#drumlin

Two friendly Irish donkeys in a colourful countryside scene.

Ireland would once have been home to many thousands of working donkeys until the age of the tractor.

Snow Flakes

Layer upon layer of shimmery white snow built up and packed tightly together, it creates ice-crystals that with time get even more dense and compressed. When these icy conditions continue for many years a glacier is finally created.

These are the origins of the Ice-Ages, the enormous masses of ice that so significantly influenced the Earth’s geology.

The northern lands were shaped and modified during numerous periods of glaciation and deglaciation forming fjords, moraines and eskers. But it was not only glaciations that played an important role in Nordic countries geological history, other dramatic events like earthquakes and volcanoes have also left their trails.

The landscape we see today is a mosaic of shapes originating from different time periods, the oldest about 3 billion years ago, to the most recent which is still being formed.

Amid these times Scandinavia, Northern Europe and Northern parts of Central Europe, not to forget North America and various other parts of the world, were uninhabitable.

It was first after the Ice-Ages that humans started to settle down in these, earlier deserted places.

The first pioneers arrived in Scandinavia after the end of the last Ice-Age (8.000 B.C) when warming temperatures first made the countries livable.

Most of the “new settlers” were fishermen and/or hunters.

Fjord, Norway.

The Fjords

There is actually not one "Ice-Age" but there have been up to 50 Ice-Ages over the last 2.6 billion years.

Glaciers are only formed on land and differ profoundly from ice layers formed on the surface of water, as lakes or seas.

Once a glacier becomes more than 25 metres thick it starts to constantly move under its own weight because of gravity.

There are still remains left in Norway from the last Ice-Age as not all the glaciers completely melted.

Most of the remaining ones can be found in mountainous regions, where it is colder.

When the glacier started to melt, the stones and gravel from the eroded bedrock that had been stuck in the ice of the glacier for thousands of years got loose and was carried away with the ice streams creating the U-shaped valleys.

Later when the glacier melted and partly disappeared, the sea level rose considerably, filling the valleys with water and the fjords were born.

So, in short , the fjords are essentially the glacier that melted away and left behind an U-shaped valley scraped out of the mountain.

The fjords are really deep, sometimes as deep as 1.000 metres below water level, and even more so inland.*see end article.

The debris carried away by the melted water was pushed out until the ocean entrance of the fjord, creating a kind of threshold, making the water inside the fjord deeper than by the entrance to the ocean.

This in turn causes extreme currents and large saltwater rapids, Norway is known to have the world’s strongest tidal currents.

Esker, Norway.

The Eskers

Like fjords, eskers are also a distinct feature of landscapes shaped by icing.

Eskers can be up to hundreds of metres in length, they generally run parallel to the direction of the melting ice, which means south-north direction.

There are two basic types of eskers depending on if the tunnel or ice hollow , in which the ice- stream ran,were formed over or under the water level.

Thus, they are either supra aquatic or subaquatic eskers.

As the ice melted, ice- streams were formed inside the tunnels or hollows, the ice-streams dragged with them big stones, small stones, pebbles,gravel and sand.

When transported inside the tunnels the stones were grounded and rounded against each other until they became nicely round in shape.

Once the particles exited the tunnels the speed slowed down, consequently the heavier materials like stones and pebbles fell to the ground first, afterwards the gravel, lastly the sand and silt creating various layers.

This is the reason why we find the coarser, rougher materials in the bottom of the esker.

As the ice-stream coiled or curled its way under the melting glacier an esker is mostly S-shaped.

As a comparison and probably as close as we can get to an Ice-Age are the two ice covered poles.

Antarctica.

The two poles

Arctica and Antarctica have many similarities but they are also “polar opposites” metaphorically as well as literary.

One of the most significant differences is that the Arctic is land surrounded by sea, and it is connected to various continents (Europe, North America and Asia) making it more accessible.

Moreover the Arctic region contains a variation of landscapes like plains, mountains, some very large rivers, lakes, rolling hills and huge stretches of tundra.

The Antarctic (meaning opposite to Artica) is one big, isolated continent unconnected to other continents.

It is 98% covered in ice and it is the world’s biggest resource of drinking water.

The Antarctic landscape consists predominantly of icy mountains, glaciers or smooth ice sheets.

As the Arctic is not as cold as the Antarctic there are more flora and fauna to be found there.

Actually the Arctic is one of the richest and most diverse wildlife habitats on Earth.

It is home to a wide range of plants and animals from the big mighty white bear, the beautiful Arctic fox, the agile sea lions to the smallest micro plankton.

