Article
Multidisciplinary Sciences
Paul J. Young, Anna B. Harper, Chris Huntingford, Nigel D. Paul, Olaf Morgenstern, Paul A. Newman, Luke D. Oman, Sasha Madronich, Rolando R. Garcia
Summary: Modelling suggests that the Montreal Protocol is helping to mitigate climate change by protecting the land carbon sink and the ozone layer, as well as by reducing greenhouse gas emissions. This is achieved through control of ozone-depleting substances, which has led to the recovery of the ozone layer and avoided harmful increases in ultraviolet radiation. Additionally, the Protocol has co-benefits for plants and their capacity to store carbon, which has not been investigated previously.
Article
Geosciences, Multidisciplinary
Wuhu Feng, Sandip S. Dhomse, Carlo Arosio, Mark Weber, John P. Burrows, Michelle L. Santee, Martyn P. Chipperfield
Summary: Using a three-dimensional chemical transport model and satellite observations, researchers investigated the Arctic ozone depletion in winter/spring 2019/20 and compared it with previous years. Persistently low temperatures led to extensive chlorine activation, while weak dynamical replenishment played a key role in causing very low column ozone values in the region. The study also showed that the gradual recovery of the ozone layer over the past two decades alleviated the polar cap ozone depletion in March 2020 by around 20 DU.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Stephen O. Andersen, Song Gao, Suely Carvalho, Tad Ferris, Marco Gonzalez, Nancy J. Sherman, Yiyao Wei, Durwood Zaelke
Summary: The Montreal Protocol can be strengthened to control ozone-depleting substances and hydrofluorocarbons, while also mitigating plastics pollution through narrowing the scope of feedstock exemptions. This upstream approach can effectively reduce inadvertent and unauthorized emissions and guide the choice of environmentally superior substitutes.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Mark R. England, Lorenzo M. Polvani
Summary: The melting of Arctic sea ice, largely due to anthropogenic climate change, is projected to result in the first ice-free Arctic summer by mid-century. Ozone-depleting substances (ODSs), which have been regulated since the late 1980s by the Montreal Protocol, have also contributed to this ice loss. Using climate model simulations, it is demonstrated that the Montreal Protocol is delaying the occurrence of an ice-free Arctic summer by up to 15 years, solely due to the reduction in greenhouse gas warming from regulated ODSs. Furthermore, it is estimated that each Gg of reduced ODS emissions leads to 7 km2 of avoided Arctic sea ice loss.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Meteorology & Atmospheric Sciences
Zhe Wang, Jiankai Zhang, Tao Wang, Wuhu Feng, Yihang Hu, Xiran Xu
Summary: The factors influencing the size of the Antarctic ozone hole in November are mainly dynamic processes, with weaker ozone transport related to planetary wave divergence in the stratosphere. Anomalously large ozone holes in November are not always preceded by large holes in late winter, and processes for large and small holes are generally opposite.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
N. A. Davis, D. Visioni, R. R. Garcia, D. E. Kinnison, D. R. Marsh, M. Mills, J. H. Richter, S. Tilmes, C. G. Bardeen, A. Gettelman, A. A. Glanville, D. G. Macmartin, A. K. Smith, F. Vitt
Summary: Simulating the dynamics, chemistry, and physics of the entire atmosphere is computationally expensive. Simplified chemistry configurations can reliably simulate the whole atmosphere with reduced computational resources, except for cases requiring an accurate representation of tropospheric organic chemistry and secondary organic aerosols.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2023)
Article
Meteorology & Atmospheric Sciences
I Wohltmann, P. von der Gathen, R. Lehmann, H. Deckelmann, G. L. Manney, J. Davies, D. Tarasick, N. Jepsen, R. Kivi, N. Lyall, M. Rex
Summary: The winter of 2019/2020 in the Arctic stratosphere had the lowest observed ozone mixing ratios and was characterized by an unusually strong and long-lasting polar vortex. Some aspects of this winter resemble both Antarctic and Arctic conditions, such as the chemical processes and chlorine activation reactions. If the air masses had spent slightly more time below the upper temperature limit for polar stratospheric cloud formation and in sunlight, ozone levels in parts of the vortex could have been reduced to near zero values.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Geosciences, Multidisciplinary
L. A. Rieger, W. J. Randel, A. E. Bourassa, S. Solomon
Summary: After the 2020 Australian bushfires, satellite observations documented stratospheric aerosol, temperature, and ozone anomalies in the Southern Hemisphere. The anomalies were comparable to the effects of the Calbuco eruption in 2015, with enhanced aerosols and warm temperature anomalies leading to midlatitude ozone depletion. The overall effects resembled those of the 2015 eruption, with record low ozone levels and polar temperatures.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
F. Robertson, L. E. Revell, H. Douglas, A. T. Archibald, O. Morgenstern, D. Frame
Summary: Research suggests that the year when total column ozone (TCO) returns to 1980 levels is commonly used as an indicator of recovery from ozone-depleting substances. However, this date is somewhat arbitrary. In this study, the signal-to-noise (S/N) metric from climate change research is used to investigate how TCO might return to pre-ozone hole era levels. The findings show that a return to 1980 levels does not necessarily represent TCO recovery to pre-disturbance conditions, and the S/N ratio is a more appropriate and complementary metric.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
F. Robertson, L. E. Revell, H. Douglas, A. T. Archibald, O. Morgenstern, D. Frame
Summary: The year when total column ozone (TCO) returns to 1980 levels is commonly used to measure recovery from ozone-depleting substances. However, this metric fails to account for internal variability and the timing of significant TCO losses. Using the signal-to-noise (S/N) metric, this study investigates how TCO can return to pre-disturbance conditions. The findings suggest that TCO de-emerges before returning to its 1980 value, making S/N a suitable metric for determining TCO recovery.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Jingwen Liu, Sihui Wang, Qiangqiang Yuan, Feng Zhang, Liye Zhu
Summary: This study derives the vertical ozone profile from the troposphere to the stratosphere by combining ozone retrievals from MLS and TES. The combined products have been validated and found to have smaller biases compared to MLS or TES alone.
