A workshop in Potsdam; the Lena Delta

Currently, my work focusses on the Arctic Ocean – that is, the whole Arctic Ocean, a fairly large area. I don’t really focus on the many rivers that supply fresh water to the Arctic Ocean. But in connection with a permafrost conference in Potsdam, a friend and colleague of mine, Vera, arranged a workshop focussing on the Lena River, Lena Delta and Laptev Sea. I thought it would be interesting to join.

In case people are not really familiar with the Lena River or the Laptev Sea, I have embedded a map below.

The Lena River is located in a permafrost region, where the ground is frozen year round. It is the largest of the rivers supplying water to the Arctic Ocean. As the planet is warming, the question is how this area will change, if the water discharge will increase and how the substances it brings with it will affect the Arctic Ocean.

Up until recently, the Russian shelves have been dominated by ice, but in recent years, the ice is breaking up earlier and is formed again later in the season. This means that light can penetrate into the water, which probably mean that more biological production can take place.

But this region is so remote that only a few Russian research vessels visit, and therefore not much is known about the “old normal” or how this is changing. And it is in regions like this that our models can be used to gain more knowledge about what might happen as the ice becomes more scarce.


The view from my hotel window towards the Telegraphenberg where AWI has offices in Potsdam.


Sea-ice in our model

To understand how the Arctic sea ice is changing and how it affects for example the underlying ocean currents, we work with a global sea ice ocean model (FESOM). For the last few years, a lot of effort has been put into improving the representation of the sea ice in the model. One focus has been on the large cracks – or leads, to use the correct name, that we know exist in reality. These are very difficult to capture in large scale models, but my colleague Qiang has now succeeded in modelling these leads and has put a video of the results on youtube. In this run, the horizontal resolution is 4.5 km in the Arctic Ocean. That’s quiet high.