“Application and evaluation of the two-way coupled WRF-CMAQ modeling system to the 2011 DISCOVER-AQ campaign in the Baltimore-Washington D.C. area.”

EPA Science Inventory

The DISCOVER-AQ project (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality), is a joint collaboration between NASA, U.S. EPA and a number of other local organizations with the goal of characterizing air quality in ...

TOLNet ozone lidar intercomparison during the discover-aq and frappé campaigns

NASA Astrophysics Data System (ADS)

Newchurch, Michael J.; Alvarez, Raul J.; Berkoff, Timothy A.; Carrion, William; DeYoung, Russell J.; Ganoe, Rene; Gronoff, Guillaume; Kirgis, Guillaume; Kuang, Shi; Langford, Andy O.; Leblanc, Thierry; McGee, Thomas J.; Pliutau, Denis; Senff, Christoph; Sullivan, John T.; Sumnicht, Grant; Twigg, Laurence W.; Wang, Lihua

2018-04-01

The Tropospheric Ozone Lidar Network (TOLNet) is a unique network of lidar systems that measure atmospheric profiles of ozone and aerosols, to contribute to air-quality studies, atmospheric modeling, and satellite validation efforts. The accurate characterization of these lidars is of critical interest, and is necessary to determine cross-instrument calibration uniformity. From July to August 2014, three lidars, the TROPospheric OZone (TROPOZ) lidar, the Tunable Optical Profiler for Aerosol and oZone (TOPAZ) lidar, and the Langley Mobile Ozone Lidar (LMOL), of TOLNet participated in the "Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) mission and the "Front Range Air Pollution and Photochemistry Éxperiment" (FRAPPÉ) to measure sub-hourly ozone variations from near the surface to the top of the troposphere. Although large differences occur at few individual altitudes in the near field and far field range, the TOLNet lidars agree with each other within ±4%. These results indicate excellent measurement accuracy for the TOLNet lidars that is suitable for use in air-quality and ozone modeling efforts.

A Transport Analysis of In Situ Airborne Ozone Measurements from the 2011 DISCOVER-AQ Campaign

NASA Astrophysics Data System (ADS)

Arkinson, H. L.; Brent, L. C.; He, H.; Loughner, C.; Stehr, J. W.; Weinheimer, A. J.; Dickerson, R. R.

2013-12-01

Baltimore and Washington are currently designated as nonattainment areas with respect to the 2008 EPA National Ambient Air Quality Standard (NAAQS) for 8-hour Ozone (O3). Tropospheric O3 is the dominant component of summertime photochemical smog, and at high levels, has deleterious effects on human health, ecosystems, and materials. The University of Maryland (UMD) Regional Atmospheric Measurement Modeling and Prediction Program (RAMMPP) strives to improve understanding of air quality in the Mid-Atlantic States and to elucidate contributions of pollutants such as O3 from regional transport versus local sources through a combination of modeling and in situ measurements. The NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) project investigates the connection between column measurements and surface conditions to explore the potential of remote sensing observations in diagnosing air quality at ground level where pollutants can affect human health. During the 2011 DISCOVER-AQ field campaign, in situ airborne measurements of trace gases and aerosols were performed along the Interstate 95 corridor between Baltimore and Washington from the NASA P3B aircraft. To augment this data and provide regional context, measurements of trace gases and aerosols were also performed by the RAMMPP Cessna 402B aircraft over nearby airports in Maryland and Virginia. This work presents an analysis of O3 measurements made by the Ultraviolet (UV) Photometric Ambient O3 Analyzer on the RAMMPP Cessna 402B and by the NCAR 4-Channel Chemiluminescence instrument on the NASA P3B. In this analysis, spatial and temporal patterns of O3 data are examined within the context of forward and backward trajectories calculated from 12-km North American Mesoscale (NAM) meteorological data using the NOAA Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) Model and from a high resolution Weather Research and

Determining Boundary Layer Mixing State based on NASA DISCOVER-AQ Airborne Soundings over the Baltimore/Washington Area

NASA Astrophysics Data System (ADS)

Chen, G.; Crawford, J. H.; Silverman, M. L.; Anderson, B. E.; Barrick, J. D.; Diskin, G. S.; Fried, A.; Yang, M. M.; Weinheimer, A. J.; Lenschow, D. H.

2012-12-01

The DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) mission conducted its first field deployment in the Washington D.C./Baltimore region during July 2011. The overarching goal is to better understand how remotely-sensed column measurements can be used to diagnose near-surface air quality. To achieve this objective, the DISCOVER-AQ sampling strategy requires extensive probing of the vertical structure of the lower troposphere as it relates to both trace gases and aerosols. This strategy was implemented by using the NASA P-3B aircraft to spiral from 0.3 to ~3 km over 6 MDE (Maryland Department of the Environment) ground monitoring sites. A total of 254 spirals were flown which generated detailed vertical distributions for a large variety of trace gases, aerosol properties, and meteorological variables. This data set allows a detailed assessment of vertical mixing state, which can be estimated by the changes of the measured variables with height within the boundary layer. The data set was further filtered to minimize the influence of the horizontal inhomogeneity. To be presented are cases under different atmospheric stability classes to show the actual observed atmospheric structure and vertical distributions of the aerosols and trace gases which have a wide range of lifetimes.

Trace gas retrievals from Airborne Compact Atmospheric Mapper (ACAM) observations during the 2011 DISCOVER-AQ flight campaign

NASA Astrophysics Data System (ADS)

Liu, X.; Kowalewski, M. G.; Janz, S. J.; Bhartia, P. K.; Chance, K.; Krotkov, N. A.; Pickering, K. E.; Crawford, J. H.

2011-12-01

The DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) mission has just finished its first flight campaign in the Baltimore-Washington D.C. area in July 2011. The ACAM, flown on board the NASA UC-12 aircraft, includes two spectrographs covering the spectral region 304-900 nm and a high-definition video camera, and is expected to provide column measurements of several important air quality trace gases and aerosols for the DISCOVER-AQ mission. The quick look results for NO2 have been shown to very useful in capturing the strong spatiotemporal variability of NO2. Preliminary fitting of UV/Visible spectra has shown that ACAM measurements have adequate signal to noise ratio to measure the trace gases O2, NO2, HCHO, and maybe SO2 and CHOCHO, at individual pixel resolution, although a great deal of effort is needed to improve the instrument calibration and derive proper reference spectrum for retrieving absolute trace gas column densities. In this study, we present analysis of ACAM instrument calibration including slit function, wavelength registration, and radiometric calibration for both nadir-viewing and zenith-sky measurements. Based on this analysis, an irradiance reference spectrum at ACAM resolution will be derived from a high-resolution reference spectrum with additional correction to account for instrument calibration. Using the derived reference spectrum and/or the measured zenith sky measurements, we will perform non-linear least squares fitting to investigate the retrievals of slant column densities of these trace gases from ACAM measurements, and also use an optimal estimation based algorithm including full radiative transfer calculations to derive the vertical column densities of these trace gases. The initial results will be compared with available in-situ and ground-based measurements taken during the DISCOVER-AQ campaign.

Evaluating ammonia (NH3) predictions in the NOAA National Air Quality Forecast Capability (NAQFC) using in situ aircraft, ground-level, and satellite measurements from the DISCOVER-AQ Colorado campaign

NASA Astrophysics Data System (ADS)

Battye, William H.; Bray, Casey D.; Aneja, Viney P.; Tong, Daniel; Lee, Pius; Tang, Youhua

2016-09-01

The U.S. National Oceanic and Atmospheric Administration (NOAA) is responsible for forecasting elevated levels of air pollution within the National Air Quality Forecast Capability (NAQFC). The current research uses measurements gathered in the DISCOVER-AQ Colorado field campaign and the concurrent Front Range Air Pollution and Photochemistry Experiment (FRAPPE) to test performance of the NAQFC CMAQ modeling framework for predicting NH3. The DISCOVER-AQ and FRAPPE field campaigns were carried out in July and August 2014 in Northeast Colorado. Model predictions are compared with measurements of NH3 gas concentrations and the NH4+ component of fine particulate matter concentrations measured directly by the aircraft in flight. We also compare CMAQ predictions with NH3 measurements from ground-based monitors within the DISCOVER-AQ Colorado geographic domain, and from the Tropospheric Emission Spectrometer (TES) on the Aura satellite. In situ aircraft measurements carried out in July and August of 2014 suggest that the NAQFC CMAQ model underestimated the NH3 concentration in Northeastern Colorado by a factor of ∼2.7 (NMB = -63%). Ground-level monitors also produced a similar result. Average satellite-retrieved NH3 levels also exceeded model predictions by a factor of 1.5-4.2 (NMB = -33 to -76%). The underestimation of NH3 was not accompanied by an underestimation of particulate NH4+, which is further controlled by factors including acid availability, removal rate, and gas-particle partition. The average measured concentration of NH4+ was close to the average predication (NMB = +18%). Seasonal patterns measured at an AMoN site in the region suggest that the underestimation of NH3 is not due to the seasonal allocation of emissions, but to the overall annual emissions estimate. The underestimation of NH3 varied across the study domain, with the largest differences occurring in a region of intensive agriculture near Greeley, Colorado, and in the vicinity of Denver. The

Comparison of CMAQ Modeling Study with Discover-AQ 2014 Aircraft Measurements over Colorado

NASA Astrophysics Data System (ADS)

Tang, Y.; Pan, L.; Lee, P.; Tong, D.; Kim, H. C.; Artz, R. S.

2014-12-01

NASA and NCAR jointly led a recent multiple platform-based (space, air and ground) measurement intensive to study air quality and to validate satellite data. The Discover-AQ/FRAPPE field experiment took place along the Colorado Front Range in July and August, 2014. The air quality modeling team of the NOAA Air Resources Laboratory was one of the three teams that provided real-time air quality forecasting for the campaign. The U.S. EPA Community Multi-scale Air Quality (CMAQ) Model was used with emission inventories based on the data set used by the NOAA National Air Quality Forecasting Capacity (NAQFC). By analyzing the forecast results calculated using aircraft measurements, it was found that CO emissions tended to be overestimated, while ethane emissions were underestimated. Biogenic VOCs were also underpredicted. Due to their relatively high altitude, ozone concentrations in Denver and the surrounding areas are affected by both local emissions and transported ozone. The modeled ozone was highly dependent on the meteorological predictions over this region. The complex terrain over the Rocky Mountains also contributed to the model uncertainty. This study discussed the causes of model biases, the forecast performance under different meteorology, and results from using different model grid resolutions. Several data assimilation techniques were further tested to improve the "post-analysis" performance of the modeling system for the period.

DISCOVER-AQ Acoustics : Measurement and Data Report.

DOT National Transportation Integrated Search

2015-09-01

The following report documents the acoustic measurements that supplemented the September 2013 NASA DISCOVER-AQ flight tests in Houston, Texas and the corresponding data set developed from those measurements. These data include aircraft performance an...

The Essential Role of Tethered Balloons in Characterizing Boundary Layer Structure and Evolution during Discover-AQ

NASA Astrophysics Data System (ADS)

Clark, R. D.

2014-12-01

The NASA DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) provided the opportunity to observe the influence of local and regional circulations on the structure and evolution of the boundary layer (BL) and in turn study the associated effects on air quality and aerosol trends within four different airsheds. An extended network of ground-based instruments, balloon-borne profilers, and remote sensing instruments supported the in-situ airborne measurements made by the NASA aircraft in capturing the structure and evolution of the daytime BL. The Millersville University Atmospheric Research and Aerostat Facility (MARAF) is one of many assets deployed for DISCOVER-AQ. Central to MARAF is a heavy-lift-capacity tethered balloon (aerostat) used to obtain high resolution profiles of meteorological variables, trace gases, and particulates in the BL. The benefit of including a tethered balloon is that it can fill a data void between the surface and the lowest altitudes flown by the aircraft and provide critical time-height series for ground-based remote sensing instruments in the layer below their first range gate. MARAF also includes an acoustic sodar with RASS, MPL4 micropulse Lidar, 4-meter flux tower, rawinsonde system, and a suite of trace gas analyzers (O3, NOx/NO2/NO, CO, and SO2), 3-wavelength nephelometer, and particle sizers/counters spanning the range from 10 nm to 10 microns. MARAF is capable of providing a detailed and nearly continuous Eulerian characterization of the surface layer and lower BL, and with proper FAA airspace authorization, can be deployed both day and night. Three case studies will be presented that incorporate the MARAF into the combined assets of DISCOVER-AQ to better characterize: 1) bay breeze convergence, recirculation, and ramp-up events in Edgewood, MD in July 2011; 2) aerosol transport over Central Valley, CA in January 2013; and 3) multiple sea-bay breeze

Improvement of Meteorological Inputs for TexAQS-II Air Quality Simulations

NASA Astrophysics Data System (ADS)

Ngan, F.; Byun, D.; Kim, H.; Cheng, F.; Kim, S.; Lee, D.

2008-12-01

An air quality forecasting system (UH-AQF) for Eastern Texas, which is in operation by the Institute for Multidimensional Air Quality Studies (IMAQS) at the University of Houston, uses the Fifth-Generation PSU/NCAR Mesoscale Model MM5 model as the meteorological driver for modeling air quality with the Community Multiscale Air Quality (CMAQ) model. While the forecasting system was successfully used for the planning and implementation of various measurement activities, evaluations of the forecasting results revealed a few systematic problems in the numerical simulations. From comparison with observations, we observe some times over-prediction of northerly winds caused by inaccurate synoptic inputs and other times too strong southerly winds caused by local sea breeze development. Discrepancies in maximum and minimum temperature are also seen for certain days. Precipitation events, as well as clouds, are simulated at the incorrect locations and times occasionally. Model simulatednrealistic thunderstorms are simulated, causing sometimes cause unrealistically strong outflows. To understand physical and chemical processes influencing air quality measures, a proper description of real world meteorological conditions is essential. The objective of this study is to generate better meteorological inputs than the AQF results to support the chemistry modeling. We utilized existing objective analysis and nudging tools in the MM5 system to develop the MUltiscale Nest-down Data Assimilation System (MUNDAS), which incorporates extensive meteorological observations available in the simulated domain for the retrospective simulation of the TexAQS-II period. With the re-simulated meteorological input, we are able to better predict ozone events during TexAQS-II period. In addition, base datasets in MM5 such as land use/land cover, vegetation fraction, soil type and sea surface temperature are updated by satellite data to represent the surface features more accurately. They are key

Stories from OpenAQ, a Global and Grassroots Open Air Quality Community

NASA Astrophysics Data System (ADS)

Hasenkopf, C. A.; Flasher, J. C.; Veerman, O.; Scalamogna, A.; Silva, D.; Salmon, M.; Buuralda, D.; DeWitt, L. H.

2016-12-01

Air pollution, responsible for more deaths each year than HIV/AIDS and malaria, combined, is a global public health crisis. Yet many scientific questions, including those directly relevant for policy, remain unanswered when it comes to the impact of air pollution on health in highly polluted environments. Often, specific solutions to improving air quality are local and sustained through public engagement, policy and monitoring. Both the overarching science of air quality and health and local solutions rely on access to reliable, timely air quality data. Over the past year, the OpenAQ community has opened up existing disparate air quality data in 24 countries through an open source platform (openaq.org) so that communities around the world can use it to advance science, public engagement, and policy. We will share stories of communities, from Delhi to Ulaanbaatar and from scientists to journalists, using open air quality data from our platform to advance their fight against air inequality. We will share recent research we have conducted on best practices for engaging different communities and building tools that enable the public to fully unleash the power of open air quality data to fight air inequality. The subsequent open-source tools (github.com/openaq) we have developed from this research and our entire data-sharing platform may be of interest to other open data communities.

OpenAQ: A Platform to Aggregate and Freely Share Global Air Quality Data

NASA Astrophysics Data System (ADS)

Hasenkopf, C. A.; Flasher, J. C.; Veerman, O.; DeWitt, H. L.

2015-12-01

Thousands of ground-based air quality monitors around the world publicly publish real-time air quality data; however, researchers and the public do not have access to this information in the ways most useful to them. Often, air quality data are posted on obscure websites showing only current values, are programmatically inaccessible, and/or are in inconsistent data formats across sites. Yet, historical and programmatic access to such a global dataset would be transformative to several scientific fields, from epidemiology to low-cost sensor technologies to estimates of ground-level aerosol by satellite retrievals. To increase accessibility and standardize this disparate dataset, we have built OpenAQ, an innovative, open platform created by a group of scientists and open data programmers. The source code for the platform is viewable at github.com/openaq. Currently, we are aggregating, storing, and making publicly available real-time air quality data (PM2.5, PM10, SO2, NO2, and O3) via an Application Program Interface (API). We will present the OpenAQ platform, which currently has the following specific capabilities: A continuous ingest mechanism for some of the most polluted cities, generalizable to more sources An API providing data-querying, including ability to filter by location, measurement type and value and date, as well as custom sort options A generalized, chart-based visualization tool to explore data accessible via the API At this stage, we are seeking wider participation and input from multiple research communities in expanding our data retrieval sites, standardizing our protocols, receiving feedback on quality issues, and creating tools that can be built on top of this open platform.

