A method of estimating lung motion includes collecting multiple ultrasound image data captured at one or more locations of a sample region of tissue. The method further includes comparing the multiple ultrasound image data and determining temporal correlation coefficients between each of the multiple ultrasound image data. The method still further includes displaying an image of the sample region of the tissue with the temporal correlation coefficients identified, thereby indicating lung motion. In further methods, the determined temporal correlation coefficients are used to determine an amount of decorrelation, which can be used to determine strain of the tissue over the sample region and to calculate lung displacements and lung shape changes representing ventilation.