Latitudinal distribution of radon-222 flux from continents

Global atmospheric transport models are frequently tested by using 222Rn as a tracer. Generally this tracer is assumed to be emitted at a uniform rate (1 atom cm−2 s−1) from all ice-free land surfaces. The analysis of published data suggests a strong decrease from 30°N northwards to 0.2 atom cm−2 s−1 at 70°N. This could be a result of increasing water tables and proportions of organic soils as indicated by larger proportions of wetlands in northern latitudes