database from 1999 to 2022 and searched for only English language research journals, book chapters, books, and scientific reports. We found 2227 documents in all the categories to perform a systematic, scientometric review regarding spectral indices used for the identification of elements constituting various objects of the five different spheres. The primary objective of this chapter is to present a systematic and scientometric review of spectral indices used for quantification of different elements of all the spheres of our planet relating to lithosphere, hydrosphere, atmosphere, biosphere, and anthroposphere, across remote-sensing platforms and sensors. The study also examines the rationale of spectral indices across the ever-advancing remote-sensing platform and sensors, and their future challenges, and investigates the challenges and prospects of this domain of study. This study will be useful for acquainting new researchers with the use spectral indices for their specific objectives.

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Advances in Remote Sensing Technology and the Three Poles, First Edition. Edited by Manish Pandey, Prem C. Pandey, Yogesh Ray,
Aman Arora, Shridhar D. Jawak, and Uma K. Shukla.
© 2023 John Wiley & Sons Ltd. Published 2023 by John Wiley & Sons Ltd.
6
Spectral Indices Across Remote Sensing Platforms and Sensors Relating
to the Three Poles
An Overview of Applications, Challenges, and Future Prospects
Mallikarjun Mishra1
, Kiran Kumari Singh2,13
, Prem C. Pandey3
, Rahul Devrani4
,Avinash Kumar Pandey5
,
KN Prudhvi Raju1
, Prabhat Ranjan6
,Aman Arora7
, Romulus Costache8
, Saeid Janizadeh9
,
Nguyen Thuy Linh10
, and Manish Pandey11,12,
*
1
Department of Geography, Ravenshaw University, Cuttack, Odisha, India
2
Department of Geography, Central University of Punjab, Bathinda, Punjab, India
3
School of Natural Sciences, Shiv Nadar Institution of Eminence, Greater Noida, Uttar Pradesh, 201314, India
4
Delhi School of Climate Change & Sustainability, Institution of Eminence, University of Delhi, Delhi - 110007, India
5
Department of Chemistry, GLA University, Chaumuhan, Mathura, Uttar Pradesh, India
6
Central Pollution Control Board, Ministry of Environment, Forest, and Climate Change, Parivesh Bhawan, East Arjun Nagar, Shahdara, Delhi, India
7
Bihar Mausam Seva Kendra, Planning and Development Department, Government of Bihar, Patna, Bihar, India
8
Department of Civil Engineering, Transilvania University of Brasov, Brasov, Romania
9
Department of Watershed Management Engineering and Sciences, Faculty in Natural Resources and Marine Science, Tarbiat Modares University, Tehran, Iran
10
Institute of Applied Technology, Thu Dau Mot University, Binh Duong province, Vietnam
11
University Center for Research & Development (UCRD), Chandigarh University, Mohali, Punjab, India
12
Department of Civil Engineering, University Institute of Engineering, Chandigarh University, Mohali, Punjab, India
13
Department of Geography, Central University of South Bihar, Gaya-824236, Bihar, India
* Corresponding author
spectral bands are employed, keeping in view the spectral
response to the ground features.
Remote sensing helps to acquire spatial and temporal
data and to increase our understanding of polar dynamics.
It is a system that measures electromagnetic energy ema-
nating from an object. However, the remotely-sensed
images are the result of various interrelated processes and
can provide information about the characteristics of the
surface materials based on characteristics of electromag-
netic radiation, atmospheric interaction, and sensor char-
acteristics (Campbell and Wynne, 2011). Remote-sensing
technology has advanced tremendously over the past few
decades in terms of its spectral (ranging from visible to
microwave), spatial (ranging from kilometer to sub-
meter), radiometric, and temporal (from years to months
to hours to minutes) characteristics, which have facili-
tated the research community to experiment with varie-
ties of remotely-sensed data (Liang and Wang, 2020).
Fortunately, various satellite platforms have made multi-
spectral data freely available to research community, such
as the Landsat series (30 m spatial resolution) and Sentinel
2 (10 m and 20 m spatial resolution of different spectral
bands). The commercially available data are available at a
very fine spatial and higher spectral resolution. In recent
times, the use of UAVs (Unmanned Aerial Vehicles) and
LiDAR have surged forward to acquire spatial information
with higher spatial and temporal resolution.
6.1 Introduction
In recent years, remote-sensing technology has advanced
our knowledge in polar research. Satellite-based observa-
tions such as optical (Landsat series), synthetic aperture
radar (SAR) satellite imagery, and very-high-resolution
images have been applied through various analytical tech-
niques to understand the dynamic processes operating in
the lithosphere (Özkan et al., 2018), atmosphere (Yang et
al., 2020), biosphere (Yang et al., 2020), hydrosphere
(Cermakova, et al., 2019), in general, the cryospheric com-
ponent of the hydrosphere (How et al., 2021), and anthro-
posphere (DaCamara et al., 2019; Agyeman et al., 2021).
Figure 6.1 illustrates the spheres of our planet, and various
objects, also called “Elements of Identification (IoE),” that
advances in remote-sensing technology has helped, is help-
ing, and will help plan future missions by space agencies of
different countries and groups of countries aiming to mon-
itor and manage the betterment of our society. Remote
sensing has been widely used to understand geology, geo-
morphology, ice shelfs, glaciers, coastlines, and vegetation
cover. The study of the polar regions is of utmost impor-
tance to understand the atmospheric–oceanic process of
the globe. This review paper has compiled a comprehen-
sive database on remote-sensing application of polar
research through various spectral indices. Several impor-
tant challenges are discussed that occur when different