  We have investigated how the relative elemental abundances inferred from the
solar upper atmosphere are affected by uncertainties in the dielectronic
recombination (DR) rate coefficients used to analyze the spectra. We find that
the inferred relative abundances can be up to a factor of ~5 smaller or ~1.6
times larger than those inferred using the currently recommended DR rate
coefficients. We have also found a plausible set of variations to the DR rate
coefficients which improve the inferred (and expected) isothermal nature of
solar coronal observations at heights of >~ 50 arcsec off the solar limb. Our
results can be used to help prioritize the enormous amount of DR data needed
for modeling solar and stellar upper atmospheres. Based on the work here, our
list of needed rate coefficients for DR onto specific isoelectronic sequences
reads, in decreasing order of importance, as follows: O-like, C-like, Be-like,
N-like, B-like, F-like, Li-like, He-like, and Ne-like. It is our hope that this
work will help to motivate and prioritize future experimental and theoretical
studies of DR.
