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Anja Guenther - One of the best experts on this subject based on the ideXlab platform.
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a Tethered Balloon ptrms sampling approach for surveying of landscape scale biogenic voc fluxes
Atmospheric Measurement Techniques, 2014Co-Authors: J. P. Greenberg, Anja Guenther, A. Turnipseed, R. Seco, X Jiang, Josep Peñuelas, Iolanda FilellaAbstract:Landscape-scale fluxes of biogenic gases were surveyed by deploying a 100 m Teflon tube attached to a Tethered Balloon as a sampling inlet for a fast-response proton-transfer-reaction mass spectrometer (PTRMS). Along with meteorological instruments deployed on the Tethered Balloon and a 3 m tripod and outputs from a regional weather model, these observations were used to estimate landscape-scale biogenic volatile organic compound fluxes with two micrometeorological techniques: mixed layer vari- ance and surface layer gradients. This highly mobile sam- pling system was deployed at four field sites near Barcelona to estimate landscape-scale biogenic volatile organic com- pound (BVOC) emission factors in a relatively short period (3 weeks). The two micrometeorological techniques were compared with emissions predicted with a biogenic emission model us- ing site-specific emission factors and land-cover character- istics for all four sites. The methods agreed within the un- certainty of the techniques in most cases, even though the locations had considerable heterogeneity in species distri- bution and complex terrain. Considering the wide range in reported BVOC emission factors for individual vegetation species (more than an order of magnitude), this temporally short and inexpensive flux estimation technique may be use- ful for constraining BVOC emission factors used as model inputs.
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A Tethered-Balloon PTRMS sampling approach for rapid surveying of landscape-scale biogenic VOC fluxes
Atmospheric Measurement Techniques Discussions, 2014Co-Authors: J. P. Greenberg, Jordi Sardans, Anja Guenther, A. Turnipseed, R. Seco, M. Estiraste, Roma Ogaya, X Jiang, Iolanda Filella, Joan LlusiàAbstract:Abstract. To survey landscape-scale fluxes of biogenic gases, a 100 m Teflon tube was attached to a Tethered Balloon as a sampling inlet for a fast response Proton Transfer Reaction Mass Spectrometer (PTRMS). Along with meteorological instruments deployed on the Tethered Balloon and at 3 m and outputs from a regional weather model, these observations were used to estimate landscape scale biogenic volatile organic compound fluxes with two micrometeorological techniques: mixed layer variance and surface layer gradients. This highly mobile sampling system was deployed at four field sites near Barcelona to estimate landscape-scale BVOC emission factors in a relatively short period (3 weeks). The two micrometeorological techniques agreed within the uncertainty of the flux measurements at all four sites even though the locations had considerable heterogeneity in species distribution and complex terrain. The observed fluxes were significantly different than emissions predicted with an emission model using site-specific emission factors and land-cover characteristics. Considering the wide range in reported BVOC emission factors of VOCs for individual vegetation species (more than an order of magnitude), this flux estimation technique is useful for constraining BVOC emission factors used as model inputs.
