Academic Journal

Dissolved gases in the deep North Atlantic track ocean ventilation processes

التفاصيل البيبلوغرافية
العنوان: Dissolved gases in the deep North Atlantic track ocean ventilation processes
المؤلفون: Seltzer, Alan M., Nicholson, David P., Smethie, William M., Tyne, Rebecca L., Le Roy, Emilie, Stanley, Rachel H. R., Stute, Martin, Barry, Peter H., McPaul, Katelyn, Davidson, Perrin W., Chang, Bonnie X., Rafter, Patrick A., Lethaby, Paul, Johnson, Rod J., Khatiwala, Samar, Jenkins, William J.
سنة النشر: 2023
المجموعة: GEO-LEOe-docs (SUB Göttingen / TU Bergakademie Freiberg)
مصطلحات موضوعية: ddc:551, gas exchange, nitrogen cycle, overturning circulation, air-sea interaction, noble gases
الوصف: Gas exchange between the atmosphere and ocean interior profoundly impacts global climate and biogeochemistry. However, our understanding of the relevant physical processes remains limited by a scarcity of direct observations. Dissolved noble gases in the deep ocean are powerful tracers of physical air-sea interaction due to their chemical and biological inertness, yet their isotope ratios have remained underexplored. Here, we present high-precision noble gas isotope and elemental ratios from the deep North Atlantic (~32°N, 64°W) to evaluate gas exchange parameterizations using an ocean circulation model. The unprecedented precision of these data reveal deep-ocean undersaturation of heavy noble gases and isotopes resulting from cooling-driven air-to-sea gas transport associated with deep convection in the northern high lati-tudes. Our data also imply an underappreciated and large role for bubble-mediated gas exchange in the global air-sea transfer of sparingly soluble gases, including O2, N2, and SF6. Using noble gases to validate the physical representation of air-sea gas exchange in a model also provides a unique opportunity to distinguish physical from biogeochemical signals. As a case study, we compare dissolved N2/Ar measurements in the deep North Atlantic to physics-only model predictions, revealing excess N2 from benthic denitrification in older deep waters (below 2.9 km). These data indicate that the rate of fixed N removal in the deep Northeastern Atlantic is at least three times higher than the global deep-ocean mean, suggesting tight coupling with organic carbon export and raising potential future implications for the marine N cycle. ; NSF, UK NERC, University of Oxford Advanced Research Computing facility ; https://www.bco-dmo.org/project/887496 ; research
نوع الوثيقة: article in journal/newspaper
اللغة: English
تدمد: 0027-8424
Relation: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/10525
DOI: 10.1073/pnas.2217946120
الاتاحة: https://doi.org/10.1073/pnas.2217946120
http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/10525
Rights: CC::CC BY-ND-NC 4.0
رقم الانضمام: edsbas.EBB2A3C3
قاعدة البيانات: BASE
الوصف
تدمد:00278424
DOI:10.1073/pnas.2217946120