Humans are typically within fifty meters from the urban sources. We developed a new dispersion model that can be used to estimate the impact of urban sources at source-receptor distances of tens of meters.

An experiment was conducted at the Dugway Proving Ground, Utah, to simulate a source in an urban area modeled at a scale of roughly 1:10
　

Horizontal and vertical plume spreads observed in an array of obstacles are enhanced over those in flat terrain

Model performance is better when we introduce an initial plume height to account for the enhanced dispersion associated with array of obstacles