Spud, Better evidence is that the little ice age was caused by solar variations esp the Maunder minimum. It lasted too long to be attributed to volcanos I would think. However volcanos and smaller asteroid impacts do certainly cause temporary temperature dips lasting for periods of a few years to perhaps a decade and these can initiate profound social changes. There is fairly good evidence that the dark ages were partially initiated by an eruption c. 535 AD. See http://en.wikipedia.org/wiki/Extreme_weather_events_of_535–536
Edgar On Saturday, March 22, 2014 10:08:24 AM UTC-4, [email protected] wrote: > > What is your view on the Little Ice Age being caused by Pacific Rim > volcano's? Incidentally, erruptions have been proposed as the initiators of > the environments suitable for generating plagues, in the 6th century and > again, at the beginning of the 13th century. It gets colder so marmots and > rats dig tunnels and are in closer contact, and thus, easier to spread > bacilli that are bubonic, pneumonic, etc? > > > -----Original Message----- > From: Edgar L. Owen <[email protected] <javascript:>> > To: everything-list <[email protected] <javascript:>> > Sent: Sat, Mar 22, 2014 7:40 am > Subject: Re: The situation at Fukushima appears to be deteriorating > > Richard, > > Here's is new research into one possible contributor to ice ages. Edgar > > Airborne Iron May Have Helped Cause Past Ice Ages > 20 March 2014 2:00 pm > [image: Life from dust. Iron-rich dust streaming from Patagonian > deserts (red plume at left side of image) fertilizes nutrient-poor southern > oceans, thereby pulling planet-warming carbon dioxide from the > atmosphere.]*NASA/Goddard > Space Flight Center, William M. Putman and Arlindo M. da Silva* > *Life from dust.* Iron-rich dust streaming from Patagonian deserts (red > plume at left side of image) fertilizes nutrient-poor southern oceans, > thereby pulling planet-warming carbon dioxide from the atmosphere. > It seems straightforward: Iron-rich dust floating on the wind falls > into the sea, where it nourishes organisms that suck carbon dioxide from > the air. Over time, so much of this greenhouse gas disappears from the > atmosphere that the planet begins to cool. Scientists have proposed that > such a process contributed to past ice ages, but they haven’t had strong > evidence—until now. > “This is a really good paper, a big step forward in the field,” says > Edward Boyle, a marine geochemist at the Massachusetts Institute of > Technology in Cambridge. The research doesn’t directly measure the amount > of dissolved iron in the waters due to dust in previous eras, Boyle says, > but “they provide a much better case for what [nitrogen levels] have done > in the past”—information that can reveal the ebb and flow of ancient life. > The notion that iron-rich dust could boost the growth of microorganisms > that pull carbon dioxide from the air took hold in the late 1980s. During > ice ages, when sea levels are low and broad areas of now-submerged coastal > shallows are exposed, sediments rich in iron and other nutrients would dry > out, the thinking went. Then > ... -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
