Evidence of accelerated englacial warming in the Monte Rosa area, Switzerland/Italy

A range of englacial temperature measurements was acquired in the Monte Rosa area at the border of Switzerland and Italy in the years 1982, 1991, 1994, 1995, 1999, 2000, 2003, 2007 and 2008. Englacial temperatures revealed no evidence of warming at the firn saddle of Colle Gnifetti at 4452 m a.s.l. between 1982 and 1991, the 1991 to 2000 period showed an increase of 0.05 °C per year at a depth of 20 m. From 2000 to 2008 a further increase of 1.3 °C or 0.16 °C per year was observed, indicating that the amount of infiltrating and refreezing meltwater at Colle Gnifetti has probably increased since 2000. The measured temperatures give clear evidence of firn warming since 1991. This is confirmed by five existing boreholes with measured temperature down to bedrock, which were drilled in 1982, 1995, 2003 and 2005. All the observed temperature profiles show a slight bending to warmer temperatures in their uppermost part indicating a warming of the firn, which can be related to the observed atmospheric warming in the 20th century. However, the drilling sites on Colle Gnifetti are still located in the recrystallisation-infiltration zone

Evidence of accelerated englacial warming in the Monte Rosa area, Switzerland/Italy

A range of englacial temperature measurements was acquired in the Monte Rosa area at the border of Switzerland and Italy in the years 1982, 1991, 1994, 1995, 1999, 2000, 2003, 2007 and 2008. Englacial temperatures revealed no evidence of warming at the firn saddle of Colle Gnifetti at 4452 m a.s.l. between 1982 and 1991, the 1991 to 2000 period showed an increase of 0.05 °C per year at a depth of 20 m. From 2000 to 2008 a further increase of 1.3 °C or 0.16 °C per year was observed, indicating that the amount of infiltrating and refreezing meltwater at Colle Gnifetti has probably increased since 2000. The measured temperatures give clear evidence of firn warming since 1991. This is confirmed by five existing boreholes with measured temperature down to bedrock, which were drilled in 1982, 1995, 2003 and 2005. All the observed temperature profiles show a slight bending to warmer temperatures in their uppermost part indicating a warming of the firn, which can be related to the observed atmospheric warming in the 20th century. However, the drilling sites on Colle Gnifetti are still located in the recrystallisation-infiltration zone. <br><br> A much stronger warming of 6.8 °C or 0.4 °C per year was found at locations beneath Colle Gnifetti on Grenzgletscher from 1991 to 2008. This warming is one order of magnitude greater than the atmospheric warming and can be explained only by a strong increase in the latent heat input by infiltrating and refreezing meltwater. The observations indicate that since 1991, an important firn area beneath Colle Gnifetti has already undergone a firn facies change from the recrystallisation-infiltration to the cold infiltration zone due to an increasing supply of surface melt energy

Avalanche fatalities in the European Alps: long-term trends and statistics

Avalanche accidents, particularly those resulting in fatalities, attract substantial attention from policy makers and organizations, as well as from the media and the public. Placing fatal accidents in a wider context requires long-term and robust statistics. However, avalanche accident statistics, like most other accident statistics, often rely on relatively small sample sizes, with single multi-fatality events and random effects having a potentially large influence on summary and trend statistics. Additionally, trend interpretation is challenging because statistics are generally explored at a national level, and studies vary in both the period covered and the methods. Here, we addressed these issues by combining the avalanche fatality data from the European Alps (Austria, France, Germany, Liechtenstein, Italy, Slovenia, and Switzerland) for three different periods between 1937 and 2015 and applying the same data analysis methodology. During the last four decades, about 100 people lost their lives each year in the Alps. Despite considerable inter-annual variation, this number has remained relatively constant in the last decades. However, exploring fatality numbers by the location of the victims at the time of the avalanche revealed two partly opposing trends. The number of fatalities in controlled terrain (settlements and transportation corridors) has decreased significantly since the 1970s. In contrast to this development, the number of fatalities in uncontrolled terrain (mostly recreational accidents) almost doubled between the 1960s and 1980s and has remained relatively stable since then, despite a strong increase in the number of winter backcountry recreationists. Corresponding to these trends, the proportion of fatalities in uncontrolled terrain increased from 72 to 97 %. These long-term trends were evident in most national statistics. Further, the temporal correlation between subsets of the Alpine fatality data, and between some of the national statistics, suggests that time series covering a longer period may be used as an indicator for missing years in shorter-duration datasets. Finally, statistics from countries with very few incidents should be compared to, or analysed together with, those from neighbouring countries exhibiting similar economical and structural developments and characteristics

Integrated Real-Time Vision-Based Preceding Vehicle Detection in Urban Roads

7th International Conference on Intelligent Computing, ICIC 2011, Zhengzhou, 11-14 August 2011This paper presents a real-time algorithm for a vision-based preceding vehicle detection system. The algorithm contains two main components: vehicle detection with various vehicle features, and vehicle detection verification with dynamic tracking. Vehicle detection is achieved using vehicle shadow features to define a region of interest (ROI). After utilizing methods such as histogram equalization, ROI entropy and mean of edge image, the exact vehicle rear box is determined. In the vehicle tracking process, the predicted box is verified and updated. Test results demonstrate that the new system possesses good detection accuracy and can be implemented in real-time operation.Department of Civil and Environmental Engineerin