Visualizing barrier island dune topographic state space

My graduate student Jackie Monge recently completed a thesis that examined the similarities in dune topography among different barrier island morphologies.   We found that dune topography tends to converge around two basic forms (top graphic), an overwash-reinforcing topography associated with microtidal barrier island dune topographies. and an overwash resisting topography characteristic of mesotidal barrier islands.  This convergence held up over a range of cluster groupings of barrier island morphology (middle graphic). Dune topography was compared on the basis of lidar-derived indices of landscape patch structure of elevational ranges, directional spatial autocorrelation structure of elevation, and frequency distribution data for elevation (bottom graphic, lidar for a site on Sapelo Island). Her thesis can be accessed here.

Severe thunderstorm warning bias

One of my master's students Megan White recently completed her thesis on the relationship between the issuance of severe thunderstorm warnings and underlying demographic variables. The map above shows the distribution of National Weather Service severe thunderstorm warnings. Each grid cell represents the number of severe thunderstorms issued over the five years of the study. Megan's thesis can be accessed here.

In this map of local R2 derived from geographically weighted regression, one can see the varying relationship between the number of severe thunderstorm warnings and the properties of the underlying demographic template. Boundary lines are National Weather Service forecast zones.  White and red shades indicate areas where there was a stronger association between demographic variables (population count, percent white, and median income) and severe thunderstorm warning issuance.  Several cities stood out for their propensity to issue warnings that more frequently coincided with increasingly populated, whiter,  higher income areas.  Forecasters in Washington DC, Nashville, the Atlanta I-75 corridor, and St. Louis were more likely to  to take into account these underlying demographic variables when alerting the public about severe weather.

Results of urban pollen monitoring pilot study

Some of the pollen collected during this project. I have not yet had time to go back and identify the pollen. If you are interested in doing an independent study, thesis, or dissertation related to this work, let me know. 

Conceptual framework for a study of how land use, pollen forage, and beekeeping interact.  The dashed line indicates the feedback linking back to land cover. As beekeeping becomes more difficult and pollination services more expensive or harder to procure for bee-dependent crops, more land may be converted to agriculture to make up for shortfalls in crop production.

Amino acid composition for the pollen collected from a colony at the 5th Street Apiary in Lexington, KY.  Although these samples were collected approximately one month apart from the same hive, they show significant differences in the quantities of amino acids. The most essential amino acids for honey bees are isoleucine, leucine, and valine. HPLC chemical analyses were at UK in the Environmental Research Training Laboratory.

Pollen monitoring in urban apiary

Photos documenting a pilot study I conducted with the beekeepers who run the 5th Street Apiary here in Lexington during summer 2013. This work is part of project I have been incubating for several hundred years. The only thing lacking now is a student who would be interested in expanding it for a thesis or dissertation. The study I have been envisioning examines relationships between pollen composition collected by honey bees, its nutritional content (as measured by amino acids), and surrounding land uses.  Here is a summary of a recent NSF proposal submission.

This photo at left shows the iButton temperature probe we installed in the hives to track the internal temperatures. 

These are the colonies monitored for a period of two months. On the front of each hive trimmed in yellow paint are the pollen traps. They collect pollen off the foraging bees as they return to the hive.

Paint pole dune topographic mapping

We recently tried out a paint pole-mounted camera as another method to derive topographic maps. We tested our  methods in the dunes on a recent trip to Sapelo Island, GA. At the bottom is the video taken from our Canon Powershot D20.  We used a paint pole purchased from Home Depot and camera mounting equipment sold by PolePixie. The video above is the raw video. We edited this video down and then removed the shakiness before extracting frames in Photomodeler.  The resulting dense point cloud is shown above. The image still requires some post-processing to remove relief introduced by the vegetation, but all in all, the paint pole seems well suited to capture topography.

Kite topographic mapping - UK campus

Here are some of the results of our recent pilot work with kite photography and structure-from-motion topographic mapping.  We were also able to tie in UTM coordinates to the surface we produced. Although not very visible in these photos at left, we established ground control points using chalk spray paint and our GPS. Our Trimble GEOXH gave us coordinates with 0.10 horizontal and 0.20 vertical accuracies after differential correction, which may not be that useful for the small extent and low contrasts in relief shown here.

I would like to continue refining our kite photography and SFM skills. However, there isn't enough time for me to explore this solely  on my own. If you are an undergraduate or graduate student and want to do an independent study, thesis, or dissertation with these techniques, send me an email.

Field class trip to Sapelo Island, Georgia

GEO 721 Field class on ferry to Sapelo Island (above). Video of class (top) taken surreptitiously with our paint pole. Below, from left to right, Tony Stallins, Li-Chih Hsu, Jackie Monge, Shelby Jones, Alex Rittle, and Daehyun Kim.

Daehyun Kim (above) and Tony Stallins (below).

 

Coachwhip (Masticophis flagellum) in the rear dunes, estimated to be about 6 ft in length. 

Kite topographic mapping - Sapelo Island, Georgia

(Above and below) In May, my GEO 721 field class traveled to Sapelo Island Georgia to try out kite photography in the coastal environment. We were using a Canon Powershot camera for video and still photography.  For an idea of what our kite looks like visit the web page for Allsop Helikites. The view above is looking north on Nannygoat Beach, just above the beach entrance off Old Beach Road.

We are using Photomodeler software to create topographic maps derived from photos and video.  The image above was processed in Photomodeler using stills from the video at selected intervals. Because of high wind speeds on the day we flew the kite, our camera mount did not stay in position and we ended up with less than desirable oblique angle photos.  However, reconstructing the topography from the image was still feasible.

Below is the raw video of our flight. We stabilized segments of the video using ProDrenalin software before structure-from-motion reconstruction.