Increasing trends of wet deposition of RNS such as NO3- and NH4+ have been reported in South Asia, particularly over Himalayas and Indo-Gangetic region due to long range transport as well as local emission sources. Wet deposition fluxes of RNS reported at Gulmarg are increased almost two folds in 2012–13 compared to 1986–87. Prevalence of secondary aerosols like ammonium sulfate and ammonium nitrate is also noticed. Most sites in South Asia show very high Ammonium Availability Index (AAI) values highlighting presence of sufficient NH₄⁺ to efficiently neutralize the acidity created by NO₃⁻ and SO₄²⁻. However, some sites show lower AAI values, suggesting comparatively limited neutralization capacity.