101 Years of Recognised Havoc

In 1922, the British geologist R. L. Sherlock argued that humankind had a major impact on inanimate nature in his work “Man as a Geological Agent”. 101 years later, the Anthropocene Working Group proposed Crawford Lake in Canada as the official site for marking the beginning of a the Anthropocene, a new epoch on the geological time scale.

The scale and character of human activities now rival natural geophysical and geological forces. Lake Crawford happens to preserve some of what we do to the planet very well. From radioactive plutonium released in atomic bomb tests and ash from coal-fired power plants to metals and micro plastics, our sad record of pollution can be read by stratigraphers in the layers of mud deposited over the decades.

As an environmental scientist, I am concerned about the fact that we’ve known about our massive impact for so long, and even though the signs are everywhere and becoming stronger, we’re no better now at doing enough about it to stave off the declaration of the Anthropocene, than we were 101 years ago.

Quite the reverse!

I’ve carried out many beach cleans, visited landfill sites around the world and seen enough debris on the ocean floor to understand the potential for human geological layers, but still, Crawford Lake is so far removed from my experience that the penny only really dropped today.

Seeing is believing and today, I saw Anthropocene sediment with my own eyes.

I’m on the uninhabited island Escudo de Veraguas off the Atlantic coast of Panama with a bunch of Canadians from Students without Borders. We got here on the beautiful tall ship Regina Maris, which is our lovely home for five days. The island’s natural geology is sedimentary: soft mudstone and sandstone bearing shells that give away the marine origin.

Fossil shell revealed by erosion of mudstone.

The crew dropped us off at the southern beaches, where the currents had washed up a lot of plastic debris, the odd bit of fishing net and rope, a couple of cool boxes and plastic sheeting. So far, so (sadly) normal in a region that features a lot of tourism, lacks waste collection facilities in rural areas and unregulated burning of rubbish dumps is a common waste management feature.

Marine litter washed up on southern shores of Escudo de Veraguas

But what really got me was a two meter thick layer of recent sediment made from natural marine debris (coral fragments, sponges, algae), beach sand and terrestrial vegetation, as well as batteries, plastic bottles, plastic bags and rope.

There it was, perched on top of the soft mudstone that makes this island’s natural geology: a human signature that will give rise to ocean pollution once more when it erodes in the future.