Global Atmospheric Sampling Program: Prospects for Establishing a Tropospheric Ozone Budget from Commercial Aircraft Data

2009 ◽  
pp. 479-479-12 ◽  
Author(s):  
PD Falconer
Keyword(s):  
Tropospheric Ozone ◽  
Commercial Aircraft ◽  
Sampling Program ◽  
Atmospheric Sampling ◽  
Aircraft Data

scholarly journals 3-D evaluation of tropospheric ozone simulations by an ensemble of regional Chemistry Transport Model

2011 ◽  
Vol 11 (10) ◽  
pp. 28797-28849 ◽  
Author(s):  
D. Zyryanov ◽  
G. Foret ◽  
M. Eremenko ◽  
M. Beekmann ◽  
J.-P. Cammas ◽  
...  
Keyword(s):  
Boundary Conditions ◽  
Tropospheric Ozone ◽  
Transport Model ◽  
Lower Troposphere ◽  
Systematic Bias ◽  
Free Troposphere ◽  
Commercial Aircraft ◽  
Data Set ◽  
Vertical Ozone

Abstract. A detailed 3-D evaluation of an ensemble of five regional CTM's and one global CTM with focus on free tropospheric ozone over Europe is presented. It is performed over a summer period (June to August 2008) in the context of the GEMS-RAQ project. A data set of about 400 vertical ozone profiles from balloon soundings and commercial aircraft at 11 different locations is used for model evaluation, in addition to satellite measurements with the infrared nadir IASI sounder showing largest sensitivity to free tropospheric ozone. In the free troposphere, models using the same top and boundary conditions from MOZART-IFS exhibit a systematic negative bias with respect to observed profiles of about −20%. RMSE values are constantly growing with altitude, from 22% to 32% to 53%, respectively for 0–2 km, 2–8 km and 8–10 km height ranges. Lowest correlation is found in the free troposphere, with minimum coefficients (R) between 0.2 to 0.45 near 8 km, as compared to 0.7 near the surface and similar values around 10 km. Use of hourly instead of monthly chemical boundary conditions generally improves the model skill. Lower tropospheric 0–6 km partial ozone columns derived from IASI show a clear North-South gradient over Europe, which is qualitatively reproduced by the models. Also the temporal variability showing decreasing ozone concentrations in the lower troposphere (0–6 km columns) during summer is well catched by models even if systematic bias remains (the value of the bias being also controlled by the type of BC used). A multi-day case study of a through with low tropopause was conducted and showed that both IASI and models were able to resolve strong horizontal gradients of middle and upper tropospheric ozone occurring in the vicinity of an upper tropospheric frontal zone.

scholarly journals Long-term changes in UT/LS ozone between the late 1970s and the 1990s deduced from the GASP and MOZAIC aircraft programs and from ozonesondes

2009 ◽  
Vol 9 (1) ◽  
pp. 2435-2499 ◽  
Author(s):  
C. Schnadt Poberaj ◽  
J. Staehelin ◽  
D. Brunner ◽  
V. Thouret ◽  
H. De Backer ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Data Sets ◽  
Air Masses ◽  
Long Term Changes ◽  
Eastern Usa ◽  
Research Aircraft ◽  
Atmospheric Sampling ◽  
Unites States ◽  
Aircraft Data