Observational Comparison of Hydroxynitrates from the Southeast United States and the Korean-US Air Quality (KORUS-AQ) Mission

NASA Astrophysics Data System (ADS)

Kim, M. J.; Teng, A.; Crounse, J.; Wennberg, P. O.

2016-12-01

Hydroxynitrates, a multifunctional product of alkene oxidation, can make significant impacts on regional ozone, SOA, and NOX budgets. A product of VOC oxidation and NOx, hydroxynitrates can be key markers of interactions between biogenic and anthropogenic sources, as well as aging of petrochemical emissions. This work compares observations from recent field campaigns across the globe including the Southeast United States (SEAC4RS, SOAS) as well as the recently concluded Korean US Air Quality mission (KORUS-AQ). The KORUS-AQ airborne campaign examined air quality around the Seoul Metropolitan Area (population 25 million) and immediate forested regions, as well as petrochemical processing facilities and shipping activities throughout the Korean peninsula.

4 km Forecasting System to Support DISCOVER-AQ Campaigns: Model Configuration, Testing and Evaluation

NASA Astrophysics Data System (ADS)

Lee, P.; Pan, L.; Kim, H. C.; Chai, T.; Hu, Y.; Tong, D.; Ngan, F.; Wong, D.; Dornblaser, B.; Tanrikulu, S.; Pickering, K. E.

2012-12-01

This work presents the development and evaluation of a high-resolution air quality forecasting system to support two NASA Earth Venture campaigns (DISCOVER-AQ) in 2013. These campaigns aim to further understanding of column-integrated and vertically resolved observations in determining air pollution conditions near the surface (http://science.nasa.gov/missions/discover-aq/). The first one will be carried out in San Joaquin Valley (SJV) in winter and the second one in Houston (HOU) area in late summer. Accurate forecast of pollution plumes is critical for on-site deployment and co-ordination of the various observation platforms. We develop of a fine resolution forecasting system to provide dynamic prediction of the chemical fields over these regions. This system utilizes meteorology fields from the US National Centers for Environmental Prediction North American Model (NAM) that is equipped with an elaborative NAM Data Assimilation System (NDAS) for its Land Surface Model (LSM) and initialization processes. NAM output is used to drive the US EPA Community Multi-scale Air Quality Model (CMAQ) with identical horizontal resolution. The SJV campaign is believed to be subjected to rather high particulate matter loading and possible frequent occurrence of multiple-day fog. NDAS provides advanced methodology to constrain atmospheric stability and soil moisture characteristics. These meteorological parameters are critical for the winter campaign. Special attention is paid to emission modeling for agricultural dust aerosols, which were found important for the SJV area. In contrast to the winter campaign where strong atmospheric stability will likely be a challenge, the HOU campaign in September of 2013 will be challenged with strong atmospheric convection and rather rapid growth of and a sustained deep Planetary Boundary Layer (PBL) during mid-morning and afternoon, respectively. Convection often results in lightning. Wild-fires can contribute significantly to pollution

A Multiplatform Observations of Air Quality in Korea as the Pre-campaign of Korea and US Air Quality (KORUS-AQ) Study.

NASA Astrophysics Data System (ADS)

Park, J. H.; Hong, J.; Hong, Y.; Song, C. K.; Kim, S. K.; Chang, L. S.; Lim, J.; Ahn, J.; Kim, J. Y.; Han, Y. J.; Kim, J.; Park, R.; Lee, G.; Park, J.

2015-12-01

Despite the Korea government's efforts to regulate air pollutant emission for attaining the national air quality standard, current serious dust events and high ozone episodes in summer time remain important societal issues in Korea. In order to make effective policy for air quality attainment, it is contingent upon a thorough understanding of chemical production/loss mechanism of air pollutants and their precursors which drive air quality such as nitrogen oxides (NOX), volatile organic compounds (VOCs), and oxidants (e.g. OH, HO2, RO, RO2, etc.). At present, policy development is constrained by a lack of data for broad suite of chemical species which significantly affect on air quality.During 4 weeks between May and June 2013, the pre-campaign for the Korea and U.S. Air Quality (KORUS-AQ) study took place in multiplatform including fifteen ground sites, one mobile laboratory, and one small air crafts. An integrated research activity covering field observations, chemical transport models, and remote sensing has been intensively conducted. This study was focused on studying photochemistry and nighttime chemistry in urban area and transboundary transport of air pollutants from upwind. Scientific overview and outcomes from the campaign will be presented.

A New Era of Air Quality Monitoring from Space in East Asia: Korea's Geostationary Environmental Monitoring Spectrometer (GEMS) and an Integrated Korea-US Air Quality (KORUS-AQ) Study

NASA Astrophysics Data System (ADS)

Hong, J.; Hong, Y.; Song, C. K.; Kim, S. K.; Chang, L. S.; Lim, J.; Ahn, J.; Park, J. H.; Kim, J. Y.; Han, Y. J.; Kim, J.; Park, R.; Lee, G.; Lefer, B. L.; Al-Saadi, J. A.; Crawford, J. H.

2015-12-01

Due to remarkable economic growth over the last two decades, East Asia has become a region experiencing some of the poorest air quality in the world. In addition to local sources of pollution, the Korea peninsula is downwind of the largest emission sources in East Asia, complicating the understanding of air quality over Korea. Thus, knowing the factors controlling changes in air pollution across urban-rural and marine-continental interfaces, in addition to the contributions from local emissions and transboundary transport, is important for building effective management strategies and improving air quality in East Asia. GEMS (Geostationary Environmental Monitoring Spectrometer) is a satellite instrument planned for launch in 2019 by the Republic of Korea. The instrument will observe East Asia and the western Pacific region, providing real-time monitoring of air quality (e.g. O3, NO2, SO2, HCHO, AOD, etc.) and enabling better scientific understanding of the transboundary transport of air pollutants. The KORUS-AQ (the Korea and U.S. Air Quality) field campaign will take place in May - June 2016 and will employ an integrated observing strategy including multiplatform observations (i.e. ground stations, aircraft, ships, and satellites) and chemical transport models. This mission aims to not only strengthen our knowledge of atmospheric chemistry but also provide important data sets for validating GEMS retrieval algorithms. In preparation for KORUS-AQ, a pre-campaign has been successfully conducted in Korea during early summer 2015 with observations from multiple ground sites and a small aircraft. A brief summary of pre-field campaign results will be presented. Moving forward, the GEMS mission and KORUS-AQ study will lead to a new era of air quality monitoring in East Asia. GEMS will also make critical contributions to the global air quality perspective working in concert with geostationary missions launched by the U.S. (TEMPO: Tropospheric Emissions: Monitoring of

Preliminary Evaluation of Air Quality Model Performance Utilizing Measurements at the University of Houston Moody Tower and others during the TexAQS-II

NASA Astrophysics Data System (ADS)

Byun, D. W.; Rappenglueck, B.; Lefer, B.

2007-12-01

Accurate meteorological and photochemical modeling efforts are necessary to understand the measurements made during the Texas Air Quality Study (TexAQS-II). The main objective of the study is to understand the meteorological and chemical processes of high ozone and regional haze events in the Eastern Texas, including the Houston-Galveston metropolitan area. Real-time and retrospective meteorological and photochemical model simulations were performed to study key physical and chemical processes in the Houston Galveston Area. In particular, the Vertical Mixing Experiment (VME) at the University of Houston campus was performed on selected days during the TexAQS-II. Results of the MM5 meteorological model and CMAQ air quality model simulations were compared with the VME and other TexAQS-II measurements to understand the interaction of the boundary layer dynamics and photochemical evolution affecting Houston air quality.

the Underestimation of Isorene in Houston during the Texas 2013 DISCOVER-AQ Campaign

NASA Astrophysics Data System (ADS)

Choi, Y.; Diao, L.; Czader, B.; Li, X.; Estes, M. J.

2014-12-01

This study applies principal component analysis to aircraft data from the Texas 2013 DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign to characterize isoprene sources over Houston during September 2013. The biogenic isoprene signature appears in the third principal component and anthropogenic signals in the following two. Evaluations of the Community Multiscale Air Quality (CMAQ) model simulations of isoprene with airborne measurements are more accurate for suburban areas than for industrial areas. This study also compares model outputs to eight surface automated gas chromatograph (Auto-GC) measurements near the Houston ship channel industrial area during the nighttime and shows that modeled anthropogenic isoprene is underestimated by a factor of 10.60. This study employs a new simulation with a modified anthropogenic emissions inventory (constraining using the ratios of observed values versus simulated ones) that yields closer isoprene predictions at night with a reduction in the mean bias by 56.93%, implying that model-estimated isoprene emissions from the 2008 National Emission Inventory are underestimated in the city of Houston and that other climate models or chemistry and transport models using the same emissions inventory might also be underestimated in other Houston-like areas in the United States.

Evaluation and Comparison of Methods for Measuring Ozone and NO2 Concentrations in Ambient Air during DISCOVER-AQ

EPA Science Inventory

Ambient evaluations of the various ozone and NO2 methods were conducted during field intensive studies as part of the NASA DISCOVER-AQ project conducted during July 2011 near Baltimore, MD; January – February 2013 in the San Juaquin valley, CA; September 2013 in Houston, TX...

Quantifying TOLNet Ozone Lidar Accuracy During the 2014 DISCOVER-AQ and FRAPPE Campaigns

NASA Technical Reports Server (NTRS)

Wang, Lihua; Newchurch, Michael J.; Alvarez, Raul J., II; Berkoff, Timothy A.; Brown, Steven S.; Carrion, William; De Young, Russell J.; Johnson, Bryan J.; Ganoe, Rene; Gronoff, Guillaume;

Quantifying TOLNet ozone lidar accuracy during the 2014 DISCOVER-AQ and FRAPPÉ campaigns

NASA Astrophysics Data System (ADS)

Wang, Lihua; Newchurch, Michael J.; Alvarez, Raul J., II; Berkoff, Timothy A.; Brown, Steven S.; Carrion, William; De Young, Russell J.; Johnson, Bryan J.; Ganoe, Rene; Gronoff, Guillaume; Kirgis, Guillaume; Kuang, Shi; Langford, Andrew O.; Leblanc, Thierry; McDuffie, Erin E.; McGee, Thomas J.; Pliutau, Denis; Senff, Christoph J.; Sullivan, John T.; Sumnicht, Grant; Twigg, Laurence W.; Weinheimer, Andrew J.

2017-10-01

The Tropospheric Ozone Lidar Network (TOLNet) is a unique network of lidar systems that measure high-resolution atmospheric profiles of ozone. The accurate characterization of these lidars is necessary to determine the uniformity of the network calibration. From July to August 2014, three lidars, the TROPospheric OZone (TROPOZ) lidar, the Tunable Optical Profiler for Aerosol and oZone (TOPAZ) lidar, and the Langley Mobile Ozone Lidar (LMOL), of TOLNet participated in the Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) mission and the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) to measure ozone variations from the boundary layer to the top of the troposphere. This study presents the analysis of the intercomparison between the TROPOZ, TOPAZ, and LMOL lidars, along with comparisons between the lidars and other in situ ozone instruments including ozonesondes and a P-3B airborne chemiluminescence sensor. The TOLNet lidars measured vertical ozone structures with an accuracy generally better than ±15 % within the troposphere. Larger differences occur at some individual altitudes in both the near-field and far-field range of the lidar systems, largely as expected. In terms of column average, the TOLNet lidars measured ozone with an accuracy better than ±5 % for both the intercomparison between the lidars and between the lidars and other instruments. These results indicate that these three TOLNet lidars are suitable for use in air quality, satellite validation, and ozone modeling efforts.

The role of refinery flaring events and bay breezes on a high surface ozone episode during the Houston, Texas DISCOVER-AQ field campaign

NASA Astrophysics Data System (ADS)

Loughner, C.; Follette-Cook, M. B.; Fried, A.; Pickering, K. E.

2015-12-01

The highest observed surface ozone concentrations in the Houston metropolitan area in 2013 occurred on September 25, which coincided with the Texas DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. Surface ozone was elevated throughout the Houston metropolitan area with maximum 8-hour average ozone peaking along the western shore of Galveston Bay, reaching 124 ppbv, almost 50 ppbv above the current EPA standard of 75 ppbv. The NASA P-3B aircraft observed plumes from refinery flares west and northwest of Galveston Bay that were transported over the water. Continental air pollution from the north was transported into the Houston metropolitan area where it mixed with locally generated emissions. A bay breeze circulation formed causing pollutants that were transported out over the water in the morning to recirculate back inland where they mixed with freshly emitted pollution near the bay breeze convergence zone. The highest surface ozone concentrations were reported near the bay breeze front. This ozone episode will be presented using measurements made during the DISCOVER-AQ field campaign and a CMAQ model simulation with integrated source apportionment, which tracks the contribution of emissions source groups and regions on ozone concentrations.

Portable air quality sensor unit for participatory monitoring: an end-to-end VESNA-AQ based prototype

NASA Astrophysics Data System (ADS)

Vucnik, Matevz; Robinson, Johanna; Smolnikar, Miha; Kocman, David; Horvat, Milena; Mohorcic, Mihael

2015-04-01

Key words: portable air quality sensor, CITI-SENSE, participatory monitoring, VESNA-AQ The emergence of low-cost easy to use portable air quality sensors units is opening new possibilities for individuals to assess their exposure to air pollutants at specific place and time, and share this information through the Internet connection. Such portable sensors units are being used in an ongoing citizen science project called CITI-SENSE, which enables citizens to measure and share the data. The project aims through creating citizens observatories' to empower citizens to contribute to and participate in environmental governance, enabling them to support and influence community and societal priorities as well as associated decision making. An air quality measurement system based on VESNA sensor platform was primarily designed within the project for the use as portable sensor unit in selected pilot cities (Belgrade, Ljubljana and Vienna) for monitoring outdoor exposure to pollutants. However, functionally the same unit with different set of sensors could be used for example as an indoor platform. The version designed for the pilot studies was equipped with the following sensors: NO2, O3, CO, temperature, relative humidity, pressure and accelerometer. The personal sensor unit is battery powered and housed in a plastic box. The VESNA-based air quality (AQ) monitoring system comprises the VESNA-AQ portable sensor unit, a smartphone app and the remote server. Personal sensor unit supports wireless connection to an Android smartphone via built-in Wi-Fi. The smartphone in turn serves also as the communication gateway towards the remote server using any of available data connections. Besides the gateway functionality the role of smartphone is to enrich data coming from the personal sensor unit with the GPS location, timestamps and user defined context. This, together with an accelerometer, enables the user to better estimate ones exposure in relation to physical activities, time

Understanding Particulate Matter Dynamics in the San Joaquin Valley during DISCOVER-AQ, 2013

NASA Astrophysics Data System (ADS)

Prabhakar, G.; Zhang, X.; Kim, H.; Parworth, C.; Pusede, S. E.; Wooldridge, P. J.; Cohen, R. C.; Zhang, Q.; Cappa, C. D.

2015-12-01

Air quality in the California San Joaquin Valley (SJV) during winter continues to be the worst in the state, failing EPA's 24-hour standard for particulate matter. Despite our improved understanding of the sources of particulate matter (PM) in the valley, air-quality models are unable to predict PM concentrations accurately. We aim to characterize periods of high particulate matter concentrations in the San Joaquin Valley based on ground and airborne measurements of aerosols and gaseous pollutants, during the DISCOVER-AQ campaign, 2013. A highly instrumented aircraft flew across the SJV making three transects in a repeatable pattern, with vertical spirals over select locations. The aircraft measurements were complemented by ground measurements at these locations, with extensive chemically-speciated measurements at a ground "supersite" at Fresno. Hence, the campaign provided a comprehensive three-dimensional view of the particulate and gaseous pollutants around the valley. The vertical profiles over the different sites indicate significant variability in the concentrations and vertical distribution of PM around the valley, which are most likely driven by differences in the combined effects of emissions, chemistry and boundary layer dynamics at each site. The observations suggest that nighttime PM is dominated by surface emissions of PM from residential fuel combustion, while early morning PM is strongly influenced by mixing of low-level, above-surface, nitrate-rich layers formed from dark chemistry overnight to the surface.

Aerosol Optical Thickness comparisons between NASA LaRC Airborne HSRL and AERONET during the DISCOVER-AQ field campaigns

NASA Astrophysics Data System (ADS)

Scarino, A. J.; Ferrare, R. A.; Burton, S. P.; Hostetler, C. A.; Hair, J. W.; Rogers, R. R.; Berkoff, T.; Cook, A. L.; Harper, D. B.; Hoff, R. M.; Holben, B. N.; Schafer, J.; McGill, M. J.; Yorks, J. E.; Lantz, K. O.; Michalsky, J. J.; Hodges, G.

