Tag: Homepage_Publication

Interannual Variability of the South Atlantic Ocean Heat Content in a High‐Resolution Versus a Low‐Resolution General Circulation Model

Gronholz, A., Dong, S., Lopez, H., Lee, S. K., Goni, G., & Baringer, M. (2020). Interannual variability of the South Atlantic Ocean heat content in a high‐resolution versus a low‐resolution General Circulation Model. Geophysical Research Letters, e2020GL089908.

Plain Language Summary: In this study we analyze heat content changes of the upper South Atlantic Ocean and the impact of model resolution on these changes. Results from two numerical simulations are compared. One simulation with high‐resolution allows smaller‐scale processes directly, while the other simulation with low‐resolution does not. In both simulations oceanic heat transport dominates the ocean heat content changes on interannual time scale, while atmospheric fluxes play a secondary role. The heat anomalies, however, originate from different regions in the two simulations. While the oceanic heat transport from the south dominates in the high‐resolution simulation, oceanic heat transport from the north dominates in the low‐resolution simulation. Furthermore, wind‐induced surface heat transport plays a significant role in the low‐resolution while the heat transport in the high‐resolution simulation is dominated by…

Read Full Paper.

Read More

Subsurface Automated Samplers (SAS) for Ocean Acidification Research

ENOCHS, I.C., N. FORMEL, L. SHEA, L. CHOMIAK, A. Piggot, A. KIRKLAND, and D. MANZELLO. Subsurface automated samplers (SAS) for ocean acidification research. Bulletin of Marine Science, 96(4):735-752 (https://doi.org/10.5343/bms.2020.0018) (2020).

Abstract: Ocean acidification (OA) is the process whereby anthropogenic carbon dioxide is absorbed into seawater, resulting in altered carbonate chemistry and a decline in pH. OA will negatively impact numerous marine organisms, altering the structure and function of entire ecosystems. The progression of OA, while faster than has occurred in recent geological history, has been subtle and detection may be complicated by high variability in shallow-water environments. Nevertheless, comprehensive monitoring and characterization is important given the scale and severity of the problem. Presently, technologies used to measure OA in the field are costly and limited by their detection of only one carbonate chemistry parameter, such as pH. Discrete water samples, by contrast, offer a means of measuring multiple components of the carbonate system, including parameters of particular explanatory value (e.g., total alkalinity, dissolved inorganic carbon), for which field-based sensors do not presently exist…

Read Full Article

Read More

The Oceanic Sink for Anthropogenic CO2 from 1994 to 2007

Gruber, N., Clement, D., Carter, B. R., Feely, R. A., van Heuven, S., Hoppema, M., … & Monaco, C. L. (2019). The oceanic sink for anthropogenic CO2 from 1994 to 2007. Science, 363(6432), 1193-1199.

Abstract:

We quantify the oceanic sink for anthropogenic carbon dioxide (CO2) over the period 1994 to 2007 by using observations from the global repeat hydrography program and contrasting them to observations from the 1990s. Using a linear regression–based method, we find a global increase in the anthropogenic CO2 inventory of 34 ± 4 petagrams of carbon (Pg C) between 1994 and 2007. This is equivalent to an average uptake rate of 2.6 ± 0.3 Pg C year−1 and represents 31 ± 4% of the global anthropogenic CO2 emissions over this period. Although this global ocean sink estimate is consistent with the expectation of the ocean uptake having increased in proportion to the rise in atmospheric CO2, substantial regional differences in storage rate are found, likely owing to climate variability–driven changes in ocean circulation.

View PDF Article or read the NOAA Post.

Read More