UHH Spatial Data Analysis and Visualization Lab

 
The UH Hilo provides cutting edge technology to better understand the dynamics of our island.  Dr. Ryan Perroy, Assistant Professor at UH Hilo in the Department of Geography & Environmental Science and director of the UH Hilo Spatial Data Analysis and Visualization (SDAV) research lab, enlightened our club with an overview of a number of ongoing research projects including mapping erosion at the summit of Maunakea to detecting invasive tropical plant species with unmanned aerial vehicles (UAVs). He is also in the midst of a multi-year project assessing coastal erosion rates and impacts from sea-level rise at three different locations across Hawaii island, using a combination of existing imagery and topographic datasets and new geospatial data collected with unmanned aerial vehicles. 
 
Dr. Ryan Perroy is originally from Virginia, where he received an undergraduate degree in Physics from the College of William and Mary. He received his PhD in Physical Geography from UC Santa Barbara. He teaches a variety of geospatial classes including GIS, Remote Sensing, and Geostatistics and will be teaching a class on Climate Change and Global Warming this Fall semester.
 
As director of the UH Hilo Spatial Data Analysis and Visualization (SDAV) research lab, he has overseen projects such as the following:
  • Miconia-- this invasive species is taking over our forest.  Using drones to photograph, SDAV is developing computer algorithms to identify the miconia from the photos.
  • Maunakea summit—SDAV is studying the erosion and land change at the summit using 3D laser topography, and analyzing time comparison changes in the summit's geomorphology.  SDAV is also testing drones to replace the expensive laser surveys.  The analysis will compare natural changes vs. man-made changes due to road and other land disturbance.
  • Shoreline change rates—SDAV is studying three areas under a Coastal Zone Management contract with the County Planning Department: Hapuna Beach (sandy beach); Kapoho (subsidence); and Honolii (sea cliff).
  • Climate change—As part of the shoreline study, SDAV will also factor rising ocean levels due to rising ocean temperatures.  Mapunapuna on Oahu is an example of flooding due to rising groundwater due to high tide even with no rainfall.
SDAV has found drones to be good to collect high resolution photos with quick turnaround; their weakness is limited flight time and cost.  The cost for drones vary from thousand to multi-thousands, but need to also include the sensors which can be expensive.  There are strict FAA rules for hobbyists; commercial users such as SDAV need a license.  For historical comparisons, SDAV does use old photos, but is hampered by resolution of older imagery.   The software to process drone data is becoming more user-friendly.  Lower cost open-source requires more technical savvy; need to pay more for more user-friendliness.