OCD audiophiles rejoice. “A statistical description of ground-to-ground sound propagation” by Schomer shows much your listening experience changes day to day. This longterm study breaks down the huge variations that occur in outdoor listening situations. Schomer played a series of independent frequency tones over and over again. These tones were over a series of months. The sounds were recorded at various distances. These parameters were kept constant. The atmosphere was always changing. The variations were much wider than anybody expected.
Check out his full abstract,