Article
Geosciences, Multidisciplinary
Pengfei Yu, Robert W. Portmann, Yifeng Peng, Cheng-Cheng Liu, Yunqian Zhu, Elizabeth Asher, Zhixuan Bai, Ye Lu, Jianchun Bian, Michael Mills, Anja Schmidt, Karen H. Rosenlof, Owen B. Toon
Summary: Volcanic and wildfire events between 2014 and 2022 injected 3.2 Tg of sulfur dioxide and 0.8 Tg of smoke aerosols into the stratosphere. The simulated stratospheric lifetime of the injections during this period is 50% longer than previous volcanic injections. These injections resulted in a global mean effective radiative forcing of -0.18 W m(-2), which is 40% of the radiative forcing caused by the Pinatubo eruption. The smoke aerosols from wildfires have a greater negative radiative forcing compared to volcanic sulfate.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Letter
Biodiversity Conservation
Paul W. Barnes, Janet F. Bornman, Krishna K. Pandey, Germar H. Bernhard, Alkiviadis F. Bais, Rachel E. Neale, Thomas Matthew Robson, Patrick J. Neale, Craig E. Williamson, Richard G. Zepp, Sasha Madronich, Stephen R. Wilson, Anthony L. Andrady, Anu M. Heikkila, Sharon A. Robinson
Summary: The Montreal Protocol and its Amendments have been highly effective in protecting the stratospheric ozone layer, reducing global warming, and preventing global increases in UV-B radiation. However, ongoing and projected changes in UV-B radiation and climate still pose threats to human health, ecosystems, and construction materials.
GLOBAL CHANGE BIOLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Karina E. Adcock, Paul J. Fraser, Brad D. Hall, Ray L. Langenfelds, Geoffrey Lee, Stephen A. Montzka, David E. Oram, Thomas Rockmann, Fred Stroh, William T. Sturges, Baerbel Vogel, Johannes C. Laube
Summary: Recent studies have shown that the Asian summer monsoon anticyclone transports emissions from rapidly industrializing nations into the upper troposphere, affecting ozone-depleting substances (ODSs) concentrations. Measurements from air samples collected during the summers of 2016 and 2017 revealed higher than expected levels of ODSs, including chlorinated very short-lived substances. Trajectory analysis indicated South Asia as a possible source region for some ODSs. These findings suggest a potential impact on the stratospheric ozone layer.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Biodiversity Conservation
Robert W. Murdoch, Gao Chen, Fadime Kara Murdoch, E. Erin Mack, Manuel I. Villalobos Solis, Robert L. Hettich, Frank E. Loffler
Summary: The discovery of a gene cluster responsible for anaerobic degradation of dichloromethane (DCM) in specialized bacteria suggests that DCM may serve as an energy source in various environmental systems, with potential implications for global DCM flux.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Environmental Sciences
Ao Chen, Di Chen, Xiaoyi Hu, Christina M. Harth, Dickon Young, Jens Muehle, Paul B. Krummel, Simon O'Doherty, Ray F. Weiss, Ronald G. Prinn, Xuekun Fang
Summary: This study used ACE-FTS satellite observations to assess global concentrations and emissions of ozone-depleting substances, hydrofluorocarbons, and methyl chloride. The results showed that satellite observations were consistent with ground-based observations, implying that satellite observations could be used to monitor the progress of the Montreal Protocol.
