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Chen L, Zhang Q, Zhu M, Li G, Chang L, Xu Z, Zhang H, Wang Y, Zheng Y, Zhong S, Pan K, Zhao Y, Gao M, Zhang B. A convolutional neural network prediction model for aviation nitrogen oxides emissions throughout all flight phases. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172432. [PMID: 38615768 DOI: 10.1016/j.scitotenv.2024.172432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 03/08/2024] [Accepted: 04/10/2024] [Indexed: 04/16/2024]
Abstract
In recent years, there has been an increasing amount of research on nitrogen oxides (NOx) emissions, and the environmental impact of aviation NOx emissions at cruising altitudes has received widespread attention. NOx may play a crucial role in altering the composition of the atmosphere, particularly regarding ozone formation in the upper troposphere. At present, the ground emission database based on the landing and takeoff (LTO) cycle is more comprehensive, while high-altitude emission data is scarce due to the prohibitively high cost and the inevitable measurement uncertainty associated with in-flight sampling. Therefore, it is necessary to establish a comprehensive NOx emission database for the entire flight envelope, encompassing both ground and cruise phases. This will enable a thorough assessment of the impact of aviation NOx emissions on climate and air quality. In this study, a prediction model has been developed via convolutional neural network (CNN) technology. This model can predict the ground and cruise NOx emission index for turbofan engines and mixed turbofan engines fueled by either conventional aviation kerosene or sustainable aviation fuels (SAFs). The model utilizes data from the engine emission database (EEDB) released by the International Civil Aviation Organization (ICAO) and results obtained from several in-situ emission measurements conducted during ground and cruise phases. The model has been validated by comparing measured and predicted data, and the results demonstrate its high prediction accuracy for both the ground (R2 > 0.95) and cruise phases (R2 > 0.9). This surpasses traditional prediction models that rely on fuel flow rate, such as the Boeing Fuel Flow Method 2 (BFFM2). Furthermore, the model can predict NOx emissions from aircrafts burning SAFs with satisfactory accuracy, facilitating the development of a more complete and accurate aviation NOx emission inventory, which can serve as a basis for aviation environmental and climatic research. SYNOPSIS: The utilization of the ANOEPM-CNN offers a foundation for establishing more precise emission inventories, thereby reducing inaccuracies in assessing the impact of aviation NOx emissions on climate and air quality.
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Affiliation(s)
- Longfei Chen
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; International Innovation Institute, Beihang University, Hangzhou 311115, China; School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Qian Zhang
- International Innovation Institute, Beihang University, Hangzhou 311115, China; School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Meiyin Zhu
- International Innovation Institute, Beihang University, Hangzhou 311115, China.
| | - Guangze Li
- International Innovation Institute, Beihang University, Hangzhou 311115, China
| | - Liuyong Chang
- International Innovation Institute, Beihang University, Hangzhou 311115, China
| | - Zheng Xu
- International Innovation Institute, Beihang University, Hangzhou 311115, China
| | - Hefeng Zhang
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center of Ministry of Ecology and Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Yanjun Wang
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center of Ministry of Ecology and Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yinger Zheng
- Aviation Safety Institute, China Academy of Civil Aviation Science and Technology (Civil Aviation Safety Engineering Technology Research Center), Beijing 101300, China
| | - Shenghui Zhong
- International Innovation Institute, Beihang University, Hangzhou 311115, China
| | - Kang Pan
- International Innovation Institute, Beihang University, Hangzhou 311115, China
| | - Yiwei Zhao
- International Innovation Institute, Beihang University, Hangzhou 311115, China; School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Mengyun Gao
- International Innovation Institute, Beihang University, Hangzhou 311115, China; School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Bin Zhang
- International Innovation Institute, Beihang University, Hangzhou 311115, China
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2
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Gualtieri M, Berico M, Grollino MG, Cremona G, La Torretta T, Malaguti A, Petralia E, Stracquadanio M, Santoro M, Benassi B, Piersanti A, Chiappa A, Bernabei M, Zanini G. Emission Factors of CO 2 and Airborne Pollutants and Toxicological Potency of Biofuels for Airplane Transport: A Preliminary Assessment. TOXICS 2022; 10:617. [PMID: 36287897 PMCID: PMC9611748 DOI: 10.3390/toxics10100617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Aviation is one of the sectors affecting climate change, and concerns have been raised over the increase in the number of flights all over the world. To reduce the climate impact, efforts have been dedicated to introducing biofuel blends as alternatives to fossil fuels. Here, we report environmentally relevant data on the emission factors of biofuel/fossil fuel blends (from 13 to 17% v/v). Moreover, in vitro direct exposure of human bronchial epithelial cells to the emissions was studied to determine their potential intrinsic hazard and to outline relevant lung doses. The results show that the tested biofuel blends do not reduce the emissions of particles and other chemical species compared to the fossil fuel. The blends do reduce the elemental carbon (less than 40%) and total volatile organic compounds (less than 30%) compared to fossil fuel emissions. The toxicological outcomes show an increase in oxidative cellular response after only 40 min of exposure, with biofuels causing a lower response compared to fossil fuels, and lung-deposited doses show differences among the fuels tested. The data reported provide evidence of the possibility to reduce the climate impact of the aviation sector and contribute to the risk assessment of biofuels for aviation.
