Research Projects
Impacts of Eddy Coherency on Chlorophyll-a Concentration
In this remote sensing project, we use a Lagrangian perspective to re-examine the idealized assumption that mesoscale eddies are laterally coherent with the ability to trap and transport phytoplankton populations. We find that the trapping strengths of features in a subtropical gyre evolve over their lifetimes, and only half are strictly Lagrangian coherent at any given time. This effects the concentration of phytoplankton observed in eddies, where trapping locally elevates patches of chlorophyll concentration more so than their leaky counterparts. Nevertheless, leaky eddies also alter chlorophyll concentrations and their contribution to primary productivity may be underestimated because these biological responses are not preserved for long timescales.Publications:
- Jones-Kellett AE & Follows MJ (2024). A Lagrangian Coherent Eddy Atlas for Biogeochemical Applications in the North Pacific Subtropical Gyre. Earth System Science Data, 16, 1475-1501. doi.org/10.5194/essd-16-1475-2024
- Jones-Kellett AE & Follows MJ (Preprint). The satellite chlorophyll signature of Lagrangian eddy trapping varies regionally and seasonally within a subtropical gyre. Under Review with Ocean Science. doi.org/10.5194/egusphere-2024-3211
Mesoscale Phytoplankton Variability in the Eastern North Pacific
I went on the SCOPE Gradients 4 Cruise in November and December of 2021 where I led a sampling campaign to filter surface seawater samples at 46-km intervals along a cruise transect spanning the southern California Current System and the oligotrophic North Pacific Subtropical Gyre. During the DNA extraction process, I spiked the samples with genomic standards which enabled evaluation of the absolute volumetric gene copy abundances of 16S and 18S rRNA amplicon sequence variants (amplified with 515Y-926R universal primers). We found that this method yielded remarkable agreement of picocyanobacteria cell abundances, as validated with analogous flow cytometry measurements. A publication is in preparation evaluating how mesoscale currents shape phytoplankton variability along this cruise transect.Publications:
- Jones-Kellett AE, McNichol JC, Raut Y, Cain KR, Ribalet F, Armbrust EV, Follows MJ, Fuhrman JA (2024). Amplicon sequencing with internal standards yields accurate picocyanobacteria cell abundances as validated with flow cytometry. ISME Communications, 4(1): ycae115. doi.org/10.1093/ismeco/ycae115
- Jones-Kellett AE, McNichol JC, Raut Y, Fuhrman JA, Follows MJ. Lagrangian histories explain mesoscale phytoplankton variability in the North Pacific Subtropical Gyre. In preparation.
Air-Sea Exchange of Carbon in Eddies
The Surface Ocean CO2 ATlas (SOCAT) project has 35.6 million observations of carbon dioxide in the ocean as of 2022. With this open-source dataset, it is now possible to investigate fluctations in the air-sea exchange of carbon in smaller ocean features such as eddies. I worked on this project primarily as a mentor to MIT undergraduate Sydney Kim and MIT Masters' student Christine Padalino. Christine was co-advised by Drs. Greg Britten (WHOI), Mick Follows (MIT), and I. She defended her thesis in April 2023, entitled "The effect of eddies on fCO2 in the North Pacific surface ocean". We are currently working on a manuscript describing and extending the results of Christine's thesis.
Biogeochemical Argo Floats in the Lofoten Basin Eddy
Argo floats equipped with biogeochemical sensors (BGC-Argo) continuously take measurements of optical properties throughout the water column. While eddies are commonly studied from the surface by satellites, BGC-Argo provides a unique insight into processes happening at depth. This project focuses on BGC-Argo floats in and around the Lofoten Basin Eddy, a semi-permanent anticyclone located off of the coast of Norway. A manuscript led by Daniel Kostner is in under review, examining the seasonal cycle of particulate organic carbon (POC) in the eddy compared to surrounding waters.Publications:
- Koestner D, Clayton S, Lerner P, Jones-Kellett AE, Walker SL. Biogeochemical-Argo floats reveal seasonality of the biological carbon pump influenced by the Lofoten Basin Eddy. Under Review with Geophysical Research Letters.
Page last updated: Nov 26, 2024