2013-12-01

The first- and second-generation NASA airborne High Spectral Resolution Lidars (HSRL-1 and HSRL-2) have been deployed on board the NASA Langley Research Center King Air aircraft during the Deriving Information on Surface Conditions from Column and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) field campaigns. These included deployments during July 2011 over Washington, D.C. and Baltimore, MD and during January and February 2013 over the San Joaquin Valley (SJV) of California and also a scheduled deployment during September 2013 over Houston, TX. Measurements of aerosol extinction, backscatter, and depolarization are available from both HSRL-1 and HSRL-2 in coordination with other participating research aircraft and ground sites. These measurements constitute a diverse data set for use in characterizing the spatial and temporal distribution of aerosols, aerosol optical thickness (AOT), as well as the Mixing Layer Height (MLH). HSRL AOT is compared to AOT measured by the Distributed Regional Aerosol Gridded Observation Networks (DRAGON) and long-term AERONET sites. For the 2011 campaign, comparisons of AOT at 532nm between HSRL-1 and AERONET showed excellent agreement (r = 0.98, slope = 1.01, intercept = 0.037) when the King Air flights were within 2.5 km of the ground site and 10 min from the retrieval time. The comparison results are similar for the 2013 DISCOVER-AQ campaign in the SJV. Additional ground-based (MPL) and airborne (CPL) lidar data were used to help screen for clouds in the AERONET observations during the SJV portion. AOT values from a Multi-Filter Rotating Shadowband Radiometer (MFRSR) located at the Porterville, CA site during the SJV campaign are also compared to HSRL-2 AOT. Lastly, using the MLH retrieved from HSRL aerosol backscatter profiles, we describe the distribution of AOT relative to the MLH.

Deriving Surface NO2 Mixing Ratios from DISCOVER-AQ ACAM Observations: A Method to Assess Surface NO2 Spatial Variability

NASA Astrophysics Data System (ADS)

Silverman, M. L.; Szykman, J.; Chen, G.; Crawford, J. H.; Janz, S. J.; Kowalewski, M. G.; Lamsal, L. N.; Long, R.

2015-12-01

Studies have shown that satellite NO2 columns are closely related to ground level NO2 concentrations, particularly over polluted areas. This provides a means to assess surface level NO2 spatial variability over a broader area than what can be monitored from ground stations. The characterization of surface level NO2 variability is important to understand air quality in urban areas, emissions, health impacts, photochemistry, and to evaluate the performance of chemical transport models. Using data from the NASA DISCOVER-AQ campaign in Baltimore/Washington we calculate NO2 mixing ratios from the Airborne Compact Atmospheric Mapper (ACAM), through four different methods to derive surface concentration from column measurements. High spectral resolution lidar (HSRL) mixed layer heights, vertical P3B profiles, and CMAQ vertical profiles are used to scale ACAM vertical column densities. The derived NO2 mixing ratios are compared to EPA ground measurements taken at Padonia and Edgewood. We find similar results from scaling with HSRL mixed layer heights and normalized P3B vertical profiles. The HSRL mixed layer heights are then used to scale ACAM vertical column densities across the DISCOVER-AQ flight pattern to assess spatial variability of NO2 over the area. This work will help define the measurement requirements for future satellite instruments.

Camx Ozone Source Attribution in the Eastern United States Using Guidance from Observations During DISCOVER-AQ Maryland

NASA Technical Reports Server (NTRS)

Goldberg, Daniel L.; Vinciguerra, Timothy P.; Anderson, Daniel C.; Hembeck, Linda; Canty, Timothy P.; Ehrman, Sheryl H.; Martins, Douglas K.; Stauffer, Ryan M.; Thompson, Anne M.; Salawitch, Ross J.;

Vertical Profiles of Light-Absorbing Aerosol: A Combination of In-situ and AERONET Observations during NASA DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Ziemba, L. D.; Beyersdorf, A. J.; Chen, G.; Corr, C.; Crumeyrolle, S.; Giles, D. M.; Holben, B. N.; Hudgins, C.; Martin, R.; Moore, R.; Shook, M.; Thornhill, K. L., II; Winstead, E.; Anderson, B. E.

2014-12-01

Understanding the vertical profile of atmospheric aerosols plays a vital role in utilizing spaceborne, column-integrated satellite observations. The properties and distribution of light-absorbing aerosol are particularly uncertain despite significant air quality and climate ramifications. Advanced retrieval algorithms are able to derive complex aerosol properties (e.g., wavelength-dependent absorption coefficient and single scattering albedo) from remote-sensing measurements, but quantitative relationships to surface conditions remain a challenge. Highly systematic atmospheric profiling during four unique deployments for the NASA DISCOVER-AQ project (Baltimore, MD, 2011; San Joaquin Valley, CA, 2013; Houston, TX, 2013; Denver, CO, 2014) allow statistical assessment of spatial, temporal, and source-related variability for light-absorbing aerosol properties in these distinct regions. In-situ sampling in conjunction with a dense network of AERONET sensors also allows evaluation of the sensitivity, limitations, and advantages of remote-sensing data products over a wide range of conditions. In-situ aerosol and gas-phase observations were made during DISCOVER-AQ aboard the NASA P-3B aircraft. Aerosol absorption coefficients were measured by a Particle Soot Absorption Photometer (PSAP). Approximately 200 profiles for each of the four deployments were obtained, from the surface (25-300m altitude) to 5 km, and are used to calculate absorption aerosol optical depths (AAODs). These are quantitatively compared to AAOD derived from AERONET Level 1.5 retrievals to 1) explore discrepancies between measurements, 2) quantify the fraction of AAOD that exists directly at the surface and is often missed by airborne sampling, and 3) evaluate the potential for deriving ground-level black carbon (BC) concentrations for air quality prediction. Aerosol size distributions are used to assess absorption contributions from mineral dust, both at the surface and aloft. SP2 (Single Particle Soot

Evaluation and intercomparison of air quality forecasts over Korea during the KORUS-AQ campaign

NASA Astrophysics Data System (ADS)

Lee, Seungun; Park, Rokjin J.; Kim, Soontae; Song, Chul H.; Kim, Cheol-Hee; Woo, Jung-Hun

2017-04-01

We evaluate and intercompare ozone and aerosol simulations over Korea during the KORUS-AQ campaign, which was conducted in May-June 2016. Four global and regional air quality models participated in the campaign and provided daily air quality forecasts over Korea to guide aircraft flight paths for detecting air pollution events over Korean peninsula and its nearby oceans. We first evaluate the model performance by comparing simulated and observed hourly surface ozone and PM2.5 concentrations at ground sites in Korea and find that the models successfully capture intermittent air pollution events and reproduce the daily variation of ozone and PM2.5 concentrations. However, significant underestimates of peak ozone concentrations in the afternoon are also found in most models. Among chemical constituents of PM2.5, the models typically overestimate observed nitrate aerosol concentrations and underestimate organic aerosol concentrations, although the observed mass concentrations of PM2.5 are seemingly reproduced by the models. In particular, all models used the same anthropogenic emission inventory (KU-CREATE) for daily air quality forecast, but they show a considerable discrepancy for ozone and aerosols. Compared to individual model results, the ensemble mean of all models shows the best performance with correlation coefficients of 0.73 for ozone and 0.57 for PM2.5. We here investigate contributing factors to the discrepancy, which will serve as a guidance to improve the performance of the air quality forecast.

CAMx Ozone Source Attribution in the Eastern United States using Guidance from Observations during DISCOVER-AQ Maryland

PubMed Central

Goldberg, Daniel L.; Vinciguerra, Timothy P.; Anderson, Daniel C.; Hembeck, Linda; Canty, Timothy P.; Ehrman, Sheryl H.; Martins, Douglas K.; Stauffer, Ryan M.; Thompson, Anne M.; Salawitch, Ross J.; Dickerson, Russell R.

2018-01-01

A Comprehensive Air-Quality Model with Extensions (CAMx) version 6.10 simulation was assessed through comparison with data acquired during NASA’s 2011 DISCOVER-AQ Maryland field campaign. Comparisons for the baseline simulation (CB05 chemistry, EPA 2011 National Emissions Inventory) show a model overestimate of NOy by +86.2% and an underestimate of HCHO by −28.3%. We present a new model framework (CB6r2 chemistry, MEGAN v2.1 biogenic emissions, 50% reduction in mobile NOx, enhanced representation of isoprene nitrates) that better matches observations. The new model framework attributes 31.4% more surface ozone in Maryland to electric generating units (EGUs) and 34.6% less ozone to on-road mobile sources. Surface ozone becomes more NOx-limited throughout the eastern United States compared to the baseline simulation. The baseline model therefore likely underestimates the effectiveness of anthropogenic NOx reductions as well as the current contribution of EGUs to surface ozone. PMID:29618849

CAMx Ozone Source Attribution in the Eastern United States using Guidance from Observations during DISCOVER-AQ Maryland.

PubMed

Goldberg, Daniel L; Vinciguerra, Timothy P; Anderson, Daniel C; Hembeck, Linda; Canty, Timothy P; Ehrman, Sheryl H; Martins, Douglas K; Stauffer, Ryan M; Thompson, Anne M; Salawitch, Ross J; Dickerson, Russell R

2016-03-16

A Comprehensive Air-Quality Model with Extensions (CAMx) version 6.10 simulation was assessed through comparison with data acquired during NASA's 2011 DISCOVER-AQ Maryland field campaign. Comparisons for the baseline simulation (CB05 chemistry, EPA 2011 National Emissions Inventory) show a model overestimate of NO y by +86.2% and an underestimate of HCHO by -28.3%. We present a new model framework (CB6r2 chemistry, MEGAN v2.1 biogenic emissions, 50% reduction in mobile NO x , enhanced representation of isoprene nitrates) that better matches observations. The new model framework attributes 31.4% more surface ozone in Maryland to electric generating units (EGUs) and 34.6% less ozone to on-road mobile sources. Surface ozone becomes more NO x -limited throughout the eastern United States compared to the baseline simulation. The baseline model therefore likely underestimates the effectiveness of anthropogenic NO x reductions as well as the current contribution of EGUs to surface ozone.

Sources and composition of PM2.5 in the Colorado Front Range during the DISCOVER-AQ study

NASA Astrophysics Data System (ADS)

Valerino, M. J.; Johnson, J. J.; Izumi, J.; Orozco, D.; Hoff, R. M.; Delgado, R.; Hennigan, C. J.

2017-01-01

Measurements of particulate matter (PM2.5) chemical composition were carried out in Golden, CO, during the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) field study. Chemical composition was dominated by organic compounds, which comprised an average of 75% of the PM2.5 mass throughout the study. Most of the organic matter was secondary (i.e., secondary organic aerosol) and appears to derive predominantly from regional sources, rather than the Denver metropolitan area. The concentration and composition of PM2.5 in Golden were strongly influenced by highly regular wind patterns and the site's close proximity to the mountains ( 5 km). This second factor may be the cause of distinct differences between observations in Golden and those in downtown Denver, despite a distance between the sites of only 15 km. Concentrations of aerosol nitrate, ammonium, and elemental carbon increased significantly during the daytime when the winds were from the northeast, indicating a strong local source for these compounds. Local sources of dust appeared to minimally impact the Golden site, although this was not likely representative of other conditions in the Colorado Front Range. Conversely, dust that had undergone long-range transport from the southwestern U.S. likely impacted the entire Colorado Front Range, including Golden. During this event, water-soluble Ca2+ concentrations exceeded 1 µg m-3, and the PM2.5/PM10 ratio reached its lowest level throughout the study. The long-range transport of wildfire emissions also impacted the Colorado Front Range for 1-2 days during DISCOVER-AQ. The smoke event was characterized by high concentrations of organics and water-soluble K+. The results show a complex array of sources, and atmospheric processes influence summertime PM in the Colorado Front Range.

Interpreting Lidar Measurements to Better Estimate Surface PM2.S in Study Regions of DISCOVER-AQ

NASA Technical Reports Server (NTRS)

Chu, D. A.; Ferrare, Richard; Welton, Judd; Hostetler, Chris; Hair, John; Szykman, James; Al-Saadi, Jay; Tsai, Tzuchin

2011-01-01

The use of satellite AOD data to estimate surface PM2.5 has been broadly studied in various regions. Some showed good results while some showed relatively poor with the simple relationship between AOD and PM2.5. The key factor is the aerosol vertical distribution. Lidar extinction profiles provide insights into the aerosol mixing not only in the boundary layer but also quantifying residual aerosol abundance above boundary layer with e-folding scale height. The normalizing AOD by hazy layer height is proven better in correlating with PM2.5. In other words, extinction measurements near the surface can be a proxy for surface PM2.5. In this study, we will use NASA airborne HSRL (High Spectral Resolution Lidar) during SJV2007 (San Joaquin Valley, February 2007) and surface MPLNet (Micropulse Lidar Network) at GSFC between 2007 and 2010 to characterize the relationship for the DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) field experiments; the first over Baltimore-Washington was conducted in July 2011.

DISCOVER-AQ Second Tour

Atmospheric Science Data Center

2015-03-05

...   Air Quality is vital to our everyday and long term health. Over the years, scientists have been able to develop satellites that ... Air Quality is vital to our everyday and long term health. Over the years, scientists have been able to develop satellites that ...

Improved Satellite-based Photosysnthetically Active Radiation (PAR) for Air Quality Studies

NASA Astrophysics Data System (ADS)

Pour Biazar, A.; McNider, R. T.; Cohan, D. S.; White, A.; Zhang, R.; Dornblaser, B.; Doty, K.; Wu, Y.; Estes, M. J.

2015-12-01

One of the challenges in understanding the air quality over forested regions has been the uncertainties in estimating the biogenic hydrocarbon emissions. Biogenic volatile organic compounds, BVOCs, play a critical role in atmospheric chemistry, particularly in ozone and particulate matter (PM) formation. In southeastern United States, BVOCs (mostly as isoprene) are the dominant summertime source of reactive hydrocarbon. Despite significant efforts in improving BVOC estimates, the errors in emission inventories remain a concern. Since BVOC emissions are particularly sensitive to the available photosynthetically active radiation (PAR), model errors in PAR result in large errors in emission estimates. Thus, utilization of satellite observations to estimate PAR can help in reducing emission uncertainties. Satellite-based PAR estimates rely on the technique used to derive insolation from satellite visible brightness measurements. In this study we evaluate several insolation products against surface pyranometer observations and offer a bias correction to generate a more accurate PAR product. The improved PAR product is then used in biogenic emission estimates. The improved biogenic emission estimates are compared to the emission inventories over Texas and used in air quality simulation over the period of August-September 2013 (NASA's Discover-AQ field campaign). A series of sensitivity simulations will be performed and evaluated against Discover-AQ observations to test the impact of satellite-derived PAR on air quality simulations.

Policy implications of KORUS-AQ

NASA Astrophysics Data System (ADS)

Kim, J.; Chang, L.; Ahn, J.

2017-12-01

Under the leadership of NIER(S. Korea) and NASA(US), Korea-United States Air Quality Study(KORUS-AQ) assembled a large team of measurement and modeling experts to conduct a field study in Korea. The KORUS-AQ study collected detailed measurements from aircrafts, groundsites, and ships during 1 May and 10 June of 2016. Observations were guided by model forecasts of meteorology and air quality, but they also serve to evaluate the performance of these models as part of the ongoing analysis of KORUS-AQ data. And for the understanding to public, we summarized preliminary findings for the following questions. - Can we identify a) the portion of aerosol derived from secondary production in SMA and across Korea, and b) the major sources and factors controlling its variation? - Is ozone formation in Seoul NOx limited or VOC limited? Can we determine the biogenic or natural contributions to ozone production? - How well do KORUS-AQ observations support current emissions estimations by magnitude and sector? - How significant is the impact of the large point sources along the west coast to the air quality of SMA temporally and spatially? - How is Seoul affected by transport of air pollution from sources from regional to continental to hemispheric scales? In the presentation, brief results will be introduced with some directions for the policy and future plans.

Aerosol Composition and Variability in Baltimore Measured during DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Beyersdorf, A. J.; Ziemba, L. D.; Chen, G.; Thornhill, K. L.; Winstead, E. L.; Diskin, G. S.; Chatfield, R. B.; Natraj, V.; Anderson, B. E.

2012-12-01

In order to relate satellite-based measurements of aerosols to ground-level air quality, the correlation between aerosol optical properties (wavelength-dependent scattering and absorption measured by satellites) and mass measurements of aerosol loading (i.e. PM2.5 used for air quality monitoring) must be understood. This connection varies with many factors including those specific to the aerosol type (such as composition, size, hygroscopicity, and mass scattering and absorption efficiencies) and to the surrounding atmosphere (such as temperature, relative humidity and altitude). The DISCOVER-AQ (Deriving Information on Surface conditions from COlumn and VERtically resolved observations relevant to Air Quality) project was designed to provide a unique dataset for determining variability in and correlations between aerosol loading, composition, optical properties and meteorological conditions. Extensive in-situ profiling of the lower atmosphere in the Baltimore-Washington D.C. region was performed during fourteen flights during July 2011. Identical flight plans and profile locations throughout the campaign provide meaningful statistics for analysis. Measured aerosol mass was composed primarily of ammonium sulfate (campaign average of 36%) and water-soluble organics (58%). A distinct difference in composition was related to aerosol loading with high-loading days having a proportionally larger percentage of ammonium sulfate (up to 60%). This composition shift causes a change in the water-uptake potential (hygroscopicity) of the aerosols with higher relative organic composition decreasing water-uptake. On average, sulfate mass increased during the day due to increased photochemistry, while organics decreased. Analysis of the linkage between aerosol loading and optical properties was also performed. The absorption by black carbon was dependent on the amount of organic coating with an increase in mass absorption efficiency from 7.5 m2/g for bare soot to 16 m2/g at an

Rural southeast Texas air quality measurements during the 2006 Texas Air Quality Study.

