Thomas Lee Elifritz

http://arxiv.org/abs/1207.5932

Occurrence of extreme solar particle events: Assessment from historical proxy data, I.G. Usoskin, G.A. Kovaltsov, to be published in The Astrophysical Journal.

Sporadic energy releases on the Sun can accelarate solar energetic particles (SEP) in the corona and interplanetary medium. Such phenomena often lead to solar particle events (SPEs) observed at Earth, that is an important factor of solar-terrestrial relation, and specifically Space Weather.

Cosmogenic nuclide 14C and 10Be data measured in terrestrial archives may provide information on SPEs in the past but this possibility was not fully explored earlier. Accordingly, the probability of extreme SPEs remained grossly uncertain. Here we establish a solid observational constraint on the distribution of extreme SPEs using presently available datasets of cosmogenic isotopes (14C and 10Be) measured in terrestrial archives with sufficient time resolution and quality, and modern models of their production in the atmosphere. We note that the presented resulted is based on terrestrial data and may not well represent the occurrence of solar events, whose geo efficiency is also affected by the relative Sun-Earth attitude.

We have evaluated the probability of occurrence of extreme SPEs based on data of cosmogenic isotopes 14C and 10Be in terrestrial archives, spanning over the time scale from centuries to 11 millennia. We identified four potential candidates for SPEs with overthe last 600 years using annually resolved 10Be data. In particular, the extreme Carrington SPE of 1859 AD contradicts these data. From rougher resolved data we identified 19 SPE candidates over the last 11400 years. Two events appear in different series, ca. 780 AD and 1460 AD making them strong candidates to extreme SPEs. This gives a new strict observational constraint on the occurrence probability of extreme SPEs.

Ok then, that at least superficially explains the year 775 tree ring anomaly.

Heavy space weather it seems. And not all bad space weather is the same, apparently.

I would not want to be on the International Space Station when this kind of shit goes down.

lifeform@charter.net