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Affiliation(s)
- Maurizio Gualtieri
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Massimo Berico
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | | | - Giuseppe Cremona
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Teresa La Torretta
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Antonella Malaguti
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Ettore Petralia
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Milena Stracquadanio
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Massimo Santoro
- ENEA, Division of Health Protection Technologies, Via Anguillarese, 301, 00123 Rome, Italy
| | - Barbara Benassi
- ENEA, Division of Health Protection Technologies, Via Anguillarese, 301, 00123 Rome, Italy
| | - Antonio Piersanti
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
| | - Andrea Chiappa
- Italian Air Force, Aerospatial Testing Division, Aerospace Materials and Technology Department, Aeroporto Militare de Bernardi 00071 Pratica di Mare, Pomezia, 00040 Rome, Italy
| | - Manuele Bernabei
- Italian Air Force, Aerospatial Testing Division, Aerospace Materials and Technology Department, Aeroporto Militare de Bernardi 00071 Pratica di Mare, Pomezia, 00040 Rome, Italy
| | - Gabriele Zanini
- ENEA, Division of Models and Technologies for Risk Reduction, Via Martiri di Monte Sole 4, 40146 Bologna, Italy
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3
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Zhang H, Lin Y, Wei S, Loo BPY, Lai PC, Lam YF, Wan L, Li Y. Global association between satellite-derived nitrogen dioxide (NO 2) and lockdown policies under the COVID-19 pandemic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:144148. [PMID: 33360135 PMCID: PMC7833254 DOI: 10.1016/j.scitotenv.2020.144148] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/15/2020] [Accepted: 10/23/2020] [Indexed: 05/22/2023]
Abstract
The COVID-19 pandemic has severely affected various aspects of life, at different levels and in different countries on almost every continent. In response, many countries have closed their borders and imposed lockdown policies, possibly bringing benefits to people's health with significantly less emission from air pollutants. Currently, most studies or reports are based on local observations at the city or country level. There remains a lack of systematic understanding of the impacts of different lockdown policies on the air quality from a global perspective. This study investigates the impacts of COVID-19 pandemic towards global air quality through examining global nitrogen dioxide (NO2) dynamics from satellite observations between 1 January and 30 April 2020. We used the Apriori algorithm, an unsupervised machine learning method, to investigate the association among confirmed cases of COVID-19, NO2 column density, and the lockdown policies in 187 countries. The findings based on weekly data revealed that countries with new cases adopted various lockdown policies to stop or prevent the virus from spreading whereas those without tended to adopt a wait-and-see attitude without enforcing lockdown policies. Interestingly, decreasing NO2 concentration due to lockdown was associated with international travel controls but not with public transport closure. Increasing NO2 concentration was associated with the "business as usual" strategy as evident from North America and Europe during the early days of COVID-19 outbreak (late January to early February 2020), as well as in recent days (in late April) after many countries have started to resume economic activities. This study enriches our understanding of the heterogeneous patterns of global associations among the COVID-19 spreading, lockdown policies and their environmental impacts on NO2 dynamics.
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Affiliation(s)
- Hongsheng Zhang
- Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong.
| | - Yinyi Lin
- Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Shan Wei
- Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong.
| | - Becky P Y Loo
- Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong.
| | - P C Lai
- Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong.
| | - Yun Fat Lam
- Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong.
| | - Luoma Wan
- Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Yu Li
- Faculty of Information Technology, Beijing University of Technology, Beijing, China.
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4
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Hudda N, Durant LW, Fruin SA, Durant JL. Impacts of Aviation Emissions on Near-Airport Residential Air Quality. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:8580-8588. [PMID: 32639745 DOI: 10.1021/acs.est.0c01859] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Impacts of aviation emissions on air quality in and around residences near airports remain underexamined. We measured gases (CO, CO2, NO, and NO2) and particles (black carbon, particle-bound aromatic hydrocarbons, fine particulate matter (PM2.5), and ultrafine particles (reported using particle number concentrations (PNC) as a proxy)) continuously for 1 month at a residence near the Logan International Airport, Boston. The residence was located under a flight trajectory of the most utilized runway configuration. We found that when the residence was downwind of the airport, the concentrations of all gaseous and particulate pollutants (except PM2.5) were 1.1- to 4.8-fold higher than when the residence was not downwind of the airport. Controlling for runway usage and meteorology, the impacts were highest during overhead landing operations: average PNC was 7.5-fold higher from overhead landings versus takeoffs on the closest runway. Infiltration of aviation-origin emissions resulted in indoor PNC that were comparable to ambient concentrations measured locally on roadways and near highways. In addition, ambient NO2 concentrations at the residence exceeded those measured at regulatory monitoring sites in the area including near-road monitors. Our results highlight the need for further characterization of outdoor and indoor impacts of aviation emissions at the neighborhood scale to more accurately estimate residential exposures.
