Uncertainty analysis of total ozone derived from direct solar irradiance spectra in the presence of unknown spectral deviations

Abstract. We demonstrate the use of a Monte Carlo model to estimate the uncertainties in total ozone column (TOC) derived from ground-based direct solar spectral irradiance measurements. The model estimates the effects of possible systematic spectral deviations in the solar irradiance spectra on the uncertainties in retrieved TOC. The model is tested with spectral data measured with three different spectroradiometers at an intercomparison campaign of the research project “Traceability for atmospheric total column ozone” at Izaña, Tenerife on 17 September 2016. The TOC values derived at local noon have expanded uncertainties of 1.3 % (3.6 DU) for a high-end scanning spectroradiometer, 1.5 % (4.4 DU) for a high-end array spectroradiometer, and 4.7 % (13.3 DU) for a roughly adopted instrument based on commercially available components and an array spectroradiometer when correlations are taken into account. When neglecting the effects of systematic spectral deviations, the uncertainties reduce by a factor of 3. The TOC results of all devices have good agreement with each other, within the uncertainties, and with the reference values of the order of 282 DU during the analysed day, measured with Brewer spectrophotometer #183.

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Monte Carlo method for determining uncertainty of total ozone derived from direct solar irradiance spectra: Application to Izaña results

10.5194/amt-2017-403 ◽

2018 ◽

Cited By ~ 1

Author(s):

Anna Vaskuri ◽

Petri Kärhä ◽

Luca Egli ◽

Julian Gröbner ◽

Erkki Ikonen

Keyword(s):

Monte Carlo ◽

Total Ozone ◽

Monte Carlo Model ◽

Spectral Irradiance ◽

Total Column Ozone ◽

Solar Spectral Irradiance ◽

Irradiance Data ◽

Column Ozone ◽

Ozone Column ◽

Total Column

Abstract. We demonstrate a Monte Carlo model to calculate the uncertainties of total ozone column, TOC, derived from ground-based directional solar spectral irradiance measurements. The model takes into account effects that correlations in the spectral irradiance data may have on the results. The model is tested with spectral data measured with three different spectroradiometers at an intercomparison campaign of the research project Traceability for atmospheric total column ozone at Izaña, Tenerife on 17 September 2016. The TOC values derived at noon have expanded uncertainties of 1.3 % for a high-end scanning spectroradiometer, 1.3 % for a high-end array spectroradiometer, and 3.3 % for a roughly adopted instrument based on commercially available components and an array spectroradiometer. The level of TOC measured with reference Brewer spectrophotometer #183 is of the order of 282 DU during the analysed day and in agreement with the results of the two former instruments.

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Comparison of profile total ozone from SBUV(v8.6) with GOME-type and ground-based total ozone for 16-yr period (1996 to 2011)

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-10081-2013 ◽

2013 ◽

Vol 6 (6) ◽

pp. 10081-10115 ◽

Cited By ~ 1

Author(s):

E. W. Chiou ◽

P. K. Bhartia ◽

R. D. McPeters ◽

D. G. Loyola ◽

M. Coldewey-Egbers ◽

...

Keyword(s):

