The Experts below are selected from a list of 13809 Experts worldwide ranked by ideXlab platform
Sanjiva K Lele - One of the best experts on this subject based on the ideXlab platform.
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vertical mixing of Commercial Aviation emissions from cruise altitude to the surface
Journal of Geophysical Research, 2011Co-Authors: Daniel B Whitt, A D Naiman, Mark Z Jacobson, J T Wilkerson, Sanjiva K LeleAbstract:[1] Data analysis and numerical simulations were used to examine vertical transport of cruise-altitude Commercial aircraft emissions to the surface. First, aircraft emission data were compared with static stability and potential temperature data from satellites. Second, we ran global 3-D simulations of a passive tracer released uniformly at 11 km (cruise altitude). We present global, regional, and seasonal results of the data comparisons as well as approximate time scales of vertical mixing derived from the simulations. Using the year 2006 as a case study, we found that 24% of all global Commercial Aviation emissions occurred in the stratosphere, 17% occurred both north of 40° N and above the 330 K isentrope, and 54% occurred in regions of at least moderate static stability (N2 > 10−4 s−2). In addition, 74% of emissions in the Arctic Circle were in the stratosphere. In the 3-D simulations, the globally averaged tracer-plume e-folding lifetime against vertical transport to any other altitude was 16 days during January and 14 days during July. Furthermore, the passive tracer took 15 days longer in January (77 days) compared with July (62 days) to achieve a surface-to-cruise mixing ratio fraction greater than 0.5 at all latitudes. The dynamical mixing time scales of extratropical cruise-altitude emissions were significantly longer than the globally averaged wet removal time of 4–5 days for aerosol particles emitted in the lower troposphere. Thus, it is unlikely that cruise-altitude emissions affect surface air quality via transport alone outside the tropics.
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analysis of emission data from global Commercial Aviation 2004 and 2006
Atmospheric Chemistry and Physics, 2010Co-Authors: J T Wilkerson, Mark Z Jacobson, Andrew Malwitz, Sathya Balasubramanian, Roger L Wayson, Gregg G Fleming, A D Naiman, Sanjiva K LeleAbstract:Abstract. The global Commercial aircraft fleet in 2006 flew 31.26 million flights, burned 188.20 million metric tons of fuel, and covered 38.68 billion kilometers. This activity emitted substantial amounts of fossil-fuel combustion products within the upper troposphere and lower stratosphere that affect atmospheric composition and climate. The emissions products, such as carbon monoxide, carbon dioxide, oxides of nitrogen, sulfur compounds, and particulate matter, are not emitted uniformly over the Earth, so understanding the temporal and spatial distributions is important for modeling Aviation's climate impacts. Global Commercial aircraft emission data for 2004 and 2006, provided by the Volpe National Transportation Systems Center, were computed using the Federal Aviation Administration's Aviation Environmental Design Tool (AEDT). Continuous improvement in methodologies, including changes in AEDT's horizontal track methodologies, and an increase in availability of data make some differences between the 2004 and 2006 inventories incomparable. Furthermore, the 2004 inventory contained a significant over-count due to an imperfect data merge and daylight savings error. As a result, the 2006 emissions inventory is considered more representative of actual flight activity. Here, we analyze both 2004 and 2006 emissions, focusing on the latter, and provide corrected totals for 2004. Analysis of 2006 flight data shows that 92.5% of fuel was burned in the Northern Hemisphere, 69.0% between 30N and 60N latitudes, and 74.6% was burned above 7 km. This activity led to 162.25 Tg of carbon from CO2 emitted globally in 2006, more than half over three regions: the United States (25.5%), Europe (14.6), and East Asia (11.1). Despite receiving less than one percent of global emissions, the Arctic receives a uniformly dispersed concentration of emissions with 95.2% released at altitude where they have longer residence time than surface emissions. Finally, 85.2% of all flights by number in 2006 were short-haul missions, yet those flights were responsible for only 39.7% of total carbon from CO2. The following is a summary of these data which illustrates the global and regional Aviation emissions footprints for 2004 and 2006, and provides temporal and spatial distribution statistics.
Dudley E Shallcross - One of the best experts on this subject based on the ideXlab platform.