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Affiliation(s)
- Neelakshi Hudda
- Department of Civil and Environmental Engineering, Tufts University, 200 College Avenue, Medford, Massachusetts 02155, United States
| | - Liam W Durant
- Department of Electrical and Computer Engineering, Tufts University, 161 College Avenue, Medford, Massachusetts 02155, United States
| | - Scott A Fruin
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, 2001 N. Soto Street, Los Angeles, California 90033, United States
| | - John L Durant
- Department of Civil and Environmental Engineering, Tufts University, 200 College Avenue, Medford, Massachusetts 02155, United States
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5
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Dong Y, Gu M, Zhu G, Tan T, Liu K, Gao X. Fully Integrated Photoacoustic NO 2 Sensor for Sub-ppb Level Measurement. SENSORS 2020; 20:s20051270. [PMID: 32110962 PMCID: PMC7085709 DOI: 10.3390/s20051270] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/21/2020] [Accepted: 02/24/2020] [Indexed: 11/21/2022]
Abstract
A fully integrated photoacoustic nitrogen dioxide (NO2) sensor is developed and demonstrated. In this sensor, an embedded photoacoustic cell was manufactured by using an up-to-date 3D printing technique. A blue laser diode was used as a light source for excitation of photoacoustic wave in the photoacoustic cell. The photoacoustic wave is detected by a sensitive microelectromechanical system (MEMS) microphone. Homemade circuits are integrated into the sensor for laser diode driving and signal processing. The sensor was calibrated by using a chemiluminescence NO–NO2–NOX gas analyzer. And the performance of this sensor was evaluated. The linear relationship between photoacoustic signals and NO2 concentrations was verified in a range of below 202 ppb. The limit of detection was determined to 0.86 ppb with an integration time of 1 s. The corresponding normalized noise equivalent absorption was 2.0 × 10−8 cm−1∙W∙Hz−1/2. The stability and the optimal integration time were evaluated with an Allan deviation analysis, from which a detection limit of 0.25 ppb at the optimal integration time of 240 s was obtained. The sensor was used to measure outdoor air and the results agree with that obtained from the NO–NO2–NOX gas analyzer. The low-cost and portable photoacoustic NO2 sensor has a potential application for atmospheric NO2 monitoring.
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Affiliation(s)
- Yang Dong
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Mingsi Gu
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Gongdong Zhu
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
| | - Tu Tan
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
| | - Kun Liu
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
| | - Xiaoming Gao
- Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China; (Y.D.); (M.G.); (G.Z.); (T.T.); (K.L.)
- Correspondence:
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6
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Manago N, Takara Y, Ando F, Noro N, Suzuki M, Irie H, Kuze H. Visualizing spatial distribution of atmospheric nitrogen dioxide by means of hyperspectral imaging. APPLIED OPTICS 2018; 57:5970-5977. [PMID: 30118021 DOI: 10.1364/ao.57.005970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
We have developed a method to monitor the slant column density of nitrogen dioxide in the lower troposphere using a compact hyperspectral camera with a high spectral resolution of 1 nm at the full width half-maximum. Measurements of skylight spectra were conducted in wavelength regions of 460-490 nm and 550-610 nm to retrieve the slant column densities of nitrogen dioxide, in addition to water vapor and oxygen dimer. The results of ground-based measurements are shown for the cases of urban air pollution and aircraft emission near an airport runway.
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7
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Pecorari E, Mantovani A, Franceschini C, Bassano D, Palmeri L, Rampazzo G. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 541:839-856. [PMID: 26437354 DOI: 10.1016/j.scitotenv.2015.08.147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 08/15/2015] [Accepted: 08/30/2015] [Indexed: 05/20/2023]
Abstract
The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po' Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15-50%) has been observed during specific meteorological events.
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Affiliation(s)
- Eliana Pecorari
- Department of Environmental Science, Informatics and Statistics, University Ca' Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia, Italy.
| | - Alice Mantovani
- OSMOTECH S.r.l., via Francesco Sforza, 15, 20122 Milano, Italy
| | - Chiara Franceschini
- Department of Environmental Science, Informatics and Statistics, University Ca' Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia, Italy
| | - Davide Bassano
- SAVE S.p.A., Marco Polo Venice airport viale G. Galilei 30/1, 30173 Tessera-Venezia, Italy
| | - Luca Palmeri
- Department of Industrial Engineering, University of Padova, v. Marzolo 9, 35131 Padova, Italy
| | - Giancarlo Rampazzo
- Department of Environmental Science, Informatics and Statistics, University Ca' Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia, Italy
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8
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Masiol M, Harrison RM. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2014; 95:409-455. [PMID: 32288558 PMCID: PMC7108289 DOI: 10.1016/j.atmosenv.2014.05.070] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 05/23/2014] [Accepted: 05/26/2014] [Indexed: 05/06/2023]
Abstract
Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.
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Affiliation(s)
- Mauro Masiol
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Roy M Harrison
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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9
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Hudda N, Gould T, Hartin K, Larson T, Fruin SA. Emissions from an international airport increase particle number concentrations 4-fold at 10 km downwind. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:6628-35. [PMID: 24871496 PMCID: PMC4215878 DOI: 10.1021/es5001566] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We measured the spatial pattern of particle number (PN) concentrations downwind from the Los Angeles International Airport (LAX) with an instrumented vehicle that enabled us to cover larger areas than allowed by traditional stationary measurements. LAX emissions adversely impacted air quality much farther than reported in previous airport studies. We measured at least a 2-fold increase in PN concentrations over unimpacted baseline PN concentrations during most hours of the day in an area of about 60 km(2) that extended to 16 km (10 miles) downwind and a 4- to 5-fold increase to 8-10 km (5-6 miles) downwind. Locations of maximum PN concentrations were aligned to eastern, downwind jet trajectories during prevailing westerly winds and to 8 km downwind concentrations exceeded 75 000 particles/cm(3), more than the average freeway PN concentration in Los Angeles. During infrequent northerly winds, the impact area remained large but shifted to south of the airport. The freeway length that would cause an impact equivalent to that measured in this study (i.e., PN concentration increases weighted by the area impacted) was estimated to be 280-790 km. The total freeway length in Los Angeles is 1500 km. These results suggest that airport emissions are a major source of PN in Los Angeles that are of the same general magnitude as the entire urban freeway network. They also indicate that the air quality impact areas of major airports may have been seriously underestimated.
