Internal consistency of the IAGOS ozone and carbon monoxide measurements for the last 25 years

Abstract. The In-service Aircraft for a Global Observing System (IAGOS) is a European research infrastructure that equips the Airbus A340/330 with a system for monitoring atmospheric composition. The IAGOS instruments have three different configurations: IAGOS-Core, IAGOS – Measurement of Ozone and Water Vapor by Airbus In Service Aircraft (IAGOS-MOZAIC) and IAGOS – Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container (IAGOS-CARIBIC). Since 1994, there have been a total of 17 aircraft equipped. In this study, we perform an intercomparison of about 8000 landing and takeoff profiles to compare the O3 and CO measurements performed from these different configurations. The collocated profiles used in the study met various selection criteria. The first was a maximal 1 h time difference between an ascent or descent by two different aircraft at the same airport and the second was a selection based on the similarity of air masses based on the meteorological data acquired by the aircraft. We provide here an evaluation of the internal consistency of the O3 and CO measurements since 1994. For both O3 and CO, we find no drift in the bias amongst the different instrument units (six O3 and six CO IAGOS-MOZAIC instruments, nine IAGOS-Core Package1 and the two instruments used in the IAGOS-CARIBIC aircraft). This result gives us confidence that the entire IAGOS database can be treated as one continuous program and is therefore appropriate for studies of long-term trends.

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Internal consistency of the IAGOS ozone and carbon monoxide measurements for the last 25 years

10.5194/amt-2020-462 ◽

2020 ◽

Author(s):

Romain Blot ◽

Philippe Nedelec ◽

Damien Boulanger ◽

Pawel Wolff ◽

Bastien Sauvage ◽

...

Keyword(s):

Carbon Monoxide ◽

Data Base ◽

Internal Consistency ◽

Selection Criteria ◽

Meteorological Data ◽

Atmospheric Composition ◽

European Research ◽

Air Masses ◽

Long Term Trends

Abstract. The In-service Aircraft for a Global Observing System is a European research infrastructure that equips Airbus A340/330 with a system for monitoring atmospheric composition. The IAGOS instruments have three different configurations: IAGOS-CORE, IAGOS-MOZAIC and IAGOS-CARIBIC. Since 1994, there have been a total of 17 aircraft equipped. In this study, we perform an inter-comparison of about 8000 landing and take-off profiles to compare the O3 and CO measurements performed from these different configurations. The collocated profiles used in the study met various selection criteria. The first was a maximal 1 hour time difference between an ascent or descent by two different aircraft at the same airport and the second was a selection based on the similarity of air masses based on the meteorological data acquired by the aircraft. We provide here an evaluation of the internal consistency of the O3 and CO measurements since 1994. For both O3 and CO, we find no drift in the bias amongst the different instrument units (6 O3 and 6 CO IAGOS-MOZAIC instruments, 9 IAGOS-CORE Package 1 and the 2 instruments used in the IAGOS-CARIBIC aircraft). This results gives us confidence that the entire IAGOS data base can be treated as one continuous program, and is therefore appropriate for studies of long-term trends.

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Long term trends of methane, non methane hydrocarbons, and carbon monoxide in urban atmosphere

The Science of The Total Environment ◽

10.1016/j.scitotenv.2015.02.058 ◽

2015 ◽

Vol 518-519 ◽

pp. 595-604

Author(s):

Ezaz Ahmed ◽

Ki-Hyun Kim ◽

Eui-Chan Jeon ◽

Richard J.C. Brown

Keyword(s):

Carbon Monoxide ◽

Urban Atmosphere ◽

Long Term Trends

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Long-term trends in solar radiation and the associated climatic factors over China for 1961-2000

Annales Geophysicae ◽

10.5194/angeo-23-2425-2005 ◽

2005 ◽

Vol 23 (7) ◽

pp. 2425-2432 ◽

Cited By ~ 121

Author(s):

F. Liang ◽

X. A. Xia

Keyword(s):

