Brandon J. Vogt

A High-Resolution Lightning Map of the State of Colorado

AbstractFor the state of Colorado, 10 years (2003–12) of 1 April–31 October cloud-to-ground (CG) lightning stroke data are mapped at 500-m spatial resolution over a 10-m spatial resolution U.S. Geological Survey (USGS) digital elevation model (DEM). Spatially, the 12.5 million strokes that are analyzed represent ground contacts, but translate to density values that are about twice the number of ground contacts. Visual interpretation of the mapped data reveals the general lightning climatology of the state, while geospatial analyses that quantify lightning activity by elevation identify certain topographic influences of Colorado’s physical landscape. Elevations lower than 1829 m (6000 ft) and above 3200 m (10 500 ft) show a positive relationship between lightning activity and elevation, while the variegated topography that lies between these two elevations is characterized by a fluctuating relationship. Though many topographic controls are elucidated through the mappings and analyses, the major finding of ...

Exploring Cloud-to-Ground Lightning Earth Highpoint Attachment Geography by Peak Current

Abstract This study applied remotely sensed cloud-to-ground (CG) lightning strike location data, a digital elevation model (DEM), and a geographic information system (GIS) to characterize negative polarity peak current CG lightning Earth attachment behavior. It explored the propensity for (i) flashes to favor topographic highpoint attachment and (ii) striking distance (a near-Earth attachment force) to increase with peak current. On a 16 000 km2 10-m DEM covering a section of southeast and south-central Colorado, a GIS extraction method identified approximately 5000 hilltop and outcrop highpoints containing at least 15 m of vertical gain in a 300-m radius neighborhood with a minimum horizontal separation of 600 m. Flashes with peak currents ranging from −20 to −119 kiloamps (kA), collected between February 2005 and May 2009, were subdivided into 10 kA classes and mapped on this modified DEM. Buffers of 100-, 200-, and 300-m radii created around each highpoint were used to assess the hypothesis that striki...

Using Digital Earth to Expose Students to GIScience

Students in U.S. geography programs face particular challenges that may discourage them from taking advanced GIScience courses and considering geospatial careers. This article provides a preliminary discussion of the development, delivery, and evaluation of a University of Colorado Colorado Springs sophomore-level, required geography course designed to address this concern. The course, Digital Earth (DE), introduces students to the principles, concepts, and applications of major geographic information technologies (GITs) early in their academic careers. The success of DE is evaluated by examining the extent to which the course excited students about GIScience and motivated them to take higher level elective geospatial courses. Results suggest that DE generates considerable student interest in GIScience, prepares students reasonably well for elective courses, and greatly inspires them to seek a geospatial career.

Visualizing Summertime Lightning Patterns on Colorado Fourteeners

In the context of lightning avoidance, this article explores temporal and spatial patterns of cloud-to-ground lightning strikes to Colorado Fourteeners, the popularly summited set of mountains that exceed 4,267 m (14,000 ft). The article describes the Fourteener concept, examines trends in lightning fatalities and injuries, and reviews thunderstorm climatology across the greater Colorado landscape. Fifteen years (1996–2010) of summertime lightning activity at near-summit locations are examined. Three measures characterize lightning activity for fifty-four Fourteeners: (1) overall strikes received, (2) lightning days, and (3) the time of day when lightning first strikes. Maps, histograms, and ranked lists identify trends and anomalies generated from the three measures. Examples of highest potential risks include Pikes Peak for Fourteener, Front Range for mountain range, and the third week of July for time of summer. The results can help avoid lightning when making long-term plans to visit Fourteeners and can heighten awareness when on Fourteeners. In addition to lightning avoidance, the article contributes to mountain geography and related atmospheric, physical, and social sciences.

Informal trail creation: hiking, trail running, and mountain bicycling in shortgrass prairie

ABSTRACT This study considers initial impacts on vegetation cover caused by mountain bicycling, trail running, and hiking in a shortgrass prairie environment. Vegetation cover measurements were taken at multiple intervals following experimental recreational use on three uphill and three downhill trail segments. All three activities caused statistically significant increases in bare ground cover between the first baseline measurement and post-treatment sampling one year later. Short-term effects were more variable: walking and bicycling caused statistically significant increases in bare ground, but running did not. The study suggests that impacts to vegetation differ not just between uses, but also within a single type of recreational activity depending upon site-specific characteristics, and that the timing of use and recovery are important factors in informal trail creation. The rapid creation of trail impacts also has management implications, especially as recreational pressures increase and recreationists seek more challenging terrain and opportunities off-trail. This research suggests that the dynamics of trail formation from running deserve further attention and likely differ from hiking or mountain biking impacts.

The Silverton Field Experience: A Model Geography Course for Achieving High-Impact Educational Practices (HEPs).

Abstract High-Impact Educational Practices (HEPs) are a set of specific teaching and learning approaches proven effective in university education. This paper focuses on the benefits derived from utilizing three particular HEPs (inquiry-based collaborative activities, undergraduate research, and experiential learning) while teaching a snow and ice field course titled “Silverton Field Experience.” Student evaluations and instructor feedback reinforce the notion that HEPs encourage deep learning. Deep learning is manifest through increased enthusiasm and participation as well as learning in ways that are meaningful, creative, and stimulating. In terms of pedagogy in geography, these HEPs also create an expanded sense of place and a new way to encourage spatial thinking. The HEPs outlined here are replicable in different geography sub-disciplines and among different settings in higher education and prove exciting to an audience of pedagogic researchers and teacher-practitioners in geographical education.

Terrestrial laser scanning and exploratory spatial data analysis for the mapping of weathering forms on rock art panels

Rock art conservators are faced with complex decisions to prioritize rock art panels for protection from destructive forces of weathering. We provide a system to facilitate such decision making that blends traditional remote sensing with interactive techniques of exploratory spatial data analysis. Our system, ‘mapping weathering forms in three-dimensional (3D)’ (MapWeF) uses a 3D laser scanning device for sub-centimetre data collection from in situ rock surfaces. After image and digital surface model processing, key rock weathering forms are highlighted through classification. Supervised classification builds training classes as a user probes known weathering forms. Guided by these training classes, the user then interactively brushes and assembles pixels from scatter plots until the user is confident that all manifestations of a particular weathering form have been mapped. The purpose of MapWeF is to construct detailed maps that highlight regions of decay on rock art panels. These maps can help rock art conservators take action on panels in need of urgent preservation or remediation.