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Affiliation(s)
- Neelakshi Hudda
- Keck
School of Medicine, Department of Preventive Medicine, University of Southern California, Los Angeles, California 90089, United States
| | - Tim Gould
- Department
of Civil and Environmental Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Kris Hartin
- Department
of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington 98195, United States
| | - Timothy
V. Larson
- Department
of Civil and Environmental Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Scott A. Fruin
- Keck
School of Medicine, Department of Preventive Medicine, University of Southern California, Los Angeles, California 90089, United States
- Phone: 323-442-2870; fax: 323-442-3272; e-mail:
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10
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Bossioli E, Tombrou M, Helmis C, Kurtenbach R, Wiesen P, Schäfer K, Dandou A, Varotsos KV. Issues related to aircraft take-off plumes in a mesoscale photochemical model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 456-457:69-81. [PMID: 23584035 DOI: 10.1016/j.scitotenv.2013.02.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 02/07/2013] [Accepted: 02/27/2013] [Indexed: 06/02/2023]
Abstract
The physical and chemical characteristics of aircraft plumes at the take-off phase are simulated with the mesoscale CAMx model using the individual plume segment approach, in a highly resolved domain, covering the Athens International Airport. Emission indices during take-off measured at the Athens International Airport are incorporated. Model predictions are compared with in situ point and path-averaged observations (NO, NO₂) downwind of the runway at the ground. The influence of modeling process, dispersion properties and background air composition on the chemical evolution of the aircraft plumes is examined. It is proven that the mixing properties mainly determine the plume dispersion. The initial plume properties become significant for the selection of the appropriate vertical resolution. Besides these factors, the background NOx and O₃ concentration levels control NOx distribution and their conversion to nitrogen reservoir species.
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Affiliation(s)
- Elissavet Bossioli
- National and Kapodistrian University of Athens, Division of Physics, Department of Environmental Physics and Meteorology, Build. Phys. V, University Campus, Zografou, 157 84 Athens, Greece.
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11
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Timko MT, Fortner E, Franklin J, Yu Z, Wong HW, Onasch TB, Miake-Lye RC, Herndon SC. Atmospheric measurements of the physical evolution of aircraft exhaust plumes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:3513-3520. [PMID: 23356965 DOI: 10.1021/es304349c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Drawing from a series of field measurement activities including the Alternative Aviation Fuels Experiments (AAFEX1 and AAFEX2), we present experimental measurements of particle number, size, and composition-resolved mass that describe the physical and chemical evolution of aircraft exhaust plumes on the time scale of 5 s to 2-3 min. As the plume ages, the particle number emission index initially increases by a factor of 10-50, due to gas-to-particle formation of a nucleation/growth mode, and then begins to fall with increased aging. Increasing the fuel sulfur content causes the initial increase to occur more rapidly. The contribution of the nucleation/growth mode to the overall particle number density is most pronounced at idle power and decreases with increasing engine power. Increasing fuel sulfur content, but not fuel aromatic content causes the nucleation/growth mode to dominate the particle number emissions at higher powers than for a fuel with "normal" sulfur and aromatic content. Particle size measurements indicate that the observed particle number emissions trends are due to continuing gas-to-particle conversion and coagulation growth of the nucleation/growth mode particles, processes which simultaneously increase particle mass and reduce particle number density. Measurements of nucleation/growth mode mass are consistent with the interpretation of particle number and size data and suggest that engine exit plane measurements may underestimate the total particle mass by as much as a factor of between 5 and 10.
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Affiliation(s)
- M T Timko
- Aerodyne Research, Inc, 45 Manning Road, Billerica Massachusetts 01821, United States
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12
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Buonanno G, Bernabei M, Avino P, Stabile L. Occupational exposure to airborne particles and other pollutants in an aviation base. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2012; 170:78-87. [PMID: 22771354 DOI: 10.1016/j.envpol.2012.05.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 05/17/2012] [Accepted: 05/21/2012] [Indexed: 05/20/2023]
Abstract
The occupational exposure to airborne particles and other pollutants in a high performance jet engine airport was investigated. Three spatial scales were considered: i) a downwind receptor site, ii) close to the airstrip, iii) personal monitoring. Particle number, surface area, mass concentrations and distributions were measured as well as inorganic and organic fractions, ionic fractions and Polycyclic Aromatic Hydrocarbons. Particle number distribution measured at a receptor site presents a mode of 80 nm and an average total concentration of 6.5 × 10(3) part. cm(-3); the chemical analysis shows that all the elements may be attributed to long-range transport from the sea. Particle number concentrations in the proximity of the airstrip show short term peaks during the working day mainly related to takeoff, landing and pre-flight operations of jet engines. Personal exposure of workers highlights a median number concentration of 2.5 × 10(4) part. cm(-3) and 1.7 × 10(4) part. cm(-3) for crew chief and hangar operator.
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Affiliation(s)
- Giorgio Buonanno
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, Italy.
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13
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Klapmeyer ME, Marr LC. CO2, NOx, and particle emissions from aircraft and support activities at a regional airport. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:10974-10981. [PMID: 22963581 DOI: 10.1021/es302346x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The goal of this research was to quantify emissions of carbon dioxide (CO(2)), nitrogen oxides (NO(x)), particle number, and black carbon (BC) from in-use aircraft and related activity at a regional airport. Pollutant concentrations were measured adjacent to the airfield and passenger terminal at the Roanoke Regional Airport in Virginia. Observed NO(x) emission indices (EIs) for jet-powered, commuter aircraft were generally lower than those contained in the International Civil Aviation Organization databank for both taxi (same as idle) and takeoff engine settings. NO(x) EIs ranged from 1.9 to 3.7 g (kg fuel)(-1) across five types of aircraft during taxiing, whereas EIs were consistently higher, 8.8-20.6 g (kg fuel)(-1), during takeoff. Particle number EIs ranged from 1.4 × 10(16) to 7.1 × 10(16) (kg fuel)(-1) and were slightly higher in taxi mode than in takeoff mode for four of the five types of aircraft. Diurnal patterns in CO(2) and NO(x) concentrations were influenced mainly by atmospheric conditions, while patterns in particle number concentrations were attributable mainly to patterns in aircraft activity. CO(2) and NO(x) fluxes measured by eddy covariance were higher at the terminal than at the airfield and were lower than found in urban areas.