PubMed

Schade, Gunnar W; Khan, Siraj; Park, Changhyoun; Boedeker, Ian

2011-10-01

The authors conducted air quality measurements of the criteria pollutants carbon monoxide, nitrogen oxides, and ozone together with meteorological measurements at a park site southeast of College Station, TX, during the 2006 Texas Air Quality Study II (TexAQS). Ozone, a primary focus of the measurements, was above 80 ppb during 3 days and above 75 ppb during additional 8 days in summer 2006, suggestive of possible violations of the ozone National Ambient Air Quality Standard (NAAQS) in this area. In concordance with other air quality measurements during the TexAQS II, elevated ozone mixing ratios coincided with northerly flows during days after cold front passages. Ozone background during these days was as high as 80 ppb, whereas southerly air flows generally provided for an ozone background lower than 40 ppb. Back trajectory analysis shows that local ozone mixing ratios can also be strongly affected by the Houston urban pollution plume, leading to late afternoon ozone increases of as high as 50 ppb above background under favorable transport conditions. The trajectory analysis also shows that ozone background increases steadily the longer a southern air mass resides over Texas after entering from the Gulf of Mexico. In light of these and other TexAQS findings, it appears that ozone air quality is affected throughout east Texas by both long-range and regional ozone transport, and that improvements therefore will require at least a regionally oriented instead of the current locally oriented ozone precursor reduction policies.

Hourly air pollution concentrations and their important predictors over Houston, Texas using deep neural networks: case study of DISCOVER-AQ time period

NASA Astrophysics Data System (ADS)

Eslami, E.; Choi, Y.; Roy, A.

2017-12-01

Air quality forecasting carried out by chemical transport models often show significant error. This study uses a deep-learning approach over the Houston-Galveston-Brazoria (HGB) area to overcome this forecasting challenge, for the DISCOVER-AQ period (September 2013). Two approaches, deep neural network (DNN) using a Multi-Layer Perceptron (MLP) and Restricted Boltzmann Machine (RBM) were utilized. The proposed approaches analyzed input data by identifying features abstracted from its previous layer using a stepwise method. The approaches predicted hourly ozone and PM in September 2013 using several predictors of prior three days, including wind fields, temperature, relative humidity, cloud fraction, precipitation along with PM, ozone, and NOx concentrations. Model-measurement comparisons for available monitoring sites reported Indexes of Agreement (IOA) of around 0.95 for both DNN and RBM. A standard artificial neural network (ANN) (IOA=0.90) with similar architecture showed poorer performance than the deep networks, clearly demonstrating the superiority of the deep approaches. Additionally, each network (both deep and standard) performed significantly better than a previous CMAQ study, which showed an IOA of less than 0.80. The most influential input variables were identified using their associated weights, which represented the sensitivity of ozone to input parameters. The results indicate deep learning approaches can achieve more accurate ozone forecasting and identify the important input variables for ozone predictions in metropolitan areas.

Using Satellite Aerosol Retrievals to Monitor Surface Particulate Air Quality

NASA Technical Reports Server (NTRS)

Levy, Robert C.; Remer, Lorraine A.; Kahn, Ralph A.; Chu, D. Allen; Mattoo, Shana; Holben, Brent N.; Schafer, Joel S.

2011-01-01

The MODIS and MISR aerosol products were designed nearly two decades ago for the purpose of climate applications. Since launch of Terra in 1999, these two sensors have provided global, quantitative information about column-integrated aerosol properties, including aerosol optical depth (AOD) and relative aerosol type parameters (such as Angstrom exponent). Although primarily designed for climate, the air quality (AQ) community quickly recognized that passive satellite products could be used for particulate air quality monitoring and forecasting. However, AOD and particulate matter (PM) concentrations have different units, and represent aerosol conditions in different layers of the atmosphere. Also, due to low visible contrast over brighter surface conditions, satellite-derived aerosol retrievals tend to have larger uncertainty in urban or populated regions. Nonetheless, the AQ community has made significant progress in relating column-integrated AOD at ambient relative humidity (RH) to surface PM concentrations at dried RH. Knowledge of aerosol optical and microphysical properties, ambient meteorological conditions, and especially vertical profile, are critical for physically relating AOD and PM. To make urban-scale maps of PM, we also must account for spatial variability. Since surface PM may vary on a finer spatial scale than the resolution of standard MODIS (10 km) and MISR (17km) products, we test higher-resolution versions of MODIS (3km) and MISR (1km research mode) retrievals. The recent (July 2011) DISCOVER-AQ campaign in the mid-Atlantic offers a comprehensive network of sun photometers (DRAGON) and other data that we use for validating the higher resolution satellite data. In the future, we expect that the wealth of aircraft and ground-based measurements, collected during DISCOVER-AQ, will help us quantitatively link remote sensed and ground-based measurements in the urban region.

An overview of the KORUS-AQ field study

NASA Astrophysics Data System (ADS)

Chang, L.; Ahn, J.; Park, J.; Hong, J.; Hong, Y.; Song, C. K.; Kim, S. K.; Park, R.; Kim, J.; Lefer, B. L.; Crawford, J. H.; Al-Saadi, J. A.

2016-12-01

Korea peninsular is under the influence of the largest emission source in East Asia in addition to local emissions, complicating effective pollution control by government. An international air quality field campaign in Korea, KORUS-AQ, was conducted during 6 weeks between May-June 2016, which was led by the National Institute of Environmental Research (NIER) of Korea and the National Aeronautics and Space Administration (NASA) of the United States. The KORUS-AQ focused on the air quality of SMA with the aim of characterizing chemical evolution, improving emission inventories, assessing trans-boundary contribution and validating satellite application. 133 research teams from 80 organizations in both Korea and U.S.A were involved in KORUS-AQ with 3 research aircrafts, 2 research vessels and 16 ground sites constituting multi-platform observations framework. KORUS-AQ campaign also served the preparation for the future launch of geostationary satellite instruments; GEMS (Geostationary Environmental Monitoring Spectrometer), TEMPO(Tropospheric Emissions: Monitoring of Pollution) and Sentinel-4 which will provide real-time air quality (e.g. O3, NO2, SO2, HCHO, AOD, etc.) data enabling us better understanding of air quality in globe.

Spatiotemporal Variability in Observations of Urban Mixed-Layer Heights from Surface-based Lidar Systems during DISCOVER-AQ 2011

NASA Astrophysics Data System (ADS)

Lewis, J. R.; Banks, R. F.; Berkoff, T.; Welton, E. J.; Joseph, E.; Thompson, A. M.; Decola, P.; Hegarty, J. D.

2015-12-01

Accurate characterization of the planetary boundary layer height is crucial for numerical weather prediction, estimating pollution emissions and modeling air quality. More so, given the increasing trend in global urban populations, there is a growing need to improve our understanding of the urban boundary layer structure and development. The Deriving Information on Surface conditions from COlumn and VERtically resolved observations relevant to Air Quality (DISCOVER-AQ) 2011 field campaign, which took place in the Baltimore-Washington DC region, offered a unique opportunity to study boundary layer processes in an urban area using a geographically dense collection of surface-based lidar systems (see figure). Lidars use aerosols as tracers for atmospheric boundary layer dynamics with high vertical and temporal resolutions. In this study, we use data from two permanent Micropulse Lidar Network (MPLNET) sites and five field deployed Micropulse lidar (MPL) systems in order to observe spatiotemporal variations in the daytime mixed layer height. We present and compare lidar-derived retrievals of the mixed layer height using two different methods. The first method uses the wavelet covariance transform and a "fuzzy logic" attribution scheme in order to determine the mixed layer height. The second method uses an objective approach utilizing a time-adaptive extended Kalman filter. Independent measurements of the boundary layer height are obtained using profiles from ozonesonde launches at the Beltsville and Edgewood sites for comparison with lidar observations.

Using aircraft and satellite observations to improve regulatory air quality models

NASA Astrophysics Data System (ADS)

Canty, T. P.; Vinciguerra, T.; Anderson, D. C.; Carpenter, S. F.; Goldberg, D. L.; Hembeck, L.; Montgomery, L.; Liu, X.; Salawitch, R. J.; Dickerson, R. R.

2014-12-01

Federal and state agencies rely on EPA approved models to develop attainment strategies that will bring states into compliance with the National Ambient Air Quality Standards (NAAQS). We will describe modifications to the Community Multi-Scale Air Quality (CMAQ) model and Comprehensive Air Quality Model with Extensions (CAMx) frameworks motivated by analysis of NASA satellite and aircraft measurements. Observations of tropospheric column NO2 from OMI have already led to the identification of an important deficiency in the chemical mechanisms used by models; data collected during the DISCOVER-AQ field campaign has been instrumental in devising an improved representation of the chemistry of nitrogen species. Our recent work has focused on the use of: OMI observations of tropospheric O3 to assess and improve the representation of boundary conditions used by AQ models, OMI NO2 to derive a top down NOx emission inventory from commercial shipping vessels that affect air quality in the Eastern U.S., and OMI HCHO to assess the C5H8 emission inventories provided by bioegenic emissions models. We will describe how these OMI-driven model improvements are being incorporated into the State Implementation Plans (SIPs) being prepared for submission to EPA in summer 2015 and how future modeling efforts may be impacted by our findings.

Markers for Chinese and Korean Air Masses: Halocarbons and Other Trace Gases Measured During KORUS-AQ

NASA Astrophysics Data System (ADS)

Blake, N. J.; Blake, D. R.; Meinardi, S.; Simpson, I. J.; Hughes, S.; Barletta, B.; Fleming, L.; Vizenor, N.; Schroeder, J.; Emmons, L. K.; Knote, C. J.

2017-12-01

The UC-Irvine Whole Air Sampler (WAS) collected a total of 2650 samples aboard the NASA DC-8 aircraft in support of the May-June 2016 field deployment phase of the KORUS-AQ mission: An International Cooperative Air Quality Field Study in Korea. Here we employ our trace gas measurements, along with CAM-chem tracers and back-trajectories to identify source regions during KORUS-AQ, with a focus on air masses which indicate Chinese and/or Korean origin. During KORUS-AQ we flew mostly over and around the Korean Peninsula with the intent of characterising Korean sources, but Chinese influence was observed offshore near the surface of the West Sea during several KORUS-AQ flights - in accord with forecast predictions from CAM-chem model runs. Unlike previous missions in the Asian region such as TRACE-P (2001), we found that halon-1211 (H-1211) is no longer a useful indicator of air masses from China because of production decline. By contrast, mixing ratios of the long-lived halocarbons carbon tetrachloride (CCl4) and chlorofluorocarbon-113 (CFC-113) were more strongly enhanced in air masses intercepted from China compared to Korea. We will use these tracers, the shorter-lived halocarbons, dichloromethane (CH2Cl2) and methyl chloride (CH3Cl), as well as the sulfur gas carbonyl sulfide (COS) and others, to characterize different regional air mass origins and their sources.

An Overview of Atmospheric Chemistry and Air Quality Modeling

NASA Technical Reports Server (NTRS)

Johnson, Matthew S.

2017-01-01

This presentation will include my personal research experience and an overview of atmospheric chemistry and air quality modeling to the participants of the NASA Student Airborne Research Program (SARP 2017). The presentation will also provide examples on ways to apply airborne observations for chemical transport (CTM) and air quality (AQ) model evaluation. CTM and AQ models are important tools in understanding tropospheric-stratospheric composition, atmospheric chemistry processes, meteorology, and air quality. This presentation will focus on how NASA scientist currently apply CTM and AQ models to better understand these topics. Finally, the importance of airborne observation in evaluating these topics and how in situ and remote sensing observations can be used to evaluate and improve CTM and AQ model predictions will be highlighted.

Canadian Operational Air Quality Forecasting Systems: Status, Recent Progress, and Challenges

NASA Astrophysics Data System (ADS)

Pavlovic, Radenko; Davignon, Didier; Ménard, Sylvain; Munoz-Alpizar, Rodrigo; Landry, Hugo; Beaulieu, Paul-André; Gilbert, Samuel; Moran, Michael; Chen, Jack

2017-04-01

ECCC's Canadian Meteorological Centre Operations (CMCO) division runs a number of operational air quality (AQ)-related systems that revolve around the Regional Air Quality Deterministic Prediction System (RAQDPS). The RAQDPS generates 48-hour AQ forecasts and outputs hourly concentration fields of O3, PM2.5, NO2, and other pollutants twice daily on a North-American domain with 10-km horizontal grid spacing and 80 vertical levels. A closely related AQ forecast system with near-real-time wildfire emissions, known as FireWork, has been run by CMCO during the Canadian wildfire season (April to October) since 2014. This system became operational in June 2016. The CMCO`s operational AQ forecast systems also benefit from several support systems, such as a statistical post-processing model called UMOS-AQ that is applied to enhance forecast reliability at point locations with AQ monitors. The Regional Deterministic Air Quality Analysis (RDAQA) system has also been connected to the RAQDPS since February 2013, and hourly surface objective analyses are now available for O3, PM2.5, NO2, PM10, SO2 and, indirectly, the Canadian Air Quality Health Index. As of June 2015, another version of the RDAQA has been connected to FireWork (RDAQA-FW). For verification purposes, CMCO developed a third support system called Verification for Air QUality Models (VAQUM), which has a geospatial relational database core and which enables continuous monitoring of the AQ forecast systems' performance. Urban environments are particularly subject to AQ pollution. In order to improve the services offered, ECCC has recently been investing efforts to develop a high resolution air quality prediction capability for urban areas in Canada. In this presentation, a comprehensive description of the ECCC AQ systems will be provided, along with a discussion on AQ systems performance. Recent improvements, current challenges, and future directions of the Canadian operational AQ program will also be discussed.

Verification of CMAQ modeling with Discover-AQ campaigns against measurements and efficacy of emission inversion modeling

NASA Astrophysics Data System (ADS)

Lee, P.; Tang, Y.; Pan, L.; Szykman, J.; Plessel, T.; Tong, D.; Liu, Q.

2015-12-01

NASA has led a few DISCOVER-AQ campaigns in recent years: (1) Baltimore/Washington in July 2011, (2) Central valley, CA in January - February 2013, (3) Houston, TX in September 2013, and co-led with NCAR (4) Front Range, CO in July - August 2014. NOAA Air Resources Laboratory has participated in all these campaigns in the role of air quality forecasting support. For some of these campaigns post analyses were performed with the possible help of after-the-fact observed data from satellite retrieved radiances to constrain emissions through the Community Radiative Transfer Model (CRTM) developed at the Joint Center for Satellite Data Assimilation. It is our experience that despite the vastly different chemical regime, season, terrain, and meteorological conditions of the domain for the campaigns, we found that the emissions input and the U.S. EPA Community Air Quality model (CMAQ), the forecasting chemical transport model used to generate the forecast had severely under-estimated formaldehyde (HCHO), and carbon monoxide (CO) aloft between surface and the middle of the free troposphere - 500 hPa. Post analyses point to two strong suspects of these deficiencies: (a) emission projection fed into CMAQ, and/or (b) erroneously fast removal of the species. We investigate both of these potential deficiencies and for the former possible reason we looked into data assimilation and possible inverse modeling to adjust emission projection for CMAQ. We will elaborate more on the CRTM which plays a critical role in this aspect of remedying erroneous inputs to CMAQ. In addition, we will utilize some satellite products to improve initial fields of aerosols and CO for air quality forecasting. Suomi NPP VIIRS aerosol optical depth (AOD) environmental data record (EDR) delivers global aerosol information daily. The Unique CrIS/ATMS Processing System (NUCAPS) operationally generates vertical profiles of atmospheric carbonate EDRs (CO, CO2, and CH4) and ozone during day and night. The AOD

Open Imaging Nephelometer Scattering Measurements from the 2014 Discover-AQ Field Mission

NASA Astrophysics Data System (ADS)

Espinosa, R.; Orozco, D.; Dolgos, G.; Martins, J. V.