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Tethered Balloon-based soundings of ozone, aerosols, and solar radiation near Mexico City during MIRAGE-MEX
Atmospheric Environment, 2009Co-Authors: Jim Greenberg, Anja Guenther, A. TurnipseedAbstract:Atmospheric Environment 43 (2009) 2672–2677 Contents lists available at ScienceDirect Atmospheric Environment journal homepage: www.elsevier.com/locate/atmosenv Short communication Tethered Balloon-based soundings of ozone, aerosols, and solar radiation near Mexico City during MIRAGE-MEX J.P. Greenberg * , A.B. Guenther, A. Turnipseed National Center for Atmospheric Research, Boulder, CO 80307, USA a r t i c l e i n f o a b s t r a c t Article history: Received 17 December 2008 Received in revised form 6 February 2009 Accepted 8 February 2009 A Tethered Balloon sampling system was used to measure vertical profiles of ozone, particles, and solar radiation in the atmospheric boundary layer on the northern edge of Mexico City, in March 2006 as part of the Megacity Impact on Regional and Global Environment-Mexico experiment. Several commercial sensors, designed for surface applications, were deployed on a Tethered Balloon platform. Profiles indicate that for these 3 scalars the boundary layer (surface up to 700 m) was well mixed in the period 10:00–16:00 LST. Good agreement was observed for median surface and Balloon ozone and particle number concentrations. For most profiles, the surface deposition of ozone was not significant compared to median profile concentrations. Particle number concentration (0.3, 0.5, 1.0 and 5.0 m m) also showed little variation with attitude. Radiatprofiles showed a monotonic increase in diffuse radiation from the maximum altitude of profiles to the surface. Consequently, it was inferred that surface measurements of these likely were representative of lower boundary layer values during this time period. O 2009 Elsevier Ltd. All rights reserved. Keywords: Tethered Balloon Boundary layer Megacity Ozone Radiation Particles 1. Introduction The MIRAGE (Megacity Impact on Regional and Global Envi- ronment)-MEX field campaign (March 2006) was designed to examine the chemical and physical transformations of gases and aerosols in the polluted outflow from Mexico City. The campaign included observations from ground stations, aircraft, and satellites. (An overview of the experiment is given in Molina et al., 2008). Surface measurements were made at three primary sites: central Mexico City (T0, Instituto Mexicano de Petroleo), the Technical University of Tecamac (T1), approximately 35 km NW of T0, and Rancho de Bisnaga (T2), approximately 70 km from T0. The sites were selected to characterize polluted MC air as it aged in transit from its source (arbitrarily set at T0). The Balloon–platform profiles presented here are from the T1 site (19N42.184, 98W59.917, 2270 m asl) from 13 to 28 March 2006. The primary objective of the Tethered Balloon study was to deter- mine if surface measurements accurately reflected concentrations in the boundary layer, so that ground based data might be extended to characterize to the atmospheric boundary layer analysis. Vertical profiles of several variables (ozone, particles, and direct and diffuse * Corresponding author. National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307, USA. Tel.: þ1 303 497 1454; fax: þ1 303 497 1400. E-mail address: greenber@ucar.edu (J.P. Greenberg). 1352-2310/$ – see front matter O 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.atmosenv.2009.02.019 solar radiation) were made to illustrate mixing from the surface to the maximum Balloon height (usually between 400 and 700 m above ground level). 2. Experiment details 2.1. Instrumentation Extensive details of Tethered Balloon profiling in the atmo- spheric boundary layer have been provided previously (Greenberg et al., 1999; Greenberg and Guenther, 2002). Several commercial lightweight sensors were deployed on the Balloon platform. Ozone was measured by a UV absorption ozone analyzer (2B Technologies, Boulder, CO, 2.1 kg); a glass fiber filter was placed on the inlet to prevent interference of dust in the optical cell. Ten second average data are reported for each profile. The relative standard deviation of 1 min averaged data was determined experimentally to be approximately 1.3% at approximately 70 ppb. An optical particle counter (Abacus, Particle Measurement Systems, Boulder, CO, 1 kg) was also deployed. Particles numbers were counted for discrete 0.3, 0.5, 1 and 5 m m sizes; 45 s average number concentrations are reported. The reported collection efficiency is approximately 20% for 0.3 m m particles. Total (global), direct (total minus diffuse) and diffuse radiation were measured using Sunshine Sensor, Model BF3 (Delta-T Devices, Ltd., Cambridge, UK, 0.5 kg). This detector has a sensor array which requires no shadow band and need not be
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Tethered Balloon measurements of biogenic vocs in the atmospheric boundary layer
Atmospheric Environment, 1999Co-Authors: J. P. Greenberg, Anja Guenther, P R Zimmerman, W Baugh, Chris Geron, Kenneth J Davis, Detlev Helmig, Lee KlingerAbstract:Biogenic volatile organic compounds (BVOCs) were measured on Tethered Balloon platforms in 11 deployments between 1985 and 1996. A series of Balloon sampling packages have been used to describe boundary layer dynamics, BVOC distribution, chemical transformations of BVOCs, and to estimate BVOC emission rates from terrestrial vegetation. Measurements indicated a slow decrease of concentration for BVOCs with altitude in the mixed layer when sampling times were greater than average convective turnover time; surface layer concentrations were more variable because of proximity to various emission sources in the smaller surface layer footprint. Mixed layer concentrations of isoprene remained fairly constant in the middle of the day, in contrast to canopy-level isoprene concentrations, which continued to increase until early evening. Daytime emissions, which increase with temperature and light, appear to be balanced by changes in entrainment and oxidation. Daytime measurements of methacrolein and methyl vinyl ketone, reaction products of the atmospheric oxidation of isoprene, showed fairly constant ratio to each other with altitude throughout the mixed layer. BVOC emission flux estimates using Balloon measurements and from the extrapolation of leaf level emissions to the landscape scale were in good agreement.
