|High-Resolution Underway O2/Ar Records - What are they telling us?|
Dennis McGillicuddy (WHOI) Raf Ferrari (MIT)
In this project, we are exploring kilometer-scale records of O2/Ar -- and therefore by extension of Net Community Production (NCP). This project has two parts. In the first part, in collaboration with Prof. Raf Ferrari, I am examining the statistical variability in submesoscale records of NCP and comparing it to the statistical variability in physical forcing, such as temperature. We have found, that at least to scales down to 10 km, the statistical variability in O2/Ar is very similar to that in temperature, suggesting that there is no "extra variability" in biology. Rather biology has the same variability as the physics. In the second part, in collaboration with Dr. Dennis McGillicuddy (WHOI), I am looking at the spatial variability in NCP and also the causes for that variability. My group participated in a cruise led by Dennis McGillicuddy in which we used an underway O2/Ar mass spectrometer and also added oxygen sensors to the video plankton recorder (VPR-II) - a towed instrument that undulates in the upper 100 m of the water column. We thus are able to compare the variability we see in the surface O2/Ar to the oxygen records from below the mixed layer to see if changes in mixed layer O2/Ar are a result of biological productivity or if they are simply a result of injection of water below the mixed layer. Additionally, we crossed several eddy features and will be examining the response of NCP and gross primary production (as measured by triple oxygen isotopes) to the eddies. This project is funded by the National Science Foundation.