Changes in oceanic dynamics in the Tropical Pacific Ocean can have an influence on large-scale patterns like El Niño-Southern Oscillation (ENSO) dynamics and global climate. Understanding the magnitude of ocean temperature and salinity changes in this region in recent decades can help us understand the impacts of climate change and inform predictions. This study compares temperature and salinity in the Tropical Pacific during the winter and spring of 2025 to ship transects from the 1950s-1980s. Seaglider data were collected by the UW Student Seaglider Center’s Seaglider SG195 which was deployed off of the R/V Sikuliaq in November 2024. The Seaglider gathered data on temperature, salinity, and depth-averaged currents along a transect from the Equatorial Pacific (4° 39' 24”, -139° 53' 34") to Honolulu, Hawaii (21° 15' 0", -157° 52' 0"). These data were compared to CTD data from historic ship-based datasets, obtained from NOAA world ocean database, covering the same region and season (Winter to Spring). Preliminary analysis shows a connection between subsurface changes and the current ENSO phase. Since temperature variability in the Tropical Pacific is a key driver of ENSO dynamics, this research can support others in understanding whether the Tropical Pacific may be trending toward La Niña or El Niño baseline conditions and thus what the Equatorial Pacific will look like in upcoming decades.

Nitrous oxide (N₂O) is an important greenhouse gas that depletes stratospheric ozone and is 300 times more potent than carbon dioxide (CO₂) over 100 years. Emissions have increased by 40% since 1980, and N₂O has been accumulating in the atmosphere at an unprecedented rate due to its long lifetime. The rapid rise of N₂O emissions primarily come from soil microbes that respond to the increased usage of agricultural fertilizers which help supply global food demand. Other notable sources include combustion, wastewater treatment, and industrial processes such as nitric acid production. Despite the importance of N₂O, atmospheric observations have limited spatial coverage. Remote sensing presents an attractive solution to dramatically increase spatial sampling. Here we assess the feasibility of using remote sensing to measure N₂O concentrations from sub-orbital platforms. Sub-orbital remote sensing platforms provide a testbed to determine the future viability of space-borne measurements. Our work uses an airborne instrument: the Airborne Visible InfraRed Imaging Spectrometer (AVIRIS). AVIRIS is a full spectral range airborne imaging spectrometer that measures the radiance of the Earth’s atmosphere from 380 - 2510 nm wavelengths. We hypothesize that band ratios from AVIRIS can be used to detect N₂O plumes. We begin by selecting the highest emitting point-source facilities in cloud-free flight tracks. Preliminary plumes will be verified by shape and direction according to meteorological data and consistency with facility layouts. We first test this methodology on CO₂, as previous studies have demonstrated successful detections with AVIRIS. CO₂ will serve as a proof of concept before applying our method to N₂O, which is more challenging to detect due to its lower atmospheric abundance and weaker spectral signature. 

Student-run environmental research organizations allow students to gain real-world experience while conducting research that leads to a greater understanding of the environment. These programs suffer from high turnover when students graduate and take the knowledge they have acquired with them. Loss of institutional knowledge is a major issue for organizations that rely on students and mitigating this loss is essential to ensure the success and longevity of a program. This project finds how student-run environmental research organizations can better preserve institutional knowledge through a case study with the Student Seaglider Center (SSC): a student-run lab at the University of Washington’s School of Oceanography. My research is centered around studying the efficacy of a new training class for students interested in joining the SSC through tracking how self-reported competency in various subject areas changes throughout the quarter. Their results are compared to students who are already in the lab and did not take the class. This research helps determine effective methods to transfer knowledge from experienced members to newer ones, which helps the SSC operate efficiently in the future and continue to do impactful environmental research. It also benefits other student-run research programs by providing recommendations on how they can reduce the loss of institutional knowledge when students graduate.

