2015 08 14 Meeting with Iris Stewart-Frey in Santa Clara University

Iris Stewart-Frey


Iris Stewart-Frey 

Associate Professor, Department Chair
Office: Varsi Hall 219
Phone: (408) 551-7186
Email: istewartfrey@scu.edu

Ph.D., Stanford University

Teaching and Research Vision

My teaching vision is to engage and inspire every student in my class to become an active learner. I believe that if students have a solid foundation in the basics, a keen interest, and knowledge on how they learn best, they are well equipped to learn in the classroom and well beyond. I strive to kindle this interest, provide foundational knowledge in Environmental Studies and Sciences, and have students explore their learning preferences through a variety of teaching strategies, such as discussions, research projects, student presentations, workshops, fieldwork, case studies, and traditional lectures. In my classes we explore the geological, atmospheric, water, and soil processes and their interactions with society, pondering how plate tectonics is relevant for cell phones,  why more than half of the world?s population today does not have access to the quality of water systems available to the citizens of Rome 2,000 years ago, and how in 200 years we have managed to lose half of the topsoil of the Great Plains, which took hundreds or thousands of years to form. I also teach Geographical Information Systems (GIS), an approach to mapping and spatial analysis, which is used in many academic and professional fields. In the class, students conduct a research project using GIS. Several longer term student projects, such as vegetative mapping at the Blue Oak Ranch and Reserve and an investigation into food access and environmental justice issues in Santa Clara County have evolved from this classwork.
My research interests encompass environmental issues that affect the water cycle and water supply. I have worked on both shallow groundwater pollution issues and on surface water processes that are related to climate variability and climate change.
Leaching of pesticides to the water table is a common occurrence in intensively farmed agricultural regions. I have developed a type transfer function model (TTF) to assess pesticide leaching to groundwater at the regional scale. I have then used this model with in a GIS (Geographical Information Systems) framework to estimate Atrazine (a common herbicide) concentrations that would result at the water table from routine farming operations in the San Joaquin Valley in California (Stewart and Loague, 2003; 2004).
In the arid regions of western North America, nearly all precipitation arrives in the Winter and is stored as mountain snowpack. Hence, the spring snowmelt runoff is the main component for the region?s water supply, delivered to urban and agricultural regions through the summer drought period. I analyzed changes in the timing of the spring snowmelt runoff across western North America that have resulted from warmer air temperatures and precipitation changes to date (Stewart et al., 2005). This work documented that streamflow timing for snowmelt dominated streams has changed toward an earlier spring over the past several decades and for an area much larger than previously recognized (Fig. 1). These changes could have serious implications for the water supply of the dry southwestern regions and beyond. For another study, I used the relationships between past streamflow and climate to assess the impact of a warming climate on streamflow timing under a business-as-usual climate change scenario for the 21st century (Stewart et al., 2005). In follow-up work, I and collaborators investigated if the 2000 ? 2010 decade, which to date had been recorded as the warmest on record, had seen an acceleration of streamflow timing shifts using trend analysis and a statistical model (Fritze et al., 2011). This work found that although an acceleration of streamflow timing shifts is not clearly indicated, a set of highly vulnerable basins has experienced runoff regime shifts such that previously snowmelt dominated watersheds are now mainly rain dominated .