1. A method for jointly estimating an image degradation and reconstructing an image of a subject using a magnetic resonance imaging (MRI) system, the steps of the method comprising: a) acquiring a k-space data set using the MRI system; b) repeating step a) to acquire multiple k-space data sets while using a different acquisition parameter during each repetition of step a) such that each of the multiple k-space data sets is acquired using a different acquisition parameter; c) jointly estimating the image degradation and reconstructing an image of the subject in which the image degradation is mitigated by iteratively performing the steps of: i) estimating the image degradation from the multiple k-space data sets acquired in steps a) and b); and ii) reconstructing the image of the subject in which the image degradation is mitigated using the image degradation estimated in step c)i) and the multiple k-space data sets acquired in steps a) and b).