Abstract. We present ozone measurements of the Global Atmospheric Sampling Program (GASP) performed from four commercial and one research aircraft in the late 1970s to compare them with respective measurements of the ongoing MOZAIC project. Climatologies of UT/LS ozone were built using the aircraft data sets (1975–1979 and 1994–2001), and long-term changes between the 1970s and 1990s were derived by comparison. The data were binned relative to the dynamical tropopause to separate between UT and LS air masses. LS data were analysed using equivalent latitudes. In the UT, pronounced increases are found over the Middle East and South Asia in the spring and summer seasons. Increases are also found over Japan, Europe, and the eastern parts of the Unites States depending on season. LS ozone over northern mid- and high latitudes was found to be lower in the 1990s compared to the 1970s in all seasons of the year. In addition, a comparison with long-term changes deduced from ozonesondes is presented. An altitude offset was applied to the sonde data to account for the slow response time of the ozone sensors. The early 1970s European Brewer-Mast (BM) sonde data agree with GASP within the range of uncertainty (UT) or measured slightly less ozone (LS). In contrast, the 1990s BM sensors show consistently and significantly higher UT/LS ozone values than MOZAIC. This unequal behaviour of aircraft/sonde comparisons in the 1970s and 1990s leads to differences in the estimated long-term changes over Europe: while the comparison between GASP and MOZAIC indicates ozone changes of −5% to 10% over Europe, the sondes suggest a much larger increase of 10%–35% depending on station and season, although statistical significance is not conclusive due to data sample limitations. In contrast to the BM sondes, the Electrochemical Cell (ECC) sonde at Wallops Island, USA, measured higher UT ozone than both GASP and MOZAIC. Hence, long-term changes from GASP/MOZAIC agree within the range of uncertainty with the changes deduced from Wallops Island. The comparison of GASP with BM and ECC ozonesonde data over Europe and the eastern USA, respectively, corroborates earlier studies stating that early BM instruments measured less ozone than ECC sensor by 10–25%.

scholarly journals Long-term changes in UT/LS ozone between the late 1970s and the 1990s deduced from the GASP and MOZAIC aircraft programs and from ozonesondes

2009 ◽  
Vol 9 (14) ◽  
pp. 5343-5369 ◽  
Author(s):  
C. Schnadt Poberaj ◽  
J. Staehelin ◽  
D. Brunner ◽  
V. Thouret ◽  
H. De Backer ◽  
...  
Keyword(s):  
Electrochemical Cell ◽  
Statistical Significance ◽  
The United States ◽  
Data Sets ◽  
Air Masses ◽  
Long Term Changes ◽  
Research Aircraft ◽  
Atmospheric Sampling ◽  
Aircraft Data

Abstract. We present ozone measurements of the Global Atmospheric Sampling Program (GASP) performed from four commercial and one research aircraft in the late 1970s to compare them with respective measurements of the ongoing MOZAIC project. Multi-annual averages of UT/LS ozone were built using the aircraft data sets (1975–1979 and 1994–2001), and long-term changes between the 1970s and 1990s were derived by comparison. The data were binned relative to the dynamical tropopause to separate between UT and LS air masses. LS data were analysed using equivalent latitudes. In the UT, pronounced increases of 20–40% are found over the Middle East and South Asia in the spring and summer seasons. Increases are also found over Japan, Europe, and the eastern parts of the United States depending on season. LS ozone over northern mid- and high latitudes was found to be lower in the 1990s compared to the 1970s in all seasons of the year. In addition, a comparison with long-term changes deduced from ozonesondes is presented. The early 1970s European Brewer-Mast (BM) sonde data agree with GASP within the range of uncertainty (UT) or measured slightly less ozone (LS). In contrast, the 1990s BM sensors show consistently and significantly higher UT/LS ozone values than MOZAIC. This unequal behaviour of aircraft/sonde comparisons in the 1970s and 1990s leads to differences in the estimated long-term changes over Europe: while the comparison between GASP and MOZAIC indicates ozone changes of −5% to 10% over Europe, the sondes suggest a much larger increase of 10%–35% depending on station and season, although statistical significance is not conclusive due to data sample limitations. In contrast to the BM sondes, the Electrochemical Cell (ECC) sonde at Wallops Island, USA, measured higher UT ozone than both GASP and MOZAIC. Hence, long-term changes from GASP/MOZAIC agree within the range of uncertainty with the changes deduced from Wallops Island.

scholarly journals Development of a balloon-borne instrument for CO<sub>2</sub> vertical profile observations in the troposphere

