Tomiro
Jedi
Read this article today, claiming that southern Finland was mostly ice free during the beginning of the last ice age. Still there seems to be quite a lot of unknown factors to it.
_http://hbl.fi/2013-10-27/517981/finland-var-mest-isfritt-under-istiden
_http://hbl.fi/2013-10-27/517981/finland-var-mest-isfritt-under-istiden
Finland was under ice for thousands of years, but parts of the country was free of ice for thousands of years at the beginning of the last ice age. Reijo Pitkäranta thesis nuance the perception of ice early spread.
The ice sheet did not reach southern Finland during the 40 000 first years of the last ice age . The ice crept down to Sydösterbotten but neither east or south from the area around present Kristinestad. According to geologist Reijo Pitkäranta dissertation examined at the University of Turku in the week.
- My results confirm what we have known from the past, but they also nuance the picture of the ice spread, he says.
What is known previously, is that the last ice age began about 115,000 years ago, the ice reached Finland from the west and north , and that it eventually crept southwards and eastwards. The ice covered the entire Fennoscandia , the Baltic countries and the Baltic coast in the final stages before it retreated about 10,000 years ago.
Pitkäranta's contribution to research is the knowledge that ice masses took plenty of time before they flooded into the Gulf of Bothnia. From Ice Age beginning up until 74,000 years ago the ice left southern Finland untouched, aside from the West Coast.
Over the millennia the climate varied in the south from what it is here today to what it is in the mountain region today. Fossil hazel bushes testify that it was pretty mild in between, but there are also signs of permafrost from the period when Finland was not under the ice.
Pitkaranta have researched Suupohja, then Swedish Sydösterbotten plus the nearest Finnish neighboring municipalities in the interior. He states that the ice at the beginning of the Vistula reached there but did not spread beyond that until 74 000 years ago, possibly only 55 000 years ago.
- It looks like the ice edge just reached to Sydbotten, he says.
Glacier Lips move and rub against the ground more than ice masses middle parts. It has left traces which Pitkaranta analyzed .
He can read the ice movement by studying the mountain and soil layers. But neither he nor his colleagues can reliably establish the pace and extent of how the ice spread out later, and how the development went in the next few tens of thousands of years.
- There has been a lot of research into it, but many questions still remain , he says.
However, we know that ice extent was really great at the end of the Ice Age , ie for between 25,000 and 10,000 years ago.
- The ice covered the whole of Finland for at least fifteen to twenty thousand years at the end of the Vistula . When the ice cover was at its greatest, it stretched it all the way down to Northern Germany.