BOOK THREE- PART ONE
Greenlandian Age (11,700 to 8,200 years ago)
In our ongoing journey through the aftermath of the megafaunal extinction, we have reached a pivotal chapter in Earth's history: the Holocene Epoch, this period, which began approximately 11,700 years ago, marked a significant transition from the harsh conditions of the Pleistocene to a more stable and hospitable environment for life on our planet. In this blog post, we will delve into the early phase of the Holocene, known as the Greenlandian Age and discover the critical insights it provides about Earth's climate and ecological evolution.
The Greenlandian Age - A Time of Transition
The Greenlandian Age is the earliest subdivision of the Holocene Epoch, from 11,700 to 8,200 years ago. Its name is derived from Greenland, where invaluable evidence has been uncovered through ice cores extracted from the vast glaciers that blanket this Arctic island. These ice cores contain a treasure trove of information about Earth's past climate and environmental conditions.
One of the most intriguing aspects of the Greenlandian Age is its correlation with the end of the Younger Dryas period. The Younger Dryas was a climatic event characterized by a return to near-glacial conditions after the last ice age, and it had a significant impact on the world's ecosystems. As this period ended, the world was on the brink of a dramatic shift towards a more stable and warmer climate.
Image by Cush, Public domain, via Wikimedia Commons
Greenland ice cores contain layers of wind-blown dust that correlate with cold, dry periods when cold deserts were scoured by wind. Radioactive elements, either of natural origin or created by nuclear testing, can be used to date the layers of ice.
Evolution of temperatures in the postglacial period, after the Last Glacial Maximum, showing very low temperatures for most of the Younger Dryas, rapidly rising afterwards to reach the level of the warm Holocene, based on Greenland ice cores.
Dating the Ages with Ice Cores
Greenland ice cores are like time capsules, allowing us to date past events accurately. Layers of wind-blown dust and other materials within the ice can be correlated with specific climatic conditions. Additionally, radioactive elements, whether naturally occurring or the result of nuclear testing, provide further clues for dating these layers accurately. These methods have enabled scientists to establish a comprehensive timeline of Earth's climate history.
Location of Greenland
Image by Connormah, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Ice Core sample taken from drill
Photo by Lonnie Thompson, Byrd Polar Research Center, Ohio State University., Public domain, via Wikimedia Commons
The Legacy of the Greenlandian Age
As we reflect on the Greenlandian Age, it becomes evident that it represents a time of profound ecological change. The megafaunal extinction, which began at the end of the Pleistocene, had a lasting impact on Earth's ecosystems, leading to the disappearance of numerous large mammals. The subsequent transition to the Holocene, marked by the Greenlandian Age, saw new species and ecosystems emerge as life adapted to a warming and more stable world.
In June 2018, the International Commission on Stratigraphy officially ratified the Greenlandian Age and the later Northgrippian and Meghalayan Ages/Stages. These divisions in Earth's history help us better understand the complex and ever-changing relationship between climate and life on our planet.
The Greenlandian Age, the first chapter of the Holocene Epoch, offers us a glimpse into Earth's transition from the harsh conditions of the Pleistocene to the more stable and hospitable world we know today. As we continue our journey through time, we will explore the Northgrippian Age, the next phase in this remarkable story of climate change and evolution. Stay with us as we uncover more secrets from the Earth's past and unravel the mysteries of our planet's history.