The receptor for material which is removed from the atmosphere. Because of long range transport of many pollutants such as
SO2, sulfuric acid and its salts, the sink region can be many hundreds of kilometres from the source region of the pollutants.
Source:
PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2213 (https://doi.org/10.1351/pac199062112167)