This insane rationalization is hilarious! They’ll go to any length to find a human marker in random weather cycles.
Perhaps that 8 feet they reference was not the norm. From another study regarding the Sierra Nevada climate of 1650-1850 they state:
Climate varies not only spatially but also temporally, with
some periods being relatively wet and others relatively dry,
some relatively cool and others warm. Putting aside for now
the year-to-year and decade-to-decade variations in climate,
it is possible to characterize the period from the mid-1600s to
the mid-1800s as having been, by modern standards, abnormally
cool and moderately dry. This interval was preceded
by several centuries of cool and wet conditions and was followed
by the relatively warm and wet conditions of the past
145 years. Evidence for these generalizations comes from several
sources.