Engineers model the threat of avalanches

Jul 25, 2012 By Anne Ju

(Phys.org) -- Snow avalanches, a real threat in countries from Switzerland to Afghanistan, are fundamentally a physics problem: What are the physical laws that govern how they start, grow and move, and can theoretical modeling help predict them?

Cornell researchers have uncovered some clues. Graduate student Cian Carroll was lead author on a paper published in the journal in June that details a for the acceleration and growth of what the researchers call the avalanching "cloud." They hope their model can predict avalanche size, speed, density and other parameters to help in planning in high-risk areas, Carroll said.

Prior research on snow avalanches shows that a significant amount of mass is picked up at the "head" of a gravity current. The mass distributes into the rest of the current, or cloud, and this mass travels at the front of the cloud as it densifies, accelerates and grows -- leading to .

The researchers first looked at the mechanism responsible for the rapid pickup of snow that occurs within the first few meters of the current. They determined that a mechanism driven by pressure gradients penetrating within the snow pack destabilized and broke apart the snow particles.

They then looked at the area just above the snow pack to see the effect the snow pickup had on the overlying cloud and its associated . They observed that varying densities changed how the internal velocity took shape in the cloud, which they checked with experiments performed in a water flume. Further simulations allowed them to look into greater details of the effects that viscosity has on current and how this changes the cloud's swelling.

The paper was co-authored by Michel Louge, professor of mechanical and , and Carroll's adviser; as well as Barbara Turnbull of the University of Nottingham.

The research was supported by the Petroleum Research Fund.

Explore further: Precision gas sensor could fit on a chip

Related Stories

Punching holes in the sky

Jul 12, 2011

Scientists, photographers and amateur cloud watchers have been looking up with wonderment and puzzlement at "hole punch" clouds for decades. Giant, open spaces appear in otherwise continuous cloud cover, presenting ...

Avalanches -- triggered from the valley

Dec 02, 2008

Everybody knows that skiers swishing down steep slopes can cause extensive slab avalanches. But there is a less well known phenomenon: A person skiing a gentle slope in the valley triggers a slab avalanche ...

Thin Colorado snowpack reported again

May 22, 2006

Another warm and dry spring in Colorado has resulted in a thin snow pack possibly increasing risk of wildfires and parched farm fields, a report said.

New way to measure sulfate particles

Oct 07, 2005

The University of Maryland and the National Institute of Standards and Technology created an improved technique to measure sulfur isotopic ratios.

Snow hits Bosnian capital

May 14, 2012

The Bosnian capital and its surroundings were covered by snow on Monday, the first time in half a century snow has settled in Sarajevo at this time of year, as temperatures plunged to just above freezing.

Recommended for you

New filter could advance terahertz data transmission

6 hours ago

University of Utah engineers have discovered a new approach for designing filters capable of separating different frequencies in the terahertz spectrum, the next generation of communications bandwidth that ...

The super-resolution revolution

6 hours ago

Cambridge scientists are part of a resolution revolution. Building powerful instruments that shatter the physical limits of optical microscopy, they are beginning to watch molecular processes as they happen, ...

Precision gas sensor could fit on a chip

8 hours ago

Using their expertise in silicon optics, Cornell engineers have miniaturized a light source in the elusive mid-infrared (mid-IR) spectrum, effectively squeezing the capabilities of a large, tabletop laser onto a 1-millimeter ...

A new X-ray microscope for nanoscale imaging

9 hours ago

Delivering the capability to image nanostructures and chemical reactions down to nanometer resolution requires a new class of x-ray microscope that can perform precision microscopy experiments using ultra-bright ...

New research signals big future for quantum radar

21 hours ago

A prototype quantum radar that has the potential to detect objects which are invisible to conventional systems has been developed by an international research team led by a quantum information scientist at the University ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.