• Title/Summary/Keyword: ancient drought periodicity of 500 years

Search Result 2, Processing Time 0.016 seconds

The Natural Hazards and Drought Periodicity in Korea during the Ancient Times Based on Samguksaki (삼국사기를 통해 본 한국 고대의 자연재해와 가뭄주기)

  • Yoon, Soon-Ock;Hwang, Sang-Ill
    • Journal of the Korean Geographical Society
    • /
    • v.44 no.4
    • /
    • pp.497-509
    • /
    • 2009
  • Records on natural hazards such as droughts, floods, smallpox and attacks of grasshoppers are classified and analyzed during the Ancient Times(BC 57$\sim$AD 935) based on the Historical Records of the Three Kingdoms Age(Samguksaki main record), and influences on human activities and relationships of each natural hazard are studied. The strongest influences on the agricultural productivity were the drought and the influences of floods were weak. The most floods were not destructive hazards because the cultivated lands were distributed in the valley plains and the towns and villages were constructed in the area free from the floods during the Ancient Times. The attacks of grasshoppers have the high frequencies with the droughts. The smallpox of the Ancient Times has no relationships with the dearth, floods and droughts. This means that the waterborne infections happened periodically and after the unification, the infectious diseases happened continuously due to the urbanization leading the concentration of population on the capital. Two cycles of droughts are recognized, and they happened with the time intervals of approximately 500 years during approximately 1000 years in Shilla dynasty.

The Natural hazards and Drought Periodicity during the Medieval Times in Korea Based on the History of Goryeo(Goryeosa) (고려사를 통해 본 한국 중세의 자연재해와 가뭄주기)

  • YOON, Soon-Ock;HWANG, Sangill
    • Journal of The Geomorphological Association of Korea
    • /
    • v.17 no.4
    • /
    • pp.85-98
    • /
    • 2010
  • The natural hazards such as droughts, floods and frost injuries, and their relationships with the social unrest phenomena such as years of famine, smallpox and revolutions during the Medieval times(AD 936~1391) in Korea are compared and analyzed based on the History of Goryeo containing astronomical weather and climate events during the Goryeo Dynasty. Among the natural hazards during the Goryeo Dynasty, the droughts with a period of 4~5 years on average are recorded most frequently. By time series analysis, the most frequency of droughts can be found in AD 286~335, AD 786~835 and AD 1261~1320 during the Ancient and Medieval times. It is suggested that three cycles of the droughts during approximately 1,500 years of the Ancient and Medieval times are recognized and they had happened with the time intervals of approximately 500 years. The frequency of droughts increased in the late Goryeo Dynasty is consistent with those of the social chaos factors such as years of famines, smallpox and revolutions. These records suggest that the natural hazard such as years of famines was one of the most important factors influencing on the collapse of the Goryeo Dynasty, agrarian country.