Articles | Volume 25, issue 11
https://doi.org/10.5194/acp-25-5727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-5727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Jun 2025
Research article |
| 11 Jun 2025
| 11 Jun 2025
A 60-year atmospheric nitrate isotope record from a southeastern Greenland ice core with minimal postdepositional alteration
Zhao Wei
International Center for Isotope Effects Research, State Key Laboratory of Critical Earth Material Cycling and Mineral Deposits, Nanjing University, Nanjing 210023, China
International Center for Isotope Effects Research, State Key Laboratory of Critical Earth Material Cycling and Mineral Deposits, Nanjing University, Nanjing 210023, China
Frontiers Science Center for Critical Earth Material Cycling, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Kanagawa 226-8502, Japan
Asuka Tsuruta
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Kanagawa 226-8502, Japan
Zhuang Jiang
National Key Laboratory of Deep Space Exploration, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, Anhui, China
Sakiko Ishino
Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
Koji Fujita
Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601, Japan
Sumito Matoba
Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
National Key Laboratory of Deep Space Exploration, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, Anhui, China
Alexis Lamothe
University Grenoble Alpes, CNRS, IRD, Grenoble INP, INRAE, IGE, 38000 Grenoble, France
Ryu Uemura
Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601, Japan
Naohiro Yoshida
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Kanagawa 226-8502, Japan
National Institute of Information and Communications Technology, Koganei, Tokyo 184-8795, Japan
Earth-Life Science Institute, Institute of Science Tokyo, Tokyo 152-8550, Japan
Joel Savarino
University Grenoble Alpes, CNRS, IRD, Grenoble INP, INRAE, IGE, 38000 Grenoble, France
Aix Marseille University, CNRS, IRD, INRAE, CEREGE, Aix-en-Provence, France
Yoshinori Iizuka
Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
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Alexis Lamothe, Pete Akers, Patrick Ginot, Wendell Walters, Sarah Albertin, Nicolas Caillon, Elsa Gautier, and Joel Savarino
EGUsphere, https://doi.org/10.5194/egusphere-2026-5825, https://doi.org/10.5194/egusphere-2026-5825, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Ammonia pollution has changed greatly during European industrialisation, but how emissions become deposited ammonium remains unclear. We measured nitrogen isotopes of ammonium in a 1,000-year Alpine ice core. The record shows that atmospheric processing changed over time and cannot be explained by emissions alone. Recent decades show a new relationship between emissions and deposition, highlighting major gaps in our understanding of ammonia transport and removal.
Akiko Sakai, Kino Kobayashi, Masato Ono, Sayako Ueda, Sho Ohata, Akira Watanabe, Kazuo Osada, Nozomu Takeuchi, Prevdagva Khalzan, Sumito Matoba, Tomonori Tanikawa, and Teruo Aoki
The Cryosphere, 20, 5181–5198, https://doi.org/10.5194/tc-20-5181-2026, https://doi.org/10.5194/tc-20-5181-2026, 2026
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Glacier ice surfaces appear dark due to many light-absorbing particles (LAPs), such as mineral dust, microbial organic matter, and black carbon. In contrast, the development of a weathering crust on bare ice brightens the surface by increasing albedo. Field studies on the Potanin Glacier, Mongolia, defined a low-density surface layer as weathering granular ice. Broad-band albedo increased with this layer’s thickness but decreased with organic matter. High LAP amounts hindered crust growth.
Adrien Ooms, Mathieu Casado, Sonja Wahl, Thomas Laepple, Alexandra Zuhr, Pete Akers, Ghislain Picard, Laurent Arnaud, Joel Savarino, Kira Rehfeld, Barbara Stenni, Giuliano Dreossi, Mauro Masiol, Amaelle Landais, and Valérie Masson-Delmotte
EGUsphere, https://doi.org/10.5194/egusphere-2026-4801, https://doi.org/10.5194/egusphere-2026-4801, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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This work presents new insights in the archival process of multi-annual climatic signal in the near surface firn at Concordia Station, East-Antarctica, from the new data set of high resolution stable water isotope profiles measured in a snow trench. The dated isotopic profiles covering 20 years are compared against overlapping precipitation and surface snow observations. This highlights the strong contribution of stratigraphic noise and post depositional effects to individual trench profiles.
Mizuki Hirano, Yoshinori Iizuka, Takuto Ando, Kaoru Kawakami, Mai Matsumoto, Yutaka Kurosaki, Hiroshi Ohno, Sumito Matoba, Shoichi Mori, Yosuke Satoh, and Fumiaki Saito
EGUsphere, https://doi.org/10.5194/egusphere-2026-4810, https://doi.org/10.5194/egusphere-2026-4810, 2026
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Boreal wildfires strongly affect global climate. Scientists track past fires using ice cores, but conventional water-soluble markers can move or degrade in ice. We identified oleamide—a water-insoluble compound—in a Greenland ice core (1799–2020) for the first time. Oleamide forms during intense fire heat (300–500 °C) and stays immobilized in ice. Its peaks match major wildfires in 1908, 1961, and 1994, providing a robust new proxy for reconstructing Arctic fire history.
Koji Fujita and Rijan B. Kayastha
The Cryosphere, 20, 4005–4015, https://doi.org/10.5194/tc-20-4005-2026, https://doi.org/10.5194/tc-20-4005-2026, 2026
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Glacier AX010 in Nepal, monitored since the 1970s, has been shrinking at an accelerating rate, mainly due to rising temperatures. Drone surveys, modeling, and reanalysis data show mass loss began in the early 1970s and intensified after 2000. While rising temperatures drive shrinkage, precipitation changes have neither accelerated nor mitigated mass loss. At the current rate, the glacier may disappear within 10–20 years.
Saaya Hamamoto, Yoshinori Iizuka, Takuro Aizawa, Kaoru Kawakami, Mai Matsumoto, Sumito Matoba, Hayoung Bong, Kei Yoshimura, Atsushi Okazaki, Laura Jasmin Dietrich, Hans Christian Steen-Larsen, and Ryu Uemura
EGUsphere, https://doi.org/10.5194/egusphere-2026-3602, https://doi.org/10.5194/egusphere-2026-3602, 2026
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We developed a new 150-year age scale for an ice core from southeast Greenland by matching its oxygen-isotope variations with climate-model simulations. The record resolves changes over several months and shows that snowfall remained nearly evenly distributed through the seasons from 1871 to 2020. This stability suggests that the regional balance of atmospheric circulation and moisture transport changed little at this site despite recent Arctic warming.
Agnese Petteni, Mathieu Casado, Christophe Leroy-Dos Santos, Amaelle Landais, Niels Dutrievoz, Cécile Agosta, Pete D. Akers, Joel Savarino, Andrea Spolaor, Massimo Frezzotti, and Barbara Stenni
The Cryosphere, 20, 3581–3598, https://doi.org/10.5194/tc-20-3581-2026, https://doi.org/10.5194/tc-20-3581-2026, 2026
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We investigated the isotopic composition of surface snow in a previously unexplored region of East Antarctica to understand how differences in air mass origin influence its variability. By comparing observations with model data, we validated the model and quantified the impact of post-depositional processes at the snow–atmosphere interface. Our results offer valuable insights for reconstructing past temperatures from ice cores.
Lison Soussaintjean, Jochen Schmitt, Joël Savarino, J. Andy Menking, Edward J. Brook, Barbara Seth, Vladimir Lipenkov, Thomas Röckmann, and Hubertus Fischer
Biogeosciences, 23, 3939–3963, https://doi.org/10.5194/bg-23-3939-2026, https://doi.org/10.5194/bg-23-3939-2026, 2026
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Nitrous oxide (N2O) produced in dust-rich Antarctic ice complicates the reconstruction of past atmospheric levels from ice core records. Using isotope analysis, we show that N2O forms from two nitrogen precursors, one being nitrate. For the first time, we demonstrate that the site preference (SP) of N2O reflects the isotopic difference between these precursors, not the production pathway, which challenges the common interpretation of SP.
Alexis Lamothe, Edouard Bard, Nicolas Thouveny, Ellyn Auriol, Mirko Severi, Rita Traversi, Martine De Angelis, Frank Wilhelms, Robert Mulvaney, Fawzi Zaidi, Georges Aumaitre, Karim Keddadouche, and Mélanie Baroni
Geochronology, 8, 351–371, https://doi.org/10.5194/gchron-8-351-2026, https://doi.org/10.5194/gchron-8-351-2026, 2026
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We studied changes in Earth's magnetic field between 170 000 and 270 000 years ago using beryllium data from Antarctic ice. Our results reveal three periods when the magnetic field weakened, including one major event with a rapid fall and gradual recovery. These findings help explain how Earth's magnetic field behaves during short-term disturbances and improve the timing of past climate and geological records.
