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Photo: Kim Willsher/The Guardian.
Pralognan-la-Vanoise in the French Alps is in danger from global warming. An engineering operation to prevent catastrophic flooding will cost about €400,000 ($465,000). 

As discouraging as it is to read another story about global warming, one has to feel a little hopeful that human ingenuity keeps tackling its effects.

Kim Willsher reports at the Guardian about how engineering is fighting back in France. I leave it to you to decide whether putting humans first or the glacier first would be best.

The villagers of Pralognan-la-Vanoise in the French Alps know well the perils posed by the mountains that encircle them. Avalanches, rockfalls, mudslides, sudden crevices and torrents of water are within the living memory of most villagers, and every day the climate emergency throws up new dangers.

“Less than a year ago, an enormous lake formed by a melting glacier was discovered high above Pralognan that experts feared could inundate the village with more than 60,000 cubic metres [15,850,000+ gallons] of icy water. …

“As used to natural hazards as local people are high up in the Alps, they are not, however, an idle threat. The Swiss village of Blatten was wiped out by a rock and ice avalanche in May and last year a mountain lake swollen by heavy rainfall caused torrential flooding in La Bérarde in the Isère, forcing inhabitants to flee the hamlet. They have not returned.

“Today, an engineering operation is under way to prevent such a catastrophic scenario in Pralognan. Three workers have been helicoptered to the Grand Marchet glacier at an altitude of 2,900 metres [1.8 miles] to gouge a [narrow] ‘overflow channel’ in the ice. …

“ ‘The aim is to help the water find its way down the mountain gradually and avoid a rapid emptying of the lake,’ said David Binet, the director of the mountain land restoration service (RTM) for the northern Alps, part of the national forestry commission tasked with identifying and preventing natural hazards.

“ ‘What causes the problems and damage with torrents in the mountains is not the water but the stones, gravel, sand and even large rocks it brings down with it.’

“The glacier blocks the lake from spilling down the mountain but it is shrinking at a rate of 2 to 3 metres [6.6 to 9.8 feet] a year. There is also the risk that that the warmer waters of the lake could form a channel gush from underneath.

“Binet said his agency was examining 300 of the estimated 600 lakes in the Alps and Pyrenees one by one for such hazards. The Pralognan operation will cost about €400,000 [$465,000)]. …

“The idea of taking mechanical shovels to glaciers already shrinking at an alarming rate was deemed the least environmentally damaging option. Olivier Gagliardini, a glacier expert at Grenoble University, described it as ‘unfortunate, but necessary.’

“Martine Blanc, the mayor of Pralognan, said … ‘We asked ourselves could it wait but on the principle that prevention is better than cure we decided to go ahead,’ she said. ‘We decided to anticipate events rather than suffer them. Nature is nature and there’s no such thing as zero risk.’ …

“Local shopkeepers say the number of tourists and hikers this summer is down, possibly because the campsite is closed, but Silvere Bonnet, the director of the tourist office, said he had had very few calls from potential visitors concerned about the lake. …

“On a sunny day, the giant rock faces etched with shimmering cascades that rise almost vertically have a benevolent beauty. An hour later in a rapid change of atmosphere, the peaks are cloaked in dark clouds and loom intimidatingly.

“ ‘They can appear rather menacing at first to visitors because they are so sheer,’ [Bernard Vion, a 66-year-old Alpine guide who has watched the expanse of water grow and the mountain change over his lifetime] said. The 66-year-old knows these mountains ‘like his pocket,’ as the French say. He made his first high-altitude climb aged eight with his father, also a guide. Both his grandfathers were Alpinists.

“Vion first spotted what he describes as ‘a puddle’ of water on the Grand Marchet glacier in 2019. Every year since he has watched it grow; it now measures almost 2.5 acres. …

“ ‘We are on the frontline of climate change here. We know it is happening,’ he said.

“Blanc agreed. … ‘People here are used to natural hazards. We’re used to avalanches, falling rocks, torrential floods and mudslides because we’ve seen them and lived with them since we were young. Local people understand there are things we can control and then those we cannot.’ ”

More at the Guardian, here.

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Photo: Bennett Whitnell / Hakai Institute.
Sunflower stars and vase tunicates grow on the sea floor of Rivers Inlet, British Columbia, in 2023.

There have always been voters who care more about knocking a few cents off the gas they put in their SUVs than researching what’s going on with some small creature in the natural world.

But many of us do care about the natural world and believe that a dieoff in any one area can have repercussions for humanity. Everything is connected.

John Ryan reports at OPB (Oregon Public Broadcasting) about how scientists worked to “crack the case” of melting sea stars.

He writes, “Researchers in Washington and British Columbia say they have solved a deadly mystery that has stumped scientists for more than a decade. They have identified the pathogen behind one of the world’s biggest disease outbreaks: a wasting disease that has turned billions of sea stars into goo – from Alaska to California.

“A mass dieoff of ocean-shaking proportions began among sea stars along North America’s West Coast in 2013. Of 20 species affected, the pizza-sized sunflower star was hardest hit. More than 5 billion sunflower stars, or 90% of their global population, wasted away.

“With key predators of sea urchins largely wiped out, the spiny little grazers proliferated and chewed their way through kelp forests, leading to widespread losses of that productive ocean habitat.

“For 12 years, the cause of the wasting disease was either unknown or, mistakenly, thought to be a virus. Instead, the new study says, it is a strain of bacteria known as Vibrio pectenicida. Other Vibrio bacteria sicken corals and shellfish. One species, Vibrio cholera, causes cholera in humans.

“ ‘It is not surprising that it is a Vibrio,’ said biologist Alyssa-Lois Gehman of British Columbia’s Hakai Institute. ‘It was surprising because it took us so long to find out that it was a Vibrio.’

“Gehman and her coauthors are not the first scientists to claim to have found the culprit behind the worst underwater wildlife pandemic on record. …

“Gehman said the new study, published in the journal Nature Ecology & Evolution, avoids a key oversight of the earlier work by focusing on the sea stars’ blood-like internal fluid and not just its external tissues, where many other microbes live. …

“Gehman’s research team not only found much more Vibrio pectenicida in sick stars than in healthy ones. They were able to isolate the Vibrio, grow it in the lab, and give the wasting disease to healthy sunflower stars by injecting them with the Vibrio, steps the earlier researchers had not achieved. …

“The current study grew out of four summers of experiments at the U.S. Geological Survey’s Marrowstone Marine Field Station, a beachfront facility on Marrowstone Island, near Port Townsend, Washington. Avoiding microbial contamination was a top priority.

“ ‘There’s a lot of ethanol and bleach and betadine,’ Gehman said. …

“Researchers stepped in foot baths when entering and leaving the facility. Each sunflower star, after enduring a two-week quarantine, lived in its own tank with its own supply of sand-filtered, ultraviolet-treated seawater. Researchers avoided touching the stars, even with gloves on.

“In January 2024, after analyzing the previous summer’s data, the researchers found large amounts of Vibrio pectenicida in sick sunflower stars and hardly any in healthy stars. …

“Sunflower stars have become so rare that taking any from the wild is both difficult and potentially harmful to the species.

“ ‘We ran at sort of the bare minimum necessary to get robust and strong evidence,’ Gehman said.”

Continued research is under threat. The administration in DC proposes to cut the key U.S. Geological Survey budget 38% in 2026 and eliminate its biological research arm, which environmental advocates call “the backbone of environmental and ecological monitoring.”

More at OPB, here.

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