Dreams of Eemian 2

Eemian was the warm interglacial period before the last Ice Age. During that time, many plant and animal species today confined to the Mediterranean region were widely distributed in Central Europe. Vast forests and grasslands were populated by a variety of large fauna today only seen in places like Serengeti.

The far north must also have been quite warm. But what was the climate like in there? And how did the last Ice Age start? Those questions have proved difficult, because very few sedimentary layers survived the glaciations. Recently, researchers in Finland found what is arguably the best window to the Eemian period anywhere in the far north. The sediments are located beneath a bog in Savukoski municipality, northeastern Finland. The area has recently been closely studied because of some highly controversial mining permits.

I was hired to produce two illustrations for the magazine Suomen Luonto ("Finnish Nature"), where the author of recent research about the site's paleoclimate (www.nature.com/articles/s41467…) wrote about their finds. In the final product, they were each paired with the exact same landscape photographed today.

This landscape is from the exact location of the study, called Sokli. Today, it's a bog, but back in the Eemian, there was a rather large lake. It's the bottom sediments of this lake that have been preserved, with thousands and thousands of pollen grains and spores that tell a tale about interglacial climates.

Today, this location is the edge of a treeless wetland, consisting of sphagnum mosses and sedges. On higher land, there are low-growing juniper bushes and scrubby forests of mostly birch and spruce. In the Eemian, the lake was surrounded by mixed forests of spruce, pine, larch, hazel, alder and birch. On the water's edge grew royal ferns (today found no closer than southern Sweden), buttercups, bur-reeds, and yellow waterlilies.