Adrien Ooms, Mathieu Casado, Ghislain Picard, Laurent Arnaud, Maria Hörhold, Andrea Spolaor, Rita Traversi, Joel Savarino, Patrick Ginot, Pete Akers, Birthe Twarloh, and Valérie Masson-Delmotte
The Cryosphere, 20, 3235–3255, https://doi.org/10.5194/tc-20-3235-2026, https://doi.org/10.5194/tc-20-3235-2026, 2026
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This work presents a new approach to the estimation of accumulation rates at Concordia Station, East-Antarctica, for the last 20 years, from a new data set of chemical tracers and snow micro-scale properties measured in a snow trench. Multi-annual and meter to decameter scale variability of accumulation rates are compared again in-situ measurements of surface laser scanner and stake farm, with very good agreement. This further constrains SMB estimation for Antarctica at high temporal resolution.
Ken Kondo and Koji Fujita
Hydrol. Earth Syst. Sci., 30, 1849–1864, https://doi.org/10.5194/hess-30-1849-2026, https://doi.org/10.5194/hess-30-1849-2026, 2026
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Increased runoff due to ice melt in Greenland contributes to sea-level rise and flooding in coastal settlements. We reconstructed glacier runoff in northwestern Greenland in 1950–2023. Long-term modeling shows a recent increase in runoff linked to changes in atmospheric circulation, characterized by enhanced northward transport of heat and moisture. The results highlight a strong influence of atmospheric variability on glacier runoff and its impacts on local communities in northern Greenland.
Francesca Pellicciotti, Adrià Fontrodona-Bach, David R. Rounce, Catriona L. Fyffe, Leif S. Anderson, Álvaro Ayala, Ben W. Brock, Pascal Buri, Stefan Fugger, Koji Fujita, Prateek Gantayat, Alexander R. Groos, Walter Immerzeel, Marin Kneib, Christoph Mayer, Shelley MacDonell, Michael McCarthy, James McPhee, Evan Miles, Heather Purdie, Ekaterina Rets, Akiko Sakai, Thomas E. Shaw, Jakob Steiner, Patrick Wagnon, and Alex Winter-Billington
The Cryosphere, 20, 1895–1928, https://doi.org/10.5194/tc-20-1895-2026, https://doi.org/10.5194/tc-20-1895-2026, 2026
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Rock debris covers many of the world glaciers, modifying the transfer of atmospheric energy to the debris and into the ice. Models of different complexity simulate this process, and we compare 15 models at 9 sites to show that the most complex models at the debris-atmosphere interface have the highest performance. However, we lack debris properties and their derivation from measurements is ambiguous, hindering global modelling and calling for both model development and data collection.
Filip Pastierovič, Roberto Grilli, Nicolas Caillon, and Joel Savarino
Atmos. Meas. Tech., 19, 1943–1950, https://doi.org/10.5194/amt-19-1943-2026, https://doi.org/10.5194/amt-19-1943-2026, 2026
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The development of an open detector based on absorption spectroscopy, enhanced by high-reflectivity mirrors, for the simultaneous measurement of NO2, IO, and CHOCHO is reported. The instrument shows good correlation with a closed system during both indoor and outdoor measurements. An open system is able to measure NO2, IO, and CHOCHO with high precision.
Sayako Ueda, Akiko Sakai, Sho Ohata, Purevdagva Khalzan, Sumito Matoba, Ken Kondo, and Hitoshi Matsui
Atmos. Chem. Phys., 26, 3167–3184, https://doi.org/10.5194/acp-26-3167-2026, https://doi.org/10.5194/acp-26-3167-2026, 2026
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Light-absorbing particles on surface ice in ablation areas can accelerate glacier melting and shrinkage. Snow and ice were collected from the ablation area of Potanin Glacier, Mongolia. The black carbon (BC) mass concentration of surface granular ice was much larger than that of fresh snow and surface melted water, suggesting that BC is retained in the granular ice at melting. The granular ice retained BC particles best in the upstream ablation area, but the capacity decreased in the downstream ablation area.
Yutaka Kurosaki, Sumito Matoba, Mai Matsumoto, Tetsuhide Yamasaki, Ilannguaq Hendriksen, and Yoshinori Iizuka
The Cryosphere, 19, 6171–6186, https://doi.org/10.5194/tc-19-6171-2025, https://doi.org/10.5194/tc-19-6171-2025, 2025
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We conducted snow observations on the coastal region in the northwestern Greenland Ice Sheet close to the North Water. The snowpack on the coastal region in the northwestern Greenland Ice Sheet contained aerosols originated from ocean biological activity and frost flowers in the North Water. The chemical substances in an ice core from the coastal region in the northwestern Greenland Ice Sheet could help explain past changes in ocean biological and sea ice conditions in the North Water.
Orie Sasaki, Evan S. Miles, Francesca Pellicciotti, Akiko Sakai, and Koji Fujita
The Cryosphere, 19, 5283–5298, https://doi.org/10.5194/tc-19-5283-2025, https://doi.org/10.5194/tc-19-5283-2025, 2025
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This study adapts a method to detect snowline altitude (SLA) using Google Earth Engine with high-resolution satellite imagery. Applying this method to five glaciated watersheds in the Himalayas reveals regional consistencies and differences in snow dynamics, as well as 20-year trends of snowline increases (3 catchments) and decreases (1) and no trend (1). We investigate the controls of these dynamics by analyzing climatic factors and topographic characteristics.
Agnese Petteni, Elise Fourré, Elsa Gautier, Azzurra Spagnesi, Roxanne Jacob, Pete D. Akers, Daniele Zannoni, Jacopo Gabrieli, Olivier Jossoud, Frédéric Prié, Amaëlle Landais, Titouan Tcheng, Barbara Stenni, Joel Savarino, Patrick Ginot, and Mathieu Casado
Atmos. Meas. Tech., 18, 5435–5455, https://doi.org/10.5194/amt-18-5435-2025, https://doi.org/10.5194/amt-18-5435-2025, 2025
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Our research compares three systems of continuous flow analysis coupled with cavity ring-down spectrometry (CFA-CRD) from Venice, Paris, and Grenoble laboratories for measuring water isotopes in ice cores, crucial for reconstructing past climate. We quantify each system’s mixing and measurement noise effects, which impact the achievable resolution of isotope continuous records. Our findings reveal specific configurations and procedures to enhance measurement accuracy, providing a framework to optimise water isotope analysis.
Amna Ijaz, Brice Temime-Roussel, Benjamin Chazeau, Sarah Albertin, Stephen R. Arnold, Brice Barret, Slimane Bekki, Natalie Brett, Meeta Cesler-Maloney, Elsa Dieudonne, Kayane K. Dingilian, Javier G. Fochesatto, Jingqiu Mao, Allison Moon, Joel Savarino, William Simpson, Rodney J. Weber, Kathy S. Law, and Barbara D'Anna
Atmos. Chem. Phys., 25, 11789–11811, https://doi.org/10.5194/acp-25-11789-2025, https://doi.org/10.5194/acp-25-11789-2025, 2025
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Fairbanks is among the most polluted cities, with the highest particulate matter (PM) levels in the US during winters. Highly time-resolved measurements of the submicron PM found residential heating with wood and oil and hydrocarbon-like organics from traffic, as well as sulfur-containing aerosol, to be the key pollution sources. Remarkable differences existed between complementary instruments, warranting the deployment of multiple tools at sites, with wide-ranging influences.
Zhongyi Zhang, Chunxiang Ye, Yichao Wu, Tao Zhou, Pengfei Chen, Shichang Kang, Chong Zhang, Zhuang Jiang, and Lei Geng
Atmos. Chem. Phys., 25, 10625–10641, https://doi.org/10.5194/acp-25-10625-2025, https://doi.org/10.5194/acp-25-10625-2025, 2025
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This study reveals unexpectedly high levels of particulate nitrite at the Base Camp of Mt. Qomolangma, which overwhelmingly exists in coarse mode, and demonstrates that lofted surface soil and long-range transported pollutants contribute to the high levels of nitrite. The high particulate nitrite is likely to participate in atmospheric reactive nitrogen cycling through gas-particle partitioning or photolysis, leading to production of HONO, OH and NO and thereby influencing oxidation chemistry.