Detlev Helmig - One of the best experts on this subject based on the ideXlab platform.
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evaluation of ozone measurements from a Tethered Balloon sampling platform at south pole station in december 2003
Atmospheric Environment, 2008Co-Authors: B J Johnson, Detlev Helmig, Samuel J OltmansAbstract:Abstract Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500 m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.2±1.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17 m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of ∼4–6 m s−1) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at ∼0.3 m s−1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.7±0.8 ppbv lower than the long-line sampling method from eight profiles.
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Comparison of Ozone Measurements From a Tethered Balloon Sampling Platform at South Pole Station in December, 2003
2004Co-Authors: B J Johnson, Samuel J Oltmans, Detlev HelmigAbstract:Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.271.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of 4–6m s ) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at 0.3m s 1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.770.8 ppbv lower than the long-line sampling method from eight profiles. r 2007 Elsevier Ltd. All rights reserved.
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Tethered Balloon measurements of biogenic vocs in the atmospheric boundary layer
Atmospheric Environment, 1999Co-Authors: J. P. Greenberg, Anja Guenther, P R Zimmerman, W Baugh, Chris Geron, Kenneth J Davis, Detlev Helmig, Lee KlingerAbstract:Biogenic volatile organic compounds (BVOCs) were measured on Tethered Balloon platforms in 11 deployments between 1985 and 1996. A series of Balloon sampling packages have been used to describe boundary layer dynamics, BVOC distribution, chemical transformations of BVOCs, and to estimate BVOC emission rates from terrestrial vegetation. Measurements indicated a slow decrease of concentration for BVOCs with altitude in the mixed layer when sampling times were greater than average convective turnover time; surface layer concentrations were more variable because of proximity to various emission sources in the smaller surface layer footprint. Mixed layer concentrations of isoprene remained fairly constant in the middle of the day, in contrast to canopy-level isoprene concentrations, which continued to increase until early evening. Daytime emissions, which increase with temperature and light, appear to be balanced by changes in entrainment and oxidation. Daytime measurements of methacrolein and methyl vinyl ketone, reaction products of the atmospheric oxidation of isoprene, showed fairly constant ratio to each other with altitude throughout the mixed layer. BVOC emission flux estimates using Balloon measurements and from the extrapolation of leaf level emissions to the landscape scale were in good agreement.
Samuel J Oltmans - One of the best experts on this subject based on the ideXlab platform.
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evaluation of ozone measurements from a Tethered Balloon sampling platform at south pole station in december 2003
Atmospheric Environment, 2008Co-Authors: B J Johnson, Detlev Helmig, Samuel J OltmansAbstract:Abstract Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500 m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.2±1.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17 m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of ∼4–6 m s−1) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at ∼0.3 m s−1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.7±0.8 ppbv lower than the long-line sampling method from eight profiles.
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Comparison of Ozone Measurements From a Tethered Balloon Sampling Platform at South Pole Station in December, 2003
2004Co-Authors: B J Johnson, Samuel J Oltmans, Detlev HelmigAbstract:Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.271.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of 4–6m s ) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at 0.3m s 1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.770.8 ppbv lower than the long-line sampling method from eight profiles. r 2007 Elsevier Ltd. All rights reserved.
Qingyan Fu - One of the best experts on this subject based on the ideXlab platform.
