Part 2: Climate and Human Migration: Airyan in Eurasia and on the Iranian Plateau;
Part 3: The Early Airyan Civilizations on the Iranian Plateau;
Part 4: Achaemenid Empire: Haxāmaniš Empire
Part 6. People of Airyana Now
Part 7. Historical Aryan (Airyan) Women
Part 8. Airyan People: Taleshan
Introduction
The thesis of this work was to explore the consequence of the climatic changes during the last 100,000 years affecting Airyan (a.k.a. Aryan), one of many groups of Homo sapiens.
In general, emigration out of Africa during the last 100,000 years could be divided into four distinct periods:
1. From 100,000 years ago to the 30,000 years ago, different groups of Homo sapiens, including the Neanderthals, migrated out of Africa into Asia and Europe. Many Airyans today carry the maternal genome (mtDNA) reflecting this early emigration (mtDNA U5 genome).
2. From 30,000 years ago to 10,000 years ago, they back migrated out of cold and glaciated European and Asian territories to warmer regions in Southern Europe, Northern Africa, Eurasia, and the Iranian Plateau. Those who had returned contributed to the existing population of Eurasia, including Airyana.
3. From 10,000 years ago to 2000 years ago, Homo sapiens relocated within European, African, and Eurasian territories escaping from the hot and drought conditions into more hospitable regions of Europe and Russian Steppe.
4. From 2,000 years ago to the present, Homo sapiens migrated as a consequence of economic and social factors in addition to the adverse climatic change. The adverse climatic conditions resulted in the mass emigration of people within west-central Asia into the Middle-east and Eastern Europe.
This work is divided among the following investigations:
1. The climate from 100,000 years ago to the present time;
2. The Genesis of Airya;
3. Migration of the Airya people (Airyan);
4. Geophysical environments lead to the development of language and culture among Airyan people.
The thesis of this work was to explore the consequence of the climatic changes during the last 100,000 years affecting Airyan (a.k.a. Aryan) one of many groups of Homo sapiens.
European-Eurasian Glaciation
The Environment following the maximum Glacier
Persian Leopard
European-Eurasian Glaciation
Approximately between 110,000 to 12,000 years ago, massive continental glaciers covered greater global areas including Europe and Eurasia (Figure1). The oceans water level dropped by about 150 meters. The maximum extent of glaciation was approximately 22,000 years ago. During this period, local ice fields capped the mountains in Europe, the Caucasus, Turkey, and Iran. Glaciers had stored a great body of fresh water in the mountains and in ice sheets.
Figure 1: Europe: European ice sheets were miles high in many places. The glaciers stored fresh water in ice.
Figure 2: A map of Europe and Eurasia
A comparison of information in Figures 1 and 2 would indicate the massive extent of the glaciation in Europe.
The Environment following the maximum Glacier
a. Persian Gulf
Western Iranian Plateau is covered with mountain ranges mostly running in a northerly direction. The regions between the mountains create many forested river valleys. The Zagros Mountains range begins in northwestern Iran and roughly corresponds to present Iran's western border, and it spans the whole length of the western and southwestern Iranian plateau, ending at the Strait of Hormuz. The highest point in the Zagros Mountains is Ghashmastan (4435m), in the Dena.
Arvand Rud "Swift River" (Shatt al-Arab) is the principal rivers between Iran and Iraq; it discharges into the Persian Gulf. The river is 200 km (120 mi) in length and is formed by the confluence of the Kārun, the Euphrates, and the Tigris rivers. Karun is 450 miles (720 km) long and originates in Zagros Rangeit. Kārun is Iran's only navigable river.
Homo sapiens passed through Strait on the Red Sea crossing into the Arabian Peninsula and entered into the Iranian Plateau (Fig. 3). The Persian Gulf today has an average depth of 50 meters and a maximum depth of 90 meters. The Persian Gulf stretches 989 kilometers from the present boundaries from Iran and Iraq to the Gulf of Oman. At the narrowest width, the Strait of Hormuz is about 56 kilometers wide.
Figure 3: A map of Eastern Asia and North Africa
However, at the maximum glaciers period, the entire Persian Gulf was a dry shallow valley (Figs. 4 and 5) with several small lakes at the lowest valley floors. These lakes received the waters of the Arvand Rud.
The glacial retreat had a profound effect on landscapes in many areas that were covered by ice at the Last Glacial Maximum. Melting of ice on Zagros Mountain range increased river flow into the Karun. The melting of glaciers in the Taurus Mountains increased river flow in Tigris and Euphrates. These increases expanded the size of the local shallow lakes within the Persian Gulf valley (Fig. 5).
In addition, as the glaciers melted in all over the globe, the ocean water level slowly increased to the present level. The combined sea level change and the expansion of the lakes broke the soil dam at Hormuz (Figs. 4, 5). The water from the Gulf Adan intruded into the Persian Gulf valley. Figure 5 shows the lakes in the Persian Gulf Valley 12,000 years ago. It also shows the intrusion of water from Gulf Adan into the valley.
Figure 4: The figure shows the lakes in the Persian Gulf Valley 18,000 years ago.