Access to nutritious food is essential for survival. Yet, a significant portion of the global population, including over 20% of adults in Seattle and 20% of University of Washington students, struggle with food insecurity. This issue is particularly pronounced in minority communities and is exacerbated by the presence of food deserts – areas lacking local grocery stores. This study aimed to answer a critical question: could urban agriculture be a viable solution for alleviating food insecurity in Seattle’s food deserts? During my internship with City Fruit, I gathered observational data on the impact of food insecurity on Seattle residents and collected additional data independently. I identified food deserts using the United States Department of Agriculture (USDA) Food Research Atlas and analyzed their racial demographics. I also used Geographic Information System (GIS) mapping and public data to assess the available open space for urban agriculture within these areas and calculated the necessary yields of fruits and vegetables to support food-insecure residents. My findings indicate that sufficient space exists to meet 75% of the fruit and vegetable needs of the 103,000 residents in Seattle’s food deserts. While implementing such a project would present challenges, it could reduce grocery bills for food desert residents by 15%, foster community connections, improve air quality, and mitigate the urban heat island effect for the entire city. This research underscores the potential of urban agriculture to combat food insecurity and promote sustainability in urban environments, offering a promising solution to a pressing issue.

The rapid evolution of antimicrobial resistance (AMR) in bacteria poses a critical global health challenge, predicted to cause 10 million deaths annually by 2050 if left unaddressed. AMR genes frequently reside on plasmids– small, circular DNA separate from bacterial chromosomes. These plasmids spread between bacteria through horizontal gene transfer (HGT), where genetic material moves directly from one cell to another, rapidly disseminating resistance genes across populations and species. In contrast, vertical gene transfer (VGT) occurs during bacterial reproduction, passing genes from parent to daughter cells. The machinery plasmids use for HGT imposes a fitness cost on the host, slowing its growth and reproduction (VGT). This means plasmids typically face a trade-off: investing resources in HGT limits the host’s ability to reproduce efficiently through VGT. My research uncovered a “trade-off-breaking mutation” that simultaneously enhances both HGT and VGT, accelerating the spread of AMR genes. Such mutations have significant public health implications, potentially leading to highly virulent, drug-resistant bacterial strains. I am creating a genotype-to-phenotype map to link specific plasmid mutations to their effects on HGT and VGT rates, aiming to understand the dynamics of resistance spread. This work involves verifying mutations in our mutant plasmid library using targeted sequencing techniques and applying the Luria-Delbrück method, a specialized approach developed by my mentor, Dr. Olivia Kosterlitz, to measure gene transfer rates. By analyzing these mutations, I seek to uncover how some plasmids avoid the typical trade-offs, enabling them to reproduce quickly while spreading resistance efficiently. Understanding the relationship between HGT and VGT is critical for predicting how antibiotic resistance evolves and for developing strategies to slow its spread. This research reveals the importance of trade-off-breaking mutations in resistance management, providing new insights into how we might combat one of our time's greatest public health challenges.

Bacteria can shuttle pieces of DNA between unrelated cells via a process called horizontal gene transfer (HGT). Genes that undergo HGT (i.e. mobile genes) evolve in different host bacteria with different genomic backgrounds, which can influence the types of mutations the mobile gene acquires. Studying the effect of HGT on mobile gene evolution is important as many clinically relevant antibiotic resistance genes are mobile. In a prior study, we used a simple model to simulate mobile gene evolution as they engage in HGT. Under the simple model, the mobile gene evolves in only one species at a time. With this model, we found that fitness landscape similarity between two host species engaging in HGT is highly indicative of the effect HGT has on mobile gene fitness outcomes (i.e. whether performing HGT has a positive, negative, or neutral effect on fitness). We expanded the simple model into a more ecologically realistic consumer-resource model (CRM), in which the mobile gene continuously transfers between species. We observed similar outcomes between the two models; however, in the CRM there was an increase in cases in which performing HGT had a positive fitness effect. We hypothesize that the CRM highlights features like the continuous existence of host species, resulting in constant gene flow between the two species. To further probe how gene flow influences the effect HGT has on mobile gene evolution, I tested how varying the HGT rate with the CRM (effectively allowing us to control the amount of gene flow) affects mobile gene fitness outcomes. I used the same host landscape pairs used in our pilot study while varying the HGT rate along a biologically relevant range. I expect to find a positive correlation between HGT rate and the magnitude of positive fitness effects conferred by a mobile gene that has undergone HGT.