ENVIRONMENTAL POLLUTION
(2023)
Article
Geochemistry & Geophysics
M. M. J. Crismani, R. M. Tyo, N. M. Schneider, J. M. C. Plane, W. Feng, J. D. Carrillo-Sanchez, G. L. Villanueva, S. Jain, J. Deighan, S. Curry
Summary: Since the discovery of atmospheric Mg+ on Mars in 2015, continuous observations of this meteoric ion layer have been conducted. This study presents the most comprehensive observations of the persistent metal ion layer, showing that Mg+ appears under various conditions with peak densities varying between 100 and 500 cm(-3). Significant latitudinal variation within a season suggests that Mg+ is influenced by meteoric input distribution and/or atmospheric dynamics and chemistry. Counter-intuitive results, such as a reduction of Mg+ ions during Northern Winter in the northern hemisphere, are also observed.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Geosciences, Multidisciplinary
Wuhu Feng, John M. C. Plane, Martyn P. P. Chipperfield, Alfonso Saiz-Lopez, Jean-Paul Booth
Summary: We used a 3-D Whole Atmospheric Community Climate Model to examine the effects of small satellite launches with an iodine propulsion system on stratospheric ozone depletion. The model suggests that the emissions from these satellites can reach the troposphere within a 4-year timescale. In the base case scenario of 40,000 small satellite launches per year, the impact on global stratospheric ozone is negligible, while a 100-fold increase in launch rate could lead to significant ozone depletion over the polar regions.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Luke M. Western, Martin K. Vollmer, Paul B. Krummel, Karina E. Adcock, Paul J. Fraser, Christina M. Harth, Ray L. Langenfelds, Stephen A. Montzka, Jens Muehle, Simon O'Doherty, David E. Oram, Stefan Reimann, Matt Rigby, Isaac Vimont, Ray F. Weiss, Dickon Young, Johannes C. Laube
Summary: Despite the ban on production, the levels of five chlorofluorocarbons in the atmosphere increased between 2010 and 2020, probably due to by-products of hydrofluorocarbon production. This contradicts the goals of the Montreal Protocol to phase out these substances.
Correction
Geosciences, Multidisciplinary
Luke M. Western, Martin K. Vollmer, Paul B. Krummel, Karina E. Adcock, Molly Crotwell, Paul J. Fraser, Christina M. Harth, Ray L. Langenfelds, Stephen A. Montzka, Jens Muehle, Simon O'Doherty, David E. Oram, Stefan Reimann, Matt Rigby, Isaac Vimont, Ray F. Weiss, Dickon Young, Johannes C. Laube
Article
Environmental Sciences
Julian Villamayor, Fernando Iglesias-Suarez, Carlos A. Cuevas, Rafael P. Fernandez, Qinyi Li, Marta Abalos, Ryan Hossaini, Martyn P. Chipperfield, Douglas E. Kinnison, Simone Tilmes, Jean-Francois Lamarque, Alfonso Saiz-Lopez
Summary: In contrast to the overall recovery of stratospheric ozone, recent observations show ongoing net ozone depletion in the tropical lower stratosphere. This depletion is thought to be driven by dynamical transport accelerated by global warming, while chemical processes have been considered unimportant. However, using a chemistry-climate model, researchers demonstrate that halogenated ozone-depleting very short-lived substances (VSLS) chemistry may account for a significant portion of this observed ozone loss. They predict that the contribution of VSLS to ozone depletion will persist throughout the twenty-first century in the tropical lower stratosphere, emphasizing the need for mitigation strategies to preserve the ozone layer in low latitudes.
NATURE CLIMATE CHANGE
(2023)
Article
Meteorology & Atmospheric Sciences
Marine Remaud, Jin Ma, Maarten Krol, Camille Abadie, Michael P. Cartwright, Prabir Patra, Yosuke Niwa, Christian Rodenbeck, Sauveur Belviso, Linda Kooijmans, Sinikka Lennartz, Fabienne Maignan, Frederic Chevallier, Martyn P. Chipperfield, Richard J. Pope, Jeremy J. Harrison, Isaac Vimont, Christopher Wilson, Philippe Peylin
Summary: This study evaluates the performance of atmospheric transport models in simulating carbonyl sulfide (COS) and finds that the models have significant deviations in simulating COS mixing ratios, especially in tropical and high latitude regions.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Engineering, Environmental
Minde An, Luke M. Western, Jianxin Hu, Bo Yao, Jens Muhle, Anita L. Ganesan, Ronald G. Prinn, Paul B. Krummel, Ryan Hossaini, Xuekun Fang, Simon O'Doherty, Ray F. Weiss, Dickon Young, Matthew Rigby
Summary: In this study, the emissions of chloroform (CHCl3) from China were estimated using atmospheric measurement-based top-down inverse modeling and a sector-based bottom-up inventory method. The emissions of CHCl3 increased from 78 Gg/yr in 2011 to a maximum of 193 Gg/yr in 2017, followed by a decrease to 147 Gg/yr in 2018. The changes in emissions from China accounted for all of the global changes in CHCl3 during the study period. The dominant sources of CHCl3 emissions in China were anthropogenic, such as byproduct emissions during disinfection and leakage from chloromethane industries.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Quanliang Chen, Yujing Liao, Xin Zhou, Ting Duan, Xiaotian Xue, Ziqi Zhang, Dandan Dong, Wuhu Feng
Summary: The impact of El Nino on the moisture in the tropical lower stratosphere has been extensively studied. The unprecedented hydration during the extreme El Nino in 2015/2016 provides an opportunity to distinguish the response of water vapor to extreme and moderate El Nino events.