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Affiliation(s)
- Michael E Klapmeyer
- Department of Civil and Environmental Engineering, Virginia Tech, 418 Durham Hall, Blacksburg, Virginia, 24061, USA
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14
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Herndon SC, Nelson DD, Wood EC, Knighton WB, Kolb CE, Kodesh Z, Torres VM, Allen DT. Application of the Carbon Balance Method to Flare Emissions Characteristics. Ind Eng Chem Res 2012. [DOI: 10.1021/ie202676b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott C. Herndon
- Aerodyne Research, Inc., Billerica, Massachusetts, United States
| | - David D. Nelson
- Aerodyne Research, Inc., Billerica, Massachusetts, United States
| | - Ezra C. Wood
- Aerodyne Research, Inc., Billerica, Massachusetts, United States
- Department of Public Health, University of Massachusetts, Amherst, Massachusetts,
United States
| | - W. Berk Knighton
- Department
of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, United
States
| | - Charles E. Kolb
- Aerodyne Research, Inc., Billerica, Massachusetts, United States
| | - Zach Kodesh
- John Zink Company, LLC, Tulsa, Oklahoma, United States
| | - Vincent M. Torres
- Center for Energy and Environment
Resources, University of Texas, Austin,
Texas, United States
| | - David T. Allen
- Center for Energy and Environment
Resources, University of Texas, Austin,
Texas, United States
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15
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Lee BH, Santoni GW, Wood EC, Herndon SC, Miake-Lye RC, Zahniser MS, Wofsy SC, Munger JW. Measurements of nitrous acid in commercial aircraft exhaust at the Alternative Aviation Fuel Experiment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7648-7654. [PMID: 21809872 DOI: 10.1021/es200921t] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The Alternative Aviation Fuel Experiment (AAFEX), conducted in January of 2009 in Palmdale, California, quantified aerosol and gaseous emissions from a DC-8 aircraft equipped with CFM56-2C1 engines using both traditional and synthetic fuels. This study examines the emissions of nitrous acid (HONO) and nitrogen oxides (NO(x) = NO + NO(2)) measured 145 m behind the grounded aircraft. The fuel-based emission index (EI) for HONO increases approximately 6-fold from idle to takeoff conditions but plateaus between 65 and 100% of maximum rated engine thrust, while the EI for NO(x) increases continuously. At high engine power, NO(x) EI is greater when combusting traditional (JP-8) rather than Fischer-Tropsch fuels, while HONO exhibits the opposite trend. Additionally, hydrogen peroxide (H(2)O(2)) was identified in exhaust plumes emitted only during engine idle. Chemical reactions responsible for emissions and comparison to previous measurement studies are discussed.
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Affiliation(s)
- Ben H Lee
- Harvard University, Cambridge, MA 02138, USA.
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16
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Santoni GW, Lee BH, Wood EC, Herndon SC, Miake-Lye RC, Wofsy SC, McManus JB, Nelson DD, Zahniser MS. Aircraft emissions of methane and nitrous oxide during the alternative aviation fuel experiment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7075-7082. [PMID: 21728352 DOI: 10.1021/es200897h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Given the predicted growth of aviation and the recent developments of alternative aviation fuels, quantifying methane (CH(4)) and nitrous oxide (N(2)O) emission ratios for various aircraft engines and fuels can help constrain projected impacts of aviation on the Earth's radiative balance. Fuel-based emission indices for CH(4) and N(2)O were quantified from CFM56-2C1 engines aboard the NASA DC-8 aircraft during the first Alternative Aviation Fuel Experiment (AAFEX-I) in 2009. The measurements of JP-8 fuel combustion products indicate that at low thrust engine states (idle and taxi, or 4% and 7% maximum rated thrusts, respectively) the engines emit both CH(4) and N(2)O at a mean ± 1σ rate of 170 ± 160 mg CH(4) (kg Fuel)(-1) and 110 ± 50 mg N(2)O (kg Fuel)(-1), respectively. At higher thrust levels corresponding to greater fuel flow and higher engine temperatures, CH(4) concentrations in engine exhaust were lower than ambient concentrations. Average emission indices for JP-8 fuel combusted at engine thrusts between 30% and 100% of maximum rating were -54 ± 33 mg CH(4) (kg Fuel)(-1) and 32 ± 18 mg N(2)O (kg Fuel)(-1), where the negative sign indicates consumption of atmospheric CH(4) in the engine. Emission factors for the synthetic Fischer-Tropsch fuels were statistically indistinguishable from those for JP-8.
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Affiliation(s)
- Gregory W Santoni
- School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St., Cambridge, Massachusetts 02138, USA.