2014-12-01

After greenhouse gases, aerosols are thought to have the largest contribution to total atmospheric radiative forcing, but they are frequently cited as the single largest source of uncertainty among all anthropogenic radiative forcing components. Remote sensing allows for global measurements of aerosol properties, however validation of these measurements and the climatological assumptions used in their retrieval algorithms require high quality in situ sampling. The Laboratory for Aerosols, Clouds and Optics (LACO) at the University of Maryland Baltimore County (UMBC) has developed the Imaging Nephelometer, a novel and highly accurate instrument concept designed to significantly aid in situ optical scattering measurements. Imaging Nephelometers allow for measurements of scattering coefficient, phase function and polarized phase function over a wide angular range of 2 to 178 degrees with an angular resolution of less than half of a degree. The simple layout of these devices also permits the construction of an instrument that is compact enough to be deployed on a variety of airborne platforms. Additionally, a version of this instrument that is capable of in situ sampling in open-air, free from sample biases potentially introduced by an inlet or containment apparatus, has recently been constructed. This instrument, known as the Open Imaging NEPHelometer (OI-NEPH), was flown on the P3 aircraft in the summer of 2014 during the Colorado portion of the Discover-AQ field mission (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality). This presentation will focus on the results of the OI-NEPH's successful science flights during this field experiment. The P3's flights during this mission focused primarily on vehicle, agriculture, biomass burning and industrial processing emissions over the Colorado Front Range. Emphasis will be placed on any observed differences in scattering properties between the measurements

The Impact of TexAQS 2000 on Air Quality Planning in Houston

NASA Astrophysics Data System (ADS)

Thomas, J. W.; Price, J. H.

2002-12-01

Before the Texas 2000 Air Quality Study (TexAQS 2000) the State used the Urban Airshed Model to model nine different episodes in Houston with very poor results: only one episode met EPA model performance criteria. Questions existed regarding emissions uncertainties, meteorological modeling, and model chemistry. NOAA, DOE, and SOS led more than 35 organizations and 250 investigators who participated in TexAQS 2000. Major findings from TexAQS 2000 are: 1. There are two types of meteorological patterns that lead to ozone episodes in the Houston area: (i) stagnation associated with the sea breeze flow reversal causes a pool of industrial emissions and ozone to accumulate, then to move across the city as the wind flow picks up and (ii) plumes of ozone form when relatively persistent winds carry the emissions away from the city and industrial areas. 2. The chemistry that produces high ozone concentrations and rapid rises in ozone in the Houston area has been explained: multiple investigators in TexAQS 2000 have documented more rapid and more efficient formation of ozone in the plume from the Houston industrial area than any of them has observed in any previous field study. Houston's exceptionally rapid ozone formation arises from large amounts of anthropogenic VOCs in the atmosphere, often from the same plants that provide sufficient NOx. 3. This rapid and efficient ozone formation results most often from the presence of a specific subclass of hydrocarbons called light olefins, primarily ethylene and propylene. 4. Sometimes it is other specific hydrocarbons that cause the rapid formation of high concentrations of ozone, and sometimes it is just the total mass of a lot of relatively unreactive hydrocarbons. 5. The current emissions inventory for ethylene and propylene, as well as other VOCs, underestimates their routine emissions by a factor of roughly five to ten or perhaps even more. 6. It is not clear whether the emissions causing Houston's rapid ozone formation are

Site Location Details, Air Pollution Monitoring Equipment Used, Aircraft Flight Path Information, and Deployment Configuration for the DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) Field Campaign in Colorado: Summer 2014

EPA Science Inventory

For EPA, this Summer 2014, Denver CO, DISCOVER-AQ field research activity focused on assessing Federal Reference Methods (FRMs) and Federal Equivalent Methods (FEMs) for ozone (O3) and Nitrogen Dioxide (NO2), while comparing their operational performance to each other and to smal...

Higher Surface Ozone Concentrations Over the Chesapeake Bay than Over the Adjacent Land: Observations and Models from the DISCOVER-AQ and CBODAQ Campaigns

NASA Technical Reports Server (NTRS)

Goldberg, Daniel L.; Loughner, Christopher P.; Tzortziou, Maria; Stehr, Jeffrey W.; Pickering, Kenneth E.; Marufu, Lackson T.; Dickerson, Russell R.

2013-01-01

Air quality models, such as the Community Multiscale Air Quality (CMAQ) model, indicate decidedly higher ozone near the surface of large interior water bodies, such as the Great Lakes and Chesapeake Bay. In order to test the validity of the model output, we performed surface measurements of ozone (O3) and total reactive nitrogen (NOy) on the 26-m Delaware II NOAA Small Research Vessel experimental (SRVx), deployed in the Chesapeake Bay for 10 daytime cruises in July 2011 as part of NASA's GEO-CAPE CBODAQ oceanographic field campaign in conjunction with NASA's DISCOVER-AQ air quality field campaign. During this 10-day period, the EPA O3 regulatory standard of 75 ppbv averaged over an 8-h period was exceeded four times over water while ground stations in the area only exceeded the standard at most twice. This suggests that on days when the Baltimore/Washington region is in compliance with the EPA standard, air quality over the Chesapeake Bay might exceed the EPA standard. Ozone observations over the bay during the afternoon were consistently 10-20% higher than the closest upwind ground sites during the 10-day campaign; this pattern persisted during good and poor air quality days. A lower boundary layer, reduced cloud cover, slower dry deposition rates, and other lesser mechanisms, contribute to the local maximum of ozone over the Chesapeake Bay. Observations from this campaign were compared to a CMAQ simulation at 1.33 km resolution. The model is able to predict the regional maximum of ozone over the Chesapeake Bay accurately, but NOy concentrations are significantly overestimated. Explanations for the overestimation of NOy in the model simulations are also explored

Higher surface ozone concentrations over the Chesapeake Bay than over the adjacent land: Observations and models from the DISCOVER-AQ and CBODAQ campaigns

NASA Astrophysics Data System (ADS)

Goldberg, Daniel L.; Loughner, Christopher P.; Tzortziou, Maria; Stehr, Jeffrey W.; Pickering, Kenneth E.; Marufu, Lackson T.; Dickerson, Russell R.

2014-02-01

Air quality models, such as the Community Multiscale Air Quality (CMAQ) model, indicate decidedly higher ozone near the surface of large interior water bodies, such as the Great Lakes and Chesapeake Bay. In order to test the validity of the model output, we performed surface measurements of ozone (O3) and total reactive nitrogen (NOy) on the 26-m Delaware II NOAA Small Research Vessel experimental (SRVx), deployed in the Chesapeake Bay for 10 daytime cruises in July 2011 as part of NASA's GEO-CAPE CBODAQ oceanographic field campaign in conjunction with NASA's DISCOVER-AQ air quality field campaign. During this 10-day period, the EPA O3 regulatory standard of 75 ppbv averaged over an 8-h period was exceeded four times over water while ground stations in the area only exceeded the standard at most twice. This suggests that on days when the Baltimore/Washington region is in compliance with the EPA standard, air quality over the Chesapeake Bay might exceed the EPA standard. Ozone observations over the bay during the afternoon were consistently 10-20% higher than the closest upwind ground sites during the 10-day campaign; this pattern persisted during good and poor air quality days. A lower boundary layer, reduced cloud cover, slower dry deposition rates, and other lesser mechanisms, contribute to the local maximum of ozone over the Chesapeake Bay. Observations from this campaign were compared to a CMAQ simulation at 1.33 km resolution. The model is able to predict the regional maximum of ozone over the Chesapeake Bay accurately, but NOy concentrations are significantly overestimated. Explanations for the overestimation of NOy in the model simulations are also explored.

Air Quality uFIND: User-oriented Tool Set for Air Quality Data Discovery and Access

NASA Astrophysics Data System (ADS)

Hoijarvi, K.; Robinson, E. M.; Husar, R. B.; Falke, S. R.; Schultz, M. G.; Keating, T. J.

2012-12-01

Historically, there have been major impediments to seamless and effective data usage encountered by both data providers and users. Over the last five years, the international Air Quality (AQ) Community has worked through forums such as the Group on Earth Observations AQ Community of Practice, the ESIP AQ Working Group, and the Task Force on Hemispheric Transport of Air Pollution to converge on data format standards (e.g., netCDF), data access standards (e.g., Open Geospatial Consortium Web Coverage Services), metadata standards (e.g., ISO 19115), as well as other conventions (e.g., CF Naming Convention) in order to build an Air Quality Data Network. The centerpiece of the AQ Data Network is the web service-based tool set: user-oriented Filtering and Identification of Networked Data. The purpose of uFIND is to provide rich and powerful facilities for the user to: a) discover and choose a desired dataset by navigation through the multi-dimensional metadata space using faceted search, b) seamlessly access and browse datasets, and c) use uFINDs facilities as a web service for mashups with other AQ applications and portals. In a user-centric information system such as uFIND, the user experience is improved by metadata that includes the general fields for discovery as well as community-specific metadata to narrow the search beyond space, time and generic keyword searches. However, even with the community-specific additions, the ISO 19115 records were formed in compliance with the standard, so that other standards-based search interface could leverage this additional information. To identify the fields necessary for metadata discovery we started with the ISO 19115 Core Metadata fields and fields that were needed for a Catalog Service for the Web (CSW) Record. This fulfilled two goals - one to create valid ISO 19115 records and the other to be able to retrieve the records through a Catalog Service for the Web query. Beyond the required set of fields, the AQ Community added

Sharing Lessons-Learned on Effective Open Data, Open-Source Practices from OpenAQ, a Global Open Air Quality Community.

NASA Astrophysics Data System (ADS)

Hasenkopf, C. A.

2017-12-01

Increasingly, open data, open-source projects are unearthing rich datasets and tools, previously impossible for more traditional avenues to generate. These projects are possible, in part, because of the emergence of online collaborative and code-sharing tools, decreasing costs of cloud-based services to fetch, store, and serve data, and increasing interest of individuals to contribute their time and skills to 'open projects.' While such projects have generated palpable enthusiasm from many sectors, many of these projects face uncharted paths for sustainability, visibility, and acceptance. Our project, OpenAQ, is an example of an open-source, open data community that is currently forging its own uncharted path. OpenAQ is an open air quality data platform that aggregates and universally formats government and research-grade air quality data from 50 countries across the world. To date, we make available more than 76 million air quality (PM2.5, PM10, SO2, NO2, O3, CO and black carbon) data points through an open Application Programming Interface (API) and a user-customizable download interface at https://openaq.org. The goal of the platform is to enable an ecosystem of users to advance air pollution efforts from science to policy to the private sector. The platform is also an open-source project (https://github.com/openaq) and has only been made possible through the coding and data contributions of individuals around the world. In our first two years of existence, we have seen requests for data to our API skyrocket to more than 6 million datapoints per month, and use-cases as varied as ingesting data aggregated from our system into real-time models of wildfires to building open-source statistical packages (e.g. ropenaq and py-openaq) on top of the platform to creating public-friendly apps and chatbots. We will share a whirl-wind trip through our evolution and the many lessons learned so far related to platform structure, community engagement, organizational model type

Relationship Between Column-Density and Surface Mixing Ratio: Statistical Analysis of O3 and NO2 Data from the July 2011 Maryland DISCOVER-AQ Mission

NASA Technical Reports Server (NTRS)

Flynn, Clare; Pickering, Kenneth E.; Crawford, James H.; Lamsol, Lok; Krotkov, Nickolay; Herman, Jay; Weinheimer, Andrew; Chen, Gao; Liu, Xiong; Szykman, James;

Towards an operational high-resolution air quality forecasting system at ECCC

NASA Astrophysics Data System (ADS)

Munoz-Alpizar, Rodrigo; Stroud, Craig; Ren, Shuzhan; Belair, Stephane; Leroyer, Sylvie; Souvanlasy, Vanh; Spacek, Lubos; Pavlovic, Radenko; Davignon, Didier; Moran, Moran

2017-04-01

Urban environments are particularly sensitive to weather, air quality (AQ), and climatic conditions. Despite the efforts made in Canada to reduce pollution in urban areas, AQ continues to be a concern for the population, especially during short-term episodes that could lead to exceedances of daily air quality standards. Furthermore, urban air pollution has long been associated with significant adverse health effects. In Canada, the large percentage of the population living in urban areas ( 81%, according to the Canada's 2011 census) is exposed to elevated air pollution due to local emissions sources. Thus, in order to improve the services offered to the Canadian public, Environment and Climate Change Canada has launched an initiative to develop a high-resolution air quality prediction capacity for urban areas in Canada. This presentation will show observed pollution trends (2010-2016) for Canadian mega-cities along with some preliminary high-resolution air quality modelling results. Short-term and long-term plans for urban AQ forecasting in Canada will also be described.

Assessment of Emerging Regional Air Quality (AQ) and Greenhouse Gas (GHG) Impacts and Potential Mitigation Strategies in U.S. Energy Sectors

NASA Astrophysics Data System (ADS)

Kinnon, Michael Mac

The current domestic reliance on high-emitting fossil fuels for energy needs is the key driver of U.S. greenhouse gas (GHG) and pollutant emissions driving both climate change and regional air quality (AQ) concerns. Moving forward, emission sources in U.S. energy sectors will be subjected to changes driven by numerous phenomena, including technology evolution, environmental impacts, sustainability goals, and socioeconomic factors. This evolution will directly affect emissions source-related impacts on regional AQ that effective emissions control strategies must account for, including relative source contributions. Though previous studies have evaluated the emissions and AQ impacts of different sectors, technologies and fuels, most previous studies have assessed emissions impacts only without using advanced atmospheric models to accurately account for both spatial and temporal emissions perturbations and atmospheric chemistry and transport. In addition, few previous studies have considered the integration of multiple technologies and fuels in different U.S. regions.. Finally, most studies do not project emissions several decades into the future to assess what sources should be targeted with priority over time. These aspects are critical for understanding how both emissions sources and potential mitigation strategies impact the formation and fate of primary and secondary pollutants, including ground-level ozone and particulate matter concentrations. Therefore, this work utilizes a set of modeling tools to project and then to spatially and temporally resolve emissions as input into a 3-D Eulerian AQ model to assess how sources of emissions contribute to future atmospheric pollutant burdens. Further, analyses of the potential impacts of alternative energy strategies contained in potential mitigation strategies are conducted for priority targets to develop an understanding of how to maximize AQ benefits and avoid unforeseen deleterious tradeoffs between GHG reduction

Trace Gas Retrievals from the GeoTASO Aircraft Instrument During the DISCOVER-AQ Campaigns

NASA Astrophysics Data System (ADS)

Nowlan, C. R.; Liu, X.; Leitch, J. W.; Liu, C.; Gonzalez Abad, G.; Chance, K.; Delker, T.; Good, W. S.; Murcray, F.; Ruppert, L.; Kaptchen, P. F.; Loughner, C.; Follette-Cook, M. B.; Pickering, K. E.

2014-12-01

The Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) instrument is a recently-developed passive remote sensing instrument capable of making 2-D measurements of trace gases from aircraft. GeoTASO was developed under NASA's Instrument Incubator program and is a test-bed instrument for the Geostationary Coastal and Air Pollution Events (GEO-CAPE) decadal survey and the upcoming Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite missions. The instrument collects spectra of backscattered UV-visible radiation for the detection of tropospheric trace gases such as NO2, ozone, formaldehyde and SO2. GeoTASO flew on the NASA HU-25C Falcon aircraft during the 2013 (Texas) and 2014 (Colorado) DISCOVER-AQ field campaigns, making satellite-analog measurements of trace gases at a spatial resolution of approximately 500x500 m over urban areas, power plants and other industrial sources of pollution. We present the GeoTASO retrieval algorithms, trace gas measurement results, and validation comparisons with ground-based observations and other aircraft instruments during these campaigns.

76 FR 72097 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-22

... broad range of adverse health effects. These may include damage to the central nervous system...) Meteorology (weather/transport patterns); (6) Geography/topography (mountain ranges or other air basin... to the EPA's Air Quality System (AQS), or otherwise available to the EPA, and meeting the...

Ozone production and its sensitivity to NOx and VOCs: results from the DISCOVER-AQ field experiment, Houston 2013

NASA Astrophysics Data System (ADS)

Mazzuca, Gina M.; Ren, Xinrong; Loughner, Christopher P.; Estes, Mark; Crawford, James H.; Pickering, Kenneth E.; Weinheimer, Andrew J.; Dickerson, Russell R.

2016-11-01

An observation-constrained box model based on the Carbon Bond mechanism, version 5 (CB05), was used to study photochemical processes along the NASA P-3B flight track and spirals over eight surface sites during the September 2013 Houston, Texas deployment of the NASA Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaign. Data from this campaign provided an opportunity to examine and improve our understanding of atmospheric photochemical oxidation processes related to the formation of secondary air pollutants such as ozone (O3). O3 production and its sensitivity to NOx and volatile organic compounds (VOCs) were calculated at different locations and times of day. Ozone production efficiency (OPE), defined as the ratio of the ozone production rate to the NOx oxidation rate, was calculated using the observations and the simulation results of the box and Community Multiscale Air Quality (CMAQ) models. Correlations of these results with other parameters, such as radical sources and NOx mixing ratio, were also evaluated. It was generally found that O3 production tends to be more VOC-sensitive in the morning along with high ozone production rates, suggesting that control of VOCs may be an effective way to control O3 in Houston. In the afternoon, O3 production was found to be mainly NOx-sensitive with some exceptions. O3 production near major emissions sources such as Deer Park was mostly VOC-sensitive for the entire day, other urban areas near Moody Tower and Channelview were VOC-sensitive or in the transition regime, and areas farther from downtown Houston such as Smith Point and Conroe were mostly NOx-sensitive for the entire day. It was also found that the control of NOx emissions has reduced O3 concentrations over Houston but has led to larger OPE values. The results from this work strengthen our understanding of O3 production; they indicate that controlling NOx emissions will provide

Performance assessment of retrospective meteorological inputs for use in air quality modeling during TexAQS 2006

NASA Astrophysics Data System (ADS)

Ngan, Fong; Byun, Daewon; Kim, Hyuncheol; Lee, Daegyun; Rappenglück, Bernhard; Pour-Biazar, Arastoo

2012-07-01

To achieve more accurate meteorological inputs than was used in the daily forecast for studying the TexAQS 2006 air quality, retrospective simulations were conducted using objective analysis and 3D/surface analysis nudging with surface and upper observations. Model ozone using the assimilated meteorological fields with improved wind fields shows better agreement with the observation compared to the forecasting results. In the post-frontal conditions, important factors for ozone modeling in terms of wind patterns are the weak easterlies in the morning for bringing in industrial emissions to the city and the subsequent clockwise turning of the wind direction induced by the Coriolis force superimposing the sea breeze, which keeps pollutants in the urban area. Objective analysis and nudging employed in the retrospective simulation minimize the wind bias but are not able to compensate for the general flow pattern biases inherited from large scale inputs. By using an alternative analyses data for initializing the meteorological simulation, the model can re-produce the flow pattern and generate the ozone peak location closer to the reality. The inaccurate simulation of precipitation and cloudiness cause over-prediction of ozone occasionally. Since there are limitations in the meteorological model to simulate precipitation and cloudiness in the fine scale domain (less than 4-km grid), the satellite-based cloud is an alternative way to provide necessary inputs for the retrospective study of air quality.