Strong Evidence ◽

Total Ozone ◽

Time Dependent ◽

Total Column Ozone ◽

Monthly Data ◽

Latitude Band ◽

Ozone Data ◽

Standard Deviations ◽

Column Ozone ◽

Total Column

Abstract. This paper describes the comparison of the variability of total column ozone inferred from the three independent multi-year data records, namely, (i) SBUV(v8.6) profile total ozone, (ii) GTO(GOME-Type total ozone), and (iii) Ground-based total ozone data records covering the 16-yr overlap period (March 1996 through June 2011). Analyses are conducted based on area weighted zonal means for (0–30° S), (0–30° N), (50–30° S), and (30–60° N). It has been found that on average, the differences in monthly zonal mean total ozone vary between −0.32 to 0.76 % and are well within 1%. For "GTO minus SBUV", the standard deviations and ranges (maximum minus minimum) of the differences regarding monthly zonal mean total ozone vary between 0.58 to 0.66% and 2.83 to 3.82% respectively, depending on the latitude band. The corresponding standard deviations and ranges regarding the differences in monthly zonal mean anomalies show values between 0.40 to 0.59% and 2.19 to 3.53%. The standard deviations and ranges of the differences "Ground-based minus SBUV" regarding both monthly zonal means and anomalies are larger by a factor of 1.4 to 2.9 in comparison to "GTO minus SBUV". The Ground-based zonal means, while show no systematic differences, demonstrate larger scattering of monthly data compared to satellite-based records. The differences in the scattering are significantly reduced if seasonal zonal averages are analyzed. The trends of the differences "GTO minus SBUV" and "Ground-based minus SBUV" are found to vary between −0.04 and 0.12% yr−1 (−0.11 and 0.31 DU yr−1). These negligibly small trends have provided strong evidence that there are no significant time dependent differences among these multi-year total ozone data records. Analyses of the deviations from pre-1980 level indicate that for the overlap period of 1996 to 2010, all three data records show gradual recovery at (30–60° N) from −5% in 1996 to −2% in 2010. The corresponding recovery at (50–30° S) is not as obvious until after 2006.

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Retrieval of ozone column content from airborne Sun photometer measurements during SOLVE II: comparison with coincident satellite and aircraft measurements

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-2035-2005 ◽

2005 ◽

Vol 5 (8) ◽

pp. 2035-2054 ◽

Cited By ~ 17

Author(s):

J. M. Livingston ◽

B. Schmid ◽

P. B. Russell ◽

J. A. Eilers ◽

R. W. Kolyer ◽

...

Keyword(s):

Research Center ◽

Total Column Ozone ◽

Solar Occultation ◽

Latitudinal Transect ◽

Validation Experiment ◽

Satellite Sensors ◽

Langley Research Center ◽

Column Ozone ◽

Ozone Column ◽

Total Column

Abstract. During the 2003 SAGE (Stratospheric Aerosol and Gas Experiment) III Ozone Loss and Validation Experiment (SOLVE) II, the fourteen-channel NASA Ames Airborne Tracking Sunphotometer (AATS-14) was mounted on the NASA DC-8 aircraft and measured spectra of total and aerosol optical depth (TOD and AOD) during the sunlit portions of eight science flights. Values of ozone column content above the aircraft have been derived from the AATS-14 measurements by using a linear least squares method that exploits the differential ozone absorption in the seven AATS-14 channels located within the Chappuis band. We compare AATS-14 columnar ozone retrievals with temporally and spatially near-coincident measurements acquired by the SAGE III and the Polar Ozone and Aerosol Measurement (POAM) III satellite sensors during four solar occultation events observed by each satellite. RMS differences are 19 DU (7% of the AATS value) for AATS-SAGE and 10 DU (3% of the AATS value) for AATS-POAM. In these checks of consistency between AATS-14 and SAGE III or POAM III ozone results, the AATS-14 analyses use airmass factors derived from the relative vertical profiles of ozone and aerosol extinction obtained by SAGE III or POAM III. We also compare AATS-14 ozone retrievals for measurements obtained during three DC-8 flights that included extended horizontal transects with total column ozone data acquired by the Total Ozone Mapping Spectrometer (TOMS) and the Global Ozone Monitoring Experiment (GOME) satellite sensors. To enable these comparisons, the amount of ozone in the column below the aircraft is estimated either by assuming a climatological model or by combining SAGE and/or POAM data with high resolution in-situ ozone measurements acquired by the NASA Langley Research Center chemiluminescent ozone sensor, FASTOZ, during the aircraft vertical profile at the start or end of each flight. Resultant total column ozone values agree with corresponding TOMS and GOME measurements to within 10-15 DU (~3%) for AATS data acquired during two flights - a longitudinal transect from Sweden to Greenland on 21 January, and a latitudinal transect from 47° N to 35° N on 6 February. For the round trip DC-8 latitudinal transect between 34° N and 22° N on 19-20 December 2002, resultant AATS-14 ozone retrievals plus below-aircraft ozone estimates yield a latitudinal gradient that is similar in shape to that observed by TOMS and GOME, but resultant AATS values exceed the corresponding satellite values by up to 30 DU at certain latitudes. These differences are unexplained, but they are attributed to spatial and temporal variability that was associated with the dynamics near the subtropical jet but was unresolved by the satellite sensors. For selected cases, we also compare AATS-14 ozone retrievals with values derived from coincident measurements by the other two DC-8 based solar occultation instruments: the National Center for Atmospheric Research Direct beam Irradiance Airborne Spectrometer (DIAS) and the NASA Langley Research Center Gas and Aerosol Monitoring System (GAMS). AATS and DIAS retrievals agree to within RMS differences of 1% of the AATS values for the 21 January and 19-20 December flights, and 2.3% for the 6 February flight. Corresponding AATS-GAMS RMS differences are ~1.5% for the 21 January flight; GAMS data were not compared for the 6 February flight and were not available for the 19-20 December flight. Line of sight ozone retrievals from coincident measurements obtained by the three DC-8 solar occultation instruments during the SAGE III solar occultation event on 24 January yield RMS differences of 2.1% for AATS-DIAS and 0.5% for AATS-GAMS.

