Articles | Volume 22, issue 5
https://doi.org/10.5194/os-22-2711-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-22-2711-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Sep 2026
Research article |
| 08 Sep 2026
| 08 Sep 2026
Seasonal stratification regulates carbon allocation between particulate and dissolved pathways in the Gulf of Aqaba
Eyal Rahav
CORRESPONDING AUTHOR
Israel Oceanographic and Limnological Research, Haifa, Israel
Institute of Marine Science, University of California, Santa Cruz, CA, USA
Department of Earth and Environmental Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
Adina Paytan
Institute of Marine Science, University of California, Santa Cruz, CA, USA
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Microbes in the sunlit waters of the nitrogen-poor northern Red Sea transform ammonia into other forms of nitrogen, a process once thought to be almost absent in surface waters. We found that this activity does occur, but at very low rates. Additionally, these microbes contribute only a small share to carbon production, yet they recycle nitrogen and influence how scientists estimate ocean productivity in a warming world.
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Maxim Rubin-Blum, Eyal Rahav, Guy Sisma-Ventura, Yana Yudkovski, Zoya Harbuzov, Or M. Bialik, Oded Ezra, Anneleen Foubert, Barak Herut, and Yizhaq Makovsky
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Aerosol particles can interact with incoming solar radiation and outgoing long wave radiation, change cloud properties, affect photochemistry, impact surface air quality, and when deposited impact surface albedo of snow and ice, and modulate carbon dioxide uptake by the land and ocean. Here we present a new compilation of aerosol observations including composition, a methodology for comparing the datasets to model output, and show the implications of these results using one model.
Zhibo Shao, Yangchun Xu, Hua Wang, Weicheng Luo, Lice Wang, Yuhong Huang, Nona Sheila R. Agawin, Ayaz Ahmed, Mar Benavides, Mikkel Bentzon-Tilia, Ilana Berman-Frank, Hugo Berthelot, Isabelle C. Biegala, Mariana B. Bif, Antonio Bode, Sophie Bonnet, Deborah A. Bronk, Mark V. Brown, Lisa Campbell, Douglas G. Capone, Edward J. Carpenter, Nicolas Cassar, Bonnie X. Chang, Dreux Chappell, Yuh-ling Lee Chen, Matthew J. Church, Francisco M. Cornejo-Castillo, Amália Maria Sacilotto Detoni, Scott C. Doney, Cecile Dupouy, Marta Estrada, Camila Fernandez, Bieito Fernández-Castro, Debany Fonseca-Batista, Rachel A. Foster, Ken Furuya, Nicole Garcia, Kanji Goto, Jesús Gago, Mary R. Gradoville, M. Robert Hamersley, Britt A. Henke, Cora Hörstmann, Amal Jayakumar, Zhibing Jiang, Shuh-Ji Kao, David M. Karl, Leila R. Kittu, Angela N. Knapp, Sanjeev Kumar, Julie LaRoche, Hongbin Liu, Jiaxing Liu, Caroline Lory, Carolin R. Löscher, Emilio Marañón, Lauren F. Messer, Matthew M. Mills, Wiebke Mohr, Pia H. Moisander, Claire Mahaffey, Robert Moore, Beatriz Mouriño-Carballido, Margaret R. Mulholland, Shin-ichiro Nakaoka, Joseph A. Needoba, Eric J. Raes, Eyal Rahav, Teodoro Ramírez-Cárdenas, Christian Furbo Reeder, Lasse Riemann, Virginie Riou, Julie C. Robidart, Vedula V. S. S. Sarma, Takuya Sato, Himanshu Saxena, Corday Selden, Justin R. Seymour, Dalin Shi, Takuhei Shiozaki, Arvind Singh, Rachel E. Sipler, Jun Sun, Koji Suzuki, Kazutaka Takahashi, Yehui Tan, Weiyi Tang, Jean-Éric Tremblay, Kendra Turk-Kubo, Zuozhu Wen, Angelicque E. White, Samuel T. Wilson, Takashi Yoshida, Jonathan P. Zehr, Run Zhang, Yao Zhang, and Ya-Wei Luo
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Short summary
Short summary
N2 fixation by marine diazotrophs is an important bioavailable N source to the global ocean. This updated global oceanic diazotroph database increases the number of in situ measurements of N2 fixation rates, diazotrophic cell abundances, and nifH gene copy abundances by 184 %, 86 %, and 809 %, respectively. Using the updated database, the global marine N2 fixation rate is estimated at 223 ± 30 Tg N yr−1, which triplicates that using the original database.
Daniel François, Adina Paytan, Olga Maria Oliveira de Araújo, Ricardo Tadeu Lopes, and Cátia Fernandes Barbosa
Biogeosciences, 19, 5269–5285, https://doi.org/10.5194/bg-19-5269-2022, https://doi.org/10.5194/bg-19-5269-2022, 2022
Short summary
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Our analysis revealed that under the two most conservative acidification projections foraminifera assemblages did not display considerable changes. However, a significant decrease in species richness was observed when pH decreases to 7.7 pH units, indicating adverse effects under high-acidification scenarios. A micro-CT analysis revealed that calcified tests of Archaias angulatus were of lower density in low pH, suggesting no acclimation capacity for this species.
Natalia Belkin, Tamar Guy-Haim, Maxim Rubin-Blum, Ayah Lazar, Guy Sisma-Ventura, Rainer Kiko, Arseniy R. Morov, Tal Ozer, Isaac Gertman, Barak Herut, and Eyal Rahav
Ocean Sci., 18, 693–715, https://doi.org/10.5194/os-18-693-2022, https://doi.org/10.5194/os-18-693-2022, 2022
Short summary
Short summary
We studied how distinct water circulations that elevate (cyclone) or descend (anticyclone) water from the upper ocean affect the biomass, activity and diversity of planktonic microorganisms in the impoverished eastern Mediterranean. We show that cyclonic and anticyclonic eddies differ in their community composition and production. Moreover, the anticyclone may be a potential bio-invasion and dispersal vector, while the cyclone may serve as a thermal refugee for native species.
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Short summary
To understand how ocean warming may alter carbon storage, we examined seasonal carbon cycling in the northern Red Sea over five months. As summer warming intensified water-column stratification and reduced nutrient supply, carbon fixation by microscopic algae declined, while a larger fraction of newly produced carbon was released as dissolved material and rapidly respired by bacteria. This near-surface recycling may reduce carbon transfer to depth and weaken ocean carbon storage.
To understand how ocean warming may alter carbon storage, we examined seasonal carbon cycling in...