High Spectral Resolution LIDAR as a Tool for Air Quality Research

NASA Astrophysics Data System (ADS)

Eloranta, E. W.; Spuler, S.; Hayman, M. M.

2017-12-01

Many aspects of air quality research require information on the vertical distribution of pollution. Traditional measurements, obtained from surface based samplers, or passive satellite remote sensing, do not provide vertical profiles. Lidar can provide profiles of aerosol properties. However traditional backscatter lidar suffers from uncertain calibrations with poorly constrained algorithms. These problems are avoided using High Spectral Resolution Lidar (HSRL) which provides absolutely calibrated vertical profiles of aerosol properties. The University of Wisconsin HSRL systems measure 532 nm wavelength aerosol backscatter cross-sections, extinction cross-sections, depolarization, and attenuated 1064 nm backscatter. These instruments are designed for long-term deployment at remote sites with minimal local support. Processed data is provided for public viewing and download in real-time on our web site "http://hsrl.ssec.wisc.edu". Air pollution applications of HSRL data will be illustrated with examples acquired during air quality field programs including; KORUS-AQ, DISCOVER-AQ, LAMOS and FRAPPE. Observations include 1) long range transport of dust, air pollution and smoke. 2) Fumigation episodes where elevated pollution is mixed down to the surface. 3) visibility restrictions by aerosols and 4) diurnal variations in atmospheric optical depth. While HSRL is powerful air quality research tool, its application in routine measurement networks is hindered by the high cost of current systems. Recent technical advances promise a next generation HSRL using telcom components to greatly reduce system cost. This paper will present data generated by a prototype low cost system constructed at NCAR. In addition to lower cost, operation at a non-visible near 780 nm infrared wavelength removes all FAA restrictions on the operation.

Ozone Production and Its Sensitivity to NOx and VOCs: Results from the DISCOVER-AQ Field Experiment, Houston 2013

NASA Astrophysics Data System (ADS)

Ren, X.; Mazzuca, G.; Loughner, C.; Estes, M. J.; Crawford, J. H.; Weinheimer, A. J.; Pickering, K. E.; Dickerson, R. R.

2016-12-01

An observation-constrained box model based on the Carbon Bond mechanism, Version 5 (CB05), was used to study photochemical processes along the NASA P-3B flight track and spirals over eight surface sites during the September 2013 Houston, Texas deployment of the NASA DISCOVER-AQ campaign. Data from this campaign provided an opportunity to examine and improve our understanding of atmospheric photochemical oxidation processes related to the formation of secondary air pollutants such as ozone (O3). O3 production and its sensitivity to NOx and VOCs were calculated at different locations and times of day. Ozone production efficiency (OPE), defined as the ratio of the ozone production rate to the NOx oxidation rate, was calculated using the observations and the simulation results of the box and Community Multiscale Air Quality (CMAQ) models. Correlation of these results with other parameters, such as radical sources and NOx mixing ratio, was also evaluated. It was generally found that O3 production tends to be more VOC sensitive in the morning along with high ozone production rates, suggesting that control of VOCs may be an effective way to control O3 in Houston. In the afternoon, O3 production was found to be mainly NOx sensitive with some exceptions. O3 production at near major emissions sources such as Deer Park was mostly VOC sensitive for the entire day, other urban areas near Moody Tower and Channelview were VOC sensitive or in the transition regime, and areas farther from downtown Houston such as Smith Point and Conroe were mostly NOx sensitive for the entire day. It was also found that the control of NOx emissions has reduced O3 concentrations over Houston, but led to larger OPE values. The results from this work strengthen our understanding of O3 production; they indicate that controlling NOx emissions will provide air quality benefits over the greater Houston metropolitan area in the long run, but in selected areas controlling VOC emissions will also be

The Application of a Novel Pressurized Liquid Extraction Method to Quantify Organic Tracers Combined with Historic and Novel Organic Contaminants for the Discover-AQ Houston Field Experiment

NASA Astrophysics Data System (ADS)

Clark, A. E.; Yoon, S.; Sheesley, R. J.; Usenko, S.

2014-12-01

DISCOVER-AQ is a NASA mission seeking to better understand air quality in cities across the United States. In September 2013, flight, satellite and ground-based data was collected in Houston, TX and the surrounding metropolitan area. Over 300 particulate matter filter samples were collected as part of the ground-based sampling efforts, at four sites across Houston. Samples include total suspended particle matter (TSP) and fine particulate matter (less than 2.5 μm in aerodynamic diameter; PM2.5). For this project, an analytical method has been developed for the pressurized liquid extraction (PLE) of a wide variety of organic tracers and contaminants from quartz fiber filters (QFFs). Over 100 compounds were selected including polycyclic aromatic hydrocarbons (PAHs), hopanes, levoglucosan, organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organophosphate flame retardants (OPFRs). Currently, there is no analytical method validated for the reproducible extraction of all seven compound classes in a single automated technique. Prior to extraction, QFF samples were spiked with known amounts of target analyte standards and isotopically-labeled surrogate standards. The QFF were then extracted with methylene chloride:acetone at high temperatures (100˚C) and pressures (1500 psi) using a Thermo Dionex Accelerated Solvent Extractor system (ASE 350). Extracts were concentrated, spiked with known amounts of isotopically-labeled internal standards, and analyzed by gas chromatography coupled with mass spectrometry utilizing electron ionization and electron capture negative ionization. Target analytes were surrogate recovery-corrected to account for analyte loss during sample preparation. Ambient concentrations of over 100 organic tracers and contaminants will be presented for four sites in Houston during DISCOVER-AQ.

DISCOVER-AQ Airborne Measurements Quantify How Satellite-Retrievable Becomes Health-Relevant: The Example Of Smog And Its Production

NASA Astrophysics Data System (ADS)

Esswein, R. F.; Chatfield, R. B.; Crawford, J. H.; Weinheimer, A. J.; Fried, A.; Barrick, J. D.

2012-12-01

Unusually rich information about health-relevant surface smog pollution may be expected from developing multi-wavelength retrievals from space, e.g., in upcoming missions being planned by the United States ("GEO-CAPE") and by European and Asian agencies. The key is that ozone and its precursors are vertically correlated in layers that can be retrieved, and that situation-to-situation variation is more important than small local spatial variations. Variations in relationships are understood in terms of simple weather principles such as subsidence and repeating local circulation features. BACKGROUND: Near-surface pollution is one of the most challenging problems for Earth observations from space. Near- surface information must be inferred from column-integrated quantities obtained by passive remote sensing from nadir-looking satellite instruments. NASA has undertaken a major five-year experimental mission to investigate air pollution on the 1- to 100-km urban/regional scale. The mission concept involved Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality, generally known better by its acronym DISCOVER-AQ. A major goal is to understand the usefulness of and best methodologies for satellite remote sensing data. The DISCOVER-AQ airborne study repeatedly made spirals over various urban, industrial, transportation, and rural sites in detail around the Baltimore-Washington area in July, 2011. We compare mixing ratios appropriately averaged over a 0.2-3 km altitude ("Retrievable") and those measured at the bottom of the spirals, 0.2-0.5 km, the "Relevant". The "Retrievable" layer 0.2-3 km. was set by GEO-CAPE remote- sensing sensitivity analyses for ozone [Natraj et al., Atmos. Environ., 2011]. Correlations were quite good, ca. 0.9. Retrieved-relevant correlations for O3 were determined mostly by synoptic conditions. Comparisons for NO2 and HCHO mixing ratio (= m.r.) and especially log(m.r.) are affected by

76 FR 6056 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-03

...-9261-3] RIN 2060-AQ30 Additional Air Quality Designations for the 2006 24-Hour Fine Particle National..., and Decisions Related to the 1997 Air Quality Designations and Classifications for the Annual Fine... nationwide for all but three areas for the 2006 24-hour fine particle (PM 2.5 ) National Ambient Air Quality...

Nitrogen dioxide observations from the Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) airborne instrument: Retrieval algorithm and measurements during DISCOVER-AQ Texas 2013

NASA Astrophysics Data System (ADS)

Nowlan, Caroline R.; Liu, Xiong; Leitch, James W.; Chance, Kelly; González Abad, Gonzalo; Liu, Cheng; Zoogman, Peter; Cole, Joshua; Delker, Thomas; Good, William; Murcray, Frank; Ruppert, Lyle; Soo, Daniel; Follette-Cook, Melanie B.; Janz, Scott J.; Kowalewski, Matthew G.; Loughner, Christopher P.; Pickering, Kenneth E.; Herman, Jay R.; Beaver, Melinda R.; Long, Russell W.; Szykman, James J.; Judd, Laura M.; Kelley, Paul; Luke, Winston T.; Ren, Xinrong; Al-Saadi, Jassim A.

2016-06-01

The Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) airborne instrument is a test bed for upcoming air quality satellite instruments that will measure backscattered ultraviolet, visible and near-infrared light from geostationary orbit. GeoTASO flew on the NASA Falcon aircraft in its first intensive field measurement campaign during the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) Earth Venture Mission over Houston, Texas, in September 2013. Measurements of backscattered solar radiation between 420 and 465 nm collected on 4 days during the campaign are used to determine slant column amounts of NO2 at 250 m × 250 m spatial resolution with a fitting precision of 2.2 × 1015 moleculescm-2. These slant columns are converted to tropospheric NO2 vertical columns using a radiative transfer model and trace gas profiles from the Community Multiscale Air Quality (CMAQ) model. Total column NO2 from GeoTASO is well correlated with ground-based Pandora observations (r = 0.90 on the most polluted and cloud-free day of measurements and r = 0.74 overall), with GeoTASO NO2 slightly higher for the most polluted observations. Surface NO2 mixing ratios inferred from GeoTASO using the CMAQ model show good correlation with NO2 measured in situ at the surface during the campaign (r = 0.85). NO2 slant columns from GeoTASO also agree well with preliminary retrievals from the GEO-CAPE Airborne Simulator (GCAS) which flew on the NASA King Air B200 (r = 0.81, slope = 0.91). Enhanced NO2 is resolvable over areas of traffic NOx emissions and near individual petrochemical facilities.

Nitrogen Dioxide Observations from the Geostationary Trace Gas and Aerosol Sensor Optimization (GeoTaso) Airborne Instrument: Retrieval Algorithm and Measurements During DISCOVER-AQ Texas 2013

NASA Technical Reports Server (NTRS)

Nowlan, Caroline R.; Liu, Xiong; Leitch, James W.; Chance, Kelly; Abad, Gonzalo Gonzalez; Liu, Xiaojun; Zoogman, Peter; Cole, Joshua; Delker, Thomas; Good, William;

Ozone Profiles in the Baltimore-Washington Region (2006-2011): Satellite Comparisons and DISCOVER-AQ Observations

NASA Technical Reports Server (NTRS)

Thompson, Anne M.; Stauffer, Ryan M.; Miller, Sonya K.; Martins, Douglas K.; Joseph, Everette; Weinheimer, Andrew J.; Diskin, Glenn S.

2014-01-01

Much progress has been made in creating satellite products for tracking the pollutants ozone and NO2 in the troposphere. Yet, in mid-latitude regions where meteorological interactions with pollutants are complex, accuracy can be difficult to achieve, largely due to persistent layering of some constituents. We characterize the layering of ozone soundings and related species measured from aircraft over two ground sites in suburban Washington, DC (Beltsville, MD, 39.05N; 76.9W) and Baltimore (Edgewood, MD, 39.4N; 76.3W) during the July 2011 DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) experiment. First, we compare column-ozone amounts from the Beltsville and Edgewood sondes with data from overpassing satellites. Second, processes influencing ozone profile structure are analyzed using Laminar Identification and tracers: sonde water vapor, aircraft CO and NOy. Third, Beltsville ozone profiles and meteorological influences in July 2011 are compared to those from the summers of 2006-2010. Sonde-satellite offsets in total ozone during July 2011 at Edgewood and Beltsville, compared to the Ozone Monitoring Instrument (OMI), were 3 percent mean absolute error, not statistically significant. The disagreement between an OMIMicrowave Limb Sounder-based tropospheric ozone column and the sonde averaged 10 percent at both sites, with the sonde usually greater than the satellite. Laminar Identification (LID), that distinguishes ozone segments influenced by convective and advective transport, reveals that on days when both stations launched ozonesondes, vertical mixing was stronger at Edgewood. Approximately half the lower free troposphere sonde profiles have very dry laminae, with coincident aircraft spirals displaying low CO (80-110 ppbv), suggesting stratospheric influence. Ozone budgets at Beltsville in July 2011, determined with LID, as well as standard meteorological indicators, resemble those

Overview of Ground Air Quality Measurements and Their Links to Airborne, Remote Sensing and Model Studies during the KORUS-AQ Campaign

NASA Astrophysics Data System (ADS)

Lee, G.; Ahn, J. Y.; Chang, L. S.; Kim, J.; Park, R.

2017-12-01

During the KORUS-AQ, extensive sets of chemical measurements for reactive gases and aerosol species were made at 3 major sites on upwind island (Baengyeong Island), urban (Olympic Park in Seoul) and downwind rural forest location (Taewha Forest). Also, intensive aerosol size and composition observations from 5 NIER super sites, 3 NIMR monitoring sites, and 5 other university sites were currently facilitated in the KORUS-AQ data set. In addition, air quality criteria species data from 264 nation-wide ground monitoring sites with 5 minute temporal resolution during the whole campaign period were supplemented to cover mostly in densely populated urban areas, but sparsely in rural areas. The specific objectives of these ground sites were to provide highly comprehensive data set to coordinate the close collaborations among other research platforms including airborne measurements, remote sensing, and model studies. The continuous measurements at ground sites were well compared with repetitive low-level aircraft observations of NASA's DC-8 over Olympic Park and Taewha Forest site. Similarly, many ground measurements enabled the validation of chemical transport models and the remote sensing observations from ground and NASA's King Air. The observed results from inter-comparison studies in many reactive gases and aerosol compositions between different measurement methods and platforms will be presented. Compiling data sets from ground sites, source-wise analysis for ozone and aerosol, their in-situ formations, and transport characteristics by local/regional circulation will be discussed, too.

Generating Aerosol Data Products from Airborne in-situ Observations made during 2011 DISCOVER-AQ Field Campaign

NASA Astrophysics Data System (ADS)

Thornhill, K. L.; Anderson, B. E.; Winstead, E. L.; Chen, G.; Beyersdorf, A. J.; Ziemba, L. D.

2011-12-01

In July 2011, the first of four DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) planned field campaigns was completed. The investigation is a broad collaboration between federal and state agencies and academic institutions with the primary goal of improving the interpretation of satellite observations of surface-level trace gas and aerosol parameters by making detailed correlative measurements from aircraft and ground-based instruments in urban regions plagued by air-quality issues. Phase I studied the air-quality of the lower troposphere in and around the Washington, D.C. and Baltimore areas along the I-95 corridor. In-situ airborne data is essential in providing a link between the broad swath satellite measurements and the measurements made by ground based sensors. This is accomplished by examining the relationship between column-integrated values obtained through in-situ sampling and surface measured values, as aircraft can fully characterize atmospheric chemical/aerosol constituents at a given time and location. To that end, the NASA P-3B was instrumented to record fast-response measurements of various gas-phase tracers and aerosol characteristics of pollution. A flight pattern was created and executed for each of the 14 research flights that had the P-3B performing a series of spiral ascents/descents over six ground sites to perform detailed vertical characterizations of the chemical and aerosol structure. The in-situ aerosol characterization was performed by the NASA Langley Aerosol Research Group Experiment (LARGE) using 15 instruments to measure aerosol microphysical, chemical and optical properties. In this presentation we discuss the process in which aerosol science data is generated, from the collection of more than 10 GB of data per 8 hour flight, to the initial QA/QC required to produce a preliminary data product within 24 hours of landing, through final data submission

Satellite Observations of Trace Gases and Their Application for Studying Air Quality Near Oil and Gas Operations

NASA Astrophysics Data System (ADS)

Kollonige, D. E.; Thompson, A. M.; Nichols, M.; Fasnacht, Z.; Martins, D. K.; Dickerson, R. R.

