Ice Ages

The first life on Earth was in the form of bacterial algae, which are photosynthetic organisms. If it were not for them we would never have had oxygen, and without oxygen we would never have had fire.

Life has been extinguished during the 4 ice ages this planet has undergone (rhythmically every 41,000 years). They occur because sunlight shining on the North Pole is insufficient and an ice age ensues. The Earth interacts with the Sun, Moon and other planets in such a way as to evolve seasons which have set the rhythms of our existence. As the Earth tilts on its axis the North Pole tilts toward the sun in summer and away in winter. Around every 23 millennia (1000 years is a millennium) the Earth wobbles (Milankovitch wobble) until the Earth changes its angle of tilt between 22 and 25 degrees cyclically every 41 millennia. It is currently at 23.5 degrees. It takes all those thousands of years to settle back to its ideal state. During that period snow and ice build up in the polar areas and create massive ice sheets. More tilt results in colder winters and hotter summers. Conversely, less tilt will lead to milder winters and cooler summers. As the snow and ice build at the polar region during an ice age, the land closer to the pole also builds more snow and ice. It is thought now that CO2 was the driver which triggered the acceleration of the melting of the last ice age.

Snow and ice reflect the sun’s rays back into space (the albedo effect), leading to an acceleration of cooling. Albedos are on a continuum from 0 (complete absorption) to 1 (complete reflection). As we know our planet is heating up due to CO2 and methane accelerating the process, and that reduces ice and snow, even some cloud cover. We are seeing glaciers retreating much faster than was predicted only a few years ago (although for some reason they are not doing so in the Himalayas). Without the reflection of the sun’s rays back out into space, the sea and land absorb the heat, which intensifies the heating process. Even if we can instantly stop the emissions of greenhouse gases, the heating up will continue as it has a momentum.

Since 1850 to 1980, around 90 to 120 billion metric tons (90-120 trillion kilograms) of carbon dioxide were released into the atmosphere, and an estimated 165 billion metric tons of carbon dioxide were added to the atmosphere by industrial nations through the burning of coal, oil, and gas. Fossil fuel burning has been estimated to release 5.6 gigatons of carbon into the atmosphere each year. Another 2.4 gigatons of carbon per year (about 30 percent of the total) is contributed from burning tropical forests. When, in 1997, Indonesian farmers used slash and burn techniques the result was greater greenhouse gases released than all the cars and power plants in Europe emit in an entire year.

Archeo-geneticists analysed large quantities of mitochondrial DNA from Europeans who belong to two major lineages named J and T. It is known that these haplo-groups originated in the Middle East and migrated to Europe around 9,000 years ago, as the Ice Age drew to a close.

Stone Age man existed in the Middle East around 10,000 years ago (Neolithic Man). Skara Brae in Orkney is the site of a group of ten houses dating back to the Neolithic Period, and thought to be lived in during 3180 BCE–2500 BCE, the people surviving for at least 600 years there.

A few thousand years ago. the Middle East was also where the wolves of the area were bred by the people to become our domesticated dogs here in Europe starting with the chow chow, Shar-pei , the Siberian Husky and the Afghan hound. As a dog lover that fascinates me. We have five dogs currently, collies, Labrador, terrier and daschund. Their genetics go back to the Middle East, and, as a European, most probably I do too.

Our ancestors would have walked across land now submerged by seas and oceans, but then, as the ice receded, coastlines were extended. These form the continental shelves which are now measured to identify fishing rights and oil drilling territorial sovereign ownership.

Example: The Celtic Seas include the shelf area west of Scotland – ICES Subarea Via is quoted in the Irish Statute Book S.I. No. 501/1998 — Herring (Prohibition on Fishing in Ices Divisions Vb, Vian and Vib) Order, 1998. “the specified area” means ICES Sub-area Vb), ICES Sub-area VIa, North of 56 00’N and in that part of VIa which is situated east of 07 00’W and North of 55 00’N, excluding the Clyde and ICES Sub-area VIb.

As the ice retreated the landscape was gouged and moulded by the vast water forces which shaped it so dramatically to become the land on which I walk on a daily basis. Over the thousands of years since the process of melting began, the weather has wreaked its changes too. I never fail to feel overwhelmed by the visual and tactile impact I experience living here.

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About borderslynn

Retired, living in the Scottish Borders after living most of my life in cities in England. I can now indulge my interest in all aspects of living close to nature in a wild landscape. I live on what was once the Iapetus Ocean which took millions of years to travel from the Southern Hemisphere to here in the Northern Hemisphere. That set me thinking and questioning and seeking answers.
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