#avalanches

[cyallowitz]

The Slide-Rock Bolter

Slide-Rock Bolter That thing definitely looks scary.  Also, it’s really big and in the open, which makes one wonder how it’s a mystery.  Where did this thing come from? First, let’s go over what it looks like.  Clearly, the Slide-Rock Bolter is huge, especially the head and mouth. Yet, it has tiny eyes.  The tail is split and hooked, which it uses to grip onto the top of a slanted mountain.  Even…

[kynky]

Finally added a few of my favourites to my collection...

[dropsofsciencenews]

Between Refuge and Risk: The Avalanche Paradox for Mountain Ungulates

ESP version ITA version In the changing context of mountain environments, climate change manifests with rapid and significant transformations, profoundly influencing sensitive communities and ecological processes. A crucial element in this landscape is represented by the seasonal conditions of snow, which prove to be determinants for the dynamics of mountain ungulate populations. These variations directly affect vital ecological and physiological aspects, such as the energy costs of locomotion, vulnerability to predation, and the availability and quality of forage, both in summer and winter.

A recent study published in Nature explored how mountain goats, adapted to steep terrains to evade predators, paradoxically find themselves at risk due to the frequent instability of these slopes, which can generate avalanches. The research, conducted in southeastern Alaska on 421 goats monitored for 17 years, highlights that avalanches cause between 23% to 65% of annual deaths, primarily affecting the young and small. These steep areas, chosen to mitigate the risk of predation, turn out to be ecological traps due to their high risk of avalanches. This risk is variable, with peaks during the most unstable months for snow, especially at the beginning of winter and during the spring thaw.

The migratory and wintering strategies of ungulates further influence their exposure to the risk of avalanches. For example, mountain goats in Lynn Canal are extremely migratory, moving to low-altitude forested habitats during the winter, while other populations remain at higher altitudes, exposing themselves more to danger.

Climate change exacerbates this dynamic, modifying the frequency and intensity of avalanches, and consequently, the spatial and temporal distribution of these lethal events. Forecasts indicate an increase in wet avalanches compared to those of dry snow, with a potential increase in avalanche mortality rates.

The persistence of this risk in mountain systems, combined with the anticipated rise in the snowline elevation, may reduce the avalanche danger at lower altitudes, but the risk will continue to be a significant component in the ecology of mountain ungulates. However, the demographic influence of avalanches on ungulate populations is likely to persist in the future because both the avalanche danger and the ranges of mountain ungulates are expected to shift upward as the climate warms.

It is essential to emphasize that the growth rates of mountain goat populations are particularly low and can only sustain limited annual removals. Therefore, avalanche mortality, especially among young individuals, can have severe demographic impacts, leading to population decline. These data highlight the need to reconsider conservation and management strategies for these vulnerable populations.

The intensification of climate change and its extreme manifestations, such as avalanches, necessitates a rethinking of conservation policies to protect not only mountain ungulates but also the ecological integrity of mountain environments, which are crucial for global biodiversity.

Source: https://www.nature.com/articles/s42003-024-06073-0

Credits picture: NPS/Diane Renkin

[johniac]

SciTech Chronicles. . . . .. .May 22nd, 2025

[rightnewshindi]

हिमाचल में भारी बारिश के कारण दो जगह फटे बादल, पांच हिमखंड गिरे; पंजाब के पर्यटक की हुई मौत, दो अन्य लापता

Himachal Weather: हिमाचल में मौसम विभाग के ऑरेंज अलर्ट के बीच शुक्रवार को कुल्लू के पाहनाला और कांगड़ा के छोटा भंगाल के मुल्थान में बादल फटे। भारी बारिश-बर्फबारी के चलते पंजाब के पर्यटक की मौत हो गई है, जबकि दो लोग लापता और तीन घायल हैं। पिछले 48 घंटों से बारिश-बर्फबारी के कारण जनजीवन अस्त-व्यस्त हो गया है। भूस्खलन-बाढ़ से अलग-अलग जगह 22 वाहन क्षतिग्रस्त हो गए हैं। चंबा, लाहौल और किन्नौर में…

[radioshiga]

Neve no japão diminui, mas alerta permanece

Tóquio, Japão, 25 de fevereiro de 2025 – Kyodo News – A Agência Meteorológica do Japão informa que a forte nevasca no país já passou do seu pico. No entanto, as autoridades alertam para o risco de avalanches e acidentes causados pelo derretimento da neve, já que a previsão é de clima quente. A agência prevê que nesta terça-feira (25), as temperaturas devem retornar ou exceder a média da estação,…

[johnschooler]

Avalanche Mitigation Strategies

Avalanches, which occur from instability in large masses of snow, are strong enough to carry boulders, trees, and buildings. Various factors trigger avalanches, including heavy snowfall, strong wind, earthquakes, loud noises, and some human activity. Avalanches are dangerous threats to property, infrastructure, and human lives...

Read more here

[crabussy]

I'm really curious about this!! in aotearoa, every classroom I was in growing up had posters up on how to respond to an earthquake. "drop, cover, hold" was drilled into me from a very young age. I experienced a few growing up, but they were mild because I don't live in areas where they are more extreme. One of our major cities, christchurch/ōtautahi, gets hit by earthquakes very frequently. if you look at a global seismic hazard map, aotearoa is fully lit up in the colour indicating high hazard chance. wild!!!

for reference, in the UK (similar size country) there are around 20-30 noticeable earthquakes per year. in aotearoa, that number is around 100-250!

