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Using local historical data, the purpose of this paper is to compile a chronology of high‐magnitude snow avalanches to illustrate the effectiveness of information published in newspapers in assisting the management of natural hazards.

Major transportation lines parallel the southern boundary of Glacier National Park, Montana, USA, an area where snow avalanches occur frequently and occasionally block transportation corridors. A 1986 study presented an avalanche chronology for the study area based on information collected from the 1946 to 1982 issues of a local weekly newspaper. We extend that existing data set here by using the same newspaper, recording avalanche occurrences and impacts reported in the newspaper from 1982 to 2005.

The newly updated chronology is presented, with trends and temporal patterns for the entire 1946‐2005 data set analyzed. A decrease in reported avalanches, from the 1960s onward, is noted. Additionally, reported avalanches shifted from occurring most frequently in February to January in the last 20 years.

The results of this research illustrate the use of newspaper reports as an inexpensive, but effective, way to compile a chronology of high‐magnitude snow avalanches. This research method tends to underreport smaller magnitude events that do not affect the transportation linkages.

Snow avalanche managers could use this method to compile a chronology of events when other, more traditional techniques, are not available or too expensive.

This paper uses a rarely utilized but inexpensive and widely available data source to construct a 59‐year avalanche chronology in an area constantly threatened by snow avalanches.

This paper presents adaptations and tests undertaken to allow an information retrieval (IR) system to forecast the likelihood of avalanches on a particular day. The forecasting process uses historical data of the weather and avalanche conditions for a large number of days. A method for adapting these data into a form usable by a text‐based IR system is first described, followed by tests showing the resulting system’s accuracy to be equal to existing ‘custom built’ forecasting systems. From this, it is concluded that the adaptation methodology is effective at allowing such data to be used in a text‐based IR system. A number of advantages in using an IR system for avalanche forecasting are also presented.

During the analysis of the 1999 avalanche winter and of the winter storm Lothar on 26 December 1999, the Swiss Federal Institute for Snow and Avalanche Research SLF, Davos conducted an inquiry of the cable car‐ and ski lift‐companies in German‐ and French speaking part of Switzerland. This arti‐cle presents the results in detail. In the whole of Switzerland there were 1'821 cable cars and ski lifts in 1999 (not counting 550 small ski lifts). The SLF sent its questionnaire to 117 companies. A considerable proportion of them (79%) have been returned. In February 1999 avalanches and snow pressure induced damages on 44 cable cars and ski lifts; repairs cost more than 17 Mio. SFr. Due to high avalanche danger, 37% of all lift facilities had to be closed for an average of seven days. The loss of earnings for Switzerland (without Ticino) is estimated at 78 Mio. SFr. compared to February 1998. The winter storm Lothar caused damage to 127 cable cars and ski lifts. The cost of damage repairs is estimated at 7.6 Mio. SFr. The storm interrupted power supply for 14% of the lift facilities; 58% had to be closed down due to high wind speeds. The loss of earnings caused by winter storm Lothar amounts to approx. 39 Mio. SFr. for the Swiss cable car and ski lift companies (without Ticino). Immediately after the events of 1999, 32% of the companies interviewed took measures to reduce the negative consequences (e.g. price reductions, press releases or publicity campaigns). To improve public relations is considered to be an important measure to cope with consequences of natural hazards in the future by 39% of the companies.

An extension of the Scharfetter‐Gummel discretization scheme is presented which is designed for electrothermal semiconductor device equations including avalanche generation terms. The scheme makes explicit use of the exponential character of solutions, and reduces to the standard Scharfetter‐Gummel scheme in the isothermal non‐avalanche case.

Time and frequency domain complementary numerical models of microwave non‐linear circuits using two‐terminal active semiconductor devices are presented. Their main feature is the use of numerical one‐dimensional macroscopic physical models as semiconductor device models. Their respective capability is illustrated by some results of a study devoted to the optimization of millimeter‐wave avalanche diode frequency multipliers.