Abstract
Rakov and Uman pointed out (Lightning: Physics and Effects, 2003) that
despite 5000 published reports of ball lightning (BL) and a scientific
literature comparable in volume to the literature on conventional
lightning, we still have no idea of what mechanisms create or power BL.
Lightning characterization technology advances can and should be applied
to BL studies. Keul and Diendorfer (2018) have correlated BL reports
with European lightning-detection network data, but no such attempt has
been made for US BL reports up to now. Using 31 BL reports from a
now-defunct US website, we have attempted correlations with National
Lightning Detection Network (NLDN) and radar data archived at the
National Climactic Data Center. Of the 31 reports, 5 objects were
indoors and 25 were reported to coincide with thunderstorms. Time
information accurate to 30 minutes (1 sigma) and location information
accurate within one to ten km was available from nine of the reports,
and for these we obtained both NLDN and composite radar data covering
the time frames indicated by the reports. For three of the nine reports,
we found NLDN located strikes plausibly within the distance and time
frames of the observer reports – thus qualifying as nearby (possibly
causal) lightning. However, for the report for which the location of the
ball was known within meters, the nearest lightning was 2.3 km away. 23
reports only associate BL with a storm within 25 km. Should it continue
to hold in the face of more evidence, the relative lack of correlation
of BL and nearby lightning suggests that the production of BL is
associated more with static or changing electric fields in the vicinity
of thunderstorms, than with the lightning plasma channel itself. While
these results by themselves are limited, we are optimistic that one can
learn more about the link between natural and ball lightning by fusing
more precise eyewitness reports with lightning location and other
archival meteorological data. To this end, we have launched a website to
guide citizen scientists in future ball lightning reports. The site may
be reached via https://tinyurl.com/BLReport.