Reply on RC1/RC2 DOI Creative Commons

Kaley Walker

Published: Feb. 22, 2024

Abstract. The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) is currently providing the only measurements of vertically resolved chlorodifluoromethane (HCFC-22) from space. This study assesses ACE-FTS HCFC-22 v5.2 product in upper troposphere – lower stratosphere, as well simulated concentrations a 39-year specified dynamics run Canadian Middle Atmosphere Model (CMAM39) same region. In general, observations tend to agree with subsampled CMAM39 data within ±5 %, except for between ~15 and 25 km extratropical regions where exhibits negative bias 5–30 near 6 tropics ACE FTS 15 %. When comparing against correlative satellite, aircraft, balloon data, typically low on order 0–10 % ~5–15 ±15 ~15–25 km. ACE-FTS, CMAM39, surface flask NOAA Global Monitoring Laboratory’s air-sampling network, all exhibit consistent tropospheric trends ranging 6.8 7.8 pptv/year (within 95 confidence) 2004–2012, 3.1 4.7 2012–2018. Interhemispheric differences (IHD) were also derived using NOAA, three yielded correlated (r≥0.42) IHD timeseries, results indicating that values decreased at rate 2.2±1.1 pptv/decade 2004 2018.

Language: Английский

Age of Stratospheric Air: Progress on Processes, Observations, and Long‐Term Trends DOI Creative Commons
Hella Garny, Felix Ploeger, Marta Ábalos

et al.

Reviews of Geophysics, Journal Year: 2024, Volume and Issue: 62(4)

Published: Oct. 21, 2024

Abstract Age of stratospheric air is a well established metric for the transport circulation. Rooted in robust theoretical framework, this approach offers benefit being deducible from observations trace gases. Given potential climate‐induced changes, observational constraints on circulation are crucial. In past two decades, scientific progress has been made three main areas: (a) Enhanced process understanding and development diagnostics led to better quantification individual processes model deficits. (b) The global age climatology now constrained by thanks improved quality quantity data, including satellite through consistent calculation methods. (c) It understood that models predict decrease age, is, an accelerating circulation, response forcing greenhouse gases ozone depleting substances. Observational records confirm long‐term forced trends mean lower stratosphere. However, mid‐stratosphere, uncertainties too large or disprove predictions. Continuous monitoring further methods derive those tracers will be crucial constrain variability observations. Future work as important due its enhance composition address climate biases, assess impacts proposed geoengineering

Language: Английский

Citations

9
Validation of the version 4.5 MAESTRO ozone and NO2 measurements DOI Creative Commons
Paul S. Jeffery, J. R. Drummond,

C. T. McElroy

et al.

Atmospheric measurement techniques, Journal Year: 2025, Volume and Issue: 18(3), P. 569 - 602

Published: Feb. 3, 2025

Abstract. Launched aboard the Canadian SCISAT satellite in August 2003, Measurement of Aerosol Extinction Stratosphere and Troposphere Retrieved by Occultation (MAESTRO) instrument has been measuring solar absorption spectra ultraviolet (UV) visible part spectrum for more than 20 years. The UV-channel measurements from MAESTRO are used to retrieve profiles ozone short-wavelength end Chappuis band (UV-ozone) NO2, while made a separate (Vis-ozone) product. latest NO2 profile products, version 4.5, have released, they initially cover period February 2004 December 2023, although will continue be updated. 4.5 retrieval algorithm represents an improvement previous versions, with changes including updated pressure temperature input information, improved high-Sun reference calculation, Rayleigh scattering modelling, change Twomey–Tikhonov inversion Chahine relaxation technique. Due buildup unknown contaminant, UV-ozone products only viable up June 2009 UV-ozone. This study presents comparisons coincident (both spatially temporally) ensemble 11 other limb-viewing instruments. In stratosphere, Vis-ozone product was found possess small high bias, stratosphere-averaged relative differences between 2.3 % 8.2 %, good agreement comparison datasets overall. A similar albeit slightly poorer agreement, is average stratospheric ranging 2.8 11.9 %. For general range 40 km. Within this range, low bias most agree within 27.2 ranges 8.5 43.4

Language: Английский

Citations

0
Highlighting the Impact of Anthropogenic OCS Emissions on the Stratospheric Sulfur Budget With In Situ Observations DOI Creative Commons
Colin Gurganus, Andrew W. Rollins, Eleanor M. Waxman

et al.