Jakob Boyd Pernov, William H. Aeberhard, Michele Volpi, Eliza Harris, Benjamin Hohermuth, Sakiko Ishino, Ragnhild B. Skeie, Stephan Henne, Ulas Im, Patricia K. Quinn, Lucia M. Upchurch, and Julia Schmale
Atmos. Chem. Phys., 25, 6497–6537, https://doi.org/10.5194/acp-25-6497-2025, https://doi.org/10.5194/acp-25-6497-2025, 2025
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Particulate methanesulfonic acid (MSAp) is vital for the Arctic climate system. Numerical models struggle to reproduce the MSAp seasonal cycle. We evaluate three numerical models and one reanalysis product’s ability to simulate MSAp. We develop data-driven models for MSAp at four Arctic stations. The data-driven models outperform the numerical models and reanalysis product and identified precursor source-, chemical-processing-, and removal-related features as being important for modeling MSAp.
Kai Man, Xichen Li, Jürg Luterbacher, Lei Geng, Naiming Yuan, Yurong Hou, Yonghao Wang, and Yujie Miao
EGUsphere, https://doi.org/10.5194/egusphere-2025-1381, https://doi.org/10.5194/egusphere-2025-1381, 2025
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The West Antarctic Ice Sheet shows opposing snow accumulation trends: decreasing in the west and increasing in the east. Our study reveals that tropical ocean temperature shifts – Pacific cooling and Atlantic warming – drive changes in winds and moisture, boosting snowfall in the east while reducing it in the west. Using ice cores and models, we highlight how distant ocean changes shape Antarctic Ice Sheet, crucial for predicting future sea level rise.
Naoko Nagatsuka, Kumiko Goto-Azuma, Kana Nagashima, Koji Fujita, Yuki Komuro, Motohiro Hirabayashi, Jun Ogata, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Ayaka Yonekura, Fumio Nakazawa, Yukihiko Onuma, Naoyuki Kurita, Sune Olander Rasmussen, Giulia Sinnl, Trevor James Popp, and Dorthe Dahl-Jensen
EGUsphere, https://doi.org/10.5194/egusphere-2025-1522, https://doi.org/10.5194/egusphere-2025-1522, 2025
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We present the first continuous records of dust size, composition, and temporal variations in potential sources from the northeastern Greenland ice core (EGRIP) over the past 100 years. Using a multi-proxy provenance approach based on individual particle analysis, we identify the primary dust sources as the Asian (Gobi) and African (Sahara) deserts. Our findings show shifts in their contributions since the 1970s–1980s, highlighting the effectiveness of this approach during low dust periods.
Brice Barret, Patrice Medina, Natalie Brett, Roman Pohorsky, Kathy S. Law, Slimane Bekki, Gilberto J. Fochesatto, Julia Schmale, Steve R. Arnold, Andrea Baccarini, Maurizio Busetto, Meeta Cesler-Maloney, Barbara D'Anna, Stefano Decesari, Jingqiu Mao, Gianluca Pappaccogli, Joel Savarino, Federico Scoto, and William R. Simpson
Atmos. Meas. Tech., 18, 1163–1184, https://doi.org/10.5194/amt-18-1163-2025, https://doi.org/10.5194/amt-18-1163-2025, 2025
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The Fairbanks area experiences severe pollution episodes in winter because of enhanced emissions of pollutants trapped near the surface by strong temperature inversions. Low-cost sensors were deployed on board a car and a tethered balloon to measure the concentrations of gaseous pollutants (CO, O3, and NOx) in Fairbanks during winter 2022. Data calibration with reference measurements and machine learning methods enabled us to document pollution at the surface and power plant plumes aloft.
Xia Wang, Tao Che, Xueyin Ruan, Shanna Yue, Jing Wang, Chun Zhao, and Lei Geng
Geosci. Model Dev., 18, 651–670, https://doi.org/10.5194/gmd-18-651-2025, https://doi.org/10.5194/gmd-18-651-2025, 2025
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We employed the WRF-Chem model to parameterize atmospheric nitrate deposition in snow and evaluate its performance in simulating snow cover, snow depth, and concentrations of dust and nitrate using new observations from northern China. The results generally exhibit reasonable agreement with field observations in northern China, demonstrating the model's capability to simulate snow properties, including concentrations of reservoir species.
Natalie Brett, Kathy S. Law, Steve R. Arnold, Javier G. Fochesatto, Jean-Christophe Raut, Tatsuo Onishi, Robert Gilliam, Kathleen Fahey, Deanna Huff, George Pouliot, Brice Barret, Elsa Dieudonné, Roman Pohorsky, Julia Schmale, Andrea Baccarini, Slimane Bekki, Gianluca Pappaccogli, Federico Scoto, Stefano Decesari, Antonio Donateo, Meeta Cesler-Maloney, William Simpson, Patrice Medina, Barbara D'Anna, Brice Temime-Roussel, Joel Savarino, Sarah Albertin, Jingqiu Mao, Becky Alexander, Allison Moon, Peter F. DeCarlo, Vanessa Selimovic, Robert Yokelson, and Ellis S. Robinson
Atmos. Chem. Phys., 25, 1063–1104, https://doi.org/10.5194/acp-25-1063-2025, https://doi.org/10.5194/acp-25-1063-2025, 2025
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Processes influencing dispersion of local anthropogenic pollution in Arctic wintertime are investigated with Lagrangian dispersion modelling. Simulated power plant plume rise that considers temperature inversion layers improves results compared to observations (interior Alaska). Modelled surface concentrations are improved by representation of vertical mixing and emission estimates. Large increases in diesel vehicle emissions at temperatures reaching −35°C are required to reproduce observed NOx.
Kumiko Goto-Azuma, Yoshimi Ogawa-Tsukagawa, Kaori Fukuda, Koji Fujita, Motohiro Hirabayashi, Remi Dallmayr, Jun Ogata, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Sumito Matoba, Moe Kadota, Akane Tsushima, Naoko Nagatsuka, and Teruo Aoki
Atmos. Chem. Phys., 25, 657–683, https://doi.org/10.5194/acp-25-657-2025, https://doi.org/10.5194/acp-25-657-2025, 2025
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Monthly ice core records spanning 350 years from Greenland show trends in refractory black carbon (rBC) concentrations and sizes. rBC levels have increased since the 1870s due to the inflow of anthropogenic rBC, with larger diameters than those from biomass burning (BB) rBC. High summer BB rBC peaks may reduce the ice sheet albedo, but BB rBC showed no increase until the early 2000s. These results are vital for validating aerosol and climate models.
Kumiko Goto-Azuma, Remi Dallmayr, Yoshimi Ogawa-Tsukagawa, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Motohiro Hirabayashi, Jun Ogata, Kyotaro Kitamura, Kenji Kawamura, Koji Fujita, Sumito Matoba, Naoko Nagatsuka, Akane Tsushima, Kaori Fukuda, and Teruo Aoki
Atmos. Chem. Phys., 24, 12985–13000, https://doi.org/10.5194/acp-24-12985-2024, https://doi.org/10.5194/acp-24-12985-2024, 2024
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We developed a continuous flow analysis system to analyze an ice core from northwestern Greenland and coupled it with an improved refractory black carbon (rBC) measurement technique. This allowed accurate high-resolution analyses of size distributions and concentrations of rBC particles with diameters of 70 nm–4 μm for the past 350 years. Our results provide crucial insights into rBC's climatic effects. We also found previous ice core studies substantially underestimated rBC mass concentrations.
Tianming Ma, Zhuang Jiang, Minghu Ding, Pengzhen He, Yuansheng Li, Wenqian Zhang, and Lei Geng
The Cryosphere, 18, 4547–4565, https://doi.org/10.5194/tc-18-4547-2024, https://doi.org/10.5194/tc-18-4547-2024, 2024
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We constructed a box model to evaluate the isotope effects of atmosphere–snow water vapor exchange at Dome A, Antarctica. The results show clear and invisible diurnal changes in surface snow isotopes under summer and winter conditions, respectively. The model also predicts that the annual net effects of atmosphere–snow water vapor exchange would be overall enrichments in snow isotopes since the effects in summer appear to be greater than those in winter at the study site.
