Tag Archives: Snow

Avalanche! How Trees Hold the Secrets of the Past…

Jen Dickie

Stob Ghabhar, Scotland. This image was taken from the Geograph project collection. See this photograph's page on the Geograph website for the photographer's contact details. The copyright on this image is owned by Richard Webb and is licensed for reuse under the Creative Commons Attribution-ShareAlike 2.0 license. Last month, tragedy struck in the Scottish Highlands when an avalanche swept four climbers to their deaths. The experienced mountaineers were descending the Bidean Nam Bian peak on the southern side of Glencoe when the avalanche hit, causing them to fall 1000ft (c. 300m) before being buried under dense snow.  In a report for The Independent, Richard Osley describes how the tragedy occurred shortly after the Scottish Avalanche Information Service (SAIS) issued a warning that human-triggered avalanches were likely in the Glencoe area and the risk was rated as ‘considerable’.  The SAIS reported that on the day of the avalanche, there did not appear to be much depth of snow on the hills of Glencoe, however, there were areas of “mainly hard, unstable windslab” that overlay “a persistent softer weaker layer”; in these conditions more compact blocks of snow can separate from the surrounding snow resulting in a ‘Slab Avalanche’, this type of avalanche is responsible for the majority of avalanche-related fatalities.

As the popularity of the winter sports industry grows, there is increasing pressure on scientists to predict where and when avalanche events will occur.  Dedicated research centres such as the Swiss Institute for Snow and Avalanche Research are continually improving our understanding of avalanche formation and dynamics and therefore providing increasingly reliable warning services, however, they highlight that we are still unable to accurately predict “why, when and where an avalanche will be released”.

In an article for Area, Mircea Voiculescu and Alexandru Onaca describe how they have applied dendrogeomorphological methods to assess snow avalanches in the Sinaia ski region in the Romanian Carpathian Mountains.  By combining climatological and nivological (physical properties of the snow) analyses with information on disturbances recorded in tree growth, they argue that historical avalanche activity can be reconstructed, including the frequency, magnitude and return-period characteristics of the events.  This knowledge, they argue, can be used to make assessments of risk in areas such as the Carpathian Mountains, where the geomorphological understanding of local avalanches is limited.

As winter sports become more popular with non-expert communities, there is growing pressure to identify high risk areas and to provide appropriate warning systems that non-experts can understand.  It is clear that real-time observations and local knowledge are key to identifying avalanche risk, however, this research shows that by combining different techniques and approaches, we can increase our knowledge and understanding of hazards such as avalanches, and provide essential risk information to previously unmonitored regions such as newly established winter sports resorts.

books_icon Mircea Voiculescu and Alexandru Onaca, 2013, Snow avalanche assessment in the Sinaia ski area (Bucegi Mountains, Southern Carpathians) using the dendrogeomorphology method, Area 45 109–122 doi: 10.1111/area.12003

60-world2 Four climbers die in Glencoe avalanche, The Independent, 20th January 2013

60-world2 SportScotland Avalanche Information Service, accessed on 18th January 2013

60-world2 The WSL Institute for Snow and Avalanche Research SLF, accessed on the 18th January 2013

Skiing and snow: a novel proxy for better science communication

By Daniel Schillereff

The first snowfall on the peaks of Snowdonia could be observed from my University building today, I have received the first ‘snow dump alerts’ for a number of alpine ski resorts (see Webcam link below) and televised ski competitions have kicked off for the 2012/13 season. These events inspire personal feelings of elation and excitement every year associated with snow and skiing. Imagine my delight when I discovered the keywords ‘ski’ and ‘geomorphology’ attributed to the same paper this week! These are applied to an Early View paper in Area by Voiculescu and Onaca examining the frequency and magnitude of snow avalanche risk over recent decades at the Sinaia ski resort, Romania, using dendrogeomorphological techniques.

Their approach employs high-precision visual examinations of tree rings in order to identify damage delivered by severe avalanches. The annual growth rings enable the specific year in which each avalanche occurred to be confirmed. They subsequently apply frequency statistics to these data to estimate return periods for the most hazardous snow avalanches. Using such historical data to improve avalanche risk estimation will be invaluable for developing mitigation strategies and preventing future disasters, considering the fatalities which occur due to avalanches each year.

