Interpreting the CHARM Page: For a detailed description of CHARM
algorigthm, please see the methods paper: Krista and Gallagher
(2009) The EIT 195 Å disk images are shown as cylindrical
Lambert equal-area projection maps. The projection is limited to
80 degrees due to limb-extrapolation effects. The white corners
shift over the year due to the change in the B angle, for which
the projection is corrected for. After the detection of low
intensity regions in the EIT 195 Å images, corresponding MDI
magnetograms are used to determine the flux imbalance in the
detected regions. Depending on the flux-imbalance, low intensity
regions are classed as coronal holes (CH). This is based on the
knowledge that CHs are dominated by a single polartity. Please
note that the error in the MDI magnetic field measurements
increases considerable towards the solar limb and hence the flux
imbalance might not be detected in certain polar CHs. For this
reason polar holes are occasionally unidentified in the
observations. We are current