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Adaption of an array spectroradiometer for total ozone column retrieval using direct solar irradiance measurements in the UV spectral range

10.5194/amt-2017-240 ◽

2017 ◽

Author(s):

Ralf Zuber ◽

Peter Sperfeld ◽

Stefan Riechelmann ◽

Saulius Nevas ◽

Meelis Sildoja ◽

...

Keyword(s):

Spectral Range ◽

Solar Irradiance ◽

Total Ozone ◽

Spectral Irradiance ◽

Stray Light ◽

Limiting Factor ◽

Total Ozone Column ◽

Reduction Methods ◽

Robust Measurements ◽

Ozone Column

Abstract. A compact array spectroradiometer technology that enables precise and robust measurements of UV spectral irradiance is presented. The spectroradiometer design allows various applications such as measurement of high-power UV lamps, risk assessment of sources and measurement of solar irradiance. We show that this technology can perform precise total ozone column (TOC) retrieval. The internal stray light, which is often the limiting factor for measurements in the UV spectral range and increases the uncertainty for TOC analysis significantly, is physically reduced so that no other stray light 15 reduction methods, such as mathematical corrections, are necessary. The instrument and its elaborate components have been extensively characterised at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. During an international total ozone measurement intercomparison at the Izaña observatory in Tenerife, the high-quality applicability of the instrument was verified with measurements of the direct solar irradiance and subsequent TOC evaluations based on the spectral data between 12 and 30 September 2016. The results showed deviations of less than 1.5 % to most other instruments in most 20 situations not exceeding 3 % compared to established TOC measurement systems such as Dobson or Brewer.

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OMI total column ozone: extending the long-term data record

Atmospheric Measurement Techniques ◽

10.5194/amt-8-4845-2015 ◽

2015 ◽

Vol 8 (11) ◽

pp. 4845-4850 ◽

Cited By ~ 37

Author(s):

R. D. McPeters ◽

S. Frith ◽

G. J. Labow

Keyword(s):

Cross Sections ◽

Total Ozone ◽

Retrieval Algorithm ◽

Data Set ◽

Total Column Ozone ◽

Ozone Data ◽

Combining Data ◽

Data Record ◽

Column Ozone ◽

Total Column

Abstract. The ozone data record from the Ozone Monitoring Instrument (OMI) onboard the NASA Earth Observing System (EOS) Aura satellite has proven to be very stable over the 10-plus years of operation. The OMI total column ozone processed through the Total Ozone Mapping Spectrometer (TOMS) ozone retrieval algorithm (version 8.5) has been compared with ground-based measurements and with ozone from a series of SBUV/2 (Solar Backscatter Ultraviolet) instruments. Comparison with an ensemble of Brewer–Dobson sites shows an absolute offset of about 1.5 % and almost no relative trend. Comparison with a merged ozone data set (MOD) created by combining data from a series of SBUV/2 instruments again shows an offset, of about 1 %, and a relative trend of less than 0.5 % over 10 years. The offset is mostly due to the use of the old Bass–Paur ozone cross sections in the OMI retrievals rather than the Brion–Daumont–Malicet cross sections that are now recommended. The bias in the Southern Hemisphere is smaller than that in the Northern Hemisphere, 0.9 % vs. 1.5 %, for reasons that are not completely understood. When OMI was compared with the European realization of a multi-instrument ozone time series, the GTO (GOME type Total Ozone) data set, there was a small trend of about −0.85 % decade−1. Since all the comparisons of OMI relative to other ozone measuring systems show relative trends that are less than 1 % decade−1, we conclude that the OMI total column ozone data are sufficiently stable that they can be used in studies of ozone trends.

