Excavator transferring rock from a ship on York River
I reported last year about shoring up Jamestown Island to avoid incursions from the James River. Simple measurements with a conductivity meter showed pools across the island are brackish from tidal surges and hurricanes. That explained why only a few relatively salt-tolerant amphibians are present in an environment that is otherwise ideal for them.
The Colonial Parkway is a 23-mile scenic highway connecting Jamestown and Williamsburg on the James River side of the Virginia Peninsula and Yorktown on the York River side. This year it’s the turn of the eroded banks along the York to be reinforced. Engineers have brought in granite blocks for laying along the route. They need a lot of heavy equipment—several large excavators, trucks, and barges moored offshore for a small ship to transfer rock.
It’s necessary work for preserving American heritage but does nothing to mitigate climate change. In fact, it does the opposite and that’s a paradox. As we grasp the seriousness of unfolding crises at sea and on land, the extra fossil energy used to protect nature and property emits more greenhouse gases.
Historic Jamestown celebrated Archeology Day today with various events and demonstrations to make history seem more authentic. Artifacts discovered on the island in the past 30 years give glimpses of how the first English colonists lived before they moved to higher ground in 1699 to make Middle Plantation their new capital (Williamsburg). Today’s program discussed the people (Native Americans, Whites, Blacks) and their occupations but nothing about the hydrology that dominates and determines who can live there.
I was reminded of the island’s fragility this summer when drawn to the James riverbank by a loud noise. Workmen were loading blocks of granite from a barge to build higher defenses from inundation.
The English colonists arrived at the worst possible time in 1607. A serious drought lasted from around 1606 to 1612, the driest years in eight centuries. The James River was much lower than today without refreshing rain in the watershed. The water at Jamestown was more saline, around 16 ppt compared to a tidal range of 3 to 10 units today (and 35 at the river entrance). The drought offered a slight compensation by encouraging the spread of oysters further upstream for human harvesting.
Measuring the conductivity of ponds across the island, I found the water remarkably salty everywhere. The low-lying island is probably washed over by occasional hurricanes. That helps to explain why there are fewer amphibians than expected (few species tolerate salt). The environment is getting more hostile from sea-level rise.
If Archeology Day is still held at the end of this century it will be sad. Island visiting will be virtual because the excavated and reconstructed sites, including the original fort, will be underwater by then. Children who came today should keep their photos for their grandchildren to see and sigh.
I’m still reeling about our climate crisis/ emergency. We hear the urgency confirmed over and again by experts. Threats imagined far over the horizon that we thought we’d never see in our lifetime are now in plain sight (fires, inundations, etc.). This is probably the biggest shock in my life, and certainly the most momentous.
I am grappling for metaphors of how this makes me feel. I have an old memory of a day walking on the ‘downs,’ the rolling grassy hills in southern England. I headed toward a thin blue-gray line of English Channel on the horizon. The coast was far off but after an hour I had drawn close enough to see choppy waves and white caps. I was eager to watch the tide rolling over the beach and sanderlings snatching a landed morsel by pattering bravely ahead of its foamy front. Still striding on I didn’t realize I was getting close to the cliff edge. There were no cues. I stepped back with a deep breath when I almost stumbled on the precipice and giddily gazed down 300- sheer feet of crumbling white chalk.
Seven Sisters, East Sussex
Likewise, I feel panic about global warming, although my metaphor fails to account for how we can’t step back to resume life as usual, forgetting the brink, as I did after heading back from the downs.
I am now casting around for other memories. When did I become conscious of climate change, and when was I persuaded it was anthropogenic? I ask because people draw a line in the sand at different dates, and some still refuse to. If climate denial is a symptom of a ‘post-truth’ society, it is ironic because science marches with ever greater confidence.
When I checked the history of the greenhouse effect, I found it was known in the Victorian age. Later in the century the Swedish scientist Arrhenius (vaguely remembered from school chemistry) estimated a doubling of atmospheric CO2 would increase average global temperatures by 5°C, not a bad estimate considering the primordial state of atmospheric science. Some 30 years later, a British scientist celebrated the prospect of warming by CO2 emissions because that would improve the dreary national climate! Smog was the greater concern then, although it is evanescent compared to greenhouse gasses.
The winter of 1962-63 was so severe my igloo in our London garden didn’t melt for six weeks. No subsequent year has been so relentlessly cold. In the 1970s there was talk of planetary cooling and a new Ice Age. No more! It was a statistical blip that briefly fooled us about rising trends, like losing sight of the sea for a moment after stumbling in a rabbit burrow on the downs.
By the 1980s there was serious talk about global warming, and I became a believer. I even published my convictions in a Church of Scotland magazine in 1989, the year before the first report of the Inter-governmental Panel on Climate Change. My only satisfaction was the invitation to speak at Women’s Guild meetings at which I showed a home-made model of the greenhouse effect. It was moving to meet elderly women in the audience who worried about our human legacy for the planet; they were streaks ahead of their clergy. I can’t boast of being a pioneering activist because my lifestyle hardly changed. I thought there was plenty of time for society to adjust to a warmer world. No more!
Al Gore did a wonderful service with An Inconvenient Truth. As atmospheric science hardens, most projections in the 2006 film have been confirmed, except the timescale was not pessimistic enough. Probes to measure gases in polar ice recording the fossil atmosphere and in mud cores of ancient lakes to identify prehistoric tree pollen reveal the climate has occasionally changed abruptly in geological history. Instead of centuries or millennia, it can flip from one equilibrium state to another in a matter of decades. This is a tipping point, like a cliff that looks solid one day but tumbles into the sea the next, treacherous to the unwary stroller who thinks the edge is stable and still some way off, until he steps into air.
