Back on Earth, what happens to the world’s ocean beaches over the coming decades and centuries may create a much greater technical challenge. The challenge is well documented in The Attacking Ocean , a new book in which British-born anthropologist Brian Fagan points out that 15,000 years ago the oceans of the world were about 120 metres lower than they are today. The beaches of this distant past are now largely submerged, often many kilometres off shore.
In the intervening time, beaches moved inland, sweeping across long-forgotten territories such as Doggerland – today’s North Sea. It was once a grassy plain where paleolithic hunters felled antelope and bison. Their weapons and the bones of their prey are still pulled up in fishing nets today. The stretch between Alaska and Siberia was dry land, too, allowing humans to populate North America.
The cause of this dramatic sea-level rise was the melting of glaciers and vast continental ice sheets that began at the end of the last ice age. In some cases, the change was remarkably rapid. In central Canada, a giant freshwater lake formed that encompassed far more territory than all of today’s Great Lakes combined.
When a larger barrier of ice gave way some 8,000 years ago, the water drained rapidly through the St. Lawrence and coastlines around the world accelerated their retreat.
The process continued, shaping human patterns of settlement and development in ways that we are still trying to piece together. Around 5500 B.C., the Black Sea was a freshwater lake, and its banks the likely site of a thriving population on the threshold of recorded history. Then the rising waters of the Mediterranean broke through the Bosphorus and flooded the region, erasing what may have been one of civilization’s launching pads in a matter of weeks.
Beware the rising damp
The ice age is long gone, but sea level is rising again and that means more changes are in store for us at the beach. A study published last week in the Proceedings of the National Academy of Sciences projects 2.3 metres of sea-level rise for every degree Celsius that the atmosphere warms. And given current rates of fossil-fuel consumption, a global temperature rise of more than two degrees would not surprise most climate scientists. It will take time for the melting ice to catch up. The rising waters won’t happen overnight, but as the study points out, we’re already committed to a whole new shoreline.
In an early era, this would not have mattered much. Humans can usually move fast enough to stay out of the ocean’s way, just as the nomadic hunters of Doggerland did. The difference is that now we’re heavily invested in life at the beach.
What that means for our favourite haunts will vary. Freshwater beaches will not be affected by sea-level rise, although changing water levels in many lakes are another anticipated outcome of climate change.
At the seaside, experts suggest that low-lying cities and harbours will receive most of our attention and resources because of their commercial importance. Beach resort areas, despite the millions in property value they represent, may have to be abandoned, or at least engage in a laborious, strategic retreat.
In a recent piece for Rolling Stone magazine entitled “Goodbye Miami,” writer Jeff Goodell paints a vivid picture of what awaits one of the world’s more celebritized beaches and the city that stands beside it. “Miami embodies the central technological myth of our time,” he writes. “That nature can only be tamed but made irrelevant.”
The facts suggest otherwise.
After thousands of years of witnessing nature do battle at the beach, it seems we’re destined to join the fray – in effect, because we have neglected the warning signs of a changing climate.
But beaches don’t care what humans do.