Historical Course Follows Climate Change: Patterns of the Northern Hemisphere — From Peoples’ Migration until the Industrial Revolution (3<sup>rd</sup>-18<sup>th</sup> Century)

Abstract

This paper relates to the statement that the so-called “Little Ice Age” (RCC 6: 1.350-1.800 A.D.) represents—besides the 8k-Event (8.200-8.000 yr cal. B.P.)—the fastest and strongest onset in Holocene History [1]. Its intention focuses on the correlation of interplaying natural processes (i.e. solar energy variation, aerosols, oceanic currents, volcanism as part of plate tectonics, heat flow) with social/political evidence through the time-span of Peoples’ Migration until Industrial Revolution (3rd-18th Century). The time-span comprises the cool/wet/respectively dry climate phase of the P.M. (260-550), a Climate Optimum (600-1.100 A.D.) owning a final Thermal Maximum (1.100-1.260 A.D.) and the “little Ice Age” (1.350-1.800 A.D.), the latter intercalated by the Sporer Minimum (1.460-1.550 A.D.) and the Maunder Minimum (1.650-1.720 A.D.). Thereby, an average temperature difference of 1.0°C - 2.0°C seems sufficient for incising climatic/cultural consequences [2]. It has become obvious that a Climate Optimum primarily provides constructive life conditions; however with a problematic final as the following “Effect-Chain” tells: balanced agricultural/cultural population growth → rich harvests → satisfying nourishment → health, encouragement → overpopulation under favorable materialistic conditions → increasing stress → lack of food, high prices → revolts → migration. In contrast, cool/wet/resp. dry conditions originate destructive/depressive conditions (see Peoples’ Migration) which initiate the following “Effect Chain”: bad agricultural conditions → poor/no harvesting → famine → disease, growing death rate → social, political revolts, wars → human cruelties with psychic/religious background (inquisition, witch-combustion → general chaos (30 yr-war) → death, migration (maritime endeavors, colonization). Furthermore, it should be stressed that volcanic aerosols play besides the solar influx variation—an important role on climate/cultural change [3]. However, the effects of oceanic currents’ heat flow of Mid-Oceanic Ridges and Hot Spots, as well as Earth-Magnetism and Sun/Earth Geometry are poorly understood in this context (Example: Iceland as hot spot situated on the Mid-Atlantic Ridge having been working since 40 Ma). The Chapter-introducing citations play a challenging role in regard to Science Criticism and touch the so-called 95% Confidence line (accepted realm of causal interrelation and according recommendation to Society [4]).