scholarly journals Sensitivity study of the instrumental temperature corrections on Brewer total ozone column measurements

2018 ◽  
Vol 11 (6) ◽  
pp. 3323-3337 ◽  
Author(s):  
Alberto Berjón ◽  
Alberto Redondas ◽  
Meelis-Mait Sildoja ◽  
Saulius Nevas ◽  
Keith Wilson ◽  
...  

Abstract. The instrumental temperature corrections to be applied to the ozone measurements by the Brewer spectrophotometers are derived from the irradiance measurements of internal halogen lamps in the instruments. These characterizations of the Brewer spectrophotometers can be carried out within a thermal chamber, varying the temperature from −5 to +45 ∘C, or during field measurements, making use of the natural change in ambient temperature. However, the internal light source used to determine the thermal sensitivity of the instrument could be affected in both methods by the temperature variations as well, which may affect the determination of the temperature coefficients. In order to validate the standard procedures for determining Brewer's temperature coefficients, two independent experiments using both external light sources and the internal halogen lamps have been performed within the ATMOZ Project. The results clearly show that the traditional methodology based on the internal halogen lamps is not sensitive to the temperature-caused changes in the spectrum of the internal light source. The three methodologies yielded equivalents results, with differences in total ozone column below 0.08 % for a mean diurnal temperature variation of 10 ∘C.

2017 ◽  
Author(s):  
Alberto Berjón ◽  
Alberto Redondas ◽  
Meelis-Mait Sildoja ◽  
Saulius Nevas ◽  
Keith Wilson ◽  
...  

Abstract. The instrumental temperature correction to be applied to the ozone measurements by the Brewer spectrophotometers is derived from measurements of the irradiance from an internal halogen lamp in the instrument. These characterisations of the Brewer instruments can be carried out within a thermal chamber, varying the temperature from −5 °C to +45 °C, or during field measurements, making use of the natural change in ambient temperature. However, the internal light source used to determine the thermal sensitivity of the instrument could be affected in both methods by the temperature variations as well, which may affect the determination of the temperature coefficients. In order to validate the standard procedures for determining Brewer's temperature coefficients, two independent experiments using both external light sources and the internal lamps have been performed within the ATMOZ Project. The results clearly show that the traditional methodology based on the internal lamps is not affected by possible temperature effects on the internal lamps. The three methodologies yielded equivalents results, with differences in total ozone column below 0.08 % for a mean diurnal temperature variation of 10 °C.


2015 ◽  
Vol 8 (5) ◽  
pp. 4917-4971
Author(s):  
A. Wassmann ◽  
T. Borsdorff ◽  
J. M. J. aan de Brugh ◽  
O. P. Hasekamp ◽  
I. Aben ◽  
...  

Abstract. In this work we present an extensive sensitivity study of retrieved total ozone columns from clear sky Global Ozone Monitoring Experiment 2 (GOME-2) measurements between 325 and 335nm which are corrected for instrument degradation. Employing an algorithm based on the scaling of a reference ozone profile with the extension to analytically calculate total column averaging kernels, allows us to investigate the impact of the choice of the reference profile on the retrieved total ozone column, since it represents a regularization of the retrieval. It introduces an error to the retrieved column with respect to the true column typically in the order of 1% depending on the reference scaling profile. However, a proper interpretation of the retrieved column using the total column averaging kernel avoids this error, which is demonstrated by a validation of GOME-2 total ozone columns with collocated ozonesonde and ground-based total ozone column measurements. Globally, we report a bias of 0.1% and a SD of 2.5% for 647 collocations with ground-based and ozonesonde measurements at different geolocations in the period of 2007 to 2010. Futhermore, an extended validation solely based on ground-based observations and a strict cloud filtering shows that the use of pseudo spherical scalar radiative transfer is fully sufficient for the purpose of this retrieval. Polarization of light by atmospheric scattering affects the retrieval accuracy only marginally and thus can be ignored. Finally, we study the effect of instrument degradation on the retrieved total ozone columns for the first four years of GOME-2 observations and discuss the efficiency of the proposed radiometric correction.


2021 ◽  
Vol 13 (8) ◽  
pp. 1594
Author(s):  
Songkang Kim ◽  
Sang-Jong Park ◽  
Hana Lee ◽  
Dha Hyun Ahn ◽  
Yeonjin Jung ◽  
...  

The ground-based ozone observation instrument, Brewer spectrophotometer (Brewer), was used to evaluate the quality of the total ozone column (TOC) produced by multiple polar-orbit satellite measurements at three stations in Antarctica (King Sejong, Jang Bogo, and Zhongshan stations). While all satellite TOCs showed high correlations with Brewer TOCs (R = ~0.8 to 0.9), there are some TOC differences among satellite data in austral spring, which is mainly attributed to the bias of Atmospheric Infrared Sounder (AIRS) TOC. The quality of satellite TOCs is consistent between Level 2 and 3 data, implying that “which satellite TOC is used” can induce larger uncertainty than “which spatial resolution is used” for the investigation of the Antarctic TOC pattern. Additionally, the quality of satellite TOC is regionally different (e.g., OMI TOC is a little higher at the King Sejong station, but lower at the Zhongshan station than the Brewer TOC). Thus, it seems necessary to consider the difference of multiple satellite data for better assessing the spatiotemporal pattern of Antarctic TOC.