Journal of Geophysical Research Atmospheres, Journal Year: 2025, Volume and Issue: 130(9)

Published: May 6, 2025

Abstract Carbonyl sulfide (OCS) is an important atmospheric sulfur species that plays a dominant role in the formation of (nonvolcanic) stratospheric sulfate aerosol middle stratosphere. Major uncertainties surface sources and sinks inconsistent model representation vertical transport limit understanding OCS distribution, particularly sparsely sampled upper atmosphere. During 2022 Asian Summer Monsoon Chemical CLimate Impact Project (ACCLIP) campaign, situ measurements Upper Troposphere Lower Stratosphere (UTLS) at eastern edge summer monsoon anticyclone (ASM), showed significant enhancements (>750 ppt) near tropopause from convectively influenced air parcels. Here, we compare these novel UTLS with long‐term satellite observations regional to broaden trends its by ASM. Trajectory analysis identifies northern China as main source region for deep convective lofting OCS‐enriched parcels demonstrates ASM entrainment UTLS, allowing evaluation global predictions OCS's influence. The ACCLIP data set provides vital validation limited vertically resolved anthropogenic emissions, which serves enhance our budget.

Language: Английский

Citations

0
Record‐High Ozone in the Austral Mid‐Latitude Tropopause Region Driven by Dynamical and Chemical Effects of the 2019 Sudden Stratospheric Warming DOI Creative Commons
Selena Zhang,

Susan Solomon,

Jun Zhang

et al.

Geophysical Research Letters, Journal Year: 2025, Volume and Issue: 52(9)

Published: May 10, 2025

Abstract In January 2020, tropopause‐level ozone in the austral mid‐latitudes was highest ever observed available Microwave Limb Sounder data record since 2004. Two extreme events preceded this anomaly: Australian Black Summer fires and 2019 sudden stratospheric warming (SSW), raising question of how these disruptions influenced Southern Hemisphere ozone. Here, we investigate dynamical chemical contributions to anomaly using a chemistry‐climate model satellite observations. We find that downward transport polar ozone‐enriched air due SSW later spread equatorward. Such together with photochemical production from emissions wildfires (fueled by dry hot conditions previously attributed SSW) increased up 30 ppb, as dominant factor (around 80%). While is well‐recognized, our results highlight SSWs can greatly influence mid‐latitude through effects.

Language: Английский

Citations

0
Validation of Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) chlorodifluoromethane (HCFC-22) in the upper troposphere and lower stratosphere DOI Creative Commons
Felicia Kolonjari,

Patrick E. Sheese,

K. A. Walker

et al.

Atmospheric measurement techniques, Journal Year: 2024, Volume and Issue: 17(8), P. 2429 - 2449

Published: April 23, 2024

Abstract. The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) is currently providing the only measurements of vertically resolved chlorodifluoromethane (HCFC-22) from space. This study assesses ACE-FTS HCFC-22 v5.2 product in upper troposphere and lower stratosphere, as well simulations a 39-year specified dynamics run Canadian Middle Atmosphere Model (CMAM39) same region. In general, observations tend to agree with subsampled CMAM39 data within ±5 %, except for between ∼ 15 25 km extratropical regions where exhibits negative bias 5 %–30 % near 6 tropics −15 %. When comparing against correlative satellite, aircraft, balloon data, typically low on order 0 %–10 ±15 km. ACE-FTS, CMAM39, surface flask NOAA Global Monitoring Laboratory's air-sampling network all exhibit consistent tropospheric trends ranging 6.8 7.8 ppt yr−1 (within 95 confidence) 2004–2012 3.1 4.7 2012–2018. Interhemispheric differences (IHDs) were also derived using NOAA, three yielded correlated (r≥0.42) IHD time series, results indicating that values decreased at rate 2.2 ± 1.1 per decade 2004 2018.

