I am at Monknash SSSI on the South Wales coast, protected for its abundance of special geology and rare species. A handful of humans and our canine companions are wandering the beach towards Cwm Marcross, beneath magnificent Liassic cliffs just West of Nash Point. We are all separate in our own worlds, though sharing the common experience of listening to the cackling of fulmars on narrow ledges and tracing our way along the shore. The steep, stratified layers of the cliffs are a rhythmic repetition of limestone and mudstone, and formed as a late Triassic desert was inundated by ocean. Molluscan faunas found here by paleontologists have provided a surprisingly detailed record of environmental history, particularly in rarer tufa limestone deposits. They mark the Boreal/Atlantic climatic transition around 8,000 years ago, when rising global temperatures meant further retreat of ice to the North and a rising sea.
At that point in time, Mesolithic humans, dark skinned hunter-gatherers along with, perhaps, a few early settlers, populated what we now describe as Britain only sparsely. The sea had begun to inundate the good hunting grounds of the marshes, lakes and rivers of Doggerland, disconnecting us from mainland Europe. The Welsh shoreline had extended in plains out beyond what we see now as shore, into the Severn Sea (or in Welsh, Môr Hafren). These flatlands were also being swallowed by rising water levels. The newly forming coast would have provided an important source of marine food for early tribal groups, evidenced by middens of cockle and oyster shells discovered in estuarine zones. The temperate post-glacial climate would have encouraged more people to migrate and succeed.
Some 3,500 years before that, at the end of the last Ice Age, marks the beginning of what the International Commission on Stratigraphy accept as the beginning of the Holocene epoch, the geological time period in which we now exist. Climate has been fairly stable over the Holocene, but things are changing rapidly.
As one stands now between the cliffs and the shoreline, it’s as if time is materially trapped in the strata. Listen carefully, and you’ll hear the wind, rain and sea recounting narratives of antiquity, released in little whisps around you. There’s evidence here of glacial retreat, lost ecologies of marsh and woodland communities instead of the hinterland of farms we see today. And there are ancient human stories too, no doubt, the joys and struggles of life, to which I think we still may relate.
Here on the edge of things, magic still dwells, as ever.
Today, intricate honeycomb worm reefs (Sabellaria alveolata), smother wave-cut platforms, thrusting out into long shore drift when tides are low. Their brown planes intersect the water with plumes of sea-spray, the final sigh of waves that may have begun thousands of miles away in the Atlantic Ocean. These are great hiding places for many other intertidal species, part of the reason they are formerly protected from human interference by Law.
It’s a wonder these reefs aren’t smashed to bits by erosion. But they remain firmly in tact, for now, the colonies of tiny worms resiliently rebuilding their feeding tubes with sand particles and shell remains at every chance.
Sadly, if you look closely, you’ll see brightly coloured plastic rings, toys (some even with faces), bottles, caps and inexplicable mouldings that have become entwined deep in the honeycomb. I feed my hand into the reef to pull a few out, and fail. I can’t damage the reef. They are cemented, ensconced behind the living colonies, leeching out their chemicals as they slowly break down with unquantifiable consequences. It’s as if only another epoch of sea erosion and the loss of the worms themselves would ever see them gone.
Moreover, I look around me and imagine worse to come. Oceanographers are now clear that anthropogenic climate change will bring the seas in higher and harder across these shores. More intense storms will wither the roots of all the rare life I observe today. The intertidal ecological zones will become permanently submerged and the cliffs will fall more rapidly back into the high energy waves that batter their foundations. Species will have to adapt as best they can.
I feel ashamed of my own species. It’s all so unnecessary.
In altogether different parts of our Earth’s biosphere, as part of the International Commission on Stratigraphy, there are a number of academics scattered in universities worldwide who call themselves the Working Group on the Anthropocene. Anthropocene is a term first used by atmospheric chemist Paul Crutzen and ecologist Eugene Stoermer in 2000 to delineate a ‘present time interval’, yet to be fully sanctioned or determined, in which many geologically conditions and processes are profoundly altered by human activity. The evidence, however, is mounting.
The Group plans to assemble later this year to decide whether the Anthropocene is to be ‘set in stone’. The case will be reviewed by the International Commission on Stratigraphy and, if approved, the new epoch will have to be ratified by the International Union of Geological Sciences before formal adoption.
A paper published recently in Science provides further evidence of human impacts upon the lithosphere, the rigid outer part of our planet Earth. Various biogeochemical cycles have ensured our pollutants have reached far and wide. The plastic I find trapped today in the honeycomb worm reefs are only what I can see with my eyes. There are far more profound changes occurring beyond my senses that not only future geologists thousands of years from now (indeed, if our species has rallied), might discover in core samples and geochemical surveys, but modern Earth scientists are already uncovering.
It appears there are indicators in recent lake sediments in Greenland, which distinguish them from the rest of the Holocene epoch,
“The appearance of manufactured materials in sediments, including aluminum, plastics, and concrete, coincides with global spikes in fallout radionuclides and particulates from fossil fuel combustion. Carbon, nitrogen, and phosphorus cycles have been substantially modified over the past century.”
“unprecedented combinations of plastics, fly ash, radionuclides, metals, pesticides, reactive nitrogen, and consequences of increasing greenhouse gas concentrations. In this sediment core from west Greenland (69˚03’N, 49˚54’W), glacier retreat due to climate warming has resulted in an abrupt stratigraphic transition from proglacial sediments to nonglacial organic matter, effectively demarcating the onset of the Anthropocene.”
Salutary stuff. There’s still much debate about the precise point in time the Anthropocene is supposed to have begun. Some argue it should be traced back to the Neolithic conversion from human hunter-gathering to farming, whilst others look to the more recent Industrial Revolution and the beginning of the fossil fuel era and greenhouse gas emissions. The Great Acceleration” since the 1950s, a period of exponential economic growth and consumption of resources, looks to be a prime candidate, and even the dropping of the first nuclear bomb in New Mexico 1945 has been suggested. The ‘Subatlantic’ is the current climatic age of the Holocene. It started at about 2,500 years ago, but the data sets will surely no longer be the norm as we move forward in time. Even in the UK, we are already facing what meteorologists describe as ‘unknown extremes’ in terms of climate volatility.
Perhaps, by declaring a brand new geological epoch because of the impacts of one species, our own, the act itself will induce a re-imagining and re-forming of human-Earth relations. As a part of nature, we are cheating ourselves if we think our own dominion above all other life remains the route to living within our planetary boundaries instead of exceeding them as we do. We share one biosphere, we need to respect the precariousness of our situation, but remember our responsibilities to our evolutionary kin, both human and non-human.
Back to Monknash, and the tide is turning; significant, as it’s the second largest tidal range in the world after the Bay of Fundy in Eastern Canada. As I look West along the vista of cliffs, the light is fading to pink with the onset of evening, and it’s time for me to return home. I can’t help feeling that we could somehow learn from this coast as it reveals secrets of past changes whilst recording new climates and adapting species of today and into the future.
This particular section is declared by Cardiff Vale Council to be unprotected from the onset of the sea, left to ‘natural’ processes which would have otherwise shaped our coasts for eons. We are, of course, part of nature, so our impacts may also be perceived as ‘natural’, though does not, I’d assert, make them anymore just. In other places nearby, where humans reside near current sea levels, there are, at least some plans afoot to provide defences and support. But we collectively haven’t the funds to fend off the mass of an expanding ocean for long. I can only hope that 2016 and the declaring of the Anthropocene Epoch will not go unnoticed for real change is now long overdue.
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