2019 ◽  
Vol 12 (10) ◽  
pp. 5639-5653
Author(s):  
Mai Ouchi ◽  
Yutaka Matsumi ◽  
Tomoki Nakayama ◽  
Kensaku Shimizu ◽  
Takehiko Sawada ◽  
...  
Keyword(s):  
Vertical Profile ◽  
Field Experiments ◽  
Co2 Concentration ◽  
Observation System ◽  
Vertical Profiles ◽  
Commercial Aircraft ◽  
Observation Network ◽  
The Difference ◽  
Carbon Dioxide Co2 ◽  
Aircraft Data

Abstract. A novel, practical observation system for measuring tropospheric carbon dioxide (CO2) concentrations using a non-dispersive infrared analyzer carried by a small helium-filled balloon (CO2 sonde) has been developed for the first time. Vertical profiles of atmospheric CO2 can be measured with a 240–400 m altitude resolution through regular onboard calibrations using two different CO2 standard gases. The standard deviations (1σ) of the measured mole fractions in the laboratory experiments using a vacuum chamber at a temperature of 298 K were approximately 0.6 ppm at 1010 hPa and 1.2 ppm at 250 hPa. Two CO2 vertical profile data obtained using the CO2 sondes, which were launched on 31 January and 3 February 2011 at Moriya, were compared with the chartered aircraft data on the same days and the commercial aircraft data obtained by the Comprehensive Observation Network for TRace gases by Airliner (COTRAIL) program on the same day (31 January) and 1 d before (2 February). The difference between the CO2 sonde data and these four sets of in situ aircraft data (over the range of each balloon altitude ±100 m) up to the altitude of 7 km was 0.6±1.2 ppm (average ±1σ). In field experiments, the CO2 sonde detected an increase in CO2 concentration in an urban area and a decrease in a forested area near the surface. The CO2 sonde was shown to be a useful instrument for observing and monitoring the vertical profiles of CO2 concentration in the troposphere.

scholarly journals 3-D evaluation of tropospheric ozone simulations by an ensemble of regional Chemistry Transport Model

2012 ◽  
Vol 12 (7) ◽  
pp. 3219-3240 ◽  
Author(s):  
D. Zyryanov ◽  
G. Foret ◽  
M. Eremenko ◽  
M. Beekmann ◽  
J.-P. Cammas ◽  
...  
Keyword(s):  
Boundary Conditions ◽  
Tropospheric Ozone ◽  
Transport Model ◽  
Lower Troposphere ◽  
Systematic Bias ◽  
Commercial Aircraft ◽  
Data Set ◽  
Middle Troposphere ◽  
Vertical Ozone

Abstract. A detailed 3-D evaluation of an ensemble of five regional Chemistry Transport Models (RCTM) and one global CTM with focus on free tropospheric ozone over Europe is presented. It is performed over a summer period (June to August 2008) in the context of the GEMS-RAQ project. A data set of about 400 vertical ozone profiles from balloon soundings and commercial aircraft at 11 different locations is used for model evaluation, in addition to satellite measurements with the infrared nadir sounder (IASI) showing largest sensitivity to free tropospheric ozone. In the middle troposphere, the four regional models using the same top and boundary conditions from IFS-MOZART exhibit a systematic negative bias with respect to observed profiles of about −20%. Root Mean Square Error (RMSE) values are constantly growing with altitude, from 22% to 32% to 53%, respectively for 0–2 km, 2–8 km and 8–10 km height ranges. Lowest correlation is found in the middle troposphere, with minimum coefficients (R) between 0.2 to 0.45 near 8 km, as compared to 0.7 near the surface and similar values around 10 km. A sensitivity test made with the CHIMERE mode also shows that using hourly instead of monthly chemical boundary conditions generally improves the model skill (i.e. improve RMSE and correlation). Lower tropospheric 0–6 km partial ozone columns derived from IASI show a clear North-South gradient over Europe, which is qualitatively reproduced by the models. Also the temporal variability showing decreasing ozone concentrations in the lower troposphere (0–6 km columns) during summer is well reproduced by models even if systematic bias remains (the value of the bias being also controlled by the type of used boundary conditions). A multi-day case study of a trough with low tropopause was conducted and showed that both IASI and models were able to resolve strong horizontal gradients of middle and upper tropospheric ozone occurring in the vicinity of an upper tropospheric frontal zone.