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three dimensional analysis of ozone and pm2 5 distributions obtained by observations of Tethered Balloon and unmanned aerial vehicle in shanghai china
Stochastic Environmental Research and Risk Assessment, 2018Co-Authors: Xiaobing Li, Qingyan Fu, Qingchang Lu, Zhongren Peng, Bai Li, Dongfang Wang, Xiaoming Hu, Chao Li, Dongsheng WangAbstract:A lightweight unmanned aerial vehicle (UAV) and a Tethered Balloon platform were jointly used to investigate three-dimensional distributions of ozone and PM2.5 concentrations within the lower troposphere (1000 m) at a localized coastal area in Shanghai, China. Eight Tethered Balloon soundings and three UAV flights were conducted on May 25, 2016. Generalized additive models (GAMs) were used to quantitatively describe the relationships between air pollutants and other obtained parameters. Field observations showed that large variations were captured both in the vertical and horizontal distributions of ozone and PM2.5 concentrations. Significant stratified layers of ozone and PM2.5 concentrations as well as wind directions were observed throughout the day. Estimated bulk Richardson numbers indicate that the vertical mixing of air masses within the lower troposphere were heavily suppressed throughout the day, leading to much higher concentrations of ozone and PM2.5 in the planetary boundary layer (PBL). The NO and NO2 concentrations in the experimental field were much lower than that in the urban area of Shanghai and demonstrated totally different vertical distribution patterns from that of ozone and PM2.5. This indicates that aged air masses of different sources were transported to the experimental field at different heights. Results derived from the GAMs showed that the aggregate impact of the selected variables for the vertical variations can explain 94.3% of the variance in ozone and 94.5% in PM2.5. Air temperature, relative humidity and atmospheric pressure had the strongest effects on the variations of ozone and PM2.5. As for the horizontal variations, the GAMs can explain 56.3% of the variance in ozone and 57.6% in PM2.5. The strongest effect on ozone was related to air temperature, while PM2.5 was related to relative humidity. The output of GAMs also implied that fine aerosol particles were in the stage of growth in the experimental field, which is different from ozone (aged air parcels of ozone). Geographical parameters influenced the horizontal variations of ozone and PM2.5 concentrations by changing underlying surface types. The differences of thermodynamic properties between land and sea resulted in quick changes of PBL height, air temperature and dew point over the coastal area, which was linked to the extent of vertical mixing at different locations. The results of GAMs can be used to analyze the sources and formation mechanisms of ozone and PM2.5 pollutions at a localized area.
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Tethered Balloon based particle number concentration and size distribution vertical profiles within the lower troposphere of shanghai
Atmospheric Environment, 2017Co-Authors: Dongfang Wang, Qinggen Bian, Yusen Duan, Mengfei Zhao, Qingyan FuAbstract:Abstract A Tethered Balloon-based measurement campaign of particle number concentration (PNC) and particle number size distribution (PNSD) in the size range of 15.7–661.2 nm was conducted within the lower troposphere of 1000 m in Shanghai, a Chinese megacity, during December of 2015. The meteorological conditions, PNC, and PNSD were synchronously measured at the ground-based station as well as by the Tethered Balloon. On ground level, the 88.2 nm particles were found to have the highest PNC. The Pearson correlation analysis based on the ground level data showed NO 2 had a strong correlation with PNC. The synchronous measurement of PNC and PNSD at the ground station and on the Tethered Balloon showed that the 15.7–200 nm particles had higher PNC on ground level, but the PNC of 200–661.2 nm particles was higher at 400 m. One haze event (Dec 22nd-Dec 23rd) was selected for detailed discussion on the variation of vertical profiles of PNSD and PNC. The vertical distribution of characteristics of PNC and PNSD were observed and compared. Results indicated that the highest MaxDm (the diameter with the highest PNC) during those three launches all appeared at a high altitude, usually above 300 m. Compared to the clean days, the relatively bigger MaxDm at each height in the haze days also indicated regional transport of pollutants might contribute to more to that haze event.
