Detection of elevated tropospheric hydrogen peroxide (H2O2) mixing ratios in atmospheric chemistry experiment (ACE) subtropical infrared solar occultation spectra

Abstract. The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is an infrared (IR) limb emission spectrometer on the Envisat platform. It measures trace gas distributions during day and night, pole-to-pole, over an altitude range from 6 to 70 km in nominal mode and up to 170 km in special modes, depending on the measurement mode, producing more than 1000 profiles day−1. We present the results of a validation study of methane, version V5R_CH4_222, retrieved with the IMK/IAA (Institut für Meteorologie und Klimaforschung, Karlsruhe/Instituto de Astrofisica de Andalucia, Grenada) MIPAS scientific level 2 processor. The level 1 spectra are provided by the ESA (European Space Agency) and version 5 was used. The time period covered is 2005–2012, which corresponds to the period when MIPAS measured trace gas distributions at a reduced spectral resolution of 0.0625 cm−1. The comparison with satellite instruments includes the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the HALogen Occultation Experiment (HALOE), the Solar Occultation For Ice Experiment (SOFIE) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). Furthermore, comparisons with MkIV balloon-borne solar occultation measurements and with air sampling measurements performed by the University of Frankfurt are presented. The validation activities include bias determination, assessment of stability, precision validation, analysis of histograms and comparison of corresponding climatologies. Above 50 km altitude, MIPAS methane mixing ratios agree within 3 % with ACE-FTS and SOFIE. Between 30 and 40 km an agreement within 3 % with SCIAMACHY has been found. In the middle stratosphere, there is no clear indication of a MIPAS bias since comparisons with various instruments contradict each other. In the lower stratosphere (below 25 km) MIPAS CH4 is biased high with respect to satellite instruments, and the most likely estimate of this bias is 14 %. However, in the comparison with CH4 data obtained from cryogenic whole-air sampler (cryosampler) measurements, there is no evidence of a high bias in MIPAS between 20 and 25 km altitude. Precision validation is performed on collocated MIPAS–MIPAS pairs and suggests a slight underestimation of its uncertainties by a factor of 1.2. No significant evidence of an instrumental drift has been found.

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Sunset–sunrise difference in solar occultation ozone measurements (SAGE II, HALOE, and ACE–FTS) and its relationship to tidal vertical winds

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-16043-2014 ◽

2014 ◽

Vol 14 (11) ◽

pp. 16043-16083

Author(s):

T. Sakazaki ◽

M. Shiotani ◽

M. Suzuki ◽

D. Kinnison ◽

J. M. Zawodny ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Seasonal Variations ◽

Climate Model ◽

Transport Model ◽

Stratospheric Aerosol ◽

Chemical Transport Model ◽

Latitude Range ◽

Solar Occultation ◽

Vertical Winds ◽

Chemistry Experiment

Abstract. This paper contains a comprehensive investigation of the sunset–sunrise difference (SSD; i.e., the sunset-minus-sunrise value) of the ozone mixing ratio in the latitude range of 10° S–10° N. SSD values were determined from solar occultation measurements based on data obtained from the Stratospheric Aerosol and Gas Experiment (SAGE) II, the Halogen Occultation Experiment (HALOE), and the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS). The SSD was negative at altitudes of 20–30 km (–0.1 ppmv at 25 km) and positive at 30–50 km (+0.2 ppmv at 40–45 km) for HALOE and ACE–FTS data. SAGE II data also showed a qualitatively similar result, although the SSD in the upper stratosphere was two times larger than those derived from the other datasets. On the basis of an analysis of data from the Superconducting Submillimeter Limb Emission Sounder (SMILES), and a nudged chemical-transport model (the Specified Dynamics version of the Whole Atmosphere Community Climate Model: SD–WACCM), we conclude that the SSD can be explained by diurnal variations in the ozone concentration, particularly those caused by vertical transport by the atmospheric tidal winds. All datasets showed significant seasonal variations in the SSD; the SSD in the upper stratosphere is greatest from December through February, while that in the lower stratosphere reaches a maximum twice: during the periods March–April and September–October. Based on an analysis of SD–WACCM results, we found that these seasonal variations follow those associated with the tidal vertical winds.