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17
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Whitt DB, Jacobson MZ, Wilkerson JT, Naiman AD, Lele SK. Vertical mixing of commercial aviation emissions from cruise altitude to the surface. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd015532] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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18
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Abstract
An improved approach has been developed for ultra-sensitive detection of the concentration of NO using Faraday Modulation spectrometry (FAMOS) combined with the strong electronic transition. By changing the modulating magnetic field attributing to linear absorption and refraction of gas sample, the polarized laser was rotated and absorbed by the complex refraction index of NO. We confirm the relation between the magnitudes of absorption and the optimum modulation magnetic field. Also, the accuracy and the precision of the technique have been evaluated at different pressures. It is shown that the system is capable of detecting NO concentration down to 0.34 ppb·m.
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Affiliation(s)
- Yixian Qian
- Institute of Information Optics, Zhejiang Normal University, Jinhua, China.
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19
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Herndon SC, Wood EC, Northway MJ, Miake-Lye R, Thornhill L, Beyersdorf A, Anderson BE, Dowlin R, Dodds W, Knighton WB. Aircraft hydrocarbon emissions at Oakland International Airport. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:1730-1736. [PMID: 19368164 DOI: 10.1021/es801307m] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
To help airports improve emission inventory data, speciated hydrocarbon emission indices have been measured from in-use commercial, airfreight, and general aviation aircraft at Oakland International Airport. The compounds reported here include formaldehyde, acetaldehyde, ethene, propene, and benzene. At idle, the magnitude of hydrocarbon emission indices was variable and reflected differences in engine technology, actual throttle setting, and ambient temperature. Scaling the measured emission indices to the simultaneously measured formaldehyde (HCHO) emission index eliminated most of the observed variability. This result supports a uniform hydrocarbon emissions profile across engine types when the engine is operating near idle, which can greatly simplify how speciated hydrocarbons are handled in emission inventories. The magnitude of the measured hydrocarbon emission index observed in these measurements (ambient temperature range 12-22 degrees C) is a factor of 1.5-2.2 times larger than the certification benchmarks. Using estimates of operational fuel flow rates at idle, this analysis suggests that current emission inventories at the temperatures encountered at this airport underestimate hydrocarbon emissions from the idle phase of operation by 16-45%.
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20
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Application of non-linear time-alignment and integration methods to environmental time series. Trends Analyt Chem 2009. [DOI: 10.1016/j.trac.2008.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Johnson GR, Mazaheri M, Ristovski ZD, Morawska L. A plume capture technique for the remote characterization of aircraft engine emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:4850-4856. [PMID: 18678016 DOI: 10.1021/es702581m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A technique for capturing and analyzing plumes from unmodified aircraft or other combustion sources under real world conditions is described and applied to the task of characterizing plumes from commercial aircraft during the taxiing phase of the Landing/Take-Off (LTO) cycle. The method utilizes a Plume Capture and Analysis System (PCAS) mounted in a four-wheel drive vehicle which is positioned in the airfield 60 to 180 m downwind of aircraft operations. The approach offers low test turnaround times with the ability to complete careful measurements of particle and gaseous emission factors and sequentially scanned particle size distributions without distortion due to plume concentration fluctuations. These measurements can be performed for individual aircraft movements at five minute intervals. A Plume Capture Device (PCD) collected samples of the naturally diluted plume in a 200 L conductive membrane conforming to a defined shape. Samples from over 60 aircraft movements were collected and analyzed in situ for particulate and gaseous concentrations and for particle size distribution using a Scanning Particle Mobility Sizer (SMPS). Emission factors are derived for particle number, NO(x), and PM2.5 for a widely used commercial aircraft type, Boeing 737 airframes with predominantly CFM56 class engines, during taxiing. The practical advantages of the PCAS include the capacity to perform well targeted and controlled emission factor and size distribution measurements using instrumentation with varying response times within an airport facility, in close proximity to aircraft during their normal operations.
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Affiliation(s)
- G R Johnson
- International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia
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22
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Carslaw DC, Ropkins K, Laxen D, Moorcroft S, Marner B, Williams ML. Near-field commercial aircraft contribution to nitrogen oxides by engine, aircraft type, and airline by individual plume sampling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:1871-1876. [PMID: 18409606 DOI: 10.1021/es071926a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrogen oxides (NOx) concentrations were measured in individual plumes from aircraft departing on the northern runway at Heathrow Airport in west London. Over a period of four weeks 5618 individual plumes were sampled by a chemiluminescence monitor located 180 m from the runway. Results were processed and matched with detailed aircraft movement and aircraft engine data using chromatographic techniques. Peak concentrations associated with 29 commonly used engines were calculated and found to have a good relationship with N0x emissions taken from the International Civil Aviation Organization (ICAO) databank. However, it is found that engines with higher reported NOx emissions result in proportionately lower NOx concentrations than engines with lower emissions. We show that it is likely that aircraft operational factors such as takeoff weight and aircraftthrust setting have a measurable and important effect on concentrations of N0x. For example, NOx concentrations can differ by up to 41% for aircraft using the same airframe and engine type, while those due to the same engine type in different airframes can differ by 28%. These differences are as great as, if not greater than, the reported differences in NOx emissions between different engine manufacturers for engines used on the same airframe.
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Affiliation(s)
- David C Carslaw
- Institute for Transport Studies, University of Leeds, Leeds, UK.
