Local and Regional Airborne Dust in the Canyonlands Region: Integrated Analysis of Digital Imagery, Total Suspended Particulate, and Meteorological Data Frank E. Urban (1), Richard L. Reynolds (1), Jason C. Neff (2), Daniel P. Fernandez (2), Marith C. Reheis (1), Harland L. Goldstein (1), Edmund E. Grote (3), Chris Landry (4) (1) U.S. Geological Survey, Geology and Environmental Change Science Center, Denver, Colorado (2) Department of Geological Sciences, University of Colorado, Boulder, CO (3) U.S. Geological Survey, Southwest Biological Center, Moab, UT (4) Center for Snow and Avalanche Studies, Silverton, CO Abstract: Improved measurement and observation of dust emission and deposition in the American west would advance understanding of (1) landscape conditions that promote or suppress dust emission, (2) dynamics of dryland and montane ecosystems, (3) premature melting of snow cover that provides critical water supplies, and (4) possible effects of dust on human health. Such understanding can be applied to issues of land management, water-resource management, as well as the safety and well-being of urban and rural inhabitants. The University of Colorado, National Park Service, and USGS have expanded the scope of regional particulate measurement through the establishment of total-suspended-particulate (TSP) measurement stations located in Utah and Colorado with bi-weekly data (filter) collection. A sub-network of high-resolution digital cameras has been co-located with several of the TSP stations, as well as at other strategic locations. These real-time regional dust-event detection cameras are internet-based and collect digital imagery every 6-15 minutes. Measurements of meteorological conditions to support these collections and observations are provided partly by USGS CLIM-MET stations, four of which were deployed in 1998 in the Canyonlands region. These stations provide continuous, near real-time records of the complex interaction of wind, precipitation, vegetation, as well as dust emission and deposition, in different land-use settings. The complementary datasets of dust measurement and observation enable tracking of individual regional dust events. As an example, the first dust-on-snow (DOS) event of water year 2012 (Nov 5, 2011), documented by the Center for Snow and Avalanche Studies at Senator Beck Basin, near Silverton, Colorado, was also recorded by the camera at Island-in-the-Sky, as well as in aeolian activity and wind data from the Dugout Ranch CLIM-MET station. Similar conditions and results were recorded in the most recent DOS event March 6, 2012. At these sites, strong winds and the presence of dense dust preceded increases in relative humidity and associated precipitation. TSP – Particulate Sampler Dust Detection Camera Co-located TSP/Camera CLIM-MET Stations Mojave Desert Colorado Plateau Location Map CLIM-MET site instrumentation: 1. Marble Dust Trap 2. Airfoil Dust Collector 3. Pyranometer 4. Radio Data Telemetry 5. Wind Speed and Direction 6. Air Temperature and Relative Humidity 7. 8. 9. 10. 11. 12. 13. Temperature Gradient Power Module Datalogger Precipitation Gauge BSNE Dust Collector SENSIT Erosion Monitor Soil Moisture Probe (10cm) Environmental data presented here is typically collected at 1 second intervals which are averaged, or totaled to produce an hourly dataset. A full description of instrumentation and procedure, and all archived data is available at http://esp.cr.usgs.gov/info/sw/clim-met/index.html ISKY March 6, 2012 Dust Image Abajo Peak Clear Day Image Abajo Peak March 6, 2012 Dust Image Near real-time and archived data from CLIM-MET stations can be accessed at these websites. 2011 - Dugout Ranch CLIM-MET Average Peak Windspeeds and ISKY TSP Sampler Mean Load 300.000 8 TSP Mean load ug/m3/day - ISKY Average Peak WindSpeed - Dugout Ranch 250.000 7 6 200.000 5 150.000 4 3 100.000 2 50.000 1 0.000 Average Peak Windspeed m/s The March 6, 2012 Dust event captured by two of the USGS Regional Research Web Cameras. ISKY – co-located with the ISKY TSP particulate sampler and Abajo Peak outside of Monticello Utah. Dust is clearly visible independent of cloud cover and can be distinguished by its color. The dust arrived with the storm front and strong winds from the south. Canyonlands cameras were first deployed in March 2011. Since deployment, dust is clearly evident in 9 of the 13 CODOS dust on snow events recorded in snowpack in Senator Beck Basin, Colorado. TSP Mean load ug/m3/day - ISKY ISKY Clear Day Image 0 Date Time series from the ISKY TSP sampler and averaged peak wind speeds from the Dugout Ranch CLIM-MET station for 2011-2012. Zero lag linear correlation between the series is 0.73. Clearly the two are related despite being separated by 25 miles and extremely varied topography. Seasonal wind rose plots (1998-2012) for Dugout Ranch are presented as well. The strongest winds in Spring and Summer at Dugout Ranch are typically from the south. The highest dust load for one storm from the CODOS database in 2011 was from an event March 21, 2011. This event likely was a primary driver of the very high values of TSP load evident in the 3/14-3-29 2011 sampling period. Dugout Ranch Daily Average Peak Windspeed and CODOS Dust On Snow Events 15 March 6, 2012 Event Daily Average Peak Windspeed m/s 13 Meteorological conditions at the Dugout Ranch CLIM-MET station during the March 6, 2012 dust event. Part of why this event is so clearly recognizable in the camera imagery is that local relative humidity and cloud cover was low during the initial arrival of the dust and winds. WRF (Weather Research Forecasting, http://wrf-model.org/index.php) forecast model results show how lower atmosphere winds were channeled over the Canyonlands area into Western Colorado delivering dust from presumed source areas in northern Arizona. The wind barbs are from the 500hPa level, in this case, around 5500m above mean sea level. Author contact information – Frank Urban, U.S. Geological Survey, MS980 Box 25046, DFC. Denver, CO 80225. [email protected] 11 9 7 5 3 1 2/6/11 3/3/11 3/28/11 4/22/11 5/17/11 6/11/11 7/6/11 7/31/11 8/25/11 9/19/11 10/14/11 11/8/11 12/3/11 12/28/11 1/22/12 2/16/12 3/12/12 Date Daily average peak windspeed from Dugout Ranch with CODOS dust on snow events at Senator Beck Basin in Colorado indicated by the arrows. The majority of the Dust On Snow events correspond to periods of high wind speeds at Dugout Ranch but there are several instances when speeds were low. Additionally, the highest speeds at Dugout precede the listed date for the DOS events due to the geographic offset. There are many strong storms that do not produce DOS and a comprehensive storm by storm analysis and comparison between Canyonlands instrumentation and stations local to Senator Beck Basin is needed to fully understand the linkages and differing storm types and paths. The most recent DOS event is highlighted.