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a mitigation strategy for Commercial Aviation impact on nox related o3 change
Journal of Geophysical Research, 2016Co-Authors: Donata K Wasiuk, Dudley E Shallcross, Mubarak A Khan, R G Derwent, Mark H LowenbergAbstract:An operational mitigation strategy for Commercial aircraft impact on atmospheric composition, referred to as the turboprop replacement strategy (TRS), is described in this paper. The global air traffic between 2005 and 2011 was modeled with the TRS in which turbofan powered aircraft were replaced with nine chosen turboprop powered aircraft on all routes up to 1700 nautical miles (NM) in range. The results of this TRS double the global number of departures, as well as global mission distance, while global mission time grows by nearly a factor of 3. However, the global mission fuel and the emissions of Aviation CO2, H2O, and SOx remain approximately unchanged, and the total global Aviation CO, hydrocarbons (HC), and NOx emissions are reduced by 79%, 21%, and 11% on average between 2005 and 2011. The TRS lowers the global mean cruise altitude of flights up to 1700 NM by ~2.7 km which leads to a significant decrease in global mission fuel burn, mission time, distance flown, and the aircraft emissions of CO2, CO, H2O, NOx, SOx, and HC above 9.2 km. The replacement of turbofans with turboprops in regional fleets on a global scale leads to an overall reduction in levels of tropospheric O3 at the current estimated mean cruise altitude near the tropopause where the radiative forcing of O3 is strongest. Further, the replacement strategy results in a reduction of ground-level Aviation CO and NOx emissions by 33 and 29%, respectively, between 2005 and 2011.
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an aircraft performance model implementation for the estimation of global and regional Commercial Aviation fuel burn and emissions
Transportation Research Part D-transport and Environment, 2015Co-Authors: Donata K Wasiuk, Mark H Lowenberg, Dudley E ShallcrossAbstract:Estimates of global Aviation fuel burn and emissions are currently nearly 10 years out of date. Here, the development of the Aircraft Performance Model Implementation (APMI) software which is used to update global Commercial Aviation fuel burn and emissions estimates is described. The results from APMI are compared with published estimates obtained using the US Federal Aviation Administration’s System for Assessing Aviation’s Global Emissions (SAGE) for the year 2006. The number of global departures modelled with the APMI software is 8% lower compared with SAGE and reflects the difference between their Commercial air traffic statistics data sources. The mission fuel burn, CO2 and H2O estimates from APMI are approximately 20% lower than those predicted by SAGE for 2006 while the estimate for the total global aircraft SOx emissions is approximately 40% lower. The estimates for the emissions of CO, HC and NOx are 10%, 140% and 30% higher than those predicted by SAGE respectively. The reasons for these differences are discussed in detail.
Donata K Wasiuk - One of the best experts on this subject based on the ideXlab platform.
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a mitigation strategy for Commercial Aviation impact on nox related o3 change
Journal of Geophysical Research, 2016Co-Authors: Donata K Wasiuk, Dudley E Shallcross, Mubarak A Khan, R G Derwent, Mark H LowenbergAbstract:An operational mitigation strategy for Commercial aircraft impact on atmospheric composition, referred to as the turboprop replacement strategy (TRS), is described in this paper. The global air traffic between 2005 and 2011 was modeled with the TRS in which turbofan powered aircraft were replaced with nine chosen turboprop powered aircraft on all routes up to 1700 nautical miles (NM) in range. The results of this TRS double the global number of departures, as well as global mission distance, while global mission time grows by nearly a factor of 3. However, the global mission fuel and the emissions of Aviation CO2, H2O, and SOx remain approximately unchanged, and the total global Aviation CO, hydrocarbons (HC), and NOx emissions are reduced by 79%, 21%, and 11% on average between 2005 and 2011. The TRS lowers the global mean cruise altitude of flights up to 1700 NM by ~2.7 km which leads to a significant decrease in global mission fuel burn, mission time, distance flown, and the aircraft emissions of CO2, CO, H2O, NOx, SOx, and HC above 9.2 km. The replacement of turbofans with turboprops in regional fleets on a global scale leads to an overall reduction in levels of tropospheric O3 at the current estimated mean cruise altitude near the tropopause where the radiative forcing of O3 is strongest. Further, the replacement strategy results in a reduction of ground-level Aviation CO and NOx emissions by 33 and 29%, respectively, between 2005 and 2011.
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an aircraft performance model implementation for the estimation of global and regional Commercial Aviation fuel burn and emissions
Transportation Research Part D-transport and Environment, 2015Co-Authors: Donata K Wasiuk, Mark H Lowenberg, Dudley E ShallcrossAbstract:Estimates of global Aviation fuel burn and emissions are currently nearly 10 years out of date. Here, the development of the Aircraft Performance Model Implementation (APMI) software which is used to update global Commercial Aviation fuel burn and emissions estimates is described. The results from APMI are compared with published estimates obtained using the US Federal Aviation Administration’s System for Assessing Aviation’s Global Emissions (SAGE) for the year 2006. The number of global departures modelled with the APMI software is 8% lower compared with SAGE and reflects the difference between their Commercial air traffic statistics data sources. The mission fuel burn, CO2 and H2O estimates from APMI are approximately 20% lower than those predicted by SAGE for 2006 while the estimate for the total global aircraft SOx emissions is approximately 40% lower. The estimates for the emissions of CO, HC and NOx are 10%, 140% and 30% higher than those predicted by SAGE respectively. The reasons for these differences are discussed in detail.
