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  • Irish Chronicles Document Links Between Volcanoes and Weather
    A study of over 40,000 written entries in Irish Annals and ice core measurements shows a strong corr...Read more

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    Irish Chronicles Document Links Between Volcanoes and Weather

    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.
  • EF-5 Tornado in El Reno, Oklahoma Widest Ever Recorded in US
    The EF-5 tornado that hit El Reno, Oklahoma on May 31st was the widest ever recorded in the US, acco...Read more

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    EF-5 Tornado in El Reno, Oklahoma Widest Ever Recorded in US

    The EF-5 tornado that hit El Reno, Oklahoma on May 31st was the widest ever recorded in the US, according to the National Weather Service in Norman Oklahoma. The tornado, which remained on the ground for 40 minutes and reached 2.6 miles across (4.2 km), took the lives of 18 people including storm chasers Tim Samaras, Paul Samaras and Carl Young. For more information on the tornado, visit http://ow.ly/i/2hfDG.
  • 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 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.
Hubble Space Telescope image of Sirius, the brightest star in the sky, and its tiny white dwarf companion.
Click on image for full size
NASA, ESA, H. Bond, M. Barstow

Sirius A - Brightest Star in the Sky

What's in a Name: Greek for "Scorcher". Also called the "Dog Star". Sirius was not visible in the night sky during the summer months, therefore the Greeks thought that Sirius added its heat to that of the sun, producing the warm summer months. The hottest days are still called "dog days".
Claim to Fame: Brightest star in the sky (apparent magnitude=-1.5). In a few billion years it should become a giant and then a white dwarf. Now the surface is enriched in metals. Believe Sirius B (its white dwarf companion) passed material to Sirius A during the process of becoming a white dwarf and caused the enrichment.
Type of Star: White Main Sequence Star (A1 V spectral Class)
How Far Away: 8.7 light years away (2.7 parsecs)
How Big: 1.8 times the Sun's diameter
How Bright: 23 times the Sun's luminosity (Mv=+1.4)
Where to View: In the constellation Canis Major (Star Map).
When to View: January through March

Last modified January 25, 2006 by Travis Metcalfe.

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