Research

Guiding Concepts

I am driven by the desire to have an impact in human adaptation to anthropogenic climate change. Specifically, I focus on post-disaster adaptation, with an emphasis on hurricanes and coastal change, and out-migration. In this, I am most interested in a few key concepts and questions:

Adaptation: Why do some households adopt in situ strategies for adaptation, while others leave?

Migration: Do disasters disrupt existing migration patterns in and out of an area, or simply accelerate them?

Displacement: To what extent do displacement patterns increase permanent migration?

Temporal Change: How do people change their perspectives on adaptation strategies as environmental conditions deteriorate?

Governance & Policy: How do federal policies influence state and local plans, and therefore change the built environment?

Equity: How do we address historic inequities, especially those that have placed at-risk communities in harm’s way, during recovery?

I intend to develop a body of research that can inform improved hazard mitigation and recovery plans to increase resilience in two ways. First, by capitalizing on organic migration patterns to facilitate out-migration from vulnerable areas without replacement in-migration; and second, by emphasizing receiving communities to help fund and support those displaced in the direct aftermath of disasters.


Upcoming Conference Presentation

I will be presenting at PAA on a segment of my dissertation focused on vulnerability replacement dynamics through migration in the aftermath of major hurricanes in eastern North Carolina, with implications for barriers to planning for resilient de-growth. Specifically, I will focus on the development and validation of an address-to-address database derived from data purchased from the credit agency, TransUnion.

The specific data is TBD, but it will be in session 1101-Climate Change and Migration, April 12-15.


Postdoctoral Work

My postdoctoral work with Dr. Elizabeth Fussell leverages privileged census data to study neighborhood attainment outcomes for migrants from Puerto Rico following both the economic crisis beginning in 2007, and exposure to Hurricane Maria in 2017. Using this comparison, we hope to better understand the implication of migration in response to slow- versus rapid-onset disasters, precipitated by both natural and non-natural hazards.

Additionally, we are pursuing a project that quantifies historic hurricane exposure across the United States, to create an analogous measure of vulnerability to the 100-year floodplain that centers concrete experiences. This “hurricane burden” will mirror measures for the burden of disease used in public health.


Dissertation

Migration Patterns and Household Adaptation Dynamics in Response to Hurricanes, Floods, and Sea Level Rise

My dissertation followed a three paper format, all of which substantively centered on environmental migration and environmental displacement, specifically as driven by flood risk and hazards. The broader goal of my research is to better understand the tensions experienced by residents regarding the decision to leave or stay in a home and/or community under deteriorating environmental conditions, as well as the risks associated with leaving.

The first paper focused on a community at the vanguard of climate change to better understand residents’ perspectives on adaptation and out-migration while experiencing rapidly deteriorating environmental conditions. I used a repeated measures analysis on data from two waves of a survey, the first of which was distributed in 2017, in the aftermath of Hurricane Matthew (2016), and the second of which was distributed in 2020, after exposure to both Hurricanes Florence (2018) and Dorian (2019). The analysis also considered exposure to saltwater intrusion, allowing for the consideration of compounding rapid-onset (hurricanes) and slow-onset (saltwater intrusion) hazards.

I found (1) that saltwater intrusion was associated with heightened risk perception, (2) increased risk perception was associated with increased openness to moving; and (3) openness to moving was associated with action. However, we also noted that the effects may be time limited without additional hazard exposure.

Farmland impacted by saltwater intrusion in the study area

The second paper zoomed out to the entirety of eastern North Carolina, while retaining individual-level analysis to study how the intersection of flood risk and repeated disaster exposure can synergistically impact migration. Specifically, I examine the impact of Hurricanes Matthew (2016) and Florence (2018) in affected and control areas across the Coastal Plain of North Carolina, employing a novel, panel dataset containing the addresses (with dates of initial occupancy) of millions of individuals in North Carolina between January 2016 to July 2020. Compared to traditional migration research, my work addresses gaps in the literature by operating at a finer temporal scale and a higher resolution of observations, enabling a more nuanced understanding of migration flows (Hori and Schafer 2010).

I found that individuals affected by hurricanes who did not live in floodplains were more likely to move into a new residence within the floodplain, however, the colocation of vulnerability and exposure was associated with more resilient migration (e.g. movement from the floodplain to residences outside of the floodplain). However, floodplains retained overall vulnerability at the regional level as new individuals moved into floodplain residences.

Post disaster migration into and out of floodplains in eastern North Carolina. Despite nearly a tenth of floodplain residents moving out of floodplains, larger regional vulnerability remained constant due to new in-migration.

Finally, I pivoted to an examination of the predominant policy intervention enabling retreat from high hazard areas: federally funded floodplain buyouts. Specifically, I looked at neighborhood attainment outcomes for a sample of homeowners from Harris County, TX who moved in the aftermath of Hurricane Harvey (2017). Prior work have compared buyout participant origin to destination conditions, buyout participant outcomes to those who rebuilt in place, and outcomes for different segments of buyout participants within the same program. My work does more to isolate the effects of the buyout program by comparing buyout participant neighborhood attainment outcomes to comparable homeowners (controls) that moved without buyout participation over the same time period.