2014-12-01

The increase in the natural gas component of the energy sector has led many state and local municipalities to begin regulation of emissions from the oil and natural gas operators with air quality (AQ) as a concern. "Top-down" measurements of trace gases in the air above wells complement "bottom-up" inventories, used by EPA and AQ stakeholders, through a more accurate depiction of regional variability of methane and other species near and downwind of oil and gas operations. Satellite observations of methane, nitrogen dioxide, formaldehyde, ozone, and other carbon gases enhance the spatial and temporal coverage of the data needed to demonstrate any long-term impacts from shale gas development. As part of a NASA AQAST (Air Quality Applied Sciences Team) project, we are evaluating satellite measurements of trace gases in regions with oil and gas operations for their application as a "top-down" constraint. For validation of the satellite instruments' sensitivities to emitted gases, we focus on regions where the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) campaign deployed with ground and aircraft measurements, including, Maryland (2011), California and Texas (2013), and Colorado (2014). We compare vertical distributions of methane and volatile organic compounds (VOCs) nearby and downwind of oil and gas wells to locate any regional differences during the campaign time periods. This allows for better characterization of the satellite observations and their limitations for application in air quality studies in similar environments. Taking advantage of current EOS-era satellites' data records, we also analyze methane anomalies and gas correlations in the free troposphere from 2005 to present to identify trends for basins with oil and gas extraction sites and their influence on background concentrations downwind of wells. In most regions with oil and gas activity, we see continually

Postprocessing for Air Quality Predictions

NASA Astrophysics Data System (ADS)

Delle Monache, L.

2017-12-01

In recent year, air quality (AQ) forecasting has made significant progress towards better predictions with the goal of protecting the public from harmful pollutants. This progress is the results of improvements in weather and chemical transport models, their coupling, and more accurate emission inventories (e.g., with the development of new algorithms to account in near real-time for fires). Nevertheless, AQ predictions are still affected at times by significant biases which stem from limitations in both weather and chemistry transport models. Those are the result of numerical approximations and the poor representation (and understanding) of important physical and chemical process. Moreover, although the quality of emission inventories has been significantly improved, they are still one of the main sources of uncertainties in AQ predictions. For operational real-time AQ forecasting, a significant portion of these biases can be reduced with the implementation of postprocessing methods. We will review some of the techniques that have been proposed to reduce both systematic and random errors of AQ predictions, and improve the correlation between predictions and observations of ground-level ozone and surface particulate matter less than 2.5 µm in diameter (PM2.5). These methods, which can be applied to both deterministic and probabilistic predictions, include simple bias-correction techniques, corrections inspired by the Kalman filter, regression methods, and the more recently developed analog-based algorithms. These approaches will be compared and contrasted, and strength and weaknesses of each will be discussed.

76 FR 14812 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-18

... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 81 [EPA-HQ-OAR-2007-0562; EPA-HQ-OAR-2010-0163; FRL-9261-3] RIN-2060-AQ30 Additional Air Quality Designations for the 2006 24-Hour Fine Particle National... Particles National Ambient Air Quality Standards Correction In rule document 2011-2269 appearing on pages...

Field test of a new instrument to measure UV/Vis (300-700 nm) ambient aerosol extinction spectra in Colorado during DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Jordan, C. E.; Anderson, B. E.; Beyersdorf, A. J.; Dibb, J. E.; Greenslade, M. E.; Martin, R.; Scheuer, E. M.; Shook, M.; Thornhill, K. L., II; Troop, D.; Winstead, E.; Ziemba, L. D.

2014-12-01

An optical instrument has been developed to investigate aerosol extinction spectra in the ambient atmosphere. Based on a White-type cell design and using a differential optical approach, aerosol extinction spectra over the 300-700 nm ultraviolet and visible (UV/Vis) wavelength range are obtained. Laboratory tests conducted at NASA Langley Research Center (NASA LaRC) in March 2014 showed good agreement with Cavity Attenuated Phase Shift (CAPS PMex, Aerodyne Research) extinction measurements (at 450, 530, and 630 nm) for a variety of aerosols, e.g., scatterers such as polystyrene latex spheres and ammonium sulfate; absorbers such as dust (including pigmented minerals), smoke (generated in a miniCAST burning propane) and laboratory smoke analogs (e.g., fullerene soot and aquadag). The instrument was field tested in Colorado in July and August 2014 aboard the NASA mobile laboratory at various ground sites during the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. A description of the instrument, results from the laboratory tests, and summer field data will be presented. The instrument provides a new tool for probing in situ aerosol optical properties that may help inform remote sensing approaches well into the UV range.

Maps Suggest Transport and Source Processes of PM2.5 at 1 km x 1 km for the Whole San Joaquin Valley, Winter 2011 (Generalizations from DISCOVER-AQ)

NASA Astrophysics Data System (ADS)

Chatfield, R. B.

2016-12-01

extend these insights to similar regions, e.g. interior valleys of California, the Po Valley, the Mediterranean litoral, and the Ganges Plain. This work show generalizable use of remote sensing, a major goal of DISCOVER-AQ, Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality.

Air Twitter: Mashing Crowdsourced Air Quality Event Identification with Scientific Earth Observations (Invited)

NASA Astrophysics Data System (ADS)

Robinson, E. M.

2010-12-01

The ability to easily expose content through the web using social media sites like YouTube, Flickr, Blogger and Delicious have given the Earth a “skin” of photos, videos and citizen reporting that enhance our understanding ofour surroundings. Businesses are taking advantage of this constant stream of information by “listening” to the social-media chatter on the web. Social listening allows businesses to better identify their customers and provide tailored service to that group. News agencies are also using social listening techniques and have implemented sites like iReport, since it is more and more likely that citizen reporters will ‘break’ news stories and identify major events. Scientist can benefit from social listening as well. Community remote sensing can incorporate the new and evolving social media ‘sensors’ along with remotely sensed surface and satellite data to provide another dimension of contextual understanding about what is occurring in the natural environment. Air Quality (AQ) events such as fires and dust storms are highly visible and impact daily life, thus the pictures, videos, blogs and tweets are shared through web within minutes of the event occurring. Air Twitter is a social media listening tool that aggregates user generated content from around the web that are described using terms like air quality, fire and smoke. Air twitter then filters content further for outdoor air quality and then binds to the content by tagging the filtered stream with #AirQuality. This stream is retweeted through a separate twitter account for the ESIP Air Quality WG (@ESIPAQWG). A unique and unexpected outcome of this is that it has allowed a community of over 1250+ people to follow this stream. Followers include Gov. Schwarzenegger and Boris Johnson, the mayor of London, as well as many local communities AQ agencies that publish their real-time surface monitoring data through Twitter. The aggregated Air Twitter stream is also saved in a database

Hygroscopic Measurements of Aerosol Particles in Colorado during the Discover AQ Campaign 2014

NASA Astrophysics Data System (ADS)

Orozco, D.; Delgado, R.; Espinosa, R.; Martins, J. V.; Hoff, R. M.

2014-12-01

In ambient conditions, aerosol particles experience hygroscopic growth due to the influence of relative humidity (RH), scattering more light than when the particles are dry. The quantitative knowledge of the RH effect and its influence on the light scattering and, in particular, on the phase function and polarization of aerosol particles is of substantial importance when comparing ground observations with other optical aerosol measurements such satellite and sunphotometric retrievals of aerosol optical depth and their inversions. In the summer of 2014, the DISCOVER-AQ campaign was held in Colorado, where systematic and concurrent observations of column- integrated surface, and vertically-resolved distributions of aerosols and trace gases relevant to air quality and their evolution during the day were observed. Aerosol optical properties were measured in the UMBC trailer at the city of Golden using a TSI-3563 nephelometer and an in-situ Polarized Imaging Nephelometer (PI-NEPH) designed and built by the LACO group at UMBC. The PI-NEPH measures aerosol phase matrix components in high angular range between 2 and 178 degrees scattering angle at three wavelengths (λ=473, 532 and 671nm). The two measured elements of the phase matrix, intensity (P11) and linear polarization (P12) provide extensive characterization of the scattering properties of the studied aerosol. The scattering coefficient, P11 and P12 were measured under different humidity conditions to obtain the enhancement factor f(RH) and the dependence of P11 and P12 to RH using a humidifier dryer system covering a RH range from 20 to 90%. The ratio between scattering coefficients at high and low humidity in Golden Colorado showed relatively low hygroscopic growth in the aerosol particles f(RH=80%) was 1.27±0.19 for the first three weeks of sampling. According to speciated measurements performed at the UMBC trailer, the predominance of dust and organic aerosols over more hygroscopic nitrate and sulfate in the

Evaluation of Sulfur Dioxide (SO2) Simulations with the GEOS-5/ GOCART Model during the Frostburg/DISCOVER-AQ Field Campaigns

NASA Astrophysics Data System (ADS)

Buchard-Marchant, V.; da Silva, A.; Colarco, P. R.; Krotkov, N. A.; Dickerson, R. R.; Stehr, J. W.; Spinei, E.; Mount, G. H.; Krask, D.

2011-12-01

Sulfur dioxide (SO2) is a major atmospheric pollutant, with a strong anthropogenic component mostly produced by the combustion of fossil fuel and other industrial activities. As a precursor of sulfate aerosols that affect climate, air quality and human health, this gas needs to be monitored on a global scale. Global climate and chemistry models including aerosol processes along with their radiative effects are important tools for climate and air quality research. Validation of these models against in-situ and satellite measurements are essential to ascertain the credibility of these models and to guide model improvements. In this study the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) module running on-line inside the Goddard Earth Observing System version 5 (GEOS-5) model is used to simulate aerosol and SO2 concentrations. The global GEOS-5 system runs at a nominal 25 km horizontal resolution with 72 vertical levels; a comprehensive atmospheric data assimilation system is used to constrain the meteorological state of the model. Data taken over Maryland in the UM's Frostburg (November 2010) and NASA DISCOVER-AQ (July 2011) field campaigns are used to evaluate the GEOS-5 SO2 concentrations. In this presentation we show comparisons of simulated and measured SO2 concentration, using airborne and ground-based data sets, as well as data from the space-based OMI instrument. Preliminary data analysis indicated the model's overestimation of SO2 concentration at the surface, leading to a close examination of mixing processes in the model and the specification of SO2 anthropogenic emission rates. As a result of this analysis, we have implemented a revision of anthropogenic emission inventories in GEOS-5, and updated the vertical placement of SO2 sources. In this presentation we show how these revisions improve the model agreement with observations not only locally but also in regions outside the area of these field campaigns. In particular, we use the ground

Variability of O3 and NO2 profile shapes during DISCOVER-AQ: Implications for satellite observations and comparisons to model-simulated profiles

NASA Astrophysics Data System (ADS)

Flynn, Clare Marie; Pickering, Kenneth E.; Crawford, James H.; Weinheimer, Andrew J.; Diskin, Glenn; Thornhill, K. Lee; Loughner, Christopher; Lee, Pius; Strode, Sarah A.

2016-12-01

To investigate the variability of in situ profile shapes under a variety of meteorological and pollution conditions, results are presented of an agglomerative hierarchical cluster analysis of the in situ O3 and NO2 profiles for each of the four campaigns of the NASA DISCOVER-AQ mission. Understanding the observed profile variability for these trace gases is useful for understanding the accuracy of the assumed profile shapes used in satellite retrieval algorithms as well as for understanding the correlation between satellite column observations and surface concentrations. The four campaigns of the DISCOVER-AQ mission took place in Maryland during July 2011, the San Joaquin Valley of California during January-February 2013, the Houston, Texas, metropolitan region during September 2013, and the Denver-Front Range region of Colorado during July-August 2014. Several distinct profile clusters emerged for the California, Texas, and Colorado campaigns for O3, indicating significant variability of O3 profile shapes, while the Maryland campaign presented only one distinct O3 cluster. In contrast, very few distinct profile clusters emerged for NO2 during any campaign for this particular clustering technique, indicating the NO2 profile behavior was relatively uniform throughout each campaign. However, changes in NO2 profile shape were evident as the boundary layer evolved through the day, but they were apparently not significant enough to yield more clusters. The degree of vertical mixing (as indicated by temperature lapse rate) associated with each cluster exerted an important influence on the shapes of the median cluster profiles for O3, as well as impacted the correlations between the associated column and surface data for each cluster for O3. The correlation analyses suggest satellites may have the best chance to relate to surface O3 under the conditions encountered during the Maryland campaign Clusters 1 and 2, which include deep, convective boundary layers and few

Frequency and Impact of Summertime Stratospheric Intrusions Over Maryland During DISCOVER-AQ (2011): New Evidence from NASA's GEOS-5 Simulations

NASA Technical Reports Server (NTRS)

Ott, Lesley E.; Duncan, Bryan N.; Thompson, Anne M.; Diskin, Glenn; Fasnacht, Zachary; Langford, Andrew O.; Lin, Meiyun; Molod, Andrea Mara; Nielsen, J. Eric; Pusede, Sally E.;

Improving Air Quality (and Weather) Predictions using Advanced Data Assimilation Techniques Applied to Coupled Models during KORUS-AQ

NASA Astrophysics Data System (ADS)

Carmichael, G. R.; Saide, P. E.; Gao, M.; Streets, D. G.; Kim, J.; Woo, J. H.

2017-12-01

Ambient aerosols are important air pollutants with direct impacts on human health and on the Earth's weather and climate systems through their interactions with radiation and clouds. Their role is dependent on their distributions of size, number, phase and composition, which vary significantly in space and time. There remain large uncertainties in simulated aerosol distributions due to uncertainties in emission estimates and in chemical and physical processes associated with their formation and removal. These uncertainties lead to large uncertainties in weather and air quality predictions and in estimates of health and climate change impacts. Despite these uncertainties and challenges, regional-scale coupled chemistry-meteorological models such as WRF-Chem have significant capabilities in predicting aerosol distributions and explaining aerosol-weather interactions. We explore the hypothesis that new advances in on-line, coupled atmospheric chemistry/meteorological models, and new emission inversion and data assimilation techniques applicable to such coupled models, can be applied in innovative ways using current and evolving observation systems to improve predictions of aerosol distributions at regional scales. We investigate the impacts of assimilating AOD from geostationary satellite (GOCI) and surface PM2.5 measurements on predictions of AOD and PM in Korea during KORUS-AQ through a series of experiments. The results suggest assimilating datasets from multiple platforms can improve the predictions of aerosol temporal and spatial distributions.

76 FR 77739 - Approval and Promulgation of Air Quality Implementation Plans; Massachusetts and New Hampshire...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-14

... in EPA's Air Quality System (AQS) database. To account for missing data, the procedures found in... determination is based upon complete, certified, quality-assured ambient air quality monitoring data for the... proposing? II. What is the background for this proposed action? III. What is EPA's analysis of data for...

The Use of Regulatory Air Quality Models to Develop Successful Ozone Attainment Strategies

NASA Astrophysics Data System (ADS)

Canty, T. P.; Salawitch, R. J.; Dickerson, R. R.; Ring, A.; Goldberg, D. L.; He, H.; Anderson, D. C.; Vinciguerra, T.

2015-12-01

The Environmental Protection Agency (EPA) recently proposed lowering the 8-hr ozone standard to between 65-70 ppb. Not all regions of the U.S. are in attainment of the current 75 ppb standard and it is expected that many regions currently in attainment will not meet the future, lower surface ozone standard. Ozone production is a nonlinear function of emissions, biological processes, and weather. Federal and state agencies rely on regulatory air quality models such as the Community Multi-Scale Air Quality (CMAQ) model and Comprehensive Air Quality Model with Extensions (CAMx) to test ozone precursor emission reduction strategies that will bring states into compliance with the National Ambient Air Quality Standards (NAAQS). We will describe various model scenarios that simulate how future limits on emission of ozone precursors (i.e. NOx and VOCs) from sources such as power plants and vehicles will affect air quality. These scenarios are currently being developed by states required to submit a State Implementation Plan to the EPA. Projections from these future case scenarios suggest that strategies intended to control local ozone may also bring upwind states into attainment of the new NAAQS. Ground based, aircraft, and satellite observations are used to ensure that air quality models accurately represent photochemical processes within the troposphere. We will highlight some of the improvements made to the CMAQ and CAMx model framework based on our analysis of NASA observations obtained by the OMI instrument on the Aura satellite and by the DISCOVER-AQ field campaign.

Multi-pollutant surface objective analyses and mapping of air quality health index over North America.

