Echoes of old walls appear, briefly, in Britain’s arid soil during the baking heat

Parch marks at Mottisfont in Hampshire, England, during this northern summer. They show remnants of buried wall foundations. The dry hot weather makes them clear when they normally wouldn't be. Photo / National Trust

On a grassy expanse at the largest monastic ruins in Britain, a dry scar emerged just days ago in the earth.

And at a historic home and ancient priory more than 320km to the southwest, patches of brown became visible through grass, as if the ground was trying to recall a half-forgotten memory.

But these patches are not paths, past or present.

Instead, the lines recall ancient buildings, whose old foundations form these “parch marks”, which emerge in dry periods when the grass growing over buried ruins dries at a different rate than in other areas.

“It’s almost like a photograph within the landscape itself,” said Chris Gosden, an emeritus professor of European archaeology at the University of Oxford.

These parch marks, which lace across grass like veins on a forearm, have appeared in two British historical sites in recent days, the National Trust, which manages the sites, said today.

They appeared after Britain endured one of its driest springs on record, and are a sign of how the climate crisis is affecting the region.

The frequency with which the parch marks are visible has “noticeably increased” in recent years, as “climate change increases the likelihood of hotter, drier weather in spring and summer,” Tom Dommett, the National Trust’s head of historic environment, said in a statement.

The marks are one sign of how climate change is radically affecting the landscape around the world and, in some cases, revealing hidden history.

Melting glaciers in Peru and Nepal have revealed the lost bodies of mountain climbers.

Floods in Egypt are corroding the stones of ancient temples.

And droughts in Spain, Italy and elsewhere in Europe have brought flooded villages and old ruins back, briefly, into the sunshine.

But even as changing weather forces the land to cough up secrets, the climate crisis is also threatening the past that the dirt has protected for generations.

“Overall, climate change is a bad thing for archaeology — even though it may have temporary benefits,” said Gosden, who partly attributed the increasing visibility of parch marks to the availability of drones.

“There are things revealed, but the cost to the archaeological evidence, overall, is really considerable.”

The marks are useful for archaeologists, even though they reveal the potential dangers to the sites that climate change could continue to bring.

The parch marks at Mottisfont, a historic home and ancient priory in southwestern England, revealed the presence of monastery buildings.

Those at Fountains Abbey, which was founded in 1132 by Benedictine monks, showed the outlines of a guest hall.

“It is an exciting and positive aspect to something that’s got some quite worrying undertones,” said Mark Newman, an archaeologist at the National Trust, who advises on the abbey in North Yorkshire.

At Fountains, the marks were last visible in 2019, he said, and appeared a few other times since 2010. Before that, he said, they emerged in the late 1990s and 1989, but only rarely.

And the accelerating frequency of their visibility worries him. That’s because climate change can bring periods of extreme heat and also extreme flooding or rains, which can change the actual structure of the soil and cause ruins to shift.

“Should we be horrified? Should we be elated?” he asked, referring to the increasing frequency. “Probably the answer is a mixture of the two.”

The marks show part of a building that was removed in the 1770s. They also show what experts believe was a large guest hall divided into aisles by columns, the National Trust said.

Newman said the guest hall complicates the idea of monks living a secluded, cloistered life.

He noted that the monastery would have “needed accommodation on that sort of scale”, possibly for hundreds of people at a time.

The Unesco world heritage site offers insights into similar communities in Britain, especially because the rapid, bloody rise of Protestantism in the 1500s forced British Catholics underground for generations, Newman said.

Newman said the climate crisis is forcing some archaeologists to reassess a deep belief that old things are safest when left in the ground.

“If you can no longer be certain that the archaeology is safe, then you need to start thinking about that again,” he said, “and whether you’re better digging it now before you lose it.”

This article originally appeared in The New York Times.

Written by: Amelia Nierenberg

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