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23
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Wood EC, Herndon SC, Timko MT, Yelvington PE, Miake-Lye RC. Speciation and chemical evolution of nitrogen oxides in aircraft exhaust near airports. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:1884-1891. [PMID: 18409608 DOI: 10.1021/es072050a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Measurements of nitrogen oxides from a variety of commercial aircraft engines as part of the JETS-APEX2 and APEX3 campaigns show that NOx (NOx [triple bond] NO + NO2) is emitted primarily in the form of NO2 at idle thrust and NO at high thrust. A chemical kinetics combustion model reproduces the observed NO2 and NOx trends with engine power and sheds light on the relevant chemical mechanisms. Experimental evidence is presented of rapid conversion of NO to NO2 in the exhaust plume from engines at low thrust. The rapid conversion and the high NO2/NOx emission ratios observed are unrelated to ozone chemistry. NO2 emissions from a CFM56-3B1 engine account for approximately 25% of the NOx emitted below 3000 feet (916 m) and 50% of NOx emitted below 500 feet (153 m) during a standard ICAO (International Civil Aviation Organization) landing-takeoff cycle. Nitrous acid (HONO) accounts for 0.5% to 7% of NOy emissions from aircraft exhaust depending on thrust and engine type. Implications for photochemistry near airports resulting from aircraft emissions are discussed.
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Affiliation(s)
- Ezra C Wood
- Aerodyne Research, Inc., 45 Manning Road, Billerica, Massachusetts 01821, USA.
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24
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Herndon SC, Jayne JT, Lobo P, Onasch TB, Fleming G, Hagen DE, Whitefield PD, Miake-Lye RC. Commercial aircraft engine emissions characterization of in-use aircraft at Hartsfield-Jackson Atlanta International Airport. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:1877-1883. [PMID: 18409607 DOI: 10.1021/es072029+] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The emissions from in-use commercial aircraft engines have been analyzed for selected gas-phase species and particulate characteristics using continuous extractive sampling 1-2 min downwind from operational taxi- and runways at Hartsfield-Jackson Atlanta International Airport. Using the aircraft tail numbers, 376 plumes were associated with specific engine models. In general, for takeoff plumes, the measured NOx emission index is lower (approximately 18%) than that predicted by engine certification data corrected for ambient conditions. These results are an in-service observation of the practice of "reduced thrust takeoff". The CO emission index observed in ground idle plumes was greater (up to 100%) than predicted by engine certification data for the 7% thrust condition. Significant differences are observed in the emissions of black carbon and particle number among different engine models/technologies. The presence of a mode at approximately 65 nm (mobility diameter) associated with takeoff plumes and a smaller mode at approximately 25 nm associated with idle plumes has been observed. An anticorrelation between particle mass loading and particle number concentration is observed.
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Affiliation(s)
- Scott C Herndon
- Aerodyne Research, Inc. Billerica, Massachusetts 01821, USA.
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25
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Herndon SC, Rogers T, Dunlea EJ, Jayne JT, Miake-Lye R, Knighton B. Hydrocarbon emissions from in-use commercial aircraft during airport operations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:4406-13. [PMID: 16903278 DOI: 10.1021/es051209l] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The emissions of selected hydrocarbons from in-use commercial aircraft at a major airport in the United States were characterized using proton-transfer reaction mass spectrometry (PTR-MS) and tunable infrared differential absorption spectroscopy (TILDAS) to probe the composition of diluted exhaust plumes downwind. The emission indices for formaldehyde, acetaldehyde, benzene, and toluene, as well as other hydrocarbon species, were determined through analysis of 45 intercepted plumes identified as being associated with specific aircraft. As would have been predicted for high bypass turbine engines, the hydrocarbon emission index was greater in idle and taxiway acceleration plumes relative to approach and takeoff plumes. The opposite was seen in total NOy emission index, which increased from idle to takeoff. Within the idle plumes sampled in this study, the median emission index for formaldehyde was 1.1 g of HCHO per kg of fuel. For the subset of hydrocarbons measured in this work, the idle emissions levels relative to formaldehyde agree well with those of previous studies. The projected total unburned hydrocarbons (UHC) deduced from the range of in-use idle plumes analyzed in this work is greater than a plausible range of engine types using the defined idle condition (7% of rated engine thrust) in the International Civil Aviation Organization (ICAO) databank reference.
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26
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Shorter JH, Nelson DD, Zahniser MS, Parrish ME, Crawford DR, Gee DL. Measurement of nitrogen dioxide in cigarette smoke using quantum cascade tunable infrared laser differential absorption spectroscopy (TILDAS). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 63:994-1001. [PMID: 16490384 DOI: 10.1016/j.saa.2005.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2005] [Revised: 11/02/2005] [Accepted: 11/02/2005] [Indexed: 05/06/2023]
Abstract
Although nitrogen dioxide (NO(2)) has been previously reported to be present in cigarette smoke, the concentration estimates were derived from kinetic calculations or from measurements of aged smoke, where NO(2) was formed some time after the puff was taken. The objective of this work was to use tunable infrared laser differential absorption spectroscopy (TILDAS) equipped with a quantum cascade (QC) laser to determine if NO(2) could be detected and quantified in a fresh puff of cigarette smoke. A temporal resolution of approximately 0.16s allowed measurements to be taken directly as the NO(2) was formed during the puff. Sidestream cigarette smoke was sampled to determine if NO(2) could be detected using TILDAS. Experiments were conducted using 2R4F Kentucky Reference cigarettes with and without a Cambridge filter pad. NO(2) was detected only in the lighting puff of whole mainstream smoke (without a Cambridge filter pad), with no NO(2) detected in the subsequent puffs. The measurement precision was approximately 1.0 ppbVHz(-1/2), which allows a detection limit of approximately 0.2 ng in a 35 ml puff volume. More NO(2) was generated in the lighting puff using a match or blue flame lighter (29+/-21 ng) than when using an electric lighter (9+/-3 ng). In the presence of a Cambridge filter pad, NO(2) was observed in the gas phase mainstream smoke for every puff (total of 200+/-30 ng/cigarette) and is most likely due to smoke chemistry taking place on the Cambridge filter pad during the smoke collection process. Nitrogen dioxide was observed continuously in the sidestream smoke starting with the lighting puff.
