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List of physical geography research projects

For a description of what Physical Geography entails and a list of Faculty performing research in this area, please visit the Physical Geography Specialty Page.

Current Research

Collaborative Research: Landscape-level Measurements of and Controls on Wildfire Spread Rates

SDSU PI: Douglas Stow, National Center for Atmospheric Research PI: Janice Coen, US Forest Service PI: Philip Riggan

National Science Foundation - Geography and Spatial Science Program

Observing and measuring wildfire spread at landscape scales is challenging due to the transient, hazardous nature of wildfires and the spatially heterogeneous conditions in which they occur. Theories about fire spread mechanisms and estimated rates have emerged from tabletop laboratory experiments and small prescribed fires in uncharacteristic weather conditions, or large area estimates based on imprecise fire perimeter data and long times between observations, allowing only estimates of average growth rates. The study's primary merit is the ability to observe and interpret fire spread mechanisms and to measure spatially varying FSR and wind speeds along a fire line, made possible by a novel approach to delineating fire fronts and measuring their movements from precisely registered, orthorectifed ATIR images. Such measurement and analysis of FSR has not been possible at scales that are requisite to understanding fire behavior its dependence on its drivers: fuel properties, topography and wind. Frequent and detailed tracking of moving flaming fronts can only be achieved with high resolution ATIR imaging, conducted such that the actively burning front can be lingered upon and the entire wildfire perimeter can be repeatedly mapped. Our approach to empirically relate wildfire spread and characteristics to vegetation fuel properties, terrain and wind at the landscape scale is novel and potentially transformative in that it addresses delineated fire spread units as units of spatial analysis. The novel top-down approach to inferring fuel, terrain and wind influences on FSR is based on state-of-the-science spatial statistical and geo-visualization techniques. This addresses a critical need for landscape-level knowledge on wildfire spread rates and processes.


Vegetation Mapping at NALF San Clemente Island, Naval Base Coronado, California

US Navy and Army Corps of Engineers

In an effort to support both conservation and management decisions on Naval Auxiliary Landing Field (NALF) San Clemente Island, a vegetation and land cover map is being developed by researchers at San Diego State University’s Center for Earth Systems Analysis Research (CESAR) and Soil Ecology and Restoration Group (SERG). A vegetation classification and mapping procedure incorporating previously defined alliances from maps, reports, and vegetation surveys has been developed. Vegetation types in this classification scheme follow categories recommended by the Manual of California Vegetation. Through the imaging company NEOS, CESAR conducted aerial image acquisition and began digital image processing of San Clemente Island in fall of 2015. An object-based classification of georeferenced and orthorectified imagery and canopy height information from a recent normalized digital surface model is under development using Trimble’s eCognition Developer software. This image classification method provides users with a powerful alternative to traditional classification and mapping by generating objects (groups of contiguous pixels) of different shape and size that can be meaningfully categorized based on their texture, context, and geometry and spectral properties. In addition, we are conducting extensive field-based vegetation surveys as a complementary part of the overall mapping effort.



Tijuana Watershed Projects

This umbrella website is designed to inform general Tijuana River Watershed (TRW) stakeholders, researchers, and the public about both the physical and human characteristics of the watershed. It also serves as a forum for the exchange of research results and projects related to the TRW.

The statements found on this page/site are for informational purposes only. While every effort is made to ensure that this information is up to date and accurate, official information can be found in the university publications.

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