1998 ◽  
Vol 22 (11) ◽  
pp. 1501-1504
Author(s):  
A.J.M Piters ◽  
P.F Levelt ◽  
M.A.F Allaart ◽  
H.M Kelder

2020 ◽  
Author(s):  
Javer A. Barrera ◽  
Rafael P. Fernandez ◽  
Fernando Iglesias-Suarez ◽  
Carlos A. Cuevas ◽  
Jean-Francois Lamarque ◽  
...  

Abstract. Biogenic very short-lived bromine (VSLBr) represents, nowadays, ~ 25 % of the total stratospheric bromine loading. Owing to their much shorter lifetime compared to anthropogenic long-lived bromine (LLBr, e.g., halons) and chlorine (LLCl, e.g., chlorofluorocarbons) substances, the impact of VSLBr on ozone peaks at the extratropical lowermost stratosphere, a key climatic and radiative atmospheric region. Here we present a modelling study of the evolution of stratospheric ozone and its chemical losses in extra-polar regions during the 21st century, under two different scenarios: considering and neglecting the additional stratospheric injection of 5 ppt biogenic VSLBr naturally released from the ocean. Our analysis shows that the inclusion of VSLBr result in a realistic stratospheric bromine loading and improves the quantitative 1980–2015 model-satellite agreement of total ozone column (TOC) in the mid-latitudes. We show that the overall ozone response to VSLBr within the mid-latitudes follows the stratospheric abundances evolution of long-lived inorganic chlorine and bromine throughout the 21st century. Additional ozone losses due to VSLBr are maximised during the present-day period (1990–2010), with TOC differences of −8 DU (−3 %) and −5.5 DU (−2 %) for the southern (SH-ML) and northern (NH-ML) mid-latitudes, respectively. Moreover, the projected TOC differences at the end of the 21st century are at least half of the values found for the present-day period. In the tropics, a small (


2016 ◽  
Vol 5 (1) ◽  
pp. 229-239 ◽  
Author(s):  
Tomi Karppinen ◽  
Kaisa Lakkala ◽  
Juha M. Karhu ◽  
Pauli Heikkinen ◽  
Rigel Kivi ◽  
...  

Abstract. Brewer total ozone column measurements started in Sodankylä in May 1988, 9 months after the signing of The Montreal Protocol. The Brewer instrument has been well maintained and frequently calibrated since then to produce a high-quality ozone time series now spanning more than 25 years. The data have now been uniformly reprocessed between 1988 and 2014. The quality of the data has been assured by automatic data rejection rules as well as by manual checking. Daily mean values calculated from the highest-quality direct sun measurements are available 77 % of time with up to 75 measurements per day on clear days. Zenith sky measurements fill another 14 % of the time series and winter months are sparsely covered by moon measurements. The time series provides information to survey the evolution of Arctic ozone layer and can be used as a reference point for assessing other total ozone column measurement practices.


2013 ◽  
Vol 58 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Boyan Petkov ◽  
Vito Vitale ◽  
Claudio Tomasi ◽  
Mauro Mazzola ◽  
Christian Lanconelli ◽  
...  

2012 ◽  
Vol 5 (9) ◽  
pp. 2169-2181 ◽  
Author(s):  
M. E. Koukouli ◽  
D. S. Balis ◽  
D. Loyola ◽  
P. Valks ◽  
W. Zimmer ◽  
...  

Abstract. The main aim of the paper is to assess the consistency of five years of Global Ozone Monitoring Experiment-2/Metop-A [GOME-2] total ozone columns and the long-term total ozone satellite monitoring database already in existence through an extensive inter-comparison and validation exercise using as reference Brewer and Dobson ground-based measurements. The behaviour of the GOME-2 measurements is being weighed against that of GOME (1995–2011), Ozone Monitoring Experiment [OMI] (since 2004) and the Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY [SCIAMACHY] (since 2002) total ozone column products. Over the background truth of the ground-based measurements, the total ozone columns are inter-evaluated using a suite of established validation techniques; the GOME-2 time series follow the same patterns as those observed by the other satellite sensors. In particular, on average, GOME-2 data underestimate GOME data by about 0.80%, and underestimate SCIAMACHY data by 0.37% with no seasonal dependence of the differences between GOME-2, GOME and SCIAMACHY. The latter is expected since the three datasets are based on similar DOAS algorithms. This underestimation of GOME-2 is within the uncertainty of the reference data used in the comparisons. Compared to the OMI sensor, on average GOME-2 data underestimate OMI_DOAS (collection 3) data by 1.28%, without any significant seasonal dependence of the differences between them. The lack of seasonality might be expected since both the GOME data processor [GDP] 4.4 and OMI_DOAS are DOAS-type algorithms and both consider the variability of the stratospheric temperatures in their retrievals. Compared to the OMI_TOMS (collection 3) data, no bias was found. We hence conclude that the GOME-2 total ozone columns are well suitable to continue the long-term global total ozone record with the accuracy needed for climate monitoring studies.


Sign in / Sign up

Export Citation Format

Share Document