[michaelgabrill]

Avalanches Icy Explosions and Dunes: NASA Is Tracking New Year on Mars

Instead of a winter wonderland, the Red Planet’s northern hemisphere goes through an active — even explosive — spring thaw. While New Year’s Eve is around the corner here on Earth, Mars scientists are ahead of the game: The Red Planet completed a trip around the Sun on Nov. 12, 2024, prompting a few researchers […] from NASA https://ift.tt/OcHbvis

[lilywhiteandburgundyandblue]

if you watch sports long enough you start to believe in things like curses

[xtruss]

Researchers studying living pine trees near the Bankso, a ski resort in the Pirin Mountains of Bulgaria, found evidence of dozens of large avalanches that struck the area over two centuries. Credit...Bartek Wrzesniowski/Alamy

Centuries of Avalanches Are Stored in Tree Rings

Discovering Evidence of Deadly Deluges of Snow From the Past Could Help Protect People on Mountains Around the World, Researchers Say.

— By Katherine Kornei | July 10, 2024 | The New York Times

A rumble, a deluge of snow and then silence — avalanches can be deadly, but they often leave behind little enduring evidence of their passage. Now, researchers have turned to tree rings to reconstruct records of avalanches past.

By analyzing the wood of hundreds of living pine trees near a ski resort in Bulgaria, a team of scientists found evidence of dozens of large avalanches that struck the area over two centuries. Understanding the frequency of potentially destructive avalanches can inform risk-management efforts and land-use planning, the researchers suggest. They published their results in the journal Dendrochronologia in June.

The Pirin Mountains in southwestern Bulgaria are home to old-growth forests of pine and fir trees. Many of the trees have been standing for centuries, but some have steeply leaning trunks while others bear conspicuous scars such as broken branches.

“They have certain signs that they were damaged in the past,” said Momchil Panayotov, one of the authors of the study and a dendrochronologist at the University of Forestry in Sofia, Bulgaria.

That damage, many researchers believe, was inflicted by avalanches. The mechanical impact of snow rushing downslope can severely damage a large tree and even uproot it entirely. But visible damage doesn’t reveal when exactly an avalanche occurred, which is important for reconstructing records of the dangerous events. To determine when and where avalanches have occurred in the Pirin Mountains, Dr. Panayotov and Nickolay Tsvetanov, also an author of the study and a dendrochronologist at the University of Forestry, turned to tree rings.

Trees that experience an avalanche develop telltale signs in their rings, Dr. Panayotov said: “The survivors keep the record.”

In 2020 and 2021, Dr. Panayotov, Dr. Tsvetanov and several students collected samples of wood from hundreds of pine trees in the Pirin Mountains that had signs of damage. The team focused on three known avalanche corridors in the Bunderitsa valley, home of the Bansko ski resort. The researchers used an instrument called an increment borer to manually extract pencil-width cores from each living tree. Back in the laboratory, Dr. Tsvetanov dried the cores, mounted them in wooden holders and then sanded them down to reveal individual rings. “It’s a very long process,” he said.

The team then compared those tree-ring records with sequences of rings obtained from nearby undamaged trees. That cross-dating allowed the researchers to pinpoint the timing of unexpected features like suppressed growth, scars and missing rings.

“Trees are amazing recorders of past disturbances, including geomorphic hazards such as snow avalanches,” said Allyson Carroll, a dendrochronologist at California State Polytechnic University, Humboldt, who was not involved in the research.

Dr. Panayotov and Dr. Tsvetanov found evidence of avalanches that took place as far back as the 1600s. But definitively concluding that an avalanche occurred that long ago is challenging, Dr. Panayotov said, as relatively few avalanche-affected trees survive for centuries. The team therefore opted to focus on more recent avalanches.

The researchers inferred that over 20 large avalanches had occurred since the mid-1800s. Some of those events can be linked to historical records — for instance, the avalanche that appears in tree rings dating to 1963 is probably a documented event that occurred on Feb. 12 of that year. But other avalanches seemingly rolled downhill into oblivion. “We don’t have written histories of these events,” Dr. Panayotov said. “We can only rely on tree rings.”

By analyzing the spatial positions of the affected trees, the researchers could also estimate the approximate size of each avalanche. For example, they found that the avalanche that occurred in 1969 was unusually large; it reached high up one of the corridors’ banks. The team also noted that avalanches struck across all three corridors in 1963 and across two corridors in 1931, 1987 and 1996. “There was some specific meteorological situations that favored big avalanches in those years,” Dr. Panayotov said, like strong storms in the wintertime.

But reliably predicting that avalanches are more likely in certain climatic conditions will require more data.

“You need time series that reach farther back in time to get good correlations between climatic conditions and avalanches,” said Markus Stoffel, an environmental scientist at the University of Geneva who was not involved in the research.

Dr. Panayotov and Dr. Tsvetanov hope that their results will contribute to keeping winter-sports enthusiasts safe. Both researchers have a vested interest: Dr. Tsvetanov is a snowboarder, and Dr. Panayotov is a skier who participates in mountain rescue efforts and helps oversee avalanche education and safety at the Bansko ski resort. “I’m a regular over there,” he said.

[johniac]

SciTech Chronicles. . . . . . . . .April 22nd, 2025

[newsdarts]

Avalanches announced historic Nathan Makinan on Monday

Nathan McKinon added to his impressive hockey resume on Monday night, as the Colorado avalanche fights with Dallas stars in game 5 of the Stanley Cup playoff series. The Heart Memorial Trophy winner made things in the second quarter of the competition, assisting an Arturi Lehconan goal, which put Colorado on the board before illuminating the lamp for the second score of the evening to…

[ztremx]

Dreamy Spring Vibes, Happy Solstice and full moon (tomorrow)