Figure 5: The figure shows the lakes in the Persian Gulf Valley 12,000 years ago. It shows the intrusion of water from Gulf Adan into the valley.
The Persian Gulf level in parallel with Gulf Adan steadily rose along with the ocean reaching to today’s level by about 6000 years ago (Figs. 4 and 5). The Persian Gulf valley had a thriving population prior to 12000 years ago. The valley may have supported early humans for over 100,000 years. As the level of water in the valley rose, the population within the valley left the valley for higher grounds and escaping the advancing water. Those who left the valley could have been the ancestors to Elamite and Sumerian.
b. Caspian Sea
Caspian Sea (Figs. 3, 6) is the world's largest inland sea. At present, it is third as salty and about ninety feet below oceans sea level. It is over three thousand feet deep at its lowest depth.
Figure 6: Caspian Sea. During the glacier period, the sea level was low and the passage was narrower. The melting of glaciers created rivers and altered the landscape and altered the Caspian Sea, Ural Sea, and the Black Sea.
Caspian is a closed sea, i.e. it does not have an outlet. The sea level is mostly controlled by inflow from the Caspian watershed and surface evaporation. Among more than 130 rivers or streams that discharge into the Caspian Sea, the Volga River contributes about eighty percent of the water. It enters the Caspian Sea through the Volga delta (Fig. 7). The Ural River flows in from the north, and the Kura River flows into the sea from the west (Figs. 7, 8).
Figure 7 shows the Caspian Sea watershed area.
Figure 8: The watershed in the east of Caspian Sea.
The Amu Darya River and the Syr Darya farther to the north had frequently changed course and discharged into the Caspian through a now-desiccated riverbed called the Uzboy River.
Figure 1 shows the extent of glacial ice about 20,000 years ago. During this period the glaciation reduced parts of western & central Europe to the polar desert. Melting of the glaciated ice did not begin until about 11-12,000 BCE. A significant volume of the fresh water released from the melting of the ice flowed into the Caspian watershed. The rivers increased in volume and added to the inflow to the Caspian Sea. Figures 9 and 10 show the size and the extent of the Caspian Sea and the Black Sea. The level of water in the Caspian Sea increased by about 50 meters (160 feet) above the present-day level.
Figure 9: The change in the Caspian Sea and the Black Sea before and following the melting of the glaciation.
Figure 10: The change in the Caspian Sea and the Black Sea following the melting of the glaciation
The rise was extremely rapid and the Caspian basin could not contain all the flood water. The change in the Caspian Sea level allowed the excess water to flow through the Kuma-Manych Depression and Kerch Strait, into Sea of Azov and the ancient Black Sea basin.
By 12,000 years ago, the Black Sea level increased by some 60 to 70 meters (200 to 230 ft.) 20 meters (66 ft.) below its present-day level. A large segment of the flooded Black Sea Basin was previously forested and had settlements of hunter-gatherer Homo sapiens. The population had to leave the area to escape the flood.
The Climate Post Glaciation
The period for the oceans to reach the present level was about 6000 years after the end of glaciation. The forces affecting the climate are many and include the large scale oceans currents. El Niño Southern Oscillation and La Niña cause global changes in both temperatures and rainfall.
The African Humid Period, from 11,000 to 5,000 years ago, ended abruptly, with Sahara drying back into desert within a span of one to two centuries.
About 7,000 years ago the climatic change in the North Africa and Western Iran adversely decreased the rainfall and precipitation. The transition to today's arid environment occurred in several periods: from 6,700 to 5,500 years ago, and again a severe change from 4,000 to 3,600 years ago. About 2,200 years ago another abrupt change in the climate had adverse effects on the biomass. According to carbon-14 dating, summer temperatures sharply increased, and precipitation decreased. These events were responsible for changes in the socioeconomic of the periods.
The Ice Man, a preserved hunter was exposed to a retreating glacier in the European Alps. He has trapped very abruptly in the glacier ice about 5,200 years ago. About 4,000 years ago the regions in India, Pakistan, Nepal, and Bangladesh had an abrupt climate change. The climate adversely affected the ancient civilizations in these regions; about 5,200 years ago, the population in these regions abandoned the towns and migrated to the East.
The plot in Figure 11 shows the variations, and relative stability, of climate during the last 12000 years. At any particular site, large changes may occur without correlating to similarly large changes at other sites. The Younger Dryas was a period of cold climatic conditions and drought from 10,900 and 9500 BC. There was a Little Ice Age during the period of 1300 AD to about 1850 AD.
Figure 11: The change in the average ambient temperature since the end of the last glacial period. The data sources are provided in the following reference:
https://commons.wikimedia.org/wiki/File:Holocene_Temperature_Variations.png
The hunter-gatherer Homo sapiens were dependent on grasslands and forested areas that nurtured the sources of their food. The major consequences of low precipitation and high ambient temperature were adverse effects on terrestrial biomass, decreasing or eliminating the grasslands and the forested areas.
Dedication and Acknowledgement:
This work is based on works published by scientists in many inter-related fields. I am dedicating this work to them.
I have listed the references for some of these works within this publication.
Part 2: Climate and Human Migration:
Airya in Eurasia and in the Iranian Plateau