Using a quasi-experimental design, implemented through a propensity score matching (PSM) analysis, I found that, on average, members of both buyout and non-buyout groups moved into areas with better socio-economic metrics (relative to their origins) and that a strong majority moved out of floodplains. However, I did not find that buyout participants experienced outcomes significantly different to those of non-buyout movers. I hypothesize that this was the result of the strength of the Houston-area housing market, which rebounded rapidly in the aftermath of Hurricane Harvey.

Map showing a section of our study area, demonstrating the colocation of buyout and control households used in my analysis.

Prior Conference Presentations and Posters

Frankenberg, Elizabeth, Todd BenDor, Philip Berke, Cassandra Davis, Nathan Dollar, Anna Gardner, Miyuki Hino, Nikhil Kothegal, Rene Iwo, Richard A Luettich, Tamlin Pavelsky, Brian Frizzelle, Michael Piehler, Nora Louise Schwaller, John Ratcliff, Anne Smiley, Antonia Sebastian, Conghe Song, Chao Wang, Ted Mouw. “The Dynamics of Extreme Events, People and Places—a Convergent Approach to Understanding Flooding Exposures and Impacts.” In AGU Fall Meeting 2021. AGU, 2021.

Schwaller, Nora Louise. Transformative Climate Planning: Incorporating, measuring, and actualizing equity. Presented at the Association of Collegiate Schools of Planning annual conference, online (2021, October 7). Round table participant.

Schwaller, Nora Louise, Todd K. BenDor. Changing Perspectives After the Storm: A Pre-Post Evaluation of Adaptive Decision Making. Presented at the Natural Hazards researchers’ meeting, online. (2021, July 15). Parallel session presentation.

Schwaller, Nora Louise. Dichotomous or progressive choices: in situ protection and retreat as strategies for climate adaptation. Presented at the At What Point Managed Retreat Conference, Columbia University, online. (2021, June 22). Parallel session presentation.

Schwaller, Nora Louise, Mai Thi Nguyen, Leah Campbell. (2020, November 4, anticipated). (Mis)trusting the Process: How complications in the buyout process can degrade public trust. Presented at the Association of Collegiate Schools of Planning annual conference, Toronto, Canada.

Campbell, Leah, Mai Thi Nguyen, Nora Louise Schwaller. (2020, November 4, anticipated). Barriers to Effective Local Administration of Post-Hurricane Matthew Buyouts in North Carolina. Presented at the Association of Collegiate Schools of Planning annual conference, Toronto, Canada.

Branham, Jordan, Nora Louise Schwaller. (2020, November 4, anticipated). Changes in the Water: the impact of natural hazards vulnerability and exposure on population change. Presented at the Association of Collegiate Schools of Planning annual conference, Toronto, Canada.

Hino, Miyuki, Todd BenDor, Jordan Branham, Nikhil Kaza, David Salvesen, Nora Louise Schwaller, Antonia Sebastian, Shane Sweeney. (2020, November 4, anticipated). A Parcel-Scale Analysis of Municipal Floodplain Management in North Carolina. Presented at the Association of Collegiate Schools of Planning annual conference, Toronto, Canada.

Schwaller, Nora LouiseTodd BenDor. (2020, July 16, anticipated). Differential Residential Perspectives on In-Situ Protection and Retreat for Climate Adaptation. Presented at the Natural Hazards conference in Boulder, Colorado.

Schwaller, Nora Louise, Mai Thi Nguyen. (2019, October 24). Finding Community When Hurricanes Hit Home. Presented at the Association of Collegiate Schools of Planning annual conference, Greenville, SC.

Schwaller, Nora Louise. (2019, July 15) Displacement and Return: migration patterns in the Aftermath of Hurricane Maria. Presented at the Natural Hazards conference in Boulder, Colorado.

Schwaller, Nora Louise, Jordan Branham. (2019, June 22). Disaster Exposure and Mitigation: The Impact of Major and Minor Flood Events on Population Loss. Presented at the At What Point Managed Retreat Conference, Columbia University, New York City, NY.

Schwaller, Nora Louise, Jordan Branham. (2019, May 21). Disaster Exposure and Mitigation: The Impact of Major and Minor Flood Events on Population Loss. Presented at the Association of State Floodplain Managers Foundation Conference, Cleveland, OH.

Schwaller, Nora Louise, Mai Thi Nguyen. (2018, October 26). Impacts of Hazard Mitigation Grants on Individual and Community Level Post-Disaster Resilience. Presented at the Association of Collegiate Schools of Planning annual conference, Buffalo, NY.


Like my work and want to know more? Interested in collaborating? I’d love to hear from you:

nschwall [at] live [dot] unc [dot] edu