Wednesday, March 28, 2012
1638 - 44 Volcano Cluster
Sometimes one gets lucky. I am reading an odd item written by Tonio Andrade on the short history of the Dutch Colony, or more correctly the Dutch trading base established on Taiwan during the early seventeenth century that was over run by a Chinese warlord in early 1662. The Dutch had made an impressive start on establishing control on the island including the subduing of tribals and bringing in Chinese growers.
However what tipped the scales was the onset of the Little Ice Age during the mid 1640's. As I posted a couple of years back, I need a causation for the sharp decline in global temperatures for this particular event. Volcanism was the easy option except it was not particularly in evidence. In fact this source informs us that twelve major eruptions took place between 1638 and 1644, or around two per year, all sufficient to cause a lowering of the global temperature and together ample to produce the two degree drop actually experienced.
Without significant volcanism, the global temperature will trend toward the highs we are currently experiencing. Solar variation may or may not significantly contribute but its contribution is close to a half degree at best and although significant, it is not comparable to a two degree shift as was effectively experienced, although some will want to argue the actual size. A major volcano is able to reduce temperatures by a full degree for around perhaps half a year with a long tail afterward as the disturbance is fully corrected. Thus twelve such events will over six years will surely be sufficient to reduce global temperatures for the duration and to linger in its effects for decades as the now colder Arctic regions slowly warm up.
With a cooler climate regime established, later volcanic events will be more effective at recooling the climate, so recovery will be slowed naturally. That is certainly what was experienced.
Most importantly, we now can emphatically state that the global cooling events experienced over the past few millennia are most certainly derived from clusters of volcanic events. The
has also been grossly underestimated in its ability to deflate global
The potential of a cluster of volcanoes been triggered along the so called ring of fire has always been theoretically apparent and we presently are riding through a period of coastal tsunamis that are also evidence of a general connectedness in tectonic events along the ring of fire. So far it is coincidental, and it appears to have generally settled down but the fact remains that one large release can set in motion other systems. The ring is what connects Sumatra, New Zealand and Japan.
How a cascade of Volcanoes could occur is much more challenging as connectivity is not apparent except resulting from ring itself. There may be another form of tectonic activity that has not been observed which uniformly stresses the volcanoes themselves allowing eruptions to occur in close temporal proximity to each other. The take home warning is that it is possible and that it likely happens every thousand years or so.