“Could it be”?, I thought when I saw these patterns on a satellite image. First I saw an example in a book on permafrost (see links below) and after browsing through recent satellite images in Google Earth I found many more. The reason I got excited is that these patterns look exactly like polygonal tundra landscapes that form in permafrost, that I have often seen from aerial images or in real life. It’s a bit complicated to explain properly in a blog post, but under continued freezing and thawing of soils, polygon-shaped networks of ice wedges are built up, which leave amazing patterns in the landscape. We used to have permafrost in the Netherlands during the last ice age. There are a few locations in the Netherlands where relics of these polygonal structures can be found (with a few examples listed in the book mentioned below). Pingo scars are another amazing example of relic permafrost in the Netherlands. I am fascinated by the idea that we can still see these elements of the past in the landscape today, or in a simple satellite image taken under the right conditions. They tell us about wildly different conditions in the past, and provide a link through time to the current Arctic regions.

I can’t say for sure whether these patterns in the landscape are really relics of permafrost and I do not want to claim with any certainty that they are. Similar patterns could have been formed by other, more recent processes that would cause a soil to crack in a similar way. These sites all occur in places with deposits from before or during the last ice age relatively close to the surface, so that the soils in which permafrost once existed are not buried under deep layers of younger peat or clay. So that would lend at least some credibility. The image at the top of this post has been identified previously as a relic permafrost soil (see book listed below). Personally I find the patterns quite similar to what I’ve seen in Arctic regions. But who knows. Only a proper digging campaign with experts will tell for sure 🙂

• van Huissteden, K., & Vandenberghe, J. (2021). Permafrost: Nu en in de ijstijd. KNNV uitgeverij.
• Vandenberghe, J. (2013). Permafrost in Nederland: sporen van vroegere aanwezigheid in sediment en landschap. Gea, 46(1), 10-14.