V. Holly L. Winton, Robert Mulvaney, Joel Savarino, Kyle R. Clem, and Markus M. Frey
Clim. Past, 20, 1213–1232, https://doi.org/10.5194/cp-20-1213-2024, https://doi.org/10.5194/cp-20-1213-2024, 2024
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In 2018, a new 120 m ice core was drilled in a region located under the Antarctic ozone hole. We present the first results including a 1300-year record of snow accumulation and aerosol chemistry. We investigate the aerosol and moisture source regions and atmospheric processes related to the ice core record and discuss what this means for developing a record of past ultraviolet radiation and ozone depletion using the stable isotopic composition of nitrate measured in the same ice core.
Zhuang Jiang, Becky Alexander, Joel Savarino, and Lei Geng
Atmos. Chem. Phys., 24, 4895–4914, https://doi.org/10.5194/acp-24-4895-2024, https://doi.org/10.5194/acp-24-4895-2024, 2024
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Ice-core nitrate could track the past atmospheric NOx and oxidant level, but its interpretation is hampered by the post-depositional processing. In this work, an inverse model was developed and tested against two polar sites and was shown to well reproduce the observed nitrate signals in snow and atmosphere, suggesting that the model can properly correct for the effect of post-depositional processing. This model offers a very useful tool for future studies on ice-core nitrate records.
Linia Tashmim, William C. Porter, Qianjie Chen, Becky Alexander, Charles H. Fite, Christopher D. Holmes, Jeffrey R. Pierce, Betty Croft, and Sakiko Ishino
Atmos. Chem. Phys., 24, 3379–3403, https://doi.org/10.5194/acp-24-3379-2024, https://doi.org/10.5194/acp-24-3379-2024, 2024
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Dimethyl sulfide (DMS) is mostly emitted from ocean surfaces and represents the largest natural source of sulfur for the atmosphere. Once in the atmosphere, DMS forms stable oxidation products such as SO2 and H2SO4, which can subsequently contribute to airborne particle formation and growth. In this study, we update the DMS oxidation mechanism in the chemical transport model GEOS-Chem and describe resulting changes in particle growth as well as the overall global sulfur budget.
Sarah Albertin, Joël Savarino, Slimane Bekki, Albane Barbero, Roberto Grilli, Quentin Fournier, Irène Ventrillard, Nicolas Caillon, and Kathy Law
Atmos. Chem. Phys., 24, 1361–1388, https://doi.org/10.5194/acp-24-1361-2024, https://doi.org/10.5194/acp-24-1361-2024, 2024
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This study reports the first simultaneous records of oxygen (Δ17O) and nitrogen (δ15N) isotopes in nitrogen dioxide (NO2) and nitrate (NO3−). These data are combined with atmospheric observations to explore sub-daily N reactive chemistry and quantify N fractionation effects in an Alpine winter city. The results highlight the necessity of using Δ17O and δ15N in both NO2 and NO3− to avoid biased estimations of NOx sources and fates from NO3− isotopic records in urban winter environments.
Vigan Mensah, Koji Fujita, Stephen Howell, Miho Ikeda, Mizuki Komatsu, and Kay I. Ohshima
EGUsphere, https://doi.org/10.5194/egusphere-2023-2492, https://doi.org/10.5194/egusphere-2023-2492, 2023
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We estimated the volume of freshwater released by sea ice, glaciers, rivers, and precipitation into Baffin Bay and the Labrador Sea, and their changes over the past 70 years. We found that the freshwater volume has risen in Baffin Bay due to increased glacier melting, and dropped in the Labrador Sea because of the decline in sea ice production. We also infer that freshwater from the Arctic Ocean has been exported to our study region for the past 30 years, possibly as a result of global warming.
Motoshi Nishimura, Teruo Aoki, Masashi Niwano, Sumito Matoba, Tomonori Tanikawa, Tetsuhide Yamasaki, Satoru Yamaguchi, and Koji Fujita
Earth Syst. Sci. Data, 15, 5207–5226, https://doi.org/10.5194/essd-15-5207-2023, https://doi.org/10.5194/essd-15-5207-2023, 2023
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We presented the method of data quality checks and the dataset for two ground weather observations in northwest Greenland. We found that the warm and clear weather conditions in the 2015, 2019, and 2020 summers caused the snowmelt and the decline in surface reflectance of solar radiation at a low-elevated site (SIGMA-B; 944 m), but those were not seen at the high-elevated site (SIGMA-A; 1490 m). We hope that our data management method and findings will help climate scientists.
Alexis Lamothe, Joel Savarino, Patrick Ginot, Lison Soussaintjean, Elsa Gautier, Pete D. Akers, Nicolas Caillon, and Joseph Erbland
Atmos. Meas. Tech., 16, 4015–4030, https://doi.org/10.5194/amt-16-4015-2023, https://doi.org/10.5194/amt-16-4015-2023, 2023
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Ammonia is a reactive gas in our atmosphere that is key in air quality issues. Assessing its emissions and how it reacts is a hot topic that can be addressed from the past. Stable isotopes (the mass of the molecule) measured in ice cores (glacial archives) can teach us a lot. However, the concentrations in ice cores are very small. We propose a protocol to limit the contamination and apply it to one ice core drilled in Mont Blanc, describing the opportunities our method brings.
Yukihiko Onuma, Koji Fujita, Nozomu Takeuchi, Masashi Niwano, and Teruo Aoki
The Cryosphere, 17, 3309–3328, https://doi.org/10.5194/tc-17-3309-2023, https://doi.org/10.5194/tc-17-3309-2023, 2023
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We established a novel model that simulates the temporal changes in cryoconite hole (CH) depth using heat budgets calculated independently at the ice surface and CH bottom based on hole shape geometry. The simulations suggest that CH depth is governed by the balance between the intensity of the diffuse component of downward shortwave radiation and the wind speed. The meteorological conditions may be important factors contributing to the recent ice surface darkening via the redistribution of CHs.
Naoko Nagatsuka, Kumiko Goto-Azuma, Koji Fujita, Yuki Komuro, Motohiro Hirabayashi, Jun Ogata, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Ayaka Yonekura, Fumio Nakazawa, Yukihiko Onuma, Naoyuki Kurita, Sune Olander Rasmussen, Giulia Sinnl, Trevor James Popp, and Dorthe Dahl-Jensen
EGUsphere, https://doi.org/10.5194/egusphere-2023-1666, https://doi.org/10.5194/egusphere-2023-1666, 2023
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We present a new high-temporal-resolution record of mineral composition in a northeastern Greenland ice-core (EGRIP) over the past 100 years. The ice core dust composition and its variation differed significantly from a northwestern Greenland ice core, which is likely due to differences in the geological sources of the dust. Our results suggest that the EGRIP ice core dust was constantly supplied from Northern Eurasia, North America, and Asia with minor contribution from Greenland coast.
Simone Ventisette, Samuele Baldini, Claudio Artoni, Silvia Becagli, Laura Caiazzo, Barbara Delmonte, Massimo Frezzotti, Raffaello Nardin, Joel Savarino, Mirko Severi, Andrea Spolaor, Barbara Stenni, and Rita Traversi
EGUsphere, https://doi.org/10.5194/egusphere-2023-393, https://doi.org/10.5194/egusphere-2023-393, 2023
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The paper reports the spatial variability of concentration and fluxes of chemical impurities in superficial snow over unexplored area of the East Antarctic ice sheet. Pinatubo and Puyehue-Cordón Caulle volcanic eruptions in non-sea salt sulfate and dust snow pits record were used to achieve the accumulation rates. Deposition (wet, dry and uptake from snow surface) and post deposition processes are constrained. These knowledges are fundamental in Antarctic ice cores stratigraphies interpretation.
Pete D. Akers, Joël Savarino, Nicolas Caillon, Olivier Magand, and Emmanuel Le Meur
Atmos. Chem. Phys., 22, 15637–15657, https://doi.org/10.5194/acp-22-15637-2022, https://doi.org/10.5194/acp-22-15637-2022, 2022
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Nitrate isotopes in Antarctic ice do not preserve the seasonal isotopic cycles of the atmosphere, which limits their use to study the past. We studied nitrate along an 850 km Antarctic transect to learn how these cycles are changed by sunlight-driven chemistry in the snow. Our findings suggest that the snow accumulation rate and other environmental signals can be extracted from nitrate with the right sampling and analytical approaches.
