My Journey into Remote Sensing for Humanitarian Health
My journey into the world of remote sensing and humanitarian health began with a childhood fascination with geography. As a child, I spent countless hours studying maps, memorizing countries, and learning about borders and capitals. This early passion laid the groundwork for my current professional interests.
My name is Becca and I am a recent graduate at Yale University. In this post, I'll explore how my academic pursuits and experiences have cultivated my understanding and passion for remote sensing in humanitarian health.
Merging Public Health and Geography
I earned my Bachelor of Science from Southern Illinois University Edwardsville (SIUE) where I found my dual interests in public health and geography. This led me to major in Public Health and minor in Geographic Information Systems (GIS). During my studies, I took a course in remote sensing and air-photo interpretation that opened my eyes to the vast possibilities of applying remote sensing techniques to public health issues ranging from infectious diseases to humanitarian health. I knew I wanted to continue to learn as much as possible. After graduating from SIUE and working at a local health department for a few years, I decided to enroll in a Master of Public Health with a concentration in Epidemiology of Microbial Diseases at Yale University.
Presenting my thesis at Yale School of Public Health’s Epidemiology of Microbial Diseases Research Day
Crafting the Thesis
During my master’s program at Yale, I collaborated closely with my thesis advisors at the Yale School of Public Health’s Humanitarian Research Lab (HRL). Inspired by my interests in humanitarian health and remote sensing, my advisors and I crafted a topic: develop a standard remote sensing method for assessing food security using Integrated Food Security Phase Classification (IPC) scales in communities experiencing conflict. Often, remote sensing may be the only tool available for food security assessments in conflict settings. But if there are no standardized methods, these assessments may lead to highly variable and often non-interoperable results.
IPC is an international standard for determining both the severity and magnitude of acute and chronic food insecurity, along with malnutrition, to inform programming, policy, and emergency response. In the case of my thesis, I focused primarily on acute food insecurity. Acute food insecurity has five phases ranging from Phase 1 (None/Minimal) to the most severe, Phase 5 (Catastrophe). Phase 5 may also be classified as Famine if other criteria are met.
Scope
I chose to study South Sudan due to its severe food insecurity, exacerbated by climatic shocks, conflict, and economic instability. Specifically, the counties of Gogrial West and Rumbek Centre were selected as areas of interest. This study aimed to investigate how thermal activity correlates with conflict events, potentially contributing to higher IPC levels, as well as how agricultural practices may influence lower IPC levels. In other words, we were looking to see if thermal activity could be correlated with food insecurity.
Methodology
Imagery was captured annually between 2017 and 2023, specifically between April 15th and June 15th each year. This time frame coincides with the sowing and lean seasons, periods critical for assessing food insecurity levels.
Multispectral imagery was sourced from the Sentinel 2 EO Hub. Using ArcGIS Pro, I processed the images to prepare them for analysis. I applied a Normalized Burn Ratio (NBR), leveraging near-infrared and shortwave infrared bands to detect burned areas based on reflected radiation. The NBR scale ranges from -1 (burned area) to 1 (healthy vegetation).
Subsequently, I classified the image into two groups: Thermal Activity, representing values of -0.2 and lower, and all other areas. I quantified the number of pixels in each group and converted these counts into square kilometers to assess associations with food prices, IPC levels, conflict events, and fatalities.
Classified observed thermal activity in Gogrial West from 2017 to 2023
Findings
The findings from this thesis reveal several significant correlations. Firstly, there is a statistically significant positive correlation between IPC levels and both food prices and conflict events. However, the most notable discovery is a statistically significant negative correlation between thermal activity and food prices. This suggests that these areas may be participating in non-conflict related land clearing to enable planting for the next season.
These results highlight the need for more research to fully understand the relationship between thermal activity, food prices, and IPC scales. Developing standardized remote sensing methodologies to support IPC assessments could greatly enhance our ability to monitor and respond to food insecurity globally, potentially leading to more rapid and accurate IPC assessments.
Preparations for my presentation at Humanitarian Networks and Partners Weeks in Geneva, Switzerland
Presenting my Project at American Association of Geographers: Visualizing Patterns of Hunger in Afghanistan
In a recent project focused on food security, my team and I worked on an assessment of the uneven distribution of hunger in Afghanistan, measured through Food Consumption Scores (FCS). The study spanned multiple years and examined disparities across provinces in Afghanistan, with a particular focus on the districts within Ghor province. The motivation behind this research was to address the limitations of traditional food security analyses, which often overlook significant variations in needs, especially in remote regions like Ghor province.
Our approach involved statistical analysis, including calculations of skewness and coefficients of variation for FCS at both provincial and district levels within Ghor. Additionally, we utilized ArcGIS Pro to map FCS categories, enabling us to visually explore spatial relationships. These maps revealed substantial spatial variability in FCS, underscoring our statistical findings that FCS scores alone might not adequately capture the true extent of hunger in diverse contexts.
These insights highlight the necessity of bridging existing gaps in understanding and addressing hunger disparities effectively. As of now, the project has been completed, and we are in the process of preparing it for publication. Stay tuned for further updates as we aim to share our findings and contribute to advancing discussions on food security strategies in diverse and challenging environments. I had the opportunity to present these findings at the American Association of Geographers (AAG) Annual Meeting in Honolulu, Hawaii.
Presenting my project at AAG Annual Meeting in Honolulu, Hawaii
The Road Ahead
Reflecting on my journey from a childhood fascination with geography to a career in remote sensing and humanitarian health, I am inspired by the potential of geospatial technology to address global challenges. My work on standardizing remotely sensed data for food security assessments has been both a significant learning experience and an opportunity to contribute to meaningful solutions.
I am deeply grateful for the support from Yale HRL, and for the chance to present the findings of my research at Yale School of Public Health's Epidemiology of Microbial Diseases Research Day, AAG Annual Meeting, and Humanitarian Networks and Partners Week in Geneva, Switzerland. Although I recently graduated from Yale University, I am excited to continue exploring standardization of remote sensing methodology for food security assessments at Yale HRL.
Thank you for taking the time to read about my research and journey. For those interested in a more detailed exploration of my research, you can access my full thesis here.