Source Reconstruction in Low Wind Conditions from Atmospheric Concentration Measurements: A Renormalization Data Assimilation Approach

An inversion technique is proposed to reconstruct an elevated point emission source of unknown height of atmospheric trace species from a finite number of concentration measurements. This includes estimation of the height of release above the ground along with its projected release location on the ground and source strength. The inverse problem of identifying the parameters of a point source is addressed within the assimilative framework of renormalization approach. The proposed technique is illustrated with synthetic and real data from seven sets of observations taken from the low wind tracer diffusion experiment conducted at the Indian Institute of Technology Delhi (India) in 1991. With synthetic data, the methodology reproduces exactly the source location including height and its strength in all the runs validating the inversion technique. With real data, the average release height is estimated as 1.1 m in lieu of 1 m reported in the experiment. The release location is retrieved with an average Euclidean distance of 22 m from their true locations and the strength is retrieved within a factor of two from their experimental values in all the runs.