Jiajia Wang, Hongxi Pang, Shuangye Wu, Spruce W. Schoenemann, Ryu Uemura, Alexey Ekaykin, Martin Werner, Alexandre Cauquoin, Sentia Goursaud Oger, Summer Rupper, and Shugui Hou
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-384, https://doi.org/10.5194/essd-2022-384, 2022
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Stable water isotopic observations in surface snow over Antarctica provide a basis for validating isotopic models and interpreting Antarctic ice core records. This study presents a new compilation of Antarctic surface snow isotopic dataset based on published and unpublished sources. The database has a wide range of potential applications in studying spatial distribution of water isotopes, model validation, and reconstruction and interpretation of Antarctic ice core records.
Yanzhi Cao, Zhuang Jiang, Becky Alexander, Jihong Cole-Dai, Joel Savarino, Joseph Erbland, and Lei Geng
Atmos. Chem. Phys., 22, 13407–13422, https://doi.org/10.5194/acp-22-13407-2022, https://doi.org/10.5194/acp-22-13407-2022, 2022
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We investigate the potential of ice-core preserved nitrate isotopes as proxies of stratospheric ozone variability by measuring nitrate isotopes in a shallow ice core from the South Pole. The large variability in the snow accumulation rate and its slight increase after the 1970s masked any signals caused by the ozone hole. Moreover, the nitrate oxygen isotope decrease may reflect changes in the atmospheric oxidation environment in the Southern Ocean.
Albane Barbero, Roberto Grilli, Markus M. Frey, Camille Blouzon, Detlev Helmig, Nicolas Caillon, and Joël Savarino
Atmos. Chem. Phys., 22, 12025–12054, https://doi.org/10.5194/acp-22-12025-2022, https://doi.org/10.5194/acp-22-12025-2022, 2022
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The high reactivity of the summer Antarctic boundary layer results in part from the emissions of nitrogen oxides produced during photo-denitrification of the snowpack, but its underlying mechanisms are not yet fully understood. The results of this study suggest that more NO2 is produced from the snowpack early in the photolytic season, possibly due to stronger UV irradiance caused by a smaller solar zenith angle near the solstice.
Xueyin Ruan, Chun Zhao, Rahul A. Zaveri, Pengzhen He, Xinming Wang, Jingyuan Shao, and Lei Geng
Geosci. Model Dev., 15, 6143–6164, https://doi.org/10.5194/gmd-15-6143-2022, https://doi.org/10.5194/gmd-15-6143-2022, 2022
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Accurate prediction of aerosol pH in chemical transport models is essential to aerosol modeling. This study examines the performance of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) on aerosol pH predictions and the sensitivities to emissions of nonvolatile cations and NH3, aerosol-phase state assumption, and heterogeneous sulfate production. Temporal evolution of aerosol pH during haze cycles in Beijing and the driving factors are also presented and discussed.
Tomotaka Saruya, Shuji Fujita, Yoshinori Iizuka, Atsushi Miyamoto, Hiroshi Ohno, Akira Hori, Wataru Shigeyama, Motohiro Hirabayashi, and Kumiko Goto-Azuma
The Cryosphere, 16, 2985–3003, https://doi.org/10.5194/tc-16-2985-2022, https://doi.org/10.5194/tc-16-2985-2022, 2022
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Crystal orientation fabrics (COF) of the Dome Fuji ice core were investigated with an innovative method with unprecedentedly high statistical significance and dense depth coverage. The COF profile and its fluctuation were found to be highly dependent on concentrations of chloride ion and dust. The data suggest deformation of ice at the deepest zone is highly influenced by COF fluctuations that progressively develop from the near-surface firn toward the deepest zone within ice sheets.
Zhuang Jiang, Joel Savarino, Becky Alexander, Joseph Erbland, Jean-Luc Jaffrezo, and Lei Geng
The Cryosphere, 16, 2709–2724, https://doi.org/10.5194/tc-16-2709-2022, https://doi.org/10.5194/tc-16-2709-2022, 2022
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A record of year-round atmospheric nitrate isotopic composition along with snow nitrate isotopic data from Summit, Greenland, revealed apparent enrichments in nitrogen isotopes in snow nitrate compared to atmospheric nitrate, in addition to a relatively smaller degree of changes in oxygen isotopes. The results suggest that at this site post-depositional processing takes effect, which should be taken into account when interpreting ice-core nitrate isotope records.
Yota Sato, Koji Fujita, Hiroshi Inoue, Akiko Sakai, and Karma
The Cryosphere, 16, 2643–2654, https://doi.org/10.5194/tc-16-2643-2022, https://doi.org/10.5194/tc-16-2643-2022, 2022
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We investigate fluctuations in Bhutanese lake-terminating glaciers focusing on the dynamics change before and after proglacial lake formation at Thorthormi Glacier (TG) based on photogrammetry, satellite, and GPS surveys. The thinning rate of TG became double compared to before proglacial lake formation, and the flow velocity has also sped up considerably. Those changes would be due to the reduction in longitudinal ice compression by the detachment of the glacier terminus from the end moraine.
Saehee Lim, Meehye Lee, Joel Savarino, and Paolo Laj
Atmos. Chem. Phys., 22, 5099–5115, https://doi.org/10.5194/acp-22-5099-2022, https://doi.org/10.5194/acp-22-5099-2022, 2022
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We determined δ15N(NO3−) and Δ17O(NO3−) of PM2.5 in Seoul during 2018–2019 and estimated quantitatively the contribution of oxidation pathways to NO3− formation and NOx emission sources. The nighttime pathway played a significant role in NO3− formation during the winter, and its contribution further increased up to 70 % on haze days when PM2.5 was greater than 75 µg m−3. Vehicle emissions were confirmed as a main NO3− source with an increasing contribution from coal combustion in winter.
Cited articles
Akers, P. D., Savarino, J., Caillon, N., Servettaz, A. P. M., Le Meur, E., Magand, O., Martins, J., Agosta, C., Crockford, P., Kobayashi, K., Hattori, S., Curran, M., van Ommen, T., Jong, L., and Roberts, J. L.: Sunlight-driven nitrate loss records Antarctic surface mass balance, Nat. Commun., 13, 4274, https://doi.org/10.1038/s41467-022-31855-7, 2022.
Alexander, B., Savarino, J., Kreutz, K. J., and Thiemens, M. H.: Impact of preindustrial biomass-burning emissions on the oxidation pathways of tropospheric sulfur and nitrogen, J. Geophys. Res.-Atmos., 109, D08303, https://doi.org/10.1029/2003JD004218, 2004.
Alexander, B., Hastings, M. G., Allman, D. J., Dachs, J., Thornton, J. A., and Kunasek, S. A.: Quantifying atmospheric nitrate formation pathways based on a global model of the oxygen isotopic composition (Δ17O) of atmospheric nitrate, Atmos. Chem. Phys., 9, 5043–5056, https://doi.org/10.5194/acp-9-5043-2009, 2009.
Alexander, B., Sherwen, T., Holmes, C. D., Fisher, J. A., Chen, Q., Evans, M. J., and Kasibhatla, P.: Global inorganic nitrate production mechanisms: comparison of a global model with nitrate isotope observations, Atmos. Chem. Phys., 20, 3859–3877, https://doi.org/10.5194/acp-20-3859-2020, 2020.
Amino, T., Iizuka, Y., Matoba, S., Shimada, R., Oshima, N., Suzuki, T., Ando, T., Aoki, T., and Fujita, K.: Increasing dust emission from ice free terrain in southeastern Greenland since 2000, Polar Sci., 27, 100599, https://doi.org/10.1016/j.polar.2020.100599, 2021.
Bekker, C., Walters, W. W., Murray, L. T., and Hastings, M. G.: Nitrate chemistry in the northeast US – Part 1: Nitrogen isotope seasonality tracks nitrate formation chemistry, Atmos. Chem. Phys., 23, 4185–4201, https://doi.org/10.5194/acp-23-4185-2023, 2023.
Berhanu, T. A., Meusinger, C., Erbland, J., Jost, R., Bhattacharya, S. K., Johnson, M. S., and Savarino, J.: Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence, J. Chem. Phys., 140, 244306, https://doi.org/10.1063/1.4882899, 2014.
Berhanu, T. A., Savarino, J., Erbland, J., Vicars, W. C., Preunkert, S., Martins, J. F., and Johnson, M. S.: Isotopic effects of nitrate photochemistry in snow: a field study at Dome C, Antarctica, Atmos. Chem. Phys., 15, 11243–11256, https://doi.org/10.5194/acp-15-11243-2015, 2015.