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Aerosol extinction profiles at 525 nm and 1020 nm derived from ACE imager data: comparisons with GOMOS, SAGE II, SAGE III, POAM III, and OSIRIS

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-2027-2008 ◽

2008 ◽

Vol 8 (7) ◽

pp. 2027-2037 ◽

Cited By ~ 16

Author(s):

F. Vanhellemont ◽

C. Tetard ◽

A. Bourassa ◽

M. Fromm ◽

J. Dodion ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Trace Gas ◽

Aerosol Extinction ◽

Optical Extinction ◽

Solar Occultation ◽

Comparison Results ◽

Stellar Occultation ◽

Relative Differences ◽

Atmospheric Trace Gas ◽

Chemistry Experiment

Abstract. The Canadian ACE (Atmospheric Chemistry Experiment) mission is dedicated to the retrieval of a large number of atmospheric trace gas species using the solar occultation technique in the infrared and UV/visible spectral domain. However, two additional solar disk imagers (at 525 nm and 1020 nm) were added for a number of reasons, including the retrieval of aerosol and cloud products. In this paper, we present first comparison results for these imager aerosol/cloud optical extinction coefficient profiles, with the ones derived from measurements performed by 3 solar occultation instruments (SAGE II, SAGE III, POAM III), one stellar occultation instrument (GOMOS) and one limb sounder (OSIRIS). The results indicate that the ACE imager profiles are of good quality in the upper troposphere/lower stratosphere, although the aerosol extinction for the visible channel at 525 nm contains a significant negative bias at higher altitudes, while the relative differences indicate that ACE profiles are almost always too high at 1020 nm. Both problems are probably related to ACE imager instrumental issues.

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Global distribution of upper tropospheric formic acid from the ACE-FTS

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-8039-2009 ◽

2009 ◽

Vol 9 (20) ◽

pp. 8039-8047 ◽

Cited By ~ 37

Author(s):

G. González Abad ◽

P. F. Bernath ◽

C. D. Boone ◽

S. D. McLeod ◽

G. L. Manney ◽

...

Keyword(s):

Fourier Transform ◽

Formic Acid ◽

Atmospheric Chemistry ◽

South American ◽

Fourier Transform Spectrometer ◽

Vegetation Growth ◽

Solar Occultation ◽

The Fourier Transform ◽

Chemistry Experiment ◽

Seasonal Dependence

Abstract. We present the first near global upper tropospheric distribution of formic acid (HCOOH) observed from space using solar occultation measurements from the Fourier transform spectrometer (FTS) on board the Atmospheric Chemistry Experiment (ACE) satellite. Using a new set of spectroscopic line parameters recently published for formic acid by Vander Auwera et al. (2007) and Perrin and Vander Auwera (2007), we have retrieved the concentrations of HCOOH between 5 km and the tropopause for ACE-FTS observations from February 2004 to September 2007. We observe a significant seasonal dependence for the HCOOH concentrations related to vegetation growth and biomass burning. We estimate an emission ratio of 0.0051±0.0015 for HCOOH relative to CO for tropical South American fires using a selected set of data for September 2004. Results from the balloon-borne MkIV Fourier transform spectrometer are also presented and compared with the ACE measurements.

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Balloon-borne radiometer measurement of Northern Hemisphere mid-latitude stratospheric HNO<sub>3</sub> profiles spanning 12 years

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-11561-2007 ◽

2007 ◽

Vol 7 (4) ◽

pp. 11561-11586 ◽

Cited By ~ 1

Author(s):

M. Toohey ◽

B. M. Quine ◽

K. Strong ◽

P. F. Bernath ◽

C. D. Boone ◽

...

Keyword(s):

Northern Hemisphere ◽

Atmospheric Chemistry ◽

Thermal Emission ◽

Emission Spectra ◽

Late Summer ◽

Radiative Properties ◽

Mixing Ratios ◽

Retrieval Technique ◽

Chemistry Experiment ◽

Radiometer Measurement

Abstract. Low-resolution atmospheric thermal emission spectra collected by balloon-borne radiometers over the time span of 1990–2002 are used to retrieve vertical profiles of HNO3, CFC-11 and CFC-12 volume mixing ratios between approximately 10 and 35 km altitude. All of the data analyzed have been collected from launches from a Northern Hemisphere mid-latitude site, during late summer, when stratospheric dynamic variability is at a minimum. The retrieval technique incorporates detailed forward modeling of the instrument and the radiative properties of the atmosphere, and obtains a best fit between modeled and measured spectra through a combination of onion-peeling and global optimization steps. The retrieved HNO3 profiles are consistent over the 12-year period, and are consistent with recent measurements by the Atmospheric Chemistry Experiment-Fourier transform spectrometer satellite instrument. This suggests that, to within the errors of the 1990 measurements, there has been no significant change in the HNO3 summer mid-latitude profile.

