| Near 536 A.D., famine, frost, and darkness were
recorded both in the Irish and Chinese historical documents. The
purpose of this ar-ticle is to identify a possible cause of the dust
veil: a cometary or meteoritic impact. The hypothesis of the 536 A.D.
atmospheric changes can be examined through dendro-chronology,
Greenland ice cores, and history. Firstly, dendrochronology is the
study of the growth of tree rings. It is useful because by measuring
the growth rate we can deduce the atmospheric environment of a certain
period in time. We will concentrate on the tree rings of the Irish oak
because of the historical evi-dences. The dendrochronology of the Irish
oak shows that the narrowest rings were in 540 A.D. to 542 A.D. The
stunted growth probably was caused by poor temperature and environment.
Secondly, we will examine the Greenland Dve-3 core to determine whether
the poor growth was triggered by volcanic activities. The ice core
shows that the acid layer of the volcanic activity. The acid layer from
the volcanoes in the Greenland core moved from 540 A.D. ± 10 to 516
A.D. ± 4 indicates that the hypothesis of volcanic ac-tivities on Earth
that brought about the famine in 536 A.D. was not substantiated.
Thirdly, the Irish history recorede that the “dust veil” and “running
stars” were shining for 20 days, and there were many earthquakes. Both
in China and Byzantium in 530 A.D., Halley’s Comet was recorded that
the comet continued to shine for 20 days. In both China and Europe,
black clouds, earthquakes, crop fail-ures, frost, and dust veil were
recorded. In China, the dragons fought in the ponds and the trees were
broken when “a dragon” passed by. Although the Chinese thought that the
comet was connected with the fall of the dy-nasty, the power struggles
between the states within China would rather be the main cause for the
poor political conditions, economical conditions, and livelihood. Also
the poor at-mospheric environment compounded the problem. Overall, the
comet or bolide is a possible cause from the recorded documents. The
most plausible hypothesis, up until now, is that a comet or a meteorite
hit the Earth. It is because the hypothesis of volcanic dust veil
contradicted with the evidence of the acid layer in the ice core.
However, if a bolide struck the Earth, it would have brought about the
reduced sunlight, atmospheric changed, failure of crops, plagues, and
earthquakes. It might be the cause of the atmospheric changes. It might
have been a water impact or an impact crater that has not yet been
identi-fied. If a bolide hit the Earth at this point and caused global
effects the current threat might be more than expected. The explosion
of Thera, a terrestrial event caused the downfall of several
civilizations as would a meteorite impact of the extent hypothesized
above to have occurred during the early Middle Ages. It might give some
indication as to the global impacts on society and the environment of
what might have been the hit that pushed Europe into a social descent
that it did not recover from until well into the Middle Ages. |