Fig. 4

Plot showing annual median (box plot of variabilities) δ13C at the NCAP sampling locations along with δ13C of sources from literature: (a) range of fossil fuel combustion from −22.6‰ to −27.2‰100, and (b) C3 biomass combustion from −24.2‰ to −30.1‰45,93. RTK: Rohtak; MYS: Mysuru; MOH: Mohali; BPL: Bhopal; BKN: Bikaner; JOR: Jorhat; KMR: Kashmir; SHY: Shyamnagar.