Professor of Geology Minik Rosing

Move a billion tonnes of Greenlandic glacier to the south

You should understand the Earth as a series of connected cycles of different elements. One of the most important cycles is the carbon cycle, where carbon dioxide in the atmosphere is absorbed by plants and microorganisms, which are eaten by animals and finally come back again as CO₂.

The problem is that we have started to tap into this circuit and use the deposits that have taken millions of years to build up. We have used up all of this through the course of a hundred years, and the cycle has therefore gone completely off balance.

It is especially the plants that control the carbon cycle, and they need potassium and phosphorus to survive. In the tropics and subtropics, where it is warm and humid, the minerals in the soil are being dissolved and the nutrients are being washed out into the sea. This leaves soils that are impoverished.

Up north there are plenty of nutrients. The ice sheet grinds the underlying bedrock into a fine powder of minerals and flushes it out with the meltwater off the shores of Greenland. The powder contains exactly the minerals that plants need to grow, but because it is so cold, the minerals are not dissolved and used.

You see this glacial powder everywhere in Greenland. It is all over the place, it is really irritating, and sticks to your rubber boots. It would be a lot more fun if we could transport this broken down material from the Arctic to the tropics and subtropics, get it activated as nutrients and thereby generate more growth. This would both draw down the CO₂ in the atmosphere and reduce the inequality between the Global South and the North, which is mainly due to differences in soil nutrients.

Redistribute to the impoverished Global South

As a geologist, I would say that the big inequality in the world is primarily due to the soil. There is a belt that runs across the northern hemisphere, where there is a large return on agricultural production and good, nutrient-rich soil. You could rectify this inequality by distributing the nutrients more evenly.

It’s of no use globally if you get a fantastic effect from a product that can only be used in a back garden in suburban Allerød.

Minik Rosing

Every year, a billion tonnes of powder washes off the shores of Greenland, and the volume increases with the melting of the ice sheet. It is relatively easy to gather.

Right now, we expect that you need 20 tonnes of powder per hectare of farmland. This means that with one, single, billion tonne of glacier powder we could fertilise an area that corresponds roughly to the impoverished agricultural area of Africa. This is, of course, not practical, but it shows that one local resource can have a global significance.

This makes it a potentially interesting idea because you can scale it as much as you need to. It’s of no use globally if you get a fantastic effect from a product that can only be used in a back garden in suburban Allerød.

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Professor in macroecology, Carsten Rahbek

Throw away the consultants’ reports and start planting (a lot of) forests

We cannot solve the climate crisis by reducing our CO₂ emissions. It is too slow. We need to use the systems of nature to store CO₂ in bottomlands and forests. If I were to spend a lot of money on climate, I would use them for this.

Our land use is extremely wasteful. We squander our resources, and we can therefore achieve a great deal by using our acreage more effectively for agriculture and forestry, while at the same time taking care of nature and doing other climate initiatives.

The IPCC says that we need to preserve existing forests and plant more of them. In Denmark, we have translated this into planting more production forests, which we can fell and burn, and that this is a sustainable use of wood pulp, which replaces, say, coal.

On paper, it means that Denmark has reduced its CO₂ emissions tremendously, because half of our green energy today comes from biomass combustion. However, the incineration of wood leads to more CO₂ emissions per unit of energy than coal. This means that we currently brag about our CO₂ reductions, but they only exist on an Excel sheet.

We have not been radical enough

The climate is indifferent. We have not been radical enough in the things we do. The first step is to stop cutting down our forests and burning them off. It is not a waste product.

When I criticise the way we use forests, I often get the question: How would you plant an optimal climate forest? So I elaborate: We don’t actually know this, and there has been no incentive to find out. We just know that we need to focus on forests that fix CO₂ as soon as possible, and taking land use and biodiversity into account. At the same time, we need to recreate the natural hydrological systems as bottomland, which also holds and absorbs CO₂.

We currently brag about our CO₂ reductions, but they only exist on an Excel sheet.

Carsten Rahbek

I don’t believe that technology can solve the crisis. Projects like this often end up as empty ornamentation.

We need a more holistic approach: We have challenges in terms of clean water on earth, that ecosystems do not function in relation to nutrient circulation, a biodiversity crisis with loss of species and genetic variation, and the climate.

Prime Minister Mette Frederiksen spoke well at a meeting about a new biodiversity strategy at Marienborg on 4 November in front of more than 40 organisations: When we plant forests, it has no effect on biodiversity, it only helps the climate. This is the truth.

Right now, everyone is talking about the need for transformative research. They think it’s about tweaking the same gauges that we are used to. There is no one, singular, solution. But the incremental solutions that focus on the whole of the Earth’s systems can lead to the transformative changes that are really necessary.
It requires strong research environments and research-based teaching if Danish universities are to contribute to global solutions. It is not helpful to have more consultants’ reports.