  The Zwicky Transient Facility is a time-domain optical survey that has
substantially increased our ability to observe and construct massive catalogs
of astronomical objects by use of its 47 square degree camera that can observe
in multiple filters. However the telescope's i-band filter suffers from
significant atmospheric fringes that reduce photometric precision, especially
for faint sources and in multi-epoch co-additions. Here we present a method for
constructing models of these atmospheric fringes using Principal Component
Analysis that can be used to identify and remove these image artifacts from
science images. In addition, we present the Uniform Background Indicator as a
quantitative measurement of correlated background noise and its relationship to
reduced photometric error after removing fringes. We conclude by evaluating the
effect of our method on measuring faint sources through the injection and
recovery of artificial faint sources in both single-image epochs and
co-additions. Our method for constructing atmospheric fringe models, and using
those models for cleaning images, is available for public download in the open
source python package fringez.
