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14 C increase 775 and 993 AD:

14 C increase 775 and 993 AD:. Aurora observations in ancient times. M. A. Shea. Jull et al., 2014. Possible explanations: Extreme Solar Proton Event Comet Collision - January 773 Gamma-ray Burst – Super Nova. HOW CAN OUR MODERN KNOWLEDGE

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14 C increase 775 and 993 AD:

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  1. 14C increase 775 and 993 AD: Aurora observations in ancient times. M. A. Shea

  2. Jull et al., 2014

  3. Possible explanations: Extreme Solar Proton Event Comet Collision - January 773 Gamma-ray Burst – Super Nova

  4. HOW CAN OUR MODERN KNOWLEDGE HELP IN THE UNDERSTANDING OF HISTORICAL PHENOMENA?

  5. COMMONLY USED GEOPHYSICAL DATABASES Satellite data – IMF, solar wind, proton events (1965-present) Cosmic radiation data (1935 – present) Solar flare reports (1932 - present) Geomagnetic indices (1864 - present) Geomagnetic data (~1828-present) Sunspot Number (~1700 - present) Auroral lists (1000 – present) (some earlier records from ~210 BC to 1000)

  6. SOLAR AND GEOMAGNETIC DATA-SELECTED EVENTS EVENT SOLAR GLE GMS AA* RANK ACTIVITY INDEX 22 Mar 91 28 E No Yes 176 74 10 Mar 89 22 E No Yes 441 1 25 Jul 46 15 E Yes Yes 329 11 28 Feb 42 4 E Yes Yes 168 80 21 May 90 37 W Yes No 19 Nov 49 72 W Yes No 23 Feb 56 80 W Yes Yes 131 166 7 Mar 42 90 W Yes No 29 Sep 89 105 W Yes No 5 Oct 60 N/A No Yes 253 28 AA* Index: 1868-2010

  7. THINGS WE HAVE LEARNED: MAJOR SPEs FROM CENTRAL MERIDIAN ACTIVITY GENERALLY HAVE SOFTER SPECTRA THAN EVENTS FROM THE WEST LIMB. MAJOR HIGH ENERGY ( 4 GeV) SPEs FROM CENTRAL MERIDIAN ACTIVITY ARE RARE. MAJOR HIGH ENERGY SPEs ARE NOT ALWAYS ASSOCIATED WITH A SUBSEQUENT GEOMAGNETIC STORM. MAJOR GEOMAGNETIC STORMS CAN OCCUR WITHOUT A LARGE SPE.

  8. CAN IDENTIFICATION OF LOW LATITUDE AURORA HELP TO RESOLVE UNUSUAL GEOPHYSICAL RECORDS SUCH AS 14C INCREASES IN TREE RINGS?

  9. EARTH'S GEOMAGNETIC FIELD IS RAPIDLY EVOLVING IN GEOPHYSICAL TIME THE GEOMAGNETIC LATITUDE OF AURORAL OBSERVATIONS SHOULD BE CALCULATED FOR THE EPOCH OF THE OBSERVATION

  10. CHANGE IN MAGNITUDE OF THE G(1,0) TERM OF THE EARTH’S MAGNETIC FIELD, 1600-2010 (18% decrease in 400 years)

  11. CHANGES IN THE POSITION OF THE EARTH’S DIPOLE 1000 AD – 2000 AD

  12. CHANGES IN THE POSITION OF THE EARTH’S DIPOLE 0 AD TO 1990 AD

  13. EXAMPLES OF GEOMAGNETIC LATITUDE CHANGES LOCATION 1000 2000 CHANGE S. SPAIN35° N 40° N 5° N SAN DIEGO25° N 40° N 15° N CHICAGO36° N 51° N 15° N EGYPT 34° N 28° N 6° S TASMANIA38° S 50° S 12° S (VALUES ARE APPROXIMATE)

  14. Oct 817 Iraq 816/817 Yemen Oct 879 Morocco 939-940 Syria May 941 Spain Aug 977 Egypt Sept 979 Morocco 991-992 Egypt* Apr 1050 Egypt* 1059-1060 Egypt 1176 Syria* May 1179 Syria Nov 1203 Yemen 1223 Syria* 1264 Syria* 1321/1322 Yemen Nov 1370 Syria 1422-23 Egypt Aug 1449 Yemen 1570-71 Spain * Suspected aurora HISTORIC MID AND LOW LATITUDE AURORA Ref: Basurah, Sol. Phys, 225,2005; JASTP, 68, 2006

  15. ITEMS NEEDED FOR COMPREHENSIVE STUDY OF HISTORIC EXTREME SOLAR-TERRESTRIAL EVENTS ● CONSOLIDATEDMID AND LOW LATITUDE AURORA LIST THESE DATA ARE CURRENTLY SCATTERED ALL OVER THE LITERATURE – IN BOOKS, ARCHIVES AND INDIVIDUAL PUBLICATIONS ● NAKED EYE SUNSPOT SIGHTINGS PRE 1700 ● INDIVIDUAL MAGNETIC DISTURBANCE RECORDS SHIP’S LOGS MAY PROVIDE SOME INSIGHT CARE MUST BE TAKEN WITH THE DATES CITED IN THE ORIGINAL RECORDS.

  16. 14C INCREASES – 774/775 AND 992/993 IF THESE INCREASES ARE THE RESULT OF A MASSIVE SOLAR PROTON EVENT, THERE MIGHT NOT HAVE BEEN A MAJOR GEOMAGNETIC DISTURBANCE OR LOW LATITUDE AURORA, ESPECIALLY IF THE SOLAR ACTIVITY WAS ON THE WEST LIMB OF THE SUN.

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