Application of Integrated Remote Sensing, GIS and GNSS for Monitoring Desertification and Drought in Thar Desert, Rajasthan: A Systematic Review (2018-2026)

*Title: Application of Integrated Remote Sensing, GIS and GNSS for Monitoring Desertification and Drought in Thar Desert, Rajasthan: A Systematic Review (2018-2026) - Version 2 [Corrected Maps]* *Description:*This is Version 2 (Corrected) of the systematic review. This systematic review analyzes 68 research papers (2018-2026) and ISRO Bhuvan data to assess desertification and drought in Thar Desert districts of Rajasthan (Jaisalmer, Barmer, Bikaner, Jodhpur). The study uses NDVI, NDWI, Land Surface Temperature (LST) and GNSS/DGPS based ground truthing. Mean NDVI declined from 0.38 to 0.16 (-0.22) with 12,450 sq km under severe vegetation loss. *What is new in V2:*- Added 4 original maps prepared by author: Map 1 Location of Thar Desert (Corrected Political Map of India as per Survey of India, Govt. of India), Map 2 Formation, Map 3 Traditional Water System (Tanka), Map 4 Socio-economic Condition.- Corrected India map to show Jammu & Kashmir UT, Ladakh UT including Siachen Glacier, and Arunachal Pradesh as integral parts of India.- Corrected location of Thar Desert in North-West Rajasthan (Jaisalmer, Barmer, Bikaner, Jodhpur districts).- Added author footer and IIRS-ISRO certification. *Author:* Kishan Lal Jat, M.A. Geography, Vardhaman Mahaveer Open University, Kota. Scholar No. 261307-010037, Regional Centre Ajmer, Study Centre 1001 Dayanand College Ajmer. Village Bahadurpura, Bijay Nagar, Ajmer - 305624. IIRS-ISRO Certified in GIS & Remote Sensing, Indian Institute of Remote Sensing (IIRS), ISRO, Dehradun. *Keywords:* Thar Desert, Desertification, Drought, Remote Sensing, GIS, GNSS, NDVI, Rajasthan *Note:* Maps are prepared for academic/dissertation purpose based on Survey of India.