One can not help but wonder, can there be enough food for all these animals and the indigenous people who also make up a part of the ecosystem?

Iceland.

In March, when the sun begins to rise low in the Arctic horizon, when the first sun rays come to give new hope to the frozen, icy wilderness one thing is sure, it will not set until six months later.

In this bright, short , half year period everything in the ocean works on a 24 hour overtime schedule, to make up for the coming half year long hiatus.

The explosion of life supports the entire Arctic and its inhabitants for a whole year.

But it’s not only underwater where the fish and marine life profit from the overproduction, even above the ice sheet separating the two worlds, the wild animals living here also get their foods from the food chain and benefit from the sudden boom of photosynthesis production.

Aurora borealis.

The Auroras

From the depth of the colourful, icy oceans to the cold, dark winter skies where a colourful phenomenon called aurora takes place.

Aurora occurs in both hemispheres without any significant difference except for the location, around the North Pole it’s called aurora Borealis also known as the northern lights and is best observed between December and March.

Meanwhile in the Southern Hemisphere it’s called Aurora Australis (southern lights) and can be seen from March until September.

Auroras display vibrant lights in different shapes like spirals, rays, curtains or energetic, electric flickering lights covering the entire sky.

Scientifically speaking auroras are interactions between Earth’s magnetic field and charged particles emitted from by the sun.

Fascination and mystery around this beautiful scenery have long spread myths and legends amongst the Nordic people.

In Icelandic folktales the northern lights are most closely related to childbirth, as a blessing or a miracle.

In Sweden and Norway the myths about auroras are closer connected to religion and the Viking gods. Auroras were thought to be reflections of the “Valkyries” armour as they were led to Odín or Valhalla (paradise).

In Finland the name of the Northern Lights is “Revontulet” (Firefox), the name comes from the rather beautiful myth that arctic foxes produced the aurora.

These foxes would run through the sky so fast that when their large, furry tails brushed against the mountains they created sparks that lit up the sky.

A slight variation to this story tells that as the firefoxes ran, their tails swept snowflakes up into the night sky, which caught the moonlight and created the aurora.

This version also helps explain why the lights were only visible in winter.

Arctic Fox.

African Ice-Ages

From the extreme north to the furthermost south where, while exploring the desert countries in South Africa geologists have discovered a peculiar land formation.

The flat desert floor is replete with hundreds of long, steep, oval shaped hills.

The landscape in South African countries is shaped by drumlins, a kind of hill found in places once covered in glaciers, an abnormal characteristic for desert terrain.

There is no doubt this region experienced glaciers and Ice-Ages.

The word drumlin is a derivation of a Gaelic word for a rounded hill.

Drumlins are oval or egg shaped hills, largely composed of glacial drifts of ice flow.

Drumlins are considered subglacial bedforms. * see end of article.

The Namibian drumlins in particular are interesting, as normal glaciers leave behind a steady pattern of growing and melting, the once in Namibia showed larger grooves which means that the glacier must have melted at an enormous velocity.

These grooves showed the first evidence of an ice- stream in Southern Africa about 300 million years ago.

The ice carved long grooves in the rock, as it moved.

It was not only that there was ice there but there had been an ice-stream and it had moved really fast.

The findings also prove that South Africa was located over the South Pole during this time period.

Drumlin in Namibia.

Snowflakes

All this reminds us about how it all started. One little snowflake and then another one and another one…..

Snowflakes are delicate, glamorous and elegant with an enormous variation in shape, size and colour.

An original and unusual recreation is watching snowflakes.

Snowflakes do come in different types, sizes and a whole variety of shapes.

By looking at them, classifying them and giving them names you will be more familiar with the snowflakes and their world.

It is an innovative and amusing activity that can be done with friends, family or with your loved one.

Can snowflakes be classified?

It is not easy because it is somewhat a matter of taste, there will never be a precise way to define all the different types but as a guide you will find below a 35 type classification grid.

Next time you are stuck at home due to snow, worry not, instead enjoy your time by watching snowflakes!

Snow Flake.

*The most widely accepted theory of how a drumlin is formed, is that the forward motion of ice , can in part, be accomplished by deformation of the soft underlying sedimentary bed. It could also be a result of flooding underneath the ice sheet or glacier.

*Sogne fjord, Norway reaches as much as 1.300 metres below sea level.

Information obtained from;

First description of subglacial megalineations from the late Paleozoic Ice-Age in South Africa.

Materials provided by Virginia University.

35 Snowflakes: