Coal-fired power plants in Ohio emit sulfur dioxide (SO2) continuously into the atmosphere. The pollution plume is advected to the northeast with a constant speed 5 m/s. We assume no dilution of the plume during transport, i.e., that an advecting air parcel is closed in a thermodynamic sense (no mass input and no mass output). Let Ao be the concentration of SO2 at the point of emission; SO2 in the plume has a lifetime of two days against oxidation to sulfuric acid (H2SO4), and H2SO4 has a lifetime of 5 days against wet deposition. We view both of these sinks as first-order processes ( 1k =0.5 day-1, 2 k =0.2 day-1).

Assume no dilution and plot [SO₂] and [H₂SO₄] as functions of distance (x) downwind of the plant cluster.