There would be considerable value for this post to examine the techniques they use in greater detail, but I think there are more widespread implications also, of which this is one example.  Many scientific blogs feature practising academics or other experts offering explanations of recent peer-reviewed research using terminology more accessible to any reader and a better understanding of complex analytical techniques by the public has widespread implications. A great number of people poorly understand science presented on such crucial topics as climate change and extreme events, for example, and this can be the result of either insufficient explanation or, more concerning, intentional misinterpretation.

The Leveson report, released on Thursday November 29th, 2012 and featured prominently in the recent news, repeatedly highlights false balance in media reporting on GM crops and climate change, for example. Blogs, by definition, are an avenue for personal opinion to be put forward; nevertheless, they offer opportunities for the public to easily access expert knowledge on highly relevant topics. As a result, provided science blogs ensure the professional qualifications and experience of contributors can be easily verified by readers, blogs will become an increasingly important method for effective communication of complex science relevant to the public.

  M Voiculesco, A Onaca, 2012, Snow avalanche assessment in the Sinaia ski area (Bucegi Mountains, Southern Carpacians) using the dendrogeomorphology method, Area DOI: 10.1111/area.12003.

 Real-time Val d’Isere Webcam: http://www.val.co.uk/webcam.htm

 Leveson report: ‘I cannot recommend another last chance saloon for the press’,  The Guardian, 29 November 2012

 Leveson Inquiry: Culture, Practice and Ethics of the Press report available here: http://www.levesoninquiry.org.uk/about/the-report/

Spreading salt on the right roads?

by Jayne Glass

The news in late 2010 has been all about ‘the big freeze’.  Heavy snow has been falling across the UK earlier than normal, with some devastating effects. Usually, local councils work to keep the roads and pavements clear by spreading salt/grit. But despite attempts to stockpile salt ahead of this winter, some councils are already running low.  In Powys, Carmarthenshire and Caerphilly, councils have already used at least a quarter of their stock, and across Wales 15% of the salt supply has gone.

In 2008, John Thornes and Lee Chapman focussed on decision-making for salt spreading, in an article in Geography Compass.  Although the use of weather information systems for the winter maintenance of roads is now widespread, observations and predictions are often only available for a limited number of road sensor sites in a region.  Thornes and Chapman carried out a winter-long trial of the XRWIS road weather information system in Devon.  They found that up to 78 salting runs on 6 salting routes could have been prevented.  This would have saved up to £80,000 in labour and materials.  There is also scope for this system to be applied to prediction of low rail adhesion on the national rail network.

‘Road salt is disappearing fast, Welsh councils warn’: BBC News, 2 December 2010

Thornes, J. and Chapman, L. (2008). The Next Generation Road Weather Information System: A New Paradigm for Road and Rail Severe Weather Prediction in the UK. Geography Compass, June 2008

Ice loss on Mount Everest

By Richard Gravelle

Several weeks ago, I wrote that Nepalese Sherpas have claimed that the effects of climate change are making Mount Everest more dangerous and difficult to climb (Is climate change making Everest more dangerous? June 5, 2010).  It is generally accepted that Everest, like other mountains worldwide, is undergoing increased rates of ice and snow melt.  However, a recent attempt by the Asian Society (AS) to take photographs of Everest from the same spot as George Mallory did in 1921 suggest that the problem may be worse than previously thought.

Comparison of the photographs revels that the main glacier on Everest, the Rongbuk glacier, has undergone a significant loss of ice mass in the last 89 years, a trend which is unfortunately unlikely to be reversed under present conditions.

Photographer David Breashears is quoted as saying “If this isn’t evidence of the glaciers in serious decline, I don’t know what is”.  These photographs act as a stark reminder of the effects of climate change, as well as allowing us to see exactly how environmental changes have occurred over the past century.

BBC News – Comparative photos of Mount Everest ‘confirm ice loss’.  16th Jul 2010