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Solar Backscatter UV (SBUV) total ozone and profile algorithm

Atmospheric Measurement Techniques ◽

10.5194/amt-6-2533-2013 ◽

2013 ◽

Vol 6 (10) ◽

pp. 2533-2548 ◽

Cited By ~ 91

Author(s):

P. K. Bhartia ◽

R. D. McPeters ◽

L. E. Flynn ◽

S. Taylor ◽

N. A. Kramarova ◽

...

Keyword(s):

Cross Sections ◽

Total Ozone ◽

Lower Atmosphere ◽

Quasi Biennial Oscillation ◽

Total Column Ozone ◽

Best Estimate ◽

Current Algorithm ◽

Previous Algorithm ◽

Column Ozone ◽

Total Column

Abstract. We describe the algorithm that has been applied to develop a 42 yr record of total ozone and ozone profiles from eight Solar Backscatter UV (SBUV) instruments launched on NASA and NOAA satellites since April 1970. The Version 8 (V8) algorithm was released more than a decade ago and has been in use since then at NOAA to produce their operational ozone products. The current algorithm (V8.6) is basically the same as V8, except for updates to instrument calibration, incorporation of new ozone absorption cross-sections, and new ozone and cloud height climatologies. Since the V8 algorithm has been optimized for deriving monthly zonal mean (MZM) anomalies for ozone assessment and model comparisons, our emphasis in this paper is primarily on characterizing the sources of errors that are relevant for such studies. When data are analyzed this way the effect of some errors, such as vertical smoothing of short-term variability, and noise due to clouds and aerosols diminish in importance, while the importance of others, such as errors due to vertical smoothing of the quasi-biennial oscillation (QBO) and other periodic and aperiodic variations, become more important. With V8.6 zonal mean data we now provide smoothing kernels that can be used to compare anomalies in SBUV profile and partial ozone columns with models. In this paper we show how to use these kernels to compare SBUV data with Microwave Limb Sounder (MLS) ozone profiles. These kernels are particularly useful for comparisons in the lower stratosphere where SBUV profiles have poor vertical resolution but partial column ozone values have high accuracy. We also provide our best estimate of the smoothing errors associated with SBUV MZM profiles. Since smoothing errors are the largest source of uncertainty in these profiles, they can be treated as error bars in deriving interannual variability and trends using SBUV data and for comparing with other measurements. In the V8 and V8.6 algorithms we derive total column ozone by integrating the SBUV profiles, rather than from a separate set of wavelengths, as was done in previous algorithm versions. This allows us to extend the total ozone retrieval to 88° solar zenith angle (SZA). Since the quality of total column data is affected by reduced sensitivity to ozone in the lower atmosphere by cloud and Rayleigh attenuation, which gets worse with increasing SZA, we provide our best estimate of these errors, as well as the kernels that can be used to test the sensitivity of the derived columns to long-term changes in ozone in the lower atmosphere.

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Comparison of profile total ozone from SBUV (v8.6) with GOME-type and ground-based total ozone for a 16-year period (1996 to 2011)

Atmospheric Measurement Techniques ◽

10.5194/amt-7-1681-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 1681-1692 ◽

Cited By ~ 15

Author(s):

E. W. Chiou ◽

P. K. Bhartia ◽

R. D. McPeters ◽

D. G. Loyola ◽

M. Coldewey-Egbers ◽

...