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Global carbon tetrachloride distributions obtained from the Atmospheric Chemistry Experiment (ACE)

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-7449-2009 ◽

2009 ◽

Vol 9 (19) ◽

pp. 7449-7459 ◽

Cited By ~ 22

Author(s):

N. D. C. Allen ◽

P. F. Bernath ◽

C. D. Boone ◽

M. P. Chipperfield ◽

D. Fu ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Atmospheric Chemistry ◽

Vertical Gradient ◽

Transport Models ◽

Zonal Distribution ◽

Solar Occultation ◽

Chemistry Experiment ◽

Global Carbon ◽

Temporal Coverage ◽

Good Agreement

Abstract. The first study of the global atmospheric distribution of carbon tetrachloride (CCl4), as a function of altitude and latitude, was performed using solar occultation measurements obtained by the Atmospheric Chemistry Experiment (ACE) mission using Fourier transform spectroscopy. A total of 8703 profile measurements were taken in the upper troposphere and lower stratosphere between February 2004 and August 2007. The zonal distribution of carbon tetrachloride displays a slight hemispheric asymmetry and decreasing concentration with increasing altitude at all latitudes. Maximum carbon tetrachloride concentrations are situated below 10 km in altitude with VMR (Volume Mixing Ratio) values of 100–130 ppt (parts per trillion). The highest concentrations are located about the Equator and at mid-latitudes, particularly for latitudes in heavily industrialised regions (20–45° N), with values declining towards the poles. Global distributions obtained from ACE were compared with predictions from three chemistry transport models showing good agreement in terms of the vertical gradient despite an overall offset. The ACE dataset gives unique global and temporal coverage of carbon tetrachloride and its transport through the atmosphere. An estimated lifetime for carbon tetrachloride of 34±5 years was determined through correlation with CFC-11.

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ACE-FTS observations of acetonitrile in the lower stratosphere

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-7405-2013 ◽

2013 ◽

Vol 13 (15) ◽

pp. 7405-7413 ◽

Cited By ~ 12

Author(s):

J. J. Harrison ◽

P. F. Bernath

Keyword(s):

Remote Sensing ◽

Atmospheric Chemistry ◽

Satellite Remote Sensing ◽

Lower Stratosphere ◽

Measurement Noise ◽

Fourier Transform Spectrometer ◽

Mixing Ratio ◽

Solar Occultation ◽

Retrieval Scheme ◽

Chemistry Experiment

Abstract. This work reports the first infrared satellite remote-sensing measurements of acetonitrile (CH3CN) in the Earth's atmosphere using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) between 2004 and 2011. The retrieval scheme uses new quantitative laboratory spectroscopic measurements of acetonitrile (Harrison and Bernath, 2012). Although individual ACE-FTS profile measurements are dominated by measurement noise, median profiles in 10° latitude bins show a steady decline in volume mixing ratio from ~150 ppt (parts per trillion) at 11.5 km to < 40 ppt at 25.5–29.5 km. These new measurements agree well with the scant available air- and balloon-borne data in the lower stratosphere. An acetonitrile stratospheric lifetime of 73 ± 20 yr has been determined.

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Validation of MIPAS IMK/IAA methane profiles

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-5565-2015 ◽

2015 ◽

Vol 8 (6) ◽

pp. 5565-5590 ◽

Cited By ~ 5

Author(s):

