Articles | Volume 23, issue 16
https://doi.org/10.5194/bg-23-5625-2026
© 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/bg-23-5625-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Aug 2026
Research article |
| 17 Aug 2026
| 17 Aug 2026
The impact of NaOH, CaO, and [Ca2+] + [HCO3−] additions on PIC and POC formation in Los Angeles Harbor Waters
Department of Earth Sciences, University of Southern California, Los Angeles, 90089, United States
Devan L. Roper
Department of Earth Sciences, University of Southern California, Los Angeles, 90089, United States
Ria Agrawal
Rosenstiel School of Marine, Atmospheric & Earth Science, University of Miami, Miami, 33149, United States
Esther J. Lim
Department of Earth Sciences, University of Southern California, Los Angeles, 90089, United States
Nick E. Rollins
Department of Earth Sciences, University of Southern California, Los Angeles, 90089, United States
William M. Berelson
Department of Earth Sciences, University of Southern California, Los Angeles, 90089, United States
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Sujan Shrestha, Robert E. Holz, Willem J. Marais, Zachary Buckholtz, Ilya Razenkov, Edwin Eloranta, Jeffrey S. Reid, Hope E. Elliott, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Edmund Blades, Albert D. Ortiz, Rebecca Chewitt-Lucas, Alyson Allen, Devon Blades, Ria Agrawal, Elizabeth A. Reid, Jesus Ruiz-Plancarte, Anthony Bucholtz, Ryan Yamaguchi, Qing Wang, Thomas Eck, Elena Lind, Mira L. Pöhlker, Andrew P. Ault, and Cassandra J. Gaston
Atmos. Chem. Phys., 26, 983–999, https://doi.org/10.5194/acp-26-983-2026, https://doi.org/10.5194/acp-26-983-2026, 2026
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Coordinated observations from MAGPIE 2023 show that Saharan dust in the marine atmospheric boundary layer becomes internally mixed with sea spray. This mixing increases particle sphericity and hygroscopicity, likely leading to suppressed lidar linear depolarization ratios despite high dust concentrations. The findings have key implications for interpreting lidar-derived dust retrievals, estimating surface dust from satellite products, and improving dust representation in models.
Milan Y. Patel, Pietro F. Vannucci, Jinsol Kim, William M. Berelson, and Ronald C. Cohen
Atmos. Meas. Tech., 17, 1051–1060, https://doi.org/10.5194/amt-17-1051-2024, https://doi.org/10.5194/amt-17-1051-2024, 2024
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Low-cost particulate matter (PM) sensors are becoming increasingly common in community monitoring and atmospheric research, but these sensors require proper calibration to provide accurate reporting. Here, we propose a hygroscopic growth calibration scheme that evolves in time to account for seasonal changes in hygroscopic growth. In San Francisco and Los Angeles, CA, applying a seasonal hygroscopic growth calibration can account for sensor biases driven by the seasonal cycles in PM composition.
Jinsol Kim, John B. Miller, Charles E. Miller, Scott J. Lehman, Sylvia E. Michel, Vineet Yadav, Nick E. Rollins, and William M. Berelson
Atmos. Chem. Phys., 23, 14425–14436, https://doi.org/10.5194/acp-23-14425-2023, https://doi.org/10.5194/acp-23-14425-2023, 2023
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In this study, we present the partitioning of CO2 signals from biogenic, petroleum and natural gas sources by combining CO, 13CO2 and 14CO2 measurements. Using measurements from flask air samples at three sites in the greater Los Angeles region, we find larger and positive contributions of biogenic signals in winter and smaller and negative contributions in summer. The largest contribution of natural gas combustion generally occurs in summer.
Olivier Sulpis, Matthew P. Humphreys, Monica M. Wilhelmus, Dustin Carroll, William M. Berelson, Dimitris Menemenlis, Jack J. Middelburg, and Jess F. Adkins
Geosci. Model Dev., 15, 2105–2131, https://doi.org/10.5194/gmd-15-2105-2022, https://doi.org/10.5194/gmd-15-2105-2022, 2022
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A quarter of the surface of the Earth is covered by marine sediments rich in calcium carbonates, and their dissolution acts as a giant antacid tablet protecting the ocean against human-made acidification caused by massive CO2 emissions. Here, we present a new model of sediment chemistry that incorporates the latest experimental findings on calcium carbonate dissolution kinetics. This model can be used to predict how marine sediments evolve through time in response to environmental perturbations.
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Short summary
Ocean Alkalinity Enhancement is a climate change mitigation strategy that can reduce the amount of CO2 in our atmosphere. In this study we add three different sources of alkalinity to natural seawater to assess how these chemicals might change carbon partitioning within seawater. The alkalinity we added had little impact on the marine carbon system except that a 4-day exposure to ~1000 µmol kg–1 alkalinity from calcium oxide addition can negatively impact the production of organic matter.
Ocean Alkalinity Enhancement is a climate change mitigation strategy that can reduce the amount...
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