Keyword(s):

Strong Evidence ◽

Total Ozone ◽

Gradual Increase ◽

Time Dependent ◽

Total Column Ozone ◽

Monthly Data ◽

Ozone Data ◽

Standard Deviations ◽

Column Ozone ◽

Total Column

Abstract. This paper describes the comparison of the variability of total column ozone inferred from the three independent multi-year data records, namely, (i) Solar Backscatter Ultraviolet Instrument (SBUV) v8.6 profile total ozone, (ii) GTO (GOME-type total ozone), and (iii) ground-based total ozone data records covering the 16-year overlap period (March 1996 through June 2011). Analyses are conducted based on area-weighted zonal means for 0–30° S, 0–30° N, 50–30° S, and 30–60° N. It has been found that, on average, the differences in monthly zonal mean total ozone vary between −0.3 and 0.8 % and are well within 1%. For GTO minus SBUV, the standard deviations and ranges (maximum minus minimum) of the differences regarding monthly zonal mean total ozone vary between 0.6–0.7% and 2.8–3.8% respectively, depending on the latitude band. The corresponding standard deviations and ranges regarding the differences in monthly zonal mean anomalies show values between 0.4–0.6% and 2.2–3.5%. The standard deviations and ranges of the differences ground-based minus SBUV regarding both monthly zonal means and anomalies are larger by a factor of 1.4–2.9 in comparison to GTO minus SBUV. The ground-based zonal means demonstrate larger scattering of monthly data compared to satellite-based records. The differences in the scattering are significantly reduced if seasonal zonal averages are analyzed. The trends of the differences GTO minus SBUV and ground-based minus SBUV are found to vary between −0.04 and 0.1% yr−1 (−0.1 and 0.3 DU yr−1). These negligibly small trends have provided strong evidence that there are no significant time-dependent differences among these multi-year total ozone data records. Analyses of the annual deviations from pre-1980 level indicate that, for the 15-year period of 1996 to 2010, all three data records show a gradual increase at 30–60° N from −5% in 1996 to −2% in 2010. In contrast, at 50–30° S and 30° S–30° N there has been a levelling off in the 15 years after 1996. The deviations inferred from GTO and SBUV show agreement within 1%, but a slight increase has been found in the differences during the period 1996–2010.

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Attribution of observed changes in stratospheric ozone and temperature

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-17341-2010 ◽

2010 ◽

Vol 10 (7) ◽

pp. 17341-17367

Author(s):

N. P. Gillett ◽

H. Akiyoshi ◽

S. Bekki ◽

V. Eyring ◽

R. Garcia ◽

...

Keyword(s):

Greenhouse Gases ◽

Total Ozone ◽

Climate Models ◽

Stratospheric Ozone ◽

Total Column Ozone ◽

Detection And Attribution ◽

Stratospheric Temperature ◽

Ozone Depleting Substances ◽

Column Ozone ◽

Total Column

Abstract. Three recently-completed sets of simulations of multiple chemistry-climate models with greenhouse gases only, with all anthropogenic forcings, and with anthropogenic and natural forcings, allow the causes of observed stratospheric changes to be quantitatively assessed using detection and attribution techniques. The total column ozone response to halogenated ozone depleting substances and to natural forcings is detectable and consistent in models and observations. However, the total ozone response to greenhouse gases in the models and observations appears to be inconsistent, which may be due to the models' inability to properly simulate tropospheric ozone changes. In the middle and upper stratosphere, simulated and observed SBUV/SAGE ozone changes are broadly consistent, and separate anthropogenic and natural responses are detectable in observations. The influence of ozone depleting substances and natural forcings can also be detected separately in observed lower stratospheric temperature, and the magnitudes of the simulated and observed responses to these forcings and to greenhouse gas changes are found to be consistent. In the mid and upper stratosphere the simulated natural and combined anthropogenic responses are detectable and consistent with observations, but the influences of greenhouse gases and ozone-depleting substances could not be separately detected in our analysis.

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On the relationship between total ozone and atmospheric dynamics and chemistry at mid-latitudes – Part 1: Statistical models and spatial fingerprints of atmospheric dynamics and chemistry

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-13161-2012 ◽

2012 ◽

Vol 12 (5) ◽

pp. 13161-13199 ◽

Cited By ~ 2

Author(s):

L. Frossard ◽

H. E. Rieder ◽

M. Ribatet ◽

J. Staehelin ◽

J. A. Maeder ◽

...