Article
Meteorology & Atmospheric Sciences
Jin Ma, Marine Remaud, Philippe Peylin, Prabir Patra, Yosuke Niwa, Christian Rodenbeck, Mike Cartwright, Jeremy J. Harrison, Martyn P. Chipperfield, Richard J. Pope, Christopher Wilson, Sauveur Belviso, Stephen A. Montzka, Isaac Vimont, Fred Moore, Elliot L. Atlas, Efrat Schwartz, Maarten C. Krol
Summary: This study presents a comparison of atmospheric transport models for simulating carbonyl sulfide (COS) and evaluates the distribution and cycling of COS in the atmosphere. The results show good agreement between model simulations and observations, and highlight the importance of vertical mixing strength in explaining model differences. The findings provide important insights for further investigations of COS global distribution and budget analysis.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Optics
P. Bernath, D. Cameron
Summary: The TiO A3 & phi;-X3 & UDelta; electronic transition (& gamma; system) plays an important role in the opacity of M dwarf stars and hot Jupiter exoplanet atmospheres. The spectroscopic constants and line positions for the minor isotopologues 46TiO, 47TiO, 49TiO, and 50TiO in the 0-0 and 0-1 bands have been analyzed based on experimental data. A total of 8248 lines in the A3 & phi;-X3 & UDelta; transition, covering wavenumbers from 12,827 cm-1 to 14,172 cm-1 (780-706 nm) with J values from 1 to 70, have been fitted. The TiO emission spectrum used for analysis was recorded at the McMath-Pierce Solar Telescope in Kitt Peak, Arizona.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2023)
Article
Geosciences, Multidisciplinary
Cyril Caram, Sophie Szopa, Anne Cozic, Slimane Bekki, Carlos A. Cuevas, Alfonso Saiz-Lopez
Summary: The atmospheric chemistry of halogenated species plays a significant role in the global chemical sink of tropospheric ozone and affects the oxidising capacity of the troposphere, notably by influencing the atmospheric lifetime of methane. This study implemented tropospheric sources and chemistry of halogens in the LMDZ-INCA model and evaluated their effects on the tropospheric ozone budget. The results showed that the model satisfactorily simulated the impact of halogens on the photo-oxidising system, with a significant decrease in ozone burden, OH, and NOx when tropospheric halogens were considered.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Environmental Sciences
Ilaria Quaglia, Claudia Timmreck, Ulrike Niemeier, Daniele Visioni, Giovanni Pitari, Christina Brodowsky, Christoph Bruehl, Sandip S. Dhomse, Henning Franke, Anton Laakso, Graham W. Mann, Eugene Rozanov, Timofei Sukhodolov
Summary: This study compares the simulation results of six global models with observational data on the stratospheric aerosol cloud following the 1991 Mt. Pinatubo eruption. The results show consistent agreement in the rapid reduction of sulfate mass burden in the tropical stratosphere and transport towards the extratropics in the Northern Hemisphere. However, the models overestimate the initial sulfate burden and produce higher surface area density compared to observations.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Geography, Physical
Francois Burgay, Rafael Pedro Fernandez, Delia Segato, Clara Turetta, Christopher S. Blaszczak-Boxe, Rachael H. Rhodes, Claudio Scarchilli, Virginia Ciardini, Carlo Barbante, Alfonso Saiz-Lopez, Andrea Spolaor
Summary: Based on a 210-year bromine record, this study finds that the bromine signal in ice at Dome C in East Antarctica is preserved and not influenced by variations in ultraviolet radiation. However, due to limited satellite measurements and low sea-ice variability in the past 30 years, the effectiveness of bromine enrichment as a proxy for past sea-ice reconstructions at Dome C is still uncertain.
Article
Optics
P. Bernath, D. English, C. Boone, D. Cameron
Summary: Using ACE satellite data, the global patterns and seasonal trends of stratospheric NO2 and HNO3, including their 15N isotopes, have been investigated. The study reveals that different isotopes of NO2 and HNO3 exhibit variations in abundance at different latitudes and altitudes.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2023)