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Affiliation(s)
- Joanne H Shorter
- Aerodyne Research Inc., 45 Manning Road, Billerica, MA 01821-3976 USA.
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27
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Shorter JH, Herndon S, Zahniser MS, Nelson DD, Wormhoudt J, Demerjian KL, Kolb CE. Real-time measurements of nitrogen oxide emissions from in-use New York City transit buses using a chase vehicle. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2005; 39:7991-8000. [PMID: 16295866 DOI: 10.1021/es048295u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
New diesel engine technologies and alternative fuel engines are being introduced into fleets of mass transit buses to try to meet stricter emission regulations of nitrogen oxides and particulates: Real-time instruments including an Aerodyne Research tunable infrared laser differential absorption spectrometer (TILDAS) were deployed in a mobile laboratory to assess the impact of the implementation of the new technologies on nitrogen oxide emissions in real world driving conditions. Using a "chase" vehicle sampling strategy, the mobile laboratory followed target vehicles, repeatedly sampling their exhaust. Nitrogen oxides from approximately 170 in-use New York City mass transit buses were sampled during the field campaigns. Emissions from conventional diesel buses, diesel buses with continuously regenerating technology (CRT), diesel hybrid electric buses, and compressed natural gas (CNG) buses were compared. The chase vehicle sampling method yields real world emissions that can be included in more realistic emission inventories. The NO, emissions from the diesel and CNG buses were comparable. The hybrid electric buses had approximately one-half the NOx emissions. In CRT diesels, NO2 accounts for about one-third of the NOx emitted in the exhaust, while for non-CRT buses the NO2 fraction is less than 10%.
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Affiliation(s)
- Joanne H Shorter
- Center for Atmospheric and Environmental Chemistry, Aerodyne Research, Inc., 45 Manning Road, Billerica, Massachusetts 01821, USA.
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28
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Herndon SC, Shorter JH, Zahniser MS, Wormhoudt J, Nelson DD, Demerjian KL, Kolb CE. Real-time measurements of SO2, H2CO, and CH4 emissions from in-use curbside passenger buses in New York City using a chase vehicle. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2005; 39:7984-90. [PMID: 16295865 DOI: 10.1021/es0482942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The Aerodyne Mobile Laboratory "chased" in-use curbside passenger buses operated by various operators in New York City. With the cooperation of New York State's Metropolitan Transit Authority, the relationships between the emissions of the several gas-phase species and particulate loadings were investigated across several bus technologies, bus types, and fuels (diesel, ultralow sulfur diesel, and compressed natural gas, CNG). The CNG buses followed did not employ an oxidation catalyst. The buses characterized were not prescreened in any fashion and were measured while deployed on their normal in-service routes. This paper focuses on the fuel-based mass emissions of SO2, H2CO, and CH4, measured using tunable infrared laser differential absorption spectroscopy. Sulfur dioxide emissions from buses known to be burning ultralow sulfur diesel (<30 ppm(m) S) were 16 times lower than those from buses burning normal commercial diesel fuel, nominally less than 300 ppm(m) sulfur. Emissions of formaldehyde and methane from in-use CNG buses were approximately 15 times greater than those from diesel powered buses.
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Affiliation(s)
- Scott C Herndon
- Center for Atmospheric and Environmental Chemistry, Aerodyne Research, Inc., Billerica, Massachusetts 01821, USA.
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29
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Herndon SC, Jayne JT, Zahniser MS, Worsnop DR, Knighton B, Alwine E, Lamb BK, Zavala M, Nelson DD, McManus JB, Shorter JH, Canagaratna MR, Onasch TB, Kolb CE. Characterization of urban pollutant emission fluxes and ambient concentration distributions using a mobile laboratory with rapid response instrumentation. Faraday Discuss 2005; 130:327-39; discussion 363-86, 519-24. [PMID: 16161792 DOI: 10.1039/b500411j] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A large and increasing fraction of the planet's population lives in megacities, especially in the developing world. These large metropolitan areas generally have very high levels of both gaseous and particulate air pollutants that have severe impacts on human health, ecosystem viability, and climate on local, regional, and even continental scales. Emissions fluxes and ambient pollutant concentration distributions are generally poorly characterized for large urban areas even in developed nations. Much less is known about pollutant sources and concentration patterns in the faster growing megacities of the developing world. New methods of locating and measuring pollutant emission sources and tracking subsequent atmospheric chemical transformations and distributions are required. Measurement modes utilizing an innovative van based mobile laboratory equipped with a suite of fast response instruments to characterize the complex and "nastier" chemistry of the urban boundary layer are described. Instrumentation and measurement strategies are illustrated with examples from the Mexico City and Boston metropolitan areas. It is shown that fleet average exhaust emission ratios of formaldehyde (HCHO), acetaldehyde (CH3CHO) and benzene (C6H6) are substantial in Mexico City, with gasoline powered vehicles emitting higher levels normalized by fuel consumption. NH3 exhaust emissions from newer light duty vehicles in Mexico City exceed levels from similar traffic in Boston. A mobile conditional sampling air sample collection mode designed to collect samples from intercepted emission plumes for later analysis is also described.
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Affiliation(s)
- Scott C Herndon
- Center for Atmospheric and Environmental Chemistry, Aerodyne Research, Inc., 45 Manning Road, Billerica MA 01821-3976, USA
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