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Tethered Balloon based black carbon profiles within the lower troposphere of shanghai in the 2013 east china smog
Atmospheric Environment, 2015Co-Authors: Juan Li, Qinggen Bian, Yusen Duan, Qingyan Fu, Yihua Zhang, Shenghsiang Wang, Dongfang Wang, Kan Huang, Wen Yang, Joshua S FuAbstract:Abstract A Tethered Balloon-based field campaign was launched for the vertical observation of air pollutants within the lower troposphere of 1000 m for the first time over a Chinese megacity, Shanghai in December of 2013. A custom-designed instrumentation platform for Tethered Balloon observation and ground-based observation synchronously operated for the measurement of same meteorological parameters and typical air pollutants. One episodic event (December 13) was selected with specific focus on particulate black carbon, a short-lived climate forcer with strong warming effect. Diurnal variation of the mixing layer height showed very shallow boundary of less than 300 m in early morning and night due to nocturnal inversion while extended boundary of more than 1000 m from noon to afternoon. Wind profiles showed relatively stagnant synoptic condition in the morning, frequent shifts between upward and downward motion at noon and in the afternoon, and dominant downward motion with sea breeze in the evening. Characteristics of black carbon vertical profiles during four different periods of a day were analyzed and compared. In the morning, surface BC concentration averaged as high as 20 μg/m 3 due to intense traffic emissions from the morning rush hours and unfavorable meteorological conditions. A strong gradient of BC concentrations with altitude was observed from the ground to the top of boundary layer at around 250–370 m. BC gradients turned much smaller above the boundary layer. BC profiles measured during noon and afternoon were the least dependent on heights. The largely extended boundary layer with strong vertical convection was responsible for a well mixing of BC particles in the whole measured column. BC profiles were similar between the early-evening and late-evening phases. The lower troposphere was divided into two stratified air layers with contrasted BC vertical distributions. Profiles at night showed strong gradients from the relatively high surface concentrations to low concentrations near the top of the boundary layer around 200 m. Above the boundary layer, BC increased with altitudes and reached a maximum at the top of 1000 m. Prevailing sea breeze within the boundary layer was mainly responsible for the quick cleanup of BC in the lower altitudes. In contrast, continental outflow via regional transport was the major cause of the enhanced BC aloft. This study provides a first insight of the black carbon vertical profiles over Eastern China, which will have significant implications for narrowing the gaps between the source emissions and observations as well as improving estimations of BC radiative forcing and regional climate.
B J Johnson - One of the best experts on this subject based on the ideXlab platform.
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evaluation of ozone measurements from a Tethered Balloon sampling platform at south pole station in december 2003
Atmospheric Environment, 2008Co-Authors: B J Johnson, Detlev Helmig, Samuel J OltmansAbstract:Abstract Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500 m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.2±1.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17 m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of ∼4–6 m s−1) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at ∼0.3 m s−1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.7±0.8 ppbv lower than the long-line sampling method from eight profiles.
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Comparison of Ozone Measurements From a Tethered Balloon Sampling Platform at South Pole Station in December, 2003
2004Co-Authors: B J Johnson, Samuel J Oltmans, Detlev HelmigAbstract:Vertical boundary-layer ozone profiles were measured from a Tethered Balloon platform during the 2003 Antarctic Tropospheric Chemistry Investigation (ANTCI) at South Pole Station, Antarctica. Electrochemical concentration cell (ECC) ozonesondes were used in obtaining 128 ascent and descent profile measurements to about 500m height during 13–30 December 2003. Various data checks and intercomparisons were done to confirm the accuracy of the ozonesondes. The ozonesondes compared well to a surface ozone ultra-violet (UV) absorption monitor located next to the tether Balloon site. During the 18-day period, ozonesonde measurement checks at the surface averaged 0.271.0 ppbv higher than the continuous ozone measurements under ambient concentrations ranging from 18 to 51 ppbv. This agreement was also consistent when compared to the nearby NOAA UV-monitor sampling at 17m above ground level during well-mixed conditions near the surface. In addition to the single ECC sonde profiles, five dual ECC ozonesondes were run on the tether platform. Four release Balloon-borne ozonesondes were also launched during the project. Under very sharp ozone gradient events, the release ozonesonde (with a rise rate of 4–6m s ) passed through the gradient layer too quickly to capture the detail as measured by the controlled tethersonde at 0.3m s 1 ascent/descent rate. Another method of ozone profiling was also done utilizing the UV monitor at the tether site and a 135-m-long Teflon sampling line with a sampling inlet mounted to and raised with the Tethered Balloon. The ECC ozonesonde averaged about 0.770.8 ppbv lower than the long-line sampling method from eight profiles. r 2007 Elsevier Ltd. All rights reserved.