The School of Marine Sciences presents
Dr. Joseph Salisbury
University of New Hampshire
A profound warming event in the Gulf of Maine (GOM) during the last decade has caused sea surface temperatures (SST) to rise to levels 2 solubility and, in turn, the status of the sea surface carbonate system. When combined with the concomitant increase in sea surface salinity and assumed rapid equilibration of carbon dioxide across the air sea interface, thermodynamic forcing partially mitigated the effects of ocean acidification (OA) for pH, while raising the saturation index of aragonite (WAR) by an average of 0.14 units. Although the recent event is categorically extreme, we find that carbonate system parameters also respond to interannual to sub-‐decadal variability in temperature and salinity, and that such phenomena can mask the expression of OA caused by increasing atmospheric carbon dioxide. An analysis of a 34-‐year salinity and SST time series (1981-‐2014) shows instances of decadal scale anomalies in temperature and salinity that perturb the carbonate system to an extent greater than that expected from OA. Because such conditions are not uncommon in our time series, it is critical to understand processes controlling the carbonate system and how ecosystems with calcifying organisms respond to its rapidly changing conditions. It is also imperative that regional to global models used to estimate carbonate system trends carefully resolve variations in the physical processes that control CO2 on timescales from episodic events to decades and longer.
Polycom availability with Darling Marine Center, Gulf of Maine Research Institute, and Bigelow Laboratories
Host: Damian Brady (damian.brady@maine.edu)