Award: OCE-1357375

The main focus of this research was the examination of atmospheric aerosol chemistry. Aerosols are micron sized particles that are carried by winds all over the earth. In many ocean regions aerosols are a significant source of limited nutrient elements that algae in the ocean need to grow. Without the inputs of nutrients from aerosols, algae production becomes very limited. Algae are at the base of the food chain in the ocean and the growth of every larger organism in the ocean, such as fish, ultimately depends on the production of algae. The most significant findings of this research activity show that chemical transformations occurring during aerosol transport can greatly increase the solubility and thus potential bioavailability of nutrients like phosphorus and iron in aerosols. Overall these transformations are related to a number of factors including reactions that produce acid on aerosol surfaces, transport time, levels of anthropogenic contribution to an air mass and source region composition. As part of this research, we developed new methods using a tool called a synchrotron. These are instruments, located at US national laboratory facilities, that produce very powerful X-ray beams. These X-ray beams allow us to analyze the chemical composition and mineralogy of very small particles like aerosols. New synchrotron based analytical approaches and techniques for synchrotron data processing have been a key activity of this research. A secondary activity of this grant was the development of techniques to extract and analyze marine dissolved organic matter. Marine dissolved organic matter plays a role in atmospheric aerosol formation and it may be a source of ligands to aerosols that promote phosphorus and iron solubility. Beyond the scientific achievements of this research, the principal investigator has spent approximately 250 contact hours working with Elementary, Middle and Elementary School teachers to enrich Science education. The investigator worked with teachers every year over the three years of this grant. A typical year included 5 full day sessions on weekends throughout the school year as well as intensive summer activities (10 full day sessions during the summer). Numerous engaging, hands on exercises as well as field trips have been developed with the aim of giving teachers better resources to more effectively teach science in Georgia. Last Modified: 01/23/2019 Submitted by: Ellery D Ingall