Beyn, F., Matthias, V., and Dähnke, K.: Changes in atmospheric nitrate deposition in Germany – An isotopic perspective, Environ. Pollut., 194, 1–10, https://doi.org/10.1016/j.envpol.2014.06.043, 2014.
Chai, J., Miller, D. J., Scheuer, E., Dibb, J., Selimovic, V., Yokelson, R., Zarzana, K. J., Brown, S. S., Koss, A. R., Warneke, C., and Hastings, M.: Isotopic characterization of nitrogen oxides (NOx), nitrous acid (HONO), and nitrate (pNO
Domine, F., Taillandier, A. S., and Simpson, W. R.: A parameterization of the specific surface area of seasonal snow for field use and for models of snowpack evolution, J. Geophys. Res.-Earth Surf., 112, F02031, https://doi.org/10.1029/2006JF000512, 2007.
Duce, R. A., LaRoche, J., Altieri, K., Arrigo, K. R., Baker, A. R., Capone, D. G., Cornell, S., Dentener, F., Galloway, J., Ganeshram, R. S., Geider, R. J., Jickells, T., Kuypers, M. M., Langlois, R., Liss, P. S., Liu, S. M., Middelburg, J. J., Moore, C. M., Nickovic, S., Oschlies, A., Pedersen, T., Prospero, J., Schlitzer, R., Seitzinger, S., Sorensen, L. L., Uematsu, M., Ulloa, O., Voss, M., Ward, B., and Zamora, L.: Impacts of atmospheric anthropogenic nitrogen on the open ocean, Science, 320, 893–897, https://doi.org/10.1126/science.1150369, 2008.
Eichler, A., Legrand, M., Jenk, T. M., Preunkert, S., Andersson, C., Eckhardt, S., Engardt, M., Plach, A., and Schwikowski, M.: Consistent histories of anthropogenic western European air pollution preserved in different Alpine ice cores, The Cryosphere, 17, 2119–2137, https://doi.org/10.5194/tc-17-2119-2023, 2023.
Elliott, E. M., Yu, Z., Cole, A. S., and Coughlin, J. G.: Isotopic advances in understanding reactive nitrogen deposition and atmospheric processing, Sci. Total Environ., 662, 393–403, https://doi.org/10.1016/j.scitotenv.2018.12.177, 2019.
Erbland, J., Vicars, W. C., Savarino, J., Morin, S., Frey, M. M., Frosini, D., Vince, E., and Martins, J. M. F.: Air–snow transfer of nitrate on the East Antarctic Plateau – Part 1: Isotopic evidence for a photolytically driven dynamic equilibrium in summer, Atmos. Chem. Phys., 13, 6403–6419, https://doi.org/10.5194/acp-13-6403-2013, 2013.
Erbland, J., Savarino, J., Morin, S., France, J. L., Frey, M. M., and King, M. D.: Air–snow transfer of nitrate on the East Antarctic Plateau – Part 2: An isotopic model for the interpretation of deep ice-core records, Atmos. Chem. Phys., 15, 12079–12113, https://doi.org/10.5194/acp-15-12079-2015, 2015.
Felix, J. D. and Elliott, E. M.: The agricultural history of human-nitrogen interactions as recorded in ice core δ15N-NO3−, Geophys. Res. Lett., 40, 1642–1646, https://doi.org/10.1002/grl.50209, 2013.
Freyer, H. D.: Seasonal variation of 15N/14N ratios in atmospheric nitrate species, Tellus B, 43, 30–44, https://doi.org/10.1034/j.1600-0889.1991.00003.x, 1991.
Freyer, H. D., Kobel, K., Delmas, R. J., Kley, D., and Legrand, M. R.: First results of 15N/14N ratios in nitrate from alpine and polar ice cores, Tellus B, 48, 93–105, https://doi.org/10.1034/j.1600-0889.1996.00009.x, 1996.
Fibiger, D. L., Dibb, J. E., Chen, D., Thomas, J. L., Burkhart, J. F., Huey, L. G., and Hastings, M. G.: Analysis of nitrate in the snow and atmosphere at Summit, Greenland: Chemistry and transport, J. Geophys. Res.-Atmos., 121, 5010–5030, https://doi.org/10.1002/2015JD024187, 2016.
Finlayson-Pitts, B. J. and Pitts, J. N.: Chemistry of the upper and lower atmosphere: Theory, experiments, and applications, Academic Press, San Diego, https://doi.org/10.1016/B978-0-12-257060-5.X5000-X, 2000.
Frey, M. M., Savarino, J., Morin, S., Erbland, J., and Martins, J. M. F.: Photolysis imprint in the nitrate stable isotope signal in snow and atmosphere of East Antarctica and implications for reactive nitrogen cycling, Atmos. Chem. Phys., 9, 8681–8696, https://doi.org/10.5194/acp-9-8681-2009, 2009.
Furukawa, R., Uemura, R., Fujita, K., Sjolte, J., Yoshimura, K., Matoba, S., and Iizuka, Y.: Seasonal-scale dating of a shallow ice core from Greenland using oxygen isotope matching between data and simulation, J. Geophys. Res.-Atmos., 122, 873–887, https://doi.org/10.1002/2017jd026716, 2017.
Geng, L., Alexander, B., Cole-Dai, J., Steig, E. J., Savarino, J., Sofen, E. D., and Schauer, A. J.: Nitrogen isotopes in ice core nitrate linked to anthropogenic atmospheric acidity change, P. Natl. Acad. Sci. USA, 111, 5808–5812, https://doi.org/10.1073/pnas.1319441111, 2014.
Geng, L., Zatko, M. C., Alexander, B., Fudge, T. J., Schauer, A. J., Murray, L. T., and Mickley, L. J.: Effects of post-depositional processing on nitrogen isotopes of nitrate in the Greenland Ice Sheet Project 2 ice core, Geophys. Res. Lett., 42, 5346–5354, https://doi.org/10.1002/2015gl064218, 2015.
Geng, L., Murray, L. T., Mickley, L. J., Lin, P., Fu, Q., Schauer, A. J., and Alexander, B.: Isotopic evidence of multiple controls on atmospheric oxidants over climate transitions, Nature, 546, 133–136, https://doi.org/10.1038/nature22340, 2017.
Hastings, M. G.: Evaluating source, chemistry and climate change based upon the isotopic composition of nitrate in ice cores, IOP Conf. Ser.: Earth Environ. Sci., 9, 012002, https://doi.org/10.1088/1755-1315/9/1/012002, 2010.
Hastings, M. G., Sigman, D. M., and Steig, E. J.: Glacial/interglacial changes in the isotopes of nitrate from the Greenland Ice Sheet Project 2 (GISP2) ice core, Global Biogeochem. Cycles, 19, GB4024, https://doi.org/10.1029/2005GB002502, 2005.
Hastings, M. G., Jarvis, J. C., and Steig, E. J.: Anthropogenic impacts on nitrogen isotopes of ice-core nitrate, Science, 324, 1288, https://doi.org/10.1126/science.1170510, 2009.
Hastings, M. G., Casciotti, K. L., and Elliott, E. M.: Stable isotopes as tracers of anthropogenic nitrogen sources, deposition, and impacts, Elements, 9, 339–344, https://doi.org/10.2113/gselements.9.5.339, 2013.
Hattori, S., Savarino, J., Kamezaki, K., Ishino, S., Dyckmans, J., Fujinawa, T., Caillon, N., Barbero, A., Mukotaka, A., Toyoda, S., Well, R., and Yoshida, N.: Automated system measuring triple oxygen and nitrogen isotope ratios in nitrate using the bacterial method and N2O decomposition by microwave discharge, Rapid Commun. Mass Spectrom., 30, 2635–2644, https://doi.org/10.1002/rcm.7747, 2016.
Hattori, S., Iizuka, Y., Alexander, B., Ishino, S., Fujita, K., Zhai, S., Sherwen, T., Oshima, N., Uemura, R., Yamada, A., Suzuki, N., Matoba, S., Tsuruta, A., Savarino, J., and Yoshida, N.: Isotopic evidence for acidity-driven enhancement of sulfate formation after SO2 emission control, Sci. Adv., 7, eabd4610, https://doi.org/10.1126/sciadv.abd4610, 2021.