Solar Radiation ◽

Climatic Factors ◽

Sunshine Duration ◽

Cloud Amount ◽

Atmospheric Composition ◽

Abrupt Decrease ◽

Radiative Processes ◽

Aerosol Loading ◽

Long Term Trends

Abstract. Long-term trends in downwelling solar irradiance and associated climatic factors over China are studied in the paper. Decreasing trends in global and direct radiation are observed over much of China. The largest decrease occurs in South and East China (east of about 100° E and south of about 40° N). The spatial pattern of observed trends in diffuse irradiance is complex and inhomogeneous. An intriguing aspect of trends in global and direct irradiance is the rather abrupt decrease in annual and seasonal mean values from 1978 onward. The decreasing trends in solar radiation in China did not persist into the 1990s. The spatial and temporal patterns of trends in sunshine duration are consistent with that of global and direct irradiance. A decreasing trend in rainy days is observed over much of China, which is in agreement with the secular trend in cloud amount. The fact that trends in cloud amount and solar radiation are quite similar suggests that the cloud amount is not the primary cause for the decrease in solar radiation. Visibility in the eastern part of China has deteriorated heavily as a result of the rapid increase in aerosol loading. The statistical analysis showed that atmospheric transmission under clear conditions decreased rapidly. These facts suggest that the rapid increase in aerosol loading should be one of the principle causes for the decrease in solar radiation. The observed diurnal temperature range decreases remarkably in China, which is closely related to the increase in aerosols. The effects of anthropogenic air pollutants on climate should be further studied and included in the simulation of climate and projection of climate scenario. Keywords. Atmospheric composition and structure (Aerosol and particles; General or miscellaneous) – Meteorology and atmospheric dynamics (Radiative processes)

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Long-term trends of surface ozone and its influencing factors at the Mt. Waliguan GAW station, China, Part 2: Variation mechanism and links to some climate indices

10.5194/acp-2017-483 ◽

2017 ◽

Author(s):

Wanyun Xu ◽

Xiaobin Xu ◽

Meiyun Lin ◽

Weili Lin ◽

Jie Tang ◽

...

Keyword(s):

Southeast Asia ◽

Trajectory Analysis ◽

Surface Ozone ◽

Eastern China ◽

Sunspot Cycle ◽

Anthropogenic Emissions ◽

Climate Indices ◽

Air Masses ◽

Long Term Trends

Abstract. Interannual variability and long-term trends of tropospheric ozone are both of environmental and climate concerns. Ozone measured at Mt. Waliguan Observatory (WLG, 3816 m asl) on the Tibetan Plateau over the period 19947ndash;2013 has increased significantly by 0.2–0.3 ppbv year-1 during spring and autumn, but shows a much smaller trend in winter and no significant trend in summer. Here we explore the factors driving the observed ozone changes at WLG using backward trajectory analysis, chemistry-climate model hindcast simulations (GFDL-AM3), a trajectory-mapped ozonesonde dataset and various climate indices. A stratospheric ozone tracer implemented in GFDL-AM3 indicates that stratosphere-to-troposphere transport (STT) can explain ~ 70 % of the observed springtime ozone increase at WLG, consistent with an increase in the NW air mass frequency inferred from the trajectory analysis. Enhanced STT associated with the strengthening of the mid-latitude jet stream contributes to the observed high-ozone anomalies at WLG during the springs of 1999 and 2012. During autumn, observations at WLG are more heavily influenced by polluted air masses originated from Southeast Asia than in the other seasons. Rising Asian anthropogenic emissions of ozone precursors is the key driver of increasing autumnal ozone observed at WLG, as supported by the GFDL-AM3 model with time-varying emissions, which captures the observed ozone increase (0.26 ± 0.11 ppbv year-1). AM3 simulates a greater ozone increase of 0.38 ± 0.11 ppbv year-1 at WLG in autumn under conditions with strong transport from Southeast Asia and shows no significant ozone trend in autumn when anthropogenic emissions are held constant in time. During summer, WLG is mostly influenced by easterly air masses but these trajectories do not extend to the polluted regions of eastern China and have decreased significantly over the last two decades, which likely explains why summertime ozone measured at WLG shows no significant trend despite ozone increases in Eastern China. Analysis of the Trajectory-mapped Ozonesonde dataset for the Stratosphere and Troposphere (TOST) and trajectory residence time reveals increases in direct ozone transport from the eastern sector during autumn, which adds to the autumnal ozone increase. We further examine the links of ozone variability at WLG to the QBO, the North Atlantic Oscillation (NAO), the East Asian summer monsoon (EASM) and the sunspot cycle. Our results suggest that the 2–3 year, 3–7 year and 11 year periodicities are linked to QBO, EASMI and NAO and the sunspot cycle, respectively. A multivariate regression analysis is performed to quantify the relative contributions of various factors to surface ozone concentrations at WLG. Through an observational and modelling analysis, this study demonstrates the complex relationships between surface ozone at remote locations and its dynamical and chemical influencing factors.

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Long-Term Isotope Records of Precipitation in Zagreb, Croatia

Water ◽

10.3390/w12010226 ◽

2020 ◽

Vol 12 (1) ◽

pp. 226 ◽

Cited By ~ 11

Author(s):

Ines Krajcar Bronić ◽

Jadranka Barešić ◽

Damir Borković ◽

Andreja Sironić ◽

Ivanka Lovrenčić Mikelić ◽

...

Keyword(s):

Meteoric Water ◽

Isotope Composition ◽

Eastern Mediterranean ◽

Meteorological Data ◽

Precipitation Amount ◽

Monthly Precipitation ◽

Air Masses ◽

Water Line ◽

Meteoric Water Line

The isotope composition of precipitation has been monitored in monthly precipitation at Zagreb, Croatia, since 1976. Here, we present a statistical analysis of available long-term isotope data (3H activity concentration, δ2H, δ18O, and deuterium excess) and compare them to basic meteorological data. The aim was to see whether isotope composition reflected observed climate changes in Zagreb: a significant increase in the annual air temperature and larger variations in the precipitation amount. Annual mean δ18O and δ2H values showed an increase of 0.017‰ and 0.14‰ per year, respectively, with larger differences in monthly mean values in the first half of the year than in the second half. Mean annual d-excess remained constant over the whole long-term period, with a tendency for monthly mean d-excess values to decrease in the first half of the year and increase in the second half due to the influence of air masses originating from the eastern Mediterranean. Changes in the stable isotope composition of precipitation thus resembled changes in the temperature, the circulation pattern of air masses, and the precipitation regime. A local meteoric water line was obtained using different regression methods, which did not result in significant differences between nonweighted and precipitation-weighted slope and intercept values. Deviations from the Global Meteoric Water Line GMWL (lower slopes and intercepts) were observed in two recent periods and could be explained by changes in climate parameters. The temperature gradient of δ18O was 0.33‰/°C. The tritium activity concentrations in precipitation showed slight decreases during the last two decades, and the mean A in the most recent period, 2012–2018, was 7.6 ± 0.8 Tritium Units (TU).

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Ozone, carbon monoxide and nitrogen oxides time series at four alpine GAW mountain stations in central Europe

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-12295-2010 ◽

2010 ◽

Vol 10 (24) ◽

pp. 12295-12316 ◽

Cited By ~ 78

Author(s):

S. Gilge ◽

C. Plass-Duelmer ◽

W. Fricke ◽

A. Kaiser ◽

L. Ries ◽

...

Keyword(s):

Carbon Monoxide ◽

Anthropogenic Impacts ◽

Vertical Mixing ◽

Atmospheric Composition ◽

Altitude Range ◽

Calibration Laboratory ◽

Central European ◽

Mixing Ratios ◽

Weekly Cycles

Abstract. Long-term, ground based in-situ observations of ozone (O3) and its precursor gases nitrogen dioxide (NO2) and carbon monoxide (CO) from the four sites Hohenpeissenberg and Zugspitze (D), Sonnblick (A) and Jungfraujoch (CH) are presented for the period 1995–2007. These Central European alpine mountain observatories cover an altitude range of roughly 1000 to 3500 m. Comparable analytical methods and common quality assurance (QA) procedures are used at all sites. For O3 and CO, calibration is linked to primary calibrations (O3) or CO standards provided by the Central Calibration Laboratory (CCL) at NOAA/ESRL. All stations have been audited by the World Calibration Centre (WCC) for CO and O3 (WCC-Empa; CH). Data from long-term measurements of NO2 and CO are only available from Hohenpeissenberg and Jungfraujoch. Both sites show slightly decreasing mixing ratios of the primarily emitted NO2 and the partly anthropogenically emitted CO between 1995 and 2007. The findings are generally consistent with shorter observation periods at Zugspitze and Sonnblick and thus are considered to represent regional changes in Central European atmospheric composition at this altitude range. Over the same period, 1995–2007, the O3 mixing ratios have slightly increased at three of the four sites independent of wind sector. Trends are often more pronounced in winter and less in summer; highest declines of NO2 and CO are observed in winter and the lowest in summer, whereas the strongest O3 increase was detected in winter and lowest or even decline in summer, respectively. Weekly cycles demonstrate anthropogenic impact at all elevations with enhanced NO2 on working days compared to weekends. Enhanced O3 values on working days indicating photochemical production from anthropogenic precursors are only observed in summer, whereas in all other seasons anti-correlation with NO2 was found due to reduced O3 values on working days. Trends are discussed with respect to anthropogenic impacts and vertical mixing. The observed trends for NO2 at the alpine mountain sites are less pronounced than trends estimated based on emission inventories.

