Panel a: PDF of the optical depths, log₁₀(τ), corresponding to the equipartition layer (v_A = c_s) associated with the locations of the blue dots and the area inside box A shown in Fig. 1f. Panel b: PDFs of the magnetic field inclination angles at photospheric (log₁₀(τ) = − 1.0, red and blue histograms) and chromospheric (log₁₀(τ) = − 4.6; dashed histograms) heights. Panels c and d: PDF distribution of the magnetic field gradient and density ratio for the selected region (i.e., the blue dots and box A).