Hattori, S., Li, Z. Q., Yoshida, N., and Takeuchi, N.: Isotopic evidence for microbial nitrogen cycling in a glacier interior of high-mountain Asia, Environ. Sci. Technol., 57, 15026–15036, https://doi.org/10.1021/acs.est.3c04757, 2023.
Heaton, T. H. E.: Ratios of nitrate and ammonium in rain at Pretoria, South Africa, Atmos. Environ., 21, 843–852, https://doi.org/10.1016/0004-6981(87)90080-1, 1987.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Holm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020.
Honrath, R., Lu, Y., Peterson, M. C., Dibb, J. E., Arsenault, M., Cullen, N., and Steffen, K. J. A. E.: Vertical fluxes of NOx, HONO, and HNO3 above the snowpack at Summit, Greenland, Atmos. Environ., 36, 2629–2640, 2002.
Iizuka, Y., Matoba, S., Yamasaki, T., Oyabu, I., Kadota, M., and Aoki, T.: Glaciological and meteorological observations at the SE-Dome site, southeastern Greenland Ice Sheet, B. Glaciol. Res., 34, 1–10, https://doi.org/10.5331/bgr.15R03, 2016.
Iizuka, Y., Miyamoto, A., Hori, A., Matoba, S., Furukawa, R., Saito, T., Fujita, S., Hirabayashi, M., Yamaguchi, S., Fujita, K., and Takeuchi, N.: A firn densification process in the high accumulation dome of Southeastern Greenland, Arct. Antarct. Alp. Res., 49, 13–27, https://doi.org/10.1657/AAAR0016-034, 2017.
Iizuka, Y., Uemura, R., Fujita, K., Hattori, S., Seki, O., Miyamoto, C., Suzuki, T., Yoshida, N., Motoyama, H., and Matoba, S.: A 60 year record of atmospheric aerosol depositions preserved in a high-accumulation dome ice core, Southeast Greenland, J. Geophys. Res.-Atmos., 123, 574–589, https://doi.org/10.1002/2017JD026733, 2018.
Iizuka, Y., Matoba, S., Minowa, M., Yamasaki, T., Kawakami, K., Kakugo, A., Miyahara, M., Hashimoto, A., Niwano, M., Tanikawa, T., Fujita, K., and Aoki, T.: Ice core drilling and the related observations at SE-Dome site, Southeastern Greenland Ice Sheet, Bull. Glaciol. Res., 39, 1–12, https://doi.org/10.5331/bgr.21R01, 2021.
Jarvis, J. C., Hastings, M. G., Steig, E. J., and Kunasek, S. A.: Isotopic ratios in gas-phase HNO3 and snow nitrate at Summit, Greenland, J. Geophys. Res.-Atmos., 114, D17301, https://doi.org/10.1029/2009JD012134, 2009.
Jiang, Z., Alexander, B., Savarino, J., Erbland, J., and Geng, L.: Impacts of the photo-driven post-depositional processing on snow nitrate and its isotopes at Summit, Greenland: a model-based study, The Cryosphere, 15, 4207–4220, https://doi.org/10.5194/tc-15-4207-2021, 2021.
Jiang, Z., Alexander, B., Savarino, J., and Geng, L.: An inverse model to correct for the effects of post-depositional processing on ice-core nitrate and its isotopes: model framework and applications at Summit, Greenland, and Dome C, Antarctica, Atmos. Chem. Phys., 24, 4895–4914, https://doi.org/10.5194/acp-24-4895-2024, 2024.
Kahl, J. D. W., Martinez, D. A., Kuhns, H., Davidson, C. I., Jaffrezo, J.-L., and Harris, J. M.: Air mass trajectories to Summit, Greenland: A 44-year climatology and some episodic events, J. Geophys. Res.-Oceans, 102, 26861–26875, https://doi.org/10.1029/97JC00296, 1997.
Kawakami, K., Iizuka, Y., Sasage, M., Matsumoto, M., Saito, T., Hori, A., Ishino, S., Fujita, S., Fujita, K., Takasugi, K., Hatakeyama, T., Hamamoto, S., Watari, A., Esashi, N., Otsuka, M., Uemura, R., Horiuchi, K., Minowa, M., Hattori, S., Aoki, T., Hirabayashi, M., Kawamura, K., and Matoba, S.: SE-Dome II ice core dating with half-year precision: increasing melting events from 1799 to 2020 in Southeastern Greenland, J. Geophys. Res.-Atmos., 128, e2023JD038874, https://doi.org/10.1029/2023JD038874, 2023.
Kendall, M. G. J. L. L: Rank correlation methods. 4th edn., Charles Griffin, London, https://archive.org/details/rankcorrelationm0000kend (last access: 6 June 2025), 1975.
Khalzan, P., Sakai, A., and Fujita, K.: Mass balance of four mongolian glaciers: in-situ measurements, long-term reconstruction and sensitivity analysis, Front. Earth Sci., 9, 785306, https://doi.org/10.3389/feart.2021.785306, 2022.
Law, K., Hjorth, J., Pernov, J., Whaley, C., Skov, H., Coen, M., and Zhang, K.: Arctic tropospheric ozone trends, Geophys. Res. Lett., 50, e2023GL103096, https://doi.org/10.1029/2023GL103096, 2023.
Li, Z., Hastings, M. G., Walters, W. W., Tian, L., Clemens, S. C., Song, L., and Fang, Y.: Isotopic evidence that recent agriculture overprints climate variability in nitrogen deposition to the Tibetan Plateau, Environ. Int., 138, 105614, https://doi.org/10.1016/j.envint.2020.105614, 2020.
Lim, S., Lee, M., Savarino, J., and Laj, P.: Oxidation pathways and emission sources of atmospheric particulate nitrate in Seoul: based on δ15N and Δ17O measurements, Atmos. Chem. Phys., 22, 5099–5115, https://doi.org/10.5194/acp-22-5099-2022, 2022.
Mann, H. B.: Non-parametric tests against trend, Econometrica, 13, 245–259, https://doi.org/10.2307/1907187, 1945.
Mayewski, P. A., Lyons, W. B., Spencer, M. J., Twickler, M., Dansgaard, W., Koci, B., and Honrath, R. E.: Sulfate and nitrate concentrations from a south Greenland ice core, Science, 232, 975–977, https://doi.org/10.1126/science.232.4753.975, 1986.
McCabe, J. R., Boxe, C. S., Colussi, A. J., Hoffmann, M. R., and Thiemens, M. H.: Oxygen isotopic fractionation in the photochemistry of nitrate in water and ice, J. Geophys. Res.-Atmos., 110, 148–227, https://doi.org/10.1029/2004JD005484, 2005.
McIlvin, M. R., and Casciotti, K. L.: Technical updates to the bacterial method for nitrate isotopic analyses, Anal. Chem., 83, 1850–1856, https://doi.org/10.1021/ac1028984, 2011.
Meusinger, C., Berhanu, T. A., Erbland, J., Savarino, J., and Johnson, M. S.: Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry, J. Chem. Phys., 140, 244305, https://doi.org/10.1063/1.4882898, 2014.
Michalski, G., Scott, Z., Kabiling, M., and Thiemens, M. H.: First measurements and modeling of Δ17O in atmospheric nitrate, Geophys. Res. Lett., 30, 1870, https://doi.org/10.1029/2003GL017015, 2003.
Michalski, G., Bhattacharya, S. K., and Mase, D. F.: Oxygen Isotope Dynamics of Atmospheric Nitrate and Its Precursor Molecules, in: Handbook of Environmental Isotope Geochemistry, edited by: Baskaran, M., Advances in Isotope Geochemistry, Springer, Berlin, Heidelberg, https://doi.org/10.1007/978-3-642-10637-8_30, 2012.
Morin, S., Savarino, J., Frey, M. M., Yan, N., Bekki, S., Bottenheim, J. W., and Martins, J. M.: Tracing the origin and fate of NOx in the Arctic atmosphere using stable isotopes in nitrate, Science, 322, 730–732, https://doi.org/10.1126/science.1161910, 2008.
Morin, S., Savarino, J., Frey, M. M., Domine, F., Jacobi, H. W., Kaleschke, L., and Martins, J. M. F.: Comprehensive isotopic composition of atmospheric nitrate in the Atlantic Ocean boundary layer from 65° S to 79° N, J. Geophys. Res.-Atmos., 114, D05303, https://doi.org/10.1029/2008JD010696, 2009.
