Monday February 08, 2010 
RESEARCH - INFRASONIC DETECTION OF AVALANCHES |
|
Inter-Mountain Laboratories, Inc. located in Sheridan, Wyoming has been performing investigative avalanche-generated infrasound research projects that began in 2000 and are funded through 2008. This research has been a collaborative effort involving personnel from many entities that include:
A summary of the project history follows. Links to publications generated from this research are included. Pre 2000/01Sub-audible low frequency sound waves in the infrasonic spectrum are generated by many natural and manmade sources including earthquakes, the northern lights, volcanic eruptions, hurricanes, ocean waves and some animals including elephants. In the 1950’s infrasonic sensing technology was developed to monitor nuclear explosions. Research in the late 1980’s and 1990’s by scientists at the National Oceanic and Atmospheric Administration (NOAA) in Boulder Colorado led to the belief that avalanches emit a unique infrasonic sound signature that that could lead to the development of an automated avalanche detection system. 2000/01 & 2001/02In September 2000, NOAA scientist awarded the air science section of Inter-Mountain Laboratories Inc. a six-month Small Business Innovative Research Grant to conduct research for the purposes of developing a single sensor infrasonic avalanche detection system. In January 2001, an infrasound sensor detected the signal emanating from an avalanche that was explosively triggered at the Revolving Door slide path located 1,000 meters from the lower Alpine Lift Shack at the Bridger Bowl Ski Area near Bozeman, Montana. This event provided justification for this Small Business Innovative Research Grant program to extend this research for an additional two years. During the 2001/02 winter-field season single sensor systems were deployed at the Alta Ski Resort and in Provo Canyon in Utah, at the Bridger Bowl Ski Area in Montana, at Thompson Pass in Alaska, at Red Mountain Pass in Colorado and at the Jackson Hole Mountain Resort in Wyoming. These efforts enabled the research team to characterize the infrasonic avalanche signal, develop a single sensor avalanche identification algorithm and obtain data necessary to design sensors specifically for the detection of avalanches. The results of efforts through the winter 2001/2002 season were published in the proceedings of the 2002 International Snow Science Workshop. INFRASONIC MONITORING OF AVALANCHE ACTIVITY2002/03During the 2002/03 winter-season single sensor systems were deployed at two locations at Alta, at two locations at the Jackson Hole Mountain Resort and along Wyoming Highway 22 near the Glory Bowl Slide Path on Teton Pass. Twenty-four documented infrasound signals generated from both natural and explosive triggered avalanches were recorded. This research determined single sensor systems were capable of detecting avalanches, however the ability to detect small avalanches during periods of high wind noise was limited. Results from distributed single sensor systems deployed at Alta and the Jackson Hole Mountain Resort indicated that multiple sensors would likely mitigate the effects of wind noise. These efforts concluded the NOAA funded research. A poster board of pertinent project results through the winter 2002/2003 season was presented during the special infrasound session U03 of American Geophysical Union Fall 2003 meeting. U31B-008 Avalanche-Generated Infrasound Signals2003/04The results of the NOAA funded research enabled Inter-Mountain Laboratories Inc., to obtain a National Science Foundation Small Business Innovation Research grant to investigate using multiple sensors to mitigate the impacts of wind noise and characterize avalanche magnitude and signal origination locations. Concurrently a Wyoming Department of Transportation grant was awarded to research the feasibility of using this technology in a highway avalanche hazard mitigation program. During the 2003/04 winter season an array of multiple sensors were deployed in the Tensleep Bowl area of the Jackson Hole Mountain Resort. Distributed single sensor monitoring systems were also concurrently operated in the Tensleep Bowl, Cirque and Mid-Mountain areas of the resort and near the Glory Bowl and Twin Slides avalanche paths on Teton Pass. These efforts found that multiple sensors greatly increased the ability of infrasound monitoring to mitigate the masking of avalanche signals by wind and interfering signal sources. Multiple sensor array technology was also found to have the capability to determine the location and magnitude of avalanches. Summaries and results of research progress through the 2002/2003 winter season were published in the proceedings of the 2004 International Snow Science Workshop. RECENT STUDIES USING INFRASOUND SENSORS TO REMOTELY MONITOR AVALANCHE ACTIVITYRESULTS OF RECENT INFRASONIC AVALANCHE MONITORING STUDIESAlso, extended summaries and results of research progress through the 2002/2003 winter season have been accepted for publication in the special International Snow Science Workshop 2004 edition of the Cold Regions Science and Technology journal. SINGLE AND MULTIPLE SENSOR IDENTIFICATION OF AVALANCHE GENERATED INFRASOUND2004/05Multiple newly designed sensors were deployed in distributed arrays at the Tensleep Bowl, Twin Slides and Glory Bowl slide paths during the 2004/05 winter-season. To test the effectiveness of these new sensors and gain additional knowledge, arrays of the older sensors were operated in conjunction with the new sensor arrays. The data obtained greatly increased the knowledge and understanding of the ability of this technology to be used as an effective avalanche monitoring system. Innovative data processing techniques were used to monitor avalanche events as they occurred and provide detailed information regarding avalanche event location and size. Data processing techniques were improved and a proto-type for a near-real time monitoring system was developed. 2005/06During the 2005/06 winter-season prototype avalanche monitoring systems were operational in Tensleep Bowl at the Jackson Hole Mountain Resort and along the Twin Slides and Glory Bowl avalanche paths on Teton Pass. The systems on Teton Pass provided near-real time information regarding avalanche activity to the Wyoming Department of Transportation avalanche specialists responsible for the highway avalanche mitigation program. This system was useful in detecting artificially triggered and spontaneously released avalanches while these managers were in the critical decision making process. Due to its reliability it became a valuable component of their mitigation program during several storm cycles. The results of efforts through the winter 2005/2006 season were submitted for publication in the proceedings of the 2006 International Snow Science Workshop. PRACTICAL IMPLEMENTATION OF AVALANCHE INFRASOUND MONITORING TECHNOLOGY FOR OPERATIONAL UTILIZATION NEAR TETON PASS WYOMINGAlso, additional results will be submitted for publication in the special International Snow Science Workshop 2006 edition of the Cold Regions Science and Technology journal. 2006/07Based on project success, permanent installations are under construction (fall 2006) on the Twin Slides and Glory Bowl slide paths on Teton Pass and a new temporary installation in Little Cottonwood Canyon in Utah (Utah Department of Transportation) is expected to be operational during 2006/07. For further information please contact Inter-Mountain Laboratories, Inc. Funding of the aforementioned research was provided via:
|
|