A. Laeng ◽

J. Plieninger ◽

T. von Clarmann ◽

U. Grabowski ◽

G. Stiller ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Michelson Interferometer ◽

Mixing Ratios ◽

Solar Occultation ◽

Time Period ◽

Measurement Mode ◽

High Bias ◽

Scanning Imaging ◽

The University ◽

Satellite Instruments

Abstract. The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was an infra-red (IR) limb emission spectrometer on the Envisat platform. It measured during day and night, pole-to-pole, over an altitude range from 6 to 70 km in nominal mode and up to 170 km in special modes, depending on the measurement mode, producing more than 1000 profiles day−1. We present the results of a validation study of methane version V5R_CH4_222 retrieved with the IMK/IAA MIPAS scientific level 2 processor. The level 1 spectra are provided by ESA, the version 5 was used. The time period covered corresponds to the period when MIPAS measured at reduced spectral resolution, i.e. 2005–2012. The comparison with satellite instruments includes the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the HALogen Occultation Experiment (HALOE), the Solar Occultation For Ice Experiment (SOFIE) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). Furthermore, comparisons with MkIV balloon-borne solar occultation measurements and with air sampling measurements performed by the University of Frankfurt are presented. The validation activities include bias determination, in selected cases, assessment of histograms and comparison of corresponding climatologies. Above 50 km altitude, MIPAS methane mixing ratios agree within 3% with ACE-FTS and SOFIE. Between 30 and 40 km an agreement within 3% with SCIAMACHY has been found. In the middle stratosphere, there is no clear indication of a MIPAS bias since comparisons with various instruments contradict each other. In the lower stratosphere (below about 25–30 km) MIPAS CH4 is biased high with respect to satellite instruments, and the most likely estimate of this bias is 14%. However, in the comparison with CH4 data obtained from cryosampler measurements, there is no evidence of a MIPAS high bias between 20 and 25 km altitude. Precision validation is performed on collocated MIPAS-MIPAS pairs and suggests a slight underestimation of its errors by a factor of 1.2. A parametric model consisting of constant, linear, QBO and several sine and cosine terms with different periods has been fitted to the temporal variation of differences of stratospheric CH4 measurements by MIPAS and ACE-FTS for all 10° latitude/1–2 km altitude bins. Only few significant drifts can be calculated, due to the lack of data. Significant drifts with respect to ACE-FTS tend to have higher absolute values in the Northern Hemisphere, have no pronounced tendency in the sign, and do not exceed 0.2 ppmv per decade in absolute value.

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Validation of ACE-FTS v2.2 methane profiles from the upper troposphere to lower mesosphere

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-17975-2007 ◽

2007 ◽

Vol 7 (6) ◽

pp. 17975-18014 ◽

Cited By ~ 2

Author(s):

M. De Mazière ◽

C. Vigouroux ◽

P. F. Bernath ◽

P. Baron ◽

T. Blumenstock ◽

...

Keyword(s):

Fourier Transform ◽

Atmospheric Chemistry ◽

Lower Stratosphere ◽

Remote Sensing Data ◽

Upper Troposphere ◽

Solar Occultation ◽

Systematic Uncertainties ◽

Comparison Results ◽

Key Species ◽

Chemistry Experiment

Abstract. The ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transform Spectrometer) solar occultation instrument that was launched onboard the Canadian SCISAT-1 satellite in August 2003 is measuring vertical profiles from the upper troposphere to the lower mesosphere for a large number of atmospheric constituents. Methane is one of the key species. The version v2.2 data of the ACE-FTS CH4 data have been compared to correlative satellite, balloon-borne and ground-based Fourier transform infrared remote sensing data to assess their quality. The comparison results indicate that the accuracy of the data is within 10% in the upper troposphere – lower stratosphere, and within 25% in the middle and higher stratosphere up to the lower mesosphere (<60 km). The observed differences are generally consistent with reported systematic uncertainties. ACE-FTS is also shown to reproduce the variability of methane in the stratosphere and lower mesosphere.

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Balloon-borne radiometer measurements of Northern Hemisphere mid-latitude stratospheric HNO<sub>3</sub> profiles spanning 12 years

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-6075-2007 ◽

2007 ◽

Vol 7 (23) ◽

pp. 6075-6084 ◽

Cited By ~ 2

Author(s):

M. Toohey ◽

B. M. Quine ◽

K. Strong ◽

P. F. Bernath ◽

C. D. Boone ◽

...

Keyword(s):

Northern Hemisphere ◽

Atmospheric Chemistry ◽

Thermal Emission ◽

Emission Spectra ◽

Late Summer ◽

Radiative Properties ◽

Mixing Ratios ◽

Retrieval Technique ◽

Chemistry Experiment

Abstract. Low-resolution atmospheric thermal emission spectra collected by balloon-borne radiometers over the time span of 1990–2002 are used to retrieve vertical profiles of HNO3, CFC-11 and CFC-12 volume mixing ratios between approximately 10 and 35 km altitude. All of the data analyzed have been collected from launches from a Northern Hemisphere mid-latitude site, during late summer, when stratospheric dynamic variability is at a minimum. The retrieval technique incorporates detailed forward modeling of the instrument and the radiative properties of the atmosphere, and obtains a best fit between modeled and measured spectra through a combination of onion-peeling and optimization steps. The retrieved HNO3 profiles are consistent over the 12-year period, and are consistent with recent measurements by the Atmospheric Chemistry Experiment-Fourier transform spectrometer satellite instrument. We therefore find no evidence of long-term changes in the HNO3 summer mid-latitude profile, although the uncertainty of our measurements precludes a conclusive trend analysis.

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