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Carbon monoxide measurements onboard the CARIBIC passenger aircraft using UV resonance fluorescence

Atmospheric Measurement Techniques ◽

10.5194/amt-5-1753-2012 ◽

2012 ◽

Vol 5 (7) ◽

pp. 1753-1760 ◽

Cited By ~ 26

Author(s):

D. Scharffe ◽

F. Slemr ◽

C. A. M. Brenninkmeijer ◽

A. Zahn

Keyword(s):

Chemical Characterization ◽

Atmospheric Composition ◽

Quality Data ◽

Integration Time ◽

Resonance Fluorescence ◽

Air Masses ◽

Passenger Aircraft ◽

Instrument Reliability

Abstract. Goal of the project CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrumented Container) is to carry out regular and detailed observations of atmospheric composition (particles and gases) at cruising altitudes of passenger aircraft, i.e. at 9–12 km. Continuous, fast measurement of CO is indispensable for the chemical characterization of encountered air masses, for the detection of plumes of polluted air and for studying troposphere-stratosphere transport. CO is measured by a commercial resonance fluorescence UV instrument modified for the use onboard passenger aircraft. Modifications were necessary to optimize the instrument reliability allowing unattended operation for several days. The instrument has a precision of 1–2 ppbv at an integration time of 1 s. The response time to reach 63.2% signal strength is 2 s. We describe the modifications of the instrument, the experiences made during its operation since December 2004, the quality control of CO measurements onboard CARIBIC, and suggest a regular service routine that guarantees long-term high-quality data.

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Long-Term Trends of Carbon Monoxide Total Columnar Amount in Urban Areas and Background Regions: Ground- and Satellite-based Spectroscopic Measurements

Advances in Atmospheric Sciences ◽

10.1007/s00376-017-6327-8 ◽

2018 ◽

Vol 35 (7) ◽

pp. 785-795 ◽

Cited By ~ 6

Author(s):

Pucai Wang ◽

N. F. Elansky ◽

Yu. M. Timofeev ◽

Gengchen Wang ◽

G. S. Golitsyn ◽

...

Keyword(s):

Carbon Monoxide ◽

Urban Areas ◽

Spectroscopic Measurements ◽

Long Term Trends

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Evaluation of new laser spectrometer techniques for in-situ carbon monoxide measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-5-2555-2012 ◽

2012 ◽

Vol 5 (10) ◽

pp. 2555-2567 ◽

Cited By ~ 41

Author(s):

C. Zellweger ◽

M. Steinbacher ◽

B. Buchmann

Keyword(s):

Carbon Monoxide ◽

Measurement Techniques ◽

Field Measurements ◽

Current Data ◽

Atmospheric Composition ◽

Environmental Research ◽

Spectroscopic Techniques ◽

New Techniques

Abstract. Long-term time series of the atmospheric composition are essential for environmental research and thus require compatible, multi-decadal monitoring activities. The current data quality objectives of the World Meteorological Organization (WMO) for carbon monoxide (CO) in the atmosphere are very challenging to meet with the measurement techniques that have been used until recently. During the past few years, new spectroscopic techniques came to market with promising properties for trace gas analytics. The current study compares three instruments that have recently become commercially available (since 2011) with the best currently available technique (Vacuum UV Fluorescence) and provides a link to previous comparison studies. The instruments were investigated for their performance regarding repeatability, reproducibility, drift, temperature dependence, water vapour interference and linearity. Finally, all instruments were examined during a short measurement campaign to assess their applicability for long-term field measurements. It could be shown that the new techniques perform considerably better compared to previous techniques, although some issues, such as temperature influence and cross sensitivities, need further attention.

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