Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region
Ocean isotopic evaporation models, such as the Craig‐Gordon model, rely on the description of nonequilibrium fractionation factors that are, in general, poorly constrained. To date, only a few gradient‐diffusion type measurements have been performed in ocean settings to test the validity of the comm...
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ftpubmed:oai:pubmedcentral.nih.gov:9786641 2023-05-15T17:40:23+02:00 Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region Zannoni, D. Steen‐Larsen, H. C. Peters, A. J. Wahl, S. Sodemann, H. Sveinbjörnsdóttir, A. E. 2022-11-08 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9786641/ https://doi.org/10.1029/2022JD037076 en eng John Wiley and Sons Inc. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9786641/ http://dx.doi.org/10.1029/2022JD037076 © 2022. The Authors. https://creativecommons.org/licenses/by/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. CC-BY J Geophys Res Atmos Research Article Text 2022 ftpubmed https://doi.org/10.1029/2022JD037076 2023-01-01T01:33:29Z Ocean isotopic evaporation models, such as the Craig‐Gordon model, rely on the description of nonequilibrium fractionation factors that are, in general, poorly constrained. To date, only a few gradient‐diffusion type measurements have been performed in ocean settings to test the validity of the commonly used parametrization of nonequilibrium isotopic fractionation during ocean evaporation. In this work, we present 6 months of water vapor isotopic observations collected from a meteorological tower located in the northwest Atlantic Ocean (Bermuda) with the objective of estimating nonequilibrium fractionation factors (k, ‰) for ocean evaporation and their wind speed dependency. The Keeling Plot method and Craig‐Gordon model combination were sensitive enough to resolve nonequilibrium fractionation factors during evaporation resulting into mean values of k (18) = 5.2 ± 0.6‰ and k (2) = 4.3 ± 3.4‰. Furthermore, we evaluate the relationship between k and 10‐m wind speed over the ocean. Such a relationship is expected from current evaporation theory and from laboratory experiments made in the 1970s, but observational evidence is lacking. We show that (a) in the observed wind speed range [0–10 m s(−1)], the sensitivity of k to wind speed is small, in the order of −0.2‰ m(−1) s for k (18), and (b) there is no empirical evidence for the presence of a discontinuity between smooth and rough wind speed regime during isotopic fractionation, as proposed in earlier studies. The water vapor d‐excess variability predicted under the closure assumption using the k values estimated in this study is in agreement with observations over the Atlantic Ocean. Text North West Atlantic Northwest Atlantic PubMed Central (PMC) Journal of Geophysical Research: Atmospheres 127 21 |
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Research Article Zannoni, D. Steen‐Larsen, H. C. Peters, A. J. Wahl, S. Sodemann, H. Sveinbjörnsdóttir, A. E. Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
topic_facet |
Research Article |
description |
Ocean isotopic evaporation models, such as the Craig‐Gordon model, rely on the description of nonequilibrium fractionation factors that are, in general, poorly constrained. To date, only a few gradient‐diffusion type measurements have been performed in ocean settings to test the validity of the commonly used parametrization of nonequilibrium isotopic fractionation during ocean evaporation. In this work, we present 6 months of water vapor isotopic observations collected from a meteorological tower located in the northwest Atlantic Ocean (Bermuda) with the objective of estimating nonequilibrium fractionation factors (k, ‰) for ocean evaporation and their wind speed dependency. The Keeling Plot method and Craig‐Gordon model combination were sensitive enough to resolve nonequilibrium fractionation factors during evaporation resulting into mean values of k (18) = 5.2 ± 0.6‰ and k (2) = 4.3 ± 3.4‰. Furthermore, we evaluate the relationship between k and 10‐m wind speed over the ocean. Such a relationship is expected from current evaporation theory and from laboratory experiments made in the 1970s, but observational evidence is lacking. We show that (a) in the observed wind speed range [0–10 m s(−1)], the sensitivity of k to wind speed is small, in the order of −0.2‰ m(−1) s for k (18), and (b) there is no empirical evidence for the presence of a discontinuity between smooth and rough wind speed regime during isotopic fractionation, as proposed in earlier studies. The water vapor d‐excess variability predicted under the closure assumption using the k values estimated in this study is in agreement with observations over the Atlantic Ocean. |
format |
Text |
author |
Zannoni, D. Steen‐Larsen, H. C. Peters, A. J. Wahl, S. Sodemann, H. Sveinbjörnsdóttir, A. E. |
author_facet |
Zannoni, D. Steen‐Larsen, H. C. Peters, A. J. Wahl, S. Sodemann, H. Sveinbjörnsdóttir, A. E. |
author_sort |
Zannoni, D. |
title |
Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
title_short |
Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
title_full |
Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
title_fullStr |
Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
title_full_unstemmed |
Non‐Equilibrium Fractionation Factors for D/H and (18)O/(16)O During Oceanic Evaporation in the North‐West Atlantic Region |
title_sort |
non‐equilibrium fractionation factors for d/h and (18)o/(16)o during oceanic evaporation in the north‐west atlantic region |
publisher |
John Wiley and Sons Inc. |
publishDate |
2022 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9786641/ https://doi.org/10.1029/2022JD037076 |
genre |
North West Atlantic Northwest Atlantic |
genre_facet |
North West Atlantic Northwest Atlantic |
op_source |
J Geophys Res Atmos |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9786641/ http://dx.doi.org/10.1029/2022JD037076 |
op_rights |
© 2022. The Authors. https://creativecommons.org/licenses/by/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2022JD037076 |
container_title |
Journal of Geophysical Research: Atmospheres |
container_volume |
127 |
container_issue |
21 |
_version_ |
1766141292265340928 |