scholarly journals Aircraft observations since the 1990s reveal increases of tropospheric ozone at multiple locations across the Northern Hemisphere

2020 ◽  
Vol 6 (34) ◽  
pp. eaba8272 ◽  
Author(s):  
Audrey Gaudel ◽  
Owen R. Cooper ◽  
Kai-Lan Chang ◽  
Ilann Bourgeois ◽  
Jerry R. Ziemke ◽  
...  
Keyword(s):  
Northern Hemisphere ◽  
Temporal Variability ◽  
Tropospheric Ozone ◽  
Radiative Forcing ◽  
Monitoring Network ◽  
Spatial And Temporal Variability ◽  
Commercial Aircraft ◽  
Aircraft Observations ◽  
Ozone Precursor ◽  
Satellite Product

Tropospheric ozone is an important greenhouse gas, is detrimental to human health and crop and ecosystem productivity, and controls the oxidizing capacity of the troposphere. Because of its high spatial and temporal variability and limited observations, quantifying net tropospheric ozone changes across the Northern Hemisphere on time scales of two decades had not been possible. Here, we show, using newly available observations from an extensive commercial aircraft monitoring network, that tropospheric ozone has increased above 11 regions of the Northern Hemisphere since the mid-1990s, consistent with the OMI/MLS satellite product. The net result of shifting anthropogenic ozone precursor emissions has led to an increase of ozone and its radiative forcing above all 11 study regions of the Northern Hemisphere, despite NOx emission reductions at midlatitudes.

scholarly journals Tropospheric ozone variability during the East Asian summer monsoon as observed by satellite (IASI), aircraft (MOZAIC) and ground stations

2016 ◽  
Vol 16 (16) ◽  
pp. 10489-10500 ◽  
Author(s):  
Sarah Safieddine ◽  
Anne Boynard ◽  
Nan Hao ◽  
Fuxiang Huang ◽  
Lili Wang ◽  
...  
Keyword(s):  
Summer Monsoon ◽  
Tropospheric Ozone ◽  
East Asian Summer Monsoon ◽  
Asian Summer Monsoon ◽  
East Asian ◽  
The Other ◽  
The North ◽  
Asian Summer ◽  
Tropospheric O3 ◽  
Aircraft Data

Abstract. Satellite measurements from the thermal Infrared Atmospheric Sounding Interferometer (IASI), aircraft data from the MOZAIC/IAGOS project, as well as observations from ground-based stations, are used to assess the tropospheric ozone (O3) variability during the East Asian Summer Monsoon (EASM). Six years 2008–2013 of IASI data analysis reveals the ability of the instrument to detect the onset and the progression of the monsoon seen by a decrease in the tropospheric 0–6 km O3 column due to the EASM, and to reproduce this decrease from one year to the other. The year-to-year variability is found to be mainly dependent on meteorology. Focusing on the period of May-August 2011, taken as an example year, IASI data show clear inverse relationship between tropospheric 0–6 km O3 on one hand and meteorological parameters such as cloud cover, relative humidity and wind speed, on the other hand. Aircraft data from the MOZAIC/IAGOS project for the EASM of 2008–2013 are used to validate the IASI data and to assess the effect of the monsoon on the vertical distribution of the tropospheric O3 at different locations. Results show good agreement with a correlation coefficient of 0.73 (12 %) between the 0–6 km O3 column derived from IASI and aircraft data. IASI captures very well the inter-annual variation of tropospheric O3 observed by the aircraft data over the studied domain. Analysis of vertical profiles of the aircraft data shows a decrease in the tropospheric O3 that is more important in the free troposphere than in the boundary layer and at 10–20° N than elsewhere. Ground station data at different locations in India and China show a spatiotemporal dependence on meteorology during the monsoon, with a decrease up to 22 ppbv in Hyderabad, and up to 5 ppbv in the North China Plain.

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