Morin, S., Erbland, J., Savarino, J., Domine, F., Bock, J., Friess, U., Jacobi, H.-W., Sihler, H., and Martins, J. M. F.: An isotopic view on the connection between photolytic emissions of NOx from the Arctic snowpack and its oxidation by reactive halogens, J. Geophys. Res.-Atmos., 117, D00R08, https://doi.org/10.1029/2011JD016618, 2012.
Neftel, A., Moor, E., Oeschger, H., and Stauffer, B.: Evidence from polar ice cores for the increase in atmospheric CO2 in the past two centuries, Nature, 315, 45–47, https://doi.org/10.1038/315045a0, 1985.
Noro, K., Hattori, S., Uemura, R., Fukui, K., Hirabayashi, M., Kawamura, K., Motoyama, H., Takenaka, N., and Yoshida, N.: Spatial variation of isotopic compositions of snowpack nitrate related to post-depositional processes in eastern Dronning Maud Land, East Antarctica, Geochem. J., 52, e7–e14, https://doi.org/10.2343/geochemj.2.0519, 2018.
Oyabu, I., Matoba, S., Yamasaki, T., Kadota, M., and Iizuka, Y.: Seasonal variations in the major chemical species of snow at the Southeast Dome in Greenland, Polar Sci., 10, 36–42, https://doi.org/10.1016/j.polar.2016.01.003, 2016.
Parvin, F., Seki, O., Fujita, K., Iizuka, Y., Matoba, S., Ando, T., and Sawada, K.: Assessment for paleoclimatic utility of biomass burning tracers in SE-Dome ice core, Greenland, Atmos. Environ., 196, 86–94, https://doi.org/10.1016/j.atmosenv.2018.10.012, 2019.
Röthlisberger, R., Hutterli, M. A., Sommer, S., Wolff, E. W., and Mulvaney, R.: Factors controlling nitrate in ice cores: Evidence from the Dome C deep ice core, J. Geophys. Res.-Atmos., 105, 20565–20572, https://doi.org/10.1029/2000JD900264, 2000.
Röthlisberger, R., Hutterli, M. A., Wolff, E. W., Mulvaney, R., Fischer, H., Bigler, M., Goto-Azuma, K., Hansson, M. E., Ruth, U., Siggaard-Andersen, M.-L., and Steffensen, J. P.: Nitrate in Greenland and Antarctic ice cores: a detailed description of post-depositional processes, Ann. Glaciol., 35, 209–216, https://doi.org/10.3189/172756402781817220, 2002.
Savarino, J., Kaiser, J., Morin, S., Sigman, D. M., and Thiemens, M. H.: Nitrogen and oxygen isotopic constraints on the origin of atmospheric nitrate in coastal Antarctica, Atmos. Chem. Phys., 7, 1925–1945, https://doi.org/10.5194/acp-7-1925-2007, 2007.
Sigman, D. M., Casciotti, K. L., Andreani, M., Barford, C., Galanter, M., and Böhlke, J. K.: A Bacterial Method for the Nitrogen Isotopic Analysis of Nitrate in Seawater and Freshwater, Anal. Chem., 73, 4145–4153, https://doi.org/10.1021/ac010088e, 2001.
Shammas, N. K., Wang, L. K., and Wang, M. H. S.: Sources, chemistry and control of acid rain in the environment, in: Handbook of Environment and Waste Management, 1–26, https://doi.org/10.1142/9789811207136_0001, 2020.
Shi, G., Ma, H., Zhu, Z., Hu, Z., Chen, Z., Jiang, S., An, C., Yu, J., Ma, T., Li, Y., Sun, B., and Hastings, M. G.: Using stable isotopes to distinguish atmospheric nitrate production and its contribution to the surface ocean across hemispheres, Earth Planet. Sci. Lett., 564, 116914, https://doi.org/10.1016/j.epsl.2021.116914, 2021.
Shi, G., Buffen, A. M., Hu, Y., Chai, J., Li, Y., Wang, D., and Hastings, M. G.: Modeling the complete nitrogen and oxygen isotopic imprint of nitrate photolysis in snow, Geophys. Res. Lett., 50, e2023GL103778, https://doi.org/10.1029/2023GL103778, 2023.
Song, W., Liu, X. Y., Hu, C. C., Chen, G. Y., Liu, X. J., Walters, W. W., Michalski, G., and Liu, C. Q.: Important contributions of non-fossil fuel nitrogen oxides emissions, Nat. Commun., 12, 243, https://doi.org/10.1038/s41467-020-20356-0, 2021.
Stein, A. F., Draxler, R. R., Rolph, G. D., Stunder, B. J. B., Cohen, M. D., and Ngan, F.: NOAA's HYSPLIT atmospheric transport and dispersion modeling system, B. Am. Meteorol. Soc., 96, 2059–2077, https://doi.org/10.1175/BAMS-D-14-00110.1, 2015.
The International GEOS-Chem User Community: geoschem/geos-chem: GEOS-Chem 12.9.3 (12.9.3), Zenodo [code], https://doi.org/10.5281/zenodo.3974569, 2020.
Vega, C. P., Pohjola, V. A., Samyn, D., Pettersson, R., Isaksson, E., Björkman, M. P., Martma, T., Marca, A., and Kaiser, J.: First ice core records of NO
Vicars, W. and Savarino, J.: Quantitative constraints on the 17O-excess (Δ17O) signature of surface ozone: Ambient measurements from 50° N to 50° S using the nitrite-coated filter technique, Geochim. Cosmochim. Ac., 135, 270–287, https://doi.org/10.1016/j.gca.2014.03.023, 2014.
Walters, W. W. and Michalski, G.: Theoretical calculation of nitrogen isotope equilibrium exchange fractionation factors for various NOy molecules, Geochim. Cosmochim. Ac., 164, 284–297, https://doi.org/10.1016/j.gca.2015.05.029, 2015a.
Walters, W. W., Goodwin, S. R., and Michalski, G.: Nitrogen stable isotope composition (δ15N) of vehicle-emitted NOx, Environ. Sci. Technol., 49, 2278–2285, https://doi.org/10.1021/es505580v, 2015b.
Walters, W. W. and Michalski, G.: Theoretical calculation of oxygen equilibrium isotope fractionation factors involving various NOy molecules, OH, and H2O and its implications for isotope variations in atmospheric nitrate, Geochim. Cosmochim. Ac., 191, 89–101, https://doi.org/10.1016/j.gca.2016.06.039, 2016.
Wei, Z., Hattori, S., Tsuruta, A., Jiang, Z., Ishino, S., Fujita, K., Matoba, S., Geng, L., Lamothe, A., Uemura, R., Yoshida, N., Savarino, J., and Iizuka, Y.: A 60-year atmospheric nitrate isotope record from a Southeast Greenland ice core with minimal post-depositional alteration, Hokkaido University [data set], https://doi.org/10.14943/hu94240, 2025.
Zatko, M., Geng, L., Alexander, B., Sofen, E., and Klein, K.: The impact of snow nitrate photolysis on boundary layer chemistry and the recycling and redistribution of reactive nitrogen across Antarctica and Greenland in a global chemical transport model, Atmos. Chem. Phys., 16, 2819–2842, https://doi.org/10.5194/acp-16-2819-2016, 2016.
Zhai, S., Jacob, D. J., Wang, X., Liu, Z., Wen, T., Shah, V., Li, K., Moch, J. M., Bates, K. H., Song, S., Shen, L., Zhang, Y., Luo, G., Yu, F., Sun, Y., Wang, L., Qi, M., Tao, J., Gui, K., Xu, H., Zhang, Q., Zhao, T., Wang, Y., Lee, H. C., Choi, H., and Liao, H.: Control of particulate nitrate air pollution in China, Nat. Geosci., 14, 389–395, https://doi.org/10.1038/s41561-021-00726-z, 2021.
Short summary
Nitrate isotope records in ice cores reveal changes in NOₓ emissions and atmospheric oxidation chemistry driven by human activity. However, UV-driven postdepositional processes can alter nitrate in snow, making snow accumulation rates critical for preserving these records. This study examines nitrate isotopes in a southeastern Greenland ice core, where high snow accumulation minimizes these effects, providing a reliable archive of atmospheric nitrogen cycling.
Nitrate isotope records in ice cores reveal changes in NOₓ emissions and atmospheric oxidation...
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