Language: Английский

Citations

3
Sulfate aerosol properties derived from combining coincident ACE-FTS and SAGE III/ISS measurements DOI
C. D. Boone, P. F. Bernath,

A. Pastorek

et al.

Journal of Quantitative Spectroscopy and Radiative Transfer, Journal Year: 2023, Volume and Issue: 312, P. 108815 - 108815

Published: Oct. 23, 2023

Language: Английский

Citations

7
First HFC-134a retrievals from ground-based FTIR solar absorption spectra, comparison with TOMCAT model simulations, in-situ AGAGE observations, and ACE-FTS satellite data for the Jungfraujoch station DOI
Irene Pardo Cantos, Emmanuel Mahieu, Martyn P. Chipperfield

et al.

Journal of Quantitative Spectroscopy and Radiative Transfer, Journal Year: 2024, Volume and Issue: 318, P. 108938 - 108938

Published: Feb. 10, 2024

Language: Английский

Citations

2
Atmospheric effects of the Tonga volcanic sulfate aerosols DOI
Neil Raymond, P. F. Bernath, C. D. Boone

et al.

Journal of Quantitative Spectroscopy and Radiative Transfer, Journal Year: 2024, Volume and Issue: 324, P. 109056 - 109056

Published: May 23, 2024

Language: Английский

Citations

2
Trends in atmospheric composition between 2004–2023 using version 5 ACE-FTS data DOI Creative Commons
Matthew Schmidt, P. F. Bernath, C. D. Boone

et al.

Journal of Quantitative Spectroscopy and Radiative Transfer, Journal Year: 2024, Volume and Issue: 325, P. 109088 - 109088

Published: June 18, 2024

The Atmospheric Chemistry Experiment (ACE) is a satellite mission that has been in orbit since 2003. primary instrument on ACE Fourier transform spectrometer (FTS) records infrared atmospheric transmittance spectra the limb geometry using Sun as light source. Version 5 of ACE-FTS data processing contains improved volume mixing ratio (VMR) profiles for 46 molecules and 24 isotopologues, including HFC-32 (CH2F2) HOCl new routine products. VMR trends each are reported regions interest. Specifically, longevity provided an opportunity to monitor effectiveness Montreal Protocol Substances Deplete Ozone Layer. It observed chlorofluorocarbons (CFCs) declining, hydrochlorofluorocarbons (HCFCs) no longer increasing, but hydrofluorocarbons (HFCs) still increasing rapidly. Greenhouse gases such carbon dioxide also monitored comparisons with National Oceanic Administration (NOAA) Advanced Global Gases (AGAGE) measurements made.

Language: Английский

Citations

2
Antarctic Polar Stratospheric Cloud Analysis of ACE‐FTS Data From 2005 to 2023 DOI Creative Commons
Michael J. Lecours, C. D. Boone, P. F. Bernath

et al.

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(13)

Published: June 28, 2024

Abstract We present an analysis of Antarctic polar winters from 2005 to 2023 as observed by the Atmospheric Chemistry Experiment (ACE). The unique broad band infrared spectral features in ACE “residual” spectra are used classify aerosols composition into stratospheric clouds (PSCs) and sulfate aerosols. PSCs further classified nitric acid trihydrate, supercooled ternary solutions, acid, ice‐mix, mixtures PSCs. A breakdown PSC is presented for each year. winter seasons with unusual compositions are: 2011, which volcanic ash mixed was July August; 2019, experienced a warming event; 2020, season following Australian Black Summer pyrocumulonimbus 2023, had unusually large Honga‐Tonga Honga Ha'apai eruption 2022.

Language: Английский

Citations

2