Keyword(s):

Solar Cycle ◽

Statistical Models ◽

Total Ozone ◽

Volcanic Eruptions ◽

Atmospheric Dynamics ◽

Quasi Biennial Oscillation ◽

Total Column Ozone ◽

Value Analysis ◽

Column Ozone ◽

Total Column

Abstract. We use models for mean and extreme values of total column ozone on spatial scales to analyze "fingerprints" of atmospheric dynamics and chemistry on long-term ozone changes at northern and southern mid-latitudes. The r-largest order statistics method is used for pointwise analysis of extreme events in low and high total ozone (termed ELOs and EHOs, respectively). For the corresponding mean value analysis a pointwise autoregressive moving average model (ARMA) is used. The statistical models include important atmospheric covariates to describe the dynamical and chemical state of the atmosphere: the solar cycle, the Quasi-Biennial Oscillation (QBO), ozone depleting substances (ODS) in terms of equivalent effective stratospheric chlorine (EESC), the North Atlantic Oscillation (NAO), the Antarctic Oscillation (AAO), the El~Niño/Southern Oscillation (ENSO), and aerosol load after the volcanic eruptions of El Chichón and Mt. Pinatubo. The influence of the individual covariates on mean and extreme levels in total column ozone is derived on a grid cell basis. The results show that "fingerprints", i.e., significant influence, of dynamical and chemical features are captured in both the "bulk" and the tails of the ozone distribution, respectively described by means and EHOs/ELOs. While results for the solar cycle, QBO and EESC are in good agreement with findings of earlier studies, unprecedented spatial fingerprints are retrieved for the dynamical covariates.

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Simulation of solar-cycle response in tropical total column ozone using SORCE irradiance

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-1867-2012 ◽

2012 ◽

Vol 12 (1) ◽

pp. 1867-1893 ◽

Cited By ~ 1

Author(s):

K.-F. Li ◽

X. Jiang ◽

M.-C. Liang ◽

Y. L. Yung

Keyword(s):

Solar Cycle ◽

Atmospheric Chemistry ◽

Southern Oscillation ◽

Spectral Irradiance ◽

Naval Research ◽

Tropical Region ◽

Total Column Ozone ◽

Model Input ◽

Column Ozone ◽

Total Column

Abstract. Total column ozone (XO3) abundance in Earth's atmosphere is intimately related to atmospheric chemistry and dynamics. Understanding the solar-cycle modulations of XO3 helps distinguish anthropogenic perturbations from natural variability during the ozone recovery. Here, the solar-cycle signal of tropical XO3 in the Whole Atmosphere Community Climate Model (WACCM) model has been examined using solar spectral irradiance (SSI) estimated from the Naval Research Laboratory (NRL) solar model and that from recent satellite measurements observed by the Solar Radiation and Climate Experiment (SORCE). Four experiments have been conducted with NRL/SORCE SSI and climatological/realistic sea surface temperatures and ice, and all other variability is fixed. In the tropical region 24° S–24° N, using the SORCE SSI as a model input leads to a solar-cycle response of ~5.4 DU/100F10.7, which is ~2 times of that obtained using NRL SSI. The results are slightly different in the presence of El Niño/Southern Oscillation (ENSO) when realistic SST/ice is used, but these differences are within the regression uncertainty of ~0.6 DU/100F10.7. The solar-cycle responses simulated using SORCE SSI agree with those obtained from the merged TOMS/SBUV satellite observations. Using NRL SSI as a model input results in solar-cycle responses that are closer to the ground-based observations, although the accuracy of the latter is limited by the number of stations in the tropics. In all model experiments, the tropical distribution of the solar-cycle response is constant to within ~0.5 DU/100F10.7, which is of the same order as the regression uncertainty. The spatial structures of the regression uncertainty are shown to be correlated with ENSO in the Pacific region. The solar-cycle response obtained using SORCE SSI implies a maximum change in lower stratospheric temperature of ~0.8 K. This may lead to significant impacts on the model solar-cycle responses in atmospheric circulation, precipitation and other hydrological variables that are important for the climate change.

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