Blood Rain?
Back in September of 2020 I set up a Stratus Precision Rain Gauge (built to U.S Weather Bureau Standards) to begin recording daily
precipitation data to be contributed to the grassroot volunteer network
CoCoRaHS (Community Collaborative Rain, Hail, and Snow Network). Each day at 7 a.m., I record the amount of
precipitation, or lack thereof, into the organization’s app on my phone, which
is then used by a variety of organizations and individuals including the
National Weather Service. Anyway, I went
out this morning to check my gauge and found something unusual- the 0.02” of
rain that the gauge collected overnight had a reddish tint to it. I thought at first that maybe something had
fallen into the tube tainting the collected rain, but what? There was nothing other than water in the
tube. Then I remembered reading
something not long ago about “blood rain”.
Once believed to be a “bad omen” (especially in the Middle Ages and
earlier times), there is now a scientific consensus that it is a phenomenon sometimes
caused by aerial spores of the green microalgae Trentepohlia annulate or Haematococcus pluvialis that gets into clouds and in turn the rain giving it a red appearance. Also, it is believed to occur when dusts,
especially following dust storms, that contain iron oxides gets in the
mix. Even sunspots and aurorae have been
to blame.
This phenomenon is rare, but
it does occur occasionally.
Chances are my collected rain is not actually “blood rain” and
may have some other underlying cause for its coloration……but it is nice to
think it might be.
Labels: blood rain, citizen science, climate, meteorology, precipitation, stratus precision rain gauge, unusual weather, weather