| NSF Org: |
OCE Division Of Ocean Sciences |
| Recipient: |
|
| Initial Amendment Date: | June 10, 2024 |
| Latest Amendment Date: | June 10, 2024 |
| Award Number: | 2343386 |
| Award Instrument: | Standard Grant |
| Program Manager: |
Henrietta Edmonds
hedmonds@nsf.gov (703)292-7427 OCE Division Of Ocean Sciences GEO Directorate for Geosciences |
| Start Date: | June 15, 2024 |
| End Date: | May 31, 2027 (Estimated) |
| Total Intended Award Amount: | $367,399.00 |
| Total Awarded Amount to Date: | $367,399.00 |
| Funds Obligated to Date: |
|
| History of Investigator: |
|
| Recipient Sponsored Research Office: |
310 E CAMPUS RD RM 409 ATHENS GA US 30602-1589 (706)542-5939 |
| Sponsor Congressional District: |
|
| Primary Place of Performance: |
310 EAST CAMPUS RD TUCKER HALL ROOM 409 ATHENS GA US 30602-1589 |
| Primary Place of
Performance Congressional District: |
|
| Unique Entity Identifier (UEI): |
|
| Parent UEI: |
|
| NSF Program(s): |
Atmospheric Chemistry, Chemical Oceanography |
| Primary Program Source: |
|
| Program Reference Code(s): |
|
| Program Element Code(s): |
|
| Award Agency Code: | 4900 |
| Fund Agency Code: | 4900 |
| Assistance Listing Number(s): | 47.050 |
ABSTRACT
Many trace elements (TEs) such as iron are required for the growth of phytoplankton in the ocean, and their availability can limit biological production. One important pathway by which these scarce elements are delivered to surface ocean waters is through aerosol particles in the atmosphere. This project will address important questions about the variability in the atmospheric delivery of iron and other TEs to the surface waters of the North Atlantic Ocean near Bermuda through aerosol sampling, laboratory experiments, and modeling. Increased accuracy of atmospheric deposition and aerosol iron solubility representation will improve global biogeochemical models and our understanding of how changes in climate may influence the marine carbon cycle through changes in atmospheric iron deposition. The project will provide opportunities for undergraduate and graduate student involvement and support an early-career scientist. Data will be posted on the BCO-DMO website and made widely available to scientists working in similar fields by being included in the SCOR Working Group 167 (Reducing Uncertainty in Soluble aerosol Trace Element Deposition) data compilation.
This project will conduct a two-year time-series of size-fractionated aerosol sampling at the Tudor Hill Marine Atmospheric Observatory in Bermuda to accomplish four goals:
1. Analyze temporal variations in the size distribution of aerosol Fe and other bioactive, pollutant, and tracer TEs, as well as major cations and anions over the western North Atlantic Ocean and link these variations to aerosol sources and transport pathways.
2. Apply a range of chemical extractions to size-fractionated and bulk North Atlantic aerosols to quantify lower and upper estimates of potentially bioavailable Fe and explain trends in bulk aerosol Fe solubility in the context of variations observed in size-fractionated aerosols.
3. Use elemental ratios, Fe stable isotopes, Fe-mineralogical partitioning and redox state, and air mass back trajectories to directly probe the chemical controls on aerosol Fe solubility as a function of aerosol particle size and source over a two-year period.
4. Parameterize concurrently measured meteorological conditions to model deposition velocities for each aerosol size-fraction during weekly sampling periods, thereby constraining supply rates of total and soluble TEs to North Atlantic surface waters.
The results of this study will provide a deeper understanding of the factors influencing trace element solubility in North Atlantic aerosols and the role that aerosol size distribution plays in these variations. Rates of dry deposition calculated using size-fractionated aerosol collections will give a better understanding of the potential overestimation of bioavailable trace element supply rate that may arise from previous calculations based solely on bulk aerosol concentrations. This project will thus improve representation of atmospheric trace element solubility and deposition flux in global and regional deposition models.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Please report errors in award information by writing to: awardsearch@nsf.gov.
