Noctilucent clouds

[Erg]

Hi All

Saw a few articles today that related the formation of noctilucent cloud to "Meteor smoke"

Example - http://science.nasa.gov/science-news/science-at-nasa/2012/07aug_meteorsmoke/

Seemed a bit odd to me given the short observational history of this type of cloud.

Would love to hear what people think.

thx

Erg

[andyc]

Seems very odd given the history of observation - had they been meteoroid in origin, they would certainly have been commented upon in UK records from the 18th and 19th Centuries. That they werent reported is powerful anecdotal evidence for the prevailing theory, elaborated upon at the bottom of the post - that they're greatly enhanced by methane release from human activities. Unless there's a good reason for meteor activity to have been progressively increasing through the late 19th and 20th Centuries (and I think astronomers would have noticed), then the meteor theory can't be the whole story.

I could believe that meteor dust provides nucleation sites, while the increasing methane gives the extra water vapour to provide ice for clouds to form and be more common in more recent years. More than 150 years or so ago, there was maybe not enough methane reaching the stratosphere to form the clouds on the existing meteor dust?