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    A study of over 40,000 written entries in Irish Annals and ice core measurements shows a strong correlation between the occurrence of volcanic eruptions and extreme cold weather in Ireland over a 1200 year period. Data analyzed in this study cover the period from 431 to 1649, during which time up to 48 volcanic eruptions are identified in Greenland ice core records through deposition of volcanic sulfate in annual layers of ice. You can find the study (open access), published on 6 June 2013 in IOP Publishing's journal Environmental Research Letters, at http://iopscience.iop.org/1748-9326/8/2/024035/article. Find out more about how volcanoes can influence climate.
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    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm rep...Read more

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    Atmospheric CO2 Level Tops 400 ppm

    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm repeatedly. Daily levels of CO2 can vary due to weather, and there are seasonal trends as well. The level of atmospheric greenhouse gases continues to increase, now over 120 ppm since the Industrial Revolution began. For more on the Keeling Curve, see http://keelingcurve.ucsd.edu/. Find out more about greenhouse gases and warming.
These wonderfully balanced rocks mark a tomb in Wales.
Click on image for full size
Photo courtesy Diego Meozzi/Stone Pages

Pentre Ifan Dolmen Tomb

The stone structures of England and France are very famous. But, one can also find megalithic sites in such places as Wales, Sweden, Germany, Portugal, Spain, Malta, Russia and the Netherlands. The most popular megalithic site in Wales is Pentre Ifan.

Pentre Ifan is a Dolmen structure. A Dolmen structure is a burial place made out of big stones and those stones are often balancing on top of one another to form an arch or a fort-like structure. Here you can see the one large rock delicately balanced on three more slender upright stones. All of the stones are local igneous rocks. The large capstone weighs over 16 tons and is held eight feet off the ground!

Pentre Ifan can be found near the town of Fishguard in Wales. It is thought to be from around 3,500 B.C. Its name translates to Ivan's Village.

Many times, archeologists and archeoastronomers will look at the orientation of a structure to see if it is aligned towards the setting or rising of the Sun, Moon or certain star on a special day like a solstice. Pentre Ifan isn't typical in orientation. It is aligned north-south. Archeologists and archeoastronomers haven't placed any special significance on this orientation.

Unfortunately, excavation hasn't produced many artifacts at all from this ancient time period. Human remains were not found here, but archeologists are sure that this served as a common burial ground for the people who built it.

Local legend has it that fairies are sometimes seen at Pentre Ifan. They are described as "little children in clothes like soldiers' clothes with red caps." The mystery and majesty of megalithic sites often breed such tales as this.

Last modified September 19, 2000 by Jennifer Bergman.

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