Easley
Regina A.
Easley
Regina A.
No Thumbnail Available
2 results
Search Results
Now showing
1 - 2 of 2
-
ArticleStorm-induced upwelling of high pCO2 waters onto the continental shelf of the western Arctic Ocean and implications for carbonate mineral saturation states(American Geophysical Union, 2012-04-11) Mathis, Jeremy T. ; Pickart, Robert S. ; Byrne, Robert H. ; McNeil, Craig L. ; Moore, G. W. K. ; Juranek, Laurie W. ; Liu, Xuewu ; Ma, Jian ; Easley, Regina A. ; Elliot, Matthew M. ; Cross, Jessica N. ; Reisdorph, Stacey C. ; Bahr, Frank B. ; Morison, James H. ; Lichendorf, Trina ; Feely, Richard A.The carbon system of the western Arctic Ocean is undergoing a rapid transition as sea ice extent and thickness decline. These processes are dynamically forcing the region, with unknown consequences for CO2 fluxes and carbonate mineral saturation states, particularly in the coastal regions where sensitive ecosystems are already under threat from multiple stressors. In October 2011, persistent wind-driven upwelling occurred in open water along the continental shelf of the Beaufort Sea in the western Arctic Ocean. During this time, cold (<−1.2°C), salty (>32.4) halocline water—supersaturated with respect to atmospheric CO2 (pCO2 > 550 μatm) and undersaturated in aragonite (Ωaragonite < 1.0) was transported onto the Beaufort shelf. A single 10-day event led to the outgassing of 0.18–0.54 Tg-C and caused aragonite undersaturations throughout the water column over the shelf. If we assume a conservative estimate of four such upwelling events each year, then the annual flux to the atmosphere would be 0.72–2.16 Tg-C, which is approximately the total annual sink of CO2 in the Beaufort Sea from primary production. Although a natural process, these upwelling events have likely been exacerbated in recent years by declining sea ice cover and changing atmospheric conditions in the region, and could have significant impacts on regional carbon budgets. As sea ice retreat continues and storms increase in frequency and intensity, further outgassing events and the expansion of waters that are undersaturated in carbonate minerals over the shelf are probable.
-
ArticleUncertainty sources for measurable ocean carbonate chemistry variables(Association for the Sciences of Limnology and Oceanography (ASLO), 2023-12-14) Carter, Brendan R. ; Sharp, Jonathan D. ; Dickson, Andrew G. ; Alvarez, Marta ; Fong, Michael B. ; Garcia-Ibanez, Maribel I. ; Woosley, Ryan J. ; Takeshita, Yuichiro ; Barbero, Leticia ; Byrne, Robert H. ; Cai, Wei-Jun ; Chierici, Melissa ; Clegg, Simon L. ; Easley, Regina A. ; Fassbender, Andrea J. ; Fleger, Kalla L. ; Li, Xinyu ; Martin-Mayor, Macarena ; Schockman, Katelyn M. ; Wang, Zhaohui AleckThe ocean carbonate system is critical to monitor because it plays a major role in regulating Earth's climate and marine ecosystems. It is monitored using a variety of measurements, and it is commonly understood that all components of seawater carbonate chemistry can be calculated when at least two carbonate system variables are measured. However, several recent studies have highlighted systematic discrepancies between calculated and directly measured carbonate chemistry variables and these discrepancies have large implications for efforts to measure and quantify the changing ocean carbon cycle. Given this, the Ocean Carbonate System Intercomparison Forum (OCSIF) was formed as a working group through the Ocean Carbon and Biogeochemistry program to coordinate and recommend research to quantify and/or reduce uncertainties and disagreements in measurable seawater carbonate system measurements and calculations, identify unknown or overlooked sources of these uncertainties, and provide recommendations for making progress on community efforts despite these uncertainties. With this paper we aim to (1) summarize recent progress toward quantifying and reducing carbonate system uncertainties; (2) advocate for research to further reduce and better quantify carbonate system measurement uncertainties; (3) present a small amount of new data, metadata, and analysis related to uncertainties in carbonate system measurements; and (4) restate and explain the rationales behind several OCSIF recommendations. We focus on open ocean carbonate chemistry, and caution that the considerations we discuss become further complicated in coastal, estuarine, and sedimentary environments.