Mark H Lowenberg - One of the best experts on this subject based on the ideXlab platform.
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a mitigation strategy for Commercial Aviation impact on nox related o3 change
Journal of Geophysical Research, 2016Co-Authors: Donata K Wasiuk, Dudley E Shallcross, Mubarak A Khan, R G Derwent, Mark H LowenbergAbstract:An operational mitigation strategy for Commercial aircraft impact on atmospheric composition, referred to as the turboprop replacement strategy (TRS), is described in this paper. The global air traffic between 2005 and 2011 was modeled with the TRS in which turbofan powered aircraft were replaced with nine chosen turboprop powered aircraft on all routes up to 1700 nautical miles (NM) in range. The results of this TRS double the global number of departures, as well as global mission distance, while global mission time grows by nearly a factor of 3. However, the global mission fuel and the emissions of Aviation CO2, H2O, and SOx remain approximately unchanged, and the total global Aviation CO, hydrocarbons (HC), and NOx emissions are reduced by 79%, 21%, and 11% on average between 2005 and 2011. The TRS lowers the global mean cruise altitude of flights up to 1700 NM by ~2.7 km which leads to a significant decrease in global mission fuel burn, mission time, distance flown, and the aircraft emissions of CO2, CO, H2O, NOx, SOx, and HC above 9.2 km. The replacement of turbofans with turboprops in regional fleets on a global scale leads to an overall reduction in levels of tropospheric O3 at the current estimated mean cruise altitude near the tropopause where the radiative forcing of O3 is strongest. Further, the replacement strategy results in a reduction of ground-level Aviation CO and NOx emissions by 33 and 29%, respectively, between 2005 and 2011.
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an aircraft performance model implementation for the estimation of global and regional Commercial Aviation fuel burn and emissions
Transportation Research Part D-transport and Environment, 2015Co-Authors: Donata K Wasiuk, Mark H Lowenberg, Dudley E ShallcrossAbstract:Estimates of global Aviation fuel burn and emissions are currently nearly 10 years out of date. Here, the development of the Aircraft Performance Model Implementation (APMI) software which is used to update global Commercial Aviation fuel burn and emissions estimates is described. The results from APMI are compared with published estimates obtained using the US Federal Aviation Administration’s System for Assessing Aviation’s Global Emissions (SAGE) for the year 2006. The number of global departures modelled with the APMI software is 8% lower compared with SAGE and reflects the difference between their Commercial air traffic statistics data sources. The mission fuel burn, CO2 and H2O estimates from APMI are approximately 20% lower than those predicted by SAGE for 2006 while the estimate for the total global aircraft SOx emissions is approximately 40% lower. The estimates for the emissions of CO, HC and NOx are 10%, 140% and 30% higher than those predicted by SAGE respectively. The reasons for these differences are discussed in detail.
Konstantinos Boulouchos - One of the best experts on this subject based on the ideXlab platform.
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fuel estimation in air transportation modeling global fuel consumption for Commercial Aviation
Transportation Research Part D-transport and Environment, 2020Co-Authors: K Seymour, Maximilian Held, Gil Georges, Konstantinos BoulouchosAbstract:Abstract Accurate fuel burn estimation models are required to assess potential reductions in CO2 emissions stemming from new aircraft technologies. This study provides a novel framework for Fuel Estimation in Air Transportation (FEAT): a two-component approach comprising of (1) a high fidelity flight profile simulator based on the aircraft performance model from EUROCONTROL, and (2) a reduced order fuel consumption approximation with origin-destination airport pair and aircraft type as sole inputs. The latter allows for accurately estimating fuel consumption for global scheduled aircraft movements of an entire year in a matter of milliseconds. We calculate total CO2 emissions from scheduled Commercial Aviation in 2018 to be 812 Mt. The modeling error of fuel consumption is validated against fuel burn reports and ranges below 5%. Current aircraft performance models either focus on fuel estimation accuracy or on computational efficiency. Combining both, FEAT enables rapid assessment of decarbonization strategies for Commercial passenger Aviation.