An Assessment of Magnetic Conditions for Strong Coronal Heating in Solar Active Regions by Comparing Observed Loops with Computed Potential Field Lines

We report further results on the magnetic origins of coronal heating found from combining coronal images with photospheric magnetograms. Here, for two complementary active regions, we compare the measured photospheric magnetic roots, extrapolated potential fields, and the distribution of bright coronal loops, to examine the global nonpotentiality of bright extended coronal loops and the three-dimensional structure of the magnetic field at their feet and to assess the role of these magnetic conditions in the strong coronal heating in these loops.