The 1000 year cycle tends to break down into halves of about 500 years each. Centering on the dates of 375 BC, 30 AD, 460 AD, 955 AD, and 1475 AD, climate was dry and colder than usual. The warm periods were short and were often disrupted by drops in temperature. Midway between these dates, the warm periods stretched out; the interruptions were not as long, and the cold periods shortened. The result is an intermediate cycle averaging 510 years in length.
» Mass migrations were extensive, and all the ancient civilizations collapsed. «
Vandals sacking Rome, 455 AD.
The
beginning of the first of these 500-year rhythms marks an important
place in the history of climate. Prior to 575 BC, climatic cycles were
longer and more extreme than they have been since then. In the two
centuries immediately following, from 450 ta 320 BC, it was warm much of
the time. Two 100-year cycles were almost fused into one. The cold
period between them, at 420 BC, was very short. After that, the cold
periods lengthened. By the end of this 500-year period, at the time of
Christ, there was an exceptionally long cold period.
The cold phase centering on 460 AD, at the end of the next 500-year cycle, was also exceptionally cold. Mass migrations were extensive, and all the ancient civilizations collapsed. There was a long-term downward trend in rainfall. Although there were long cold phases in the 600s and 700s, they were frequently interrupted by silts to the warm side and did not seem to be exceptionally bad. The cold phases of the 800s and 900s were extremely severe, causing many migrations, primarily from the northern countries — especially when conditions began to deteriorate approaching 955, near the end of the 500-year rhythm.
» Civilizations broke up and
new ones took their places. «
Migrants storming European Union borders, 2024 AD.
Subsequently, temperatures warmed suddenly. The 1000s were so warm that trees grew in Greenland. This was the period when Vikings crossed the Atlantic, One of the most severe hot droughts in history occurred in the 1130s. The 13th century saw a long warm period. Then climate began to deteriorate again. While the 14th century was warm much of the time, there were frequent and sharp drops in temperature; often it was very stormy. During several winters, the straits between Denmark and Sweden froze over solid enough to support horses and sleds, Greenland began to freeze. In the 15th century, there was no long warm period.
The next 500-year rhythm terminated at 1475. Subsequently, temperatures warmed up again. The 17th century was so warm that the next 100-year cycle had but a short cold phase, centering on 1655, and this was quickly interrupted by a shift back to the warm side. During the 19th and 20th centuries, climate deteriorated again.
» The 500 year period beginning at 1475 is drawing to a
close. «
Migrants breaching US southern border, 2024 AD.
Climate change? Sure.
Events
of great importance occur every 500 years. Midway between 575 BC and
460 AD, the Roman Empire began its decline as Christianity rose. There
were no strong European civilizations for a long time. On the other
hand, there were very strong Asiatic empires such as that of the Huns.
Midway between 460 and 1475, in the 9th and 10th centuries, a vast
change occurred, again involving mass migrations, These events divided
the Middle Ages into two halves. In the first half, there were brilliant
empires like those of Justinian with its capital at Constantinople,
Charlemagne in the West, and the Arabs in the East. The Arabs moved into
Spain and India, developing brilliant civilizations at Cordoba and
Bagdad. But all this came to an end. These civilizations broke up and
new ones took their places. Following 975, the feudal period developed,
with the growth of principalities that were to form modern European
states. Amazing empires were built by the Mongols in Asia, the Incas in
South America, and the Mayas in Central America. In India and Japan, new
empires were born. The Balkans achieved their Golden Ages during this
period.
All this came to an end in the 15th century. The Medieval
economy, customs, and modes of thought disappeared. With the new
500-year climatic cycle came the Renaissance, the Reformation, and the
building of modern nations — first under absolute monarchs, then under
constitutional governments. This most recent 500-year cycle has
witnessed the awakening of modern art, science, and economics. In these
more advanced civilizations, the common people have, for the first time
in history, come into their own under democratic political and economic
systems.
» The same types of events occurr with almost clock-like regularity. «
The 500 year period beginning at 1475 is drawing to a
close. We are now witnessing many of the same types of events that have
occurred under similar circumstances with almost clock-like regularity
five times before in history. These events are of the utmost
significance for the businessman and student of today — and tomorrow.
Quoted from:
Raymond H. Wheeler (1943) - The 500 Year Cycle.
With a Forecast of Trends Into the 21st Century.