PubMed

Robichaud, Alain; Ménard, Richard; Zaïtseva, Yulia; Anselmo, David

2016-01-01

Air quality, like weather, can affect everyone, but responses differ depending on the sensitivity and health condition of a given individual. To help protect exposed populations, many countries have put in place real-time air quality nowcasting and forecasting capabilities. We present in this paper an optimal combination of air quality measurements and model outputs and show that it leads to significant improvements in the spatial representativeness of air quality. The product is referred to as multi-pollutant surface objective analyses (MPSOAs). Moreover, based on MPSOA, a geographical mapping of the Canadian Air Quality Health Index (AQHI) is also presented which provides users (policy makers, public, air quality forecasters, and epidemiologists) with a more accurate picture of the health risk anytime and anywhere in Canada and the USA. Since pollutants can also behave as passive atmospheric tracers, they provide information about transport and dispersion and, hence, reveal synoptic and regional meteorological phenomena. MPSOA could also be used to build air pollution climatology, compute local and national trends in air quality, and detect systematic biases in numerical air quality (AQ) models. Finally, initializing AQ models at regular time intervals with MPSOA can produce more accurate air quality forecasts. It is for these reasons that the Canadian Meteorological Centre (CMC) in collaboration with the Air Quality Research Division (AQRD) of Environment Canada has recently implemented MPSOA in their daily operations.

“Fine-Scale Application of the coupled WRF-CMAQ System to ...

EPA Pesticide Factsheets

The DISCOVER-AQ project (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality), is a joint collaboration between NASA, U.S. EPA and a number of other local organizations with the goal of characterizing air quality in urban areas using satellite, aircraft, vertical profiler and ground based measurements (http://discover-aq.larc.nasa.gov). In July 2011, the DISCOVER-AQ project conducted intensive air quality measurements in the Baltimore, MD and Washington, D.C. area in the eastern U.S. To take advantage of these unique data, the Community Multiscale Air Quality (CMAQ) model, coupled with the Weather Research and Forecasting (WRF) model is used to simulate the meteorology and air quality in the same region using 12-km, 4-km and 1-km horizontal grid spacings. The goal of the modeling exercise is to demonstrate the capability of the coupled WRF-CMAQ modeling system to simulate air quality at fine grid spacings in an urban area. Development of new data assimilation techniques and the use of higher resolution input data for the WRF model have been implemented to improve the meteorological results, particularly at the 4-km and 1-km grid resolutions. In addition, a number of updates to the CMAQ model were made to enhance the capability of the modeling system to accurately represent the magnitude and spatial distribution of pollutants at fine model resolutions. Data collected during the 2011 DISCOVER-AQ campa

“Application and evaluation of the two-way coupled WRF ...

EPA Pesticide Factsheets

The DISCOVER-AQ project (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality), is a joint collaboration between NASA, U.S. EPA and a number of other local organizations with the goal of characterizing air quality in urban areas using satellite, aircraft, vertical profiler and ground based measurements (http://discover-aq.larc.nasa.gov). In July 2011, the DISCOVER-AQ project conducted intensive air quality measurements in the Baltimore, MD and Washington, D.C. area in the eastern U.S. To take advantage of these unique data, the Community Multiscale Air Quality (CMAQ) model, coupled with the Weather Research and Forecasting (WRF) model is used to simulate the meteorology and air quality in the same region using 12-km, 4-km and 1-km horizontal grid spacings. The goal of the modeling exercise is to demonstrate the capability of the coupled WRF-CMAQ modeling system to simulate air quality at fine grid spacings in an urban area. Development of new data assimilation techniques and the use of higher resolution input data for the WRF model have been implemented to improve the meteorological results, particularly at the 4-km and 1-km grid resolutions. In addition, a number of updates to the CMAQ model were made to enhance the capability of the modeling system to accurately represent the magnitude and spatial distribution of pollutants at fine model resolutions. Data collected during the 2011 DISCOVER-AQ campa

77 FR 3417 - Approval and Promulgation of Air Quality Implementation Plans; Massachusetts; Determination of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-24

... recorded in EPA's Air Quality System (AQS) database. To account for missing data, the procedures found in... three-year period and then adjusts for missing data. In short, if the three-year average expected... ambient air quality monitoring data for the 2001-2003 monitoring period showing that the area had an...

Evaluation of the two-way coupled WRF-CMAQ modeling system to the 2011 DISCOVER-AQ campaign at 12-km, 4-km and 1-km resolutions

EPA Science Inventory

At the 12th Annual CMAS Conference initial results from the application of the coupled WRF-CMAQ modeling system to the 2011 Baltimore-Washington D.C. DISCOVER-AQ campaign were presented, with the focus on updates and new methods applied to the WRF modeling for fine-scale applicat...

Application of OMI NO2 for Regional Air Quality Model Evaluation

NASA Astrophysics Data System (ADS)

Holloway, T.; Bickford, E.; Oberman, J.; Scotty, E.; Clifton, O. E.

2012-12-01

To support the application of satellite data for air quality analysis, we examine how column NO2 measurements from the Ozone Monitoring Instrument (OMI) aboard the NASA Aura satellite relate to ground-based and model estimates of NO2 and related species. Daily variability, monthly mean values, and spatial gradients in OMI NO2 from the Netherlands Royal Meteorological Institute (KNMI) are compared to ground-based measurements of NO2 from the EPA Air Quality System (AQS) database. Satellite data is gridded to two resolutions typical of regional air quality models - 36 km x 36 km over the continental U.S., and 12 km x 12 km over the Upper Midwestern U.S. Gridding is performed using the Wisconsin Horizontal Interpolation Program for Satellites (WHIPS), a publicly available software to support gridding of satellite data to model grids. Comparing daily OMI retrievals (13:45 daytime local overpass time) with ground-based measurements (13:00), we find January and July 2007 correlation coefficients (r-values) generally positive, with values higher in the winter (January) than summer (July) for most sites. Incidences of anti-correlation or low-correlation are evaluated with model simulations from the U.S. EPA Community Multiscale Air Quality Model version 4.7 (CMAQ). OMI NO2 is also used to evaluate CMAQ output, and to compare performance metrics for CMAQ relative to AQS measurements. We compare simulated NO2 across both the U.S. and Midwest study domains with both OMI NO2 (total column CMAQ values, weighted with the averaging kernel) and with ground-based observations (lowest model layer CMAQ values). 2007 CMAQ simulations employ emissions from the Lake Michigan Air Directors Consortium (LADCO) and meteorology from the Weather Research and Forecasting (WRF) model. Over most of the U.S., CMAQ is too high in January relative to OMI NO2, but too low in January relative to AQS NO2. In contrast, CMAQ is too low in July relative to OMI NO2, but too high relative to AQS NO2. These

AirMSPI Data and Information

Atmospheric Science Data Center

2018-05-09

AirMSPI Data and Information   Airborne Multi-angle Spectro Polarimetric ... where 3-D radiative transfer may dominate, and (b) enable retrieval of aerosol and cloud macrophysical properties (distribution, height), ... MISR Home Page DISCOVER-AQ Information AirMSPI Announcements MISR Data Table ...

Monitoring Tropospheric Ozone Enhancement in the Front Range Using the Gsfc Tropoz DIAL during Discover - AQ 2014

NASA Astrophysics Data System (ADS)

Sullivan, J. T.; McGee, T. J.; Hoff, R. M.; Twigg, L.; Sumnicht, G. K.

2014-12-01

Tropospheric ozone profiles have been retrieved from the new ground based National Aeronautics and Space Administration (NASA) Goddard Space Flight Center TROPospheric OZone DIfferential Absorption Lidar (GSFC TROPOZ DIAL) in Fort Collins, CO from 200 m to 16 km AGL. These measurements were taken as part of NASA's DISCOVER-AQ campaign in July/August 2014. Measurements were made during simultaneous aircraft spirals over the lidar site as well as collocated ozonesonde launches. Ozone enhancement from local sources typically occurred in the mid-afternoon convection period, especially when there was light winds and low cloud cover. Interesting ozone profiles and time series data will be shown. Current atmospheric satellite instruments cannot peer through the optically thick stratospheric ozone layer to remotely sense boundary layer tropospheric ozone. In order to monitor this lower ozone more effectively, the Tropospheric Ozone Lidar Network (TOLNet) has been developed, which currently consists of five stations across the US. Three of these lidars, including the GSFC TROPOZ DIAL, recorded measurements during the DISCOVER-AQ campaign. The GSFC TROPOZ DIAL is based on the Differential Absorption Lidar (DIAL) technique, which currently detects two wavelengths, 289 and 299 nm. Ozone is absorbed more strongly at 289 nm than at 299 nm. The DIAL technique exploits this difference between the returned backscatter signals to obtain the ozone number density as a function of altitude. The transmitted wavelengths are generated by focusing the output of a quadrupled Nd:YAG laser beam (266 nm) into a pair of Raman cells, filled with high pressure hydrogen and deuterium. Stimulated Raman Scattering (SRS) within the focus generates a significant fraction of the pump energy at the first Stokes shift. With the knowledge of the ozone absorption coefficient at these two wavelengths, the range resolved number density can be derived.

75 FR 39635 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-12

..., quality-assured and certified ambient air quality monitoring data for the 2006-2008 ozone seasons that... data for the 2009 ozone season have been recorded in the EPA's Air Quality System (AQS) and show that... NAAQS through 2020 in the areas. EPA is approving the 2005 base year emissions inventories for the...

EPA True NO2 ground site measurements ?? multiple sites, TCEQ ground site measurements of meteorological and air pollution parameters ?? multiple sites ,GeoTASO NO2 Vertical Column

EPA Pesticide Factsheets

EPA True NO2 ground site measurements ?? multiple sites - http://www-air.larc.nasa.gov/cgi-bin/ArcView/discover-aq.tx-2013; TCEQ ground site measurements of meteorological and air pollution parameters ?? multiple sites - http://www-air.larc.nasa.gov/cgi-bin/ArcView/discover-aq.tx-2013; GeoTASO NO2 Vertical Column - http://www-air.larc.nasa.gov/cgi-bin/ArcView/discover-aq.tx-2013?FALCON=1This dataset is associated with the following publication:Nowlan, C., X. Lu, J. Leitch, K. Chance, G. González Abad, C. Lu, P. Zoogman, J. Cole, T. Delker, W. Good, F. Murcray, L. Ruppert, D. Soo, M. Follette-Cook, S. Janz, M. Kowalewski, C. Loughner, K. Pickering, J. Herman, M. Beaver, R. Long, J. Szykman, L. Judd, P. Kelley, W. Luke, X. Ren, and J. Al-Saadi. Nitrogen dioxide observations from the Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) airborne instrument: Retrieval algorithm and measurements during DISCOVER-AQ Texas 2013. Atmospheric Measurement Techniques. Copernicus Publications, Katlenburg-Lindau, GERMANY, 9(6): 2647-2668, (2016).

Biogenic isoprene emissions driven by regional weather predictions using different initialization methods: case studies during the SEAC4RS and DISCOVER-AQ airborne campaigns

NASA Astrophysics Data System (ADS)

Huang, Min; Carmichael, Gregory R.; Crawford, James H.; Wisthaler, Armin; Zhan, Xiwu; Hain, Christopher R.; Lee, Pius; Guenther, Alex B.

2017-08-01

Land and atmospheric initial conditions of the Weather Research and Forecasting (WRF) model are often interpolated from a different model output. We perform case studies during NASA's SEAC4RS and DISCOVER-AQ Houston airborne campaigns, demonstrating that using land initial conditions directly downscaled from a coarser resolution dataset led to significant positive biases in the coupled NASA-Unified WRF (NUWRF, version 7) surface and near-surface air temperature and planetary boundary layer height (PBLH) around the Missouri Ozarks and Houston, Texas, as well as poorly partitioned latent and sensible heat fluxes. Replacing land initial conditions with the output from a long-term offline Land Information System (LIS) simulation can effectively reduce the positive biases in NUWRF surface air temperature by ˜ 2 °C. We also show that the LIS land initialization can modify surface air temperature errors almost 10 times as effectively as applying a different atmospheric initialization method. The LIS-NUWRF-based isoprene emission calculations by the Model of Emissions of Gases and Aerosols from Nature (MEGAN, version 2.1) are at least 20 % lower than those computed using the coarser resolution data-initialized NUWRF run, and are closer to aircraft-observation-derived emissions. Higher resolution MEGAN calculations are prone to amplified discrepancies with aircraft-observation-derived emissions on small scales. This is possibly a result of some limitations of MEGAN's parameterization and uncertainty in its inputs on small scales, as well as the representation error and the neglect of horizontal transport in deriving emissions from aircraft data. This study emphasizes the importance of proper land initialization to the coupled atmospheric weather modeling and the follow-on emission modeling. We anticipate it to also be critical to accurately representing other processes included in air quality modeling and chemical data assimilation. Having more confidence in the weather

Hygroscopic Measurements of Aerosol Particles in the San Joaquin Valley California during the DRAGON and Discover AQ Campaign 2013

NASA Astrophysics Data System (ADS)

Orozco, D.; Delgado, R.; Hoff, R. M.

2013-12-01

In the ambient atmosphere, aerosol particles experience hygroscopic growth due to the influence of relative humidity (RH). Wet aerosols particles are larger than their dry equivalents, therefore they scatter more light. Quantitative knowledge of the RH effect and its influence on the light scattering coefficient on aerosol particles is of substantial importance when comparing ground based observations with other optical aerosol measurements techniques such satellite and sunphotometric retrievals of aerosol optical depth. The DISCOVER-AQ campaign is focused in improving the interpretation and relation between satellite observations and surface conditions related to air quality. In the winter of 2013, this campaign was held in the San Joaquin Valley, California, where systematic and concurrent observations of column integrated surface, and vertically resolved distributions of aerosols and trace gases relevant to air quality and their evolution during the day were observed. Different instruments such as particulate samplers, lidars, meteorological stations and airborne passive and active monitoring were coordinated to measure the aerosol structure of the San Joaquin Valley in a simultaneous fashion. A novel humidifier-dryer system for a TSI 3563 Nephelometer was implemented in the Penn State University NATIVE trailer located in Porterville California in order to measure the scattering coefficient σsp(λ) at three different wavelengths (λ=440, 550 and 700nm) in a RH range from 30 to 95%. The system was assembled by combining Nafion tubes to humidify and dry the aerosols and stepping motor valves to control the flow and the amount of humidity entering to the Nephelometer. Measurements in Porterville California reached dry scattering coefficient readings greater than 300Mm-1 at 550nm indicating the presence of a large amount of particles in the region. However, the ratio between scattering coefficients at high and low humidity, called the enhancement factor f

Trace Gas Measurements from the GeoTASO and GCAS Airborne Instruments: An Instrument and Algorithm Test-Bed for Air Quality Observations from Geostationary Orbit

NASA Astrophysics Data System (ADS)

Nowlan, C. R.; Liu, X.; Janz, S. J.; Leitch, J. W.; Al-Saadi, J. A.; Chance, K.; Cole, J.; Delker, T.; Follette-Cook, M. B.; Gonzalez Abad, G.; Good, W. S.; Kowalewski, M. G.; Loughner, C.; Pickering, K. E.; Ruppert, L.; Soo, D.; Szykman, J.; Valin, L.; Zoogman, P.

2016-12-01

The Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) and the GEO-CAPE Airborne Simulator (GCAS) instruments are pushbroom sensors capable of making remote sensing measurements of air quality and ocean color. Originally developed as test-bed instruments for the Geostationary Coastal and Air Pollution Events (GEO-CAPE) decadal survey, these instruments are now also part of risk reduction for the upcoming Tropospheric Emissions: Monitoring of Pollution (TEMPO) and Geostationary Environment Monitoring Spectrometer (GEMS) geostationary satellite missions, and will provide validation capabilities after the satellite instruments are in orbit. GeoTASO and GCAS flew on two different aircraft in their first intensive air quality field campaigns during the DISCOVER-AQ missions over Texas in 2013 and Colorado in 2014. GeoTASO was also deployed in 2016 during the KORUS-AQ field campaign to make measurements of trace gases and aerosols over Korea. GeoTASO and GCAS collect spectra of backscattered solar radiation in the UV and visible that can be used to derive 2-D maps of trace gas columns below the aircraft at spatial resolutions on the order of 250 x 500 m. We present spatially resolved maps of trace gas retrievals of ozone, nitrogen dioxide, formaldehyde and sulfur dioxide over urban areas and power plants from flights during the field campaigns, and comparisons with data from ground-based spectrometers, in situ monitoring instruments, and satellites.

Toolsets for Airborne Data

Atmospheric Science Data Center

2018-05-23

... from COlumn and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) Campaign including Maryland, Texas, California, and ... observations to diagnose near-surface conditions relating to air quality. To diagnose air quality conditions from space, reliable satellite ...

Regional characteristics of the relationship between columnar AOD and surface PM2.5: Application of lidar aerosol extinction profiles over Baltimore-Washington Corridor during DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Chu, D. Allen; Ferrare, Richard; Szykman, James; Lewis, Jasper; Scarino, Amy; Hains, Jennifer; Burton, Sharon; Chen, Gao; Tsai, Tzuchin; Hostetler, Chris; Hair, Johnathan; Holben, Brent; Crawford, James

2015-01-01

The first field campaign of DISCOVER-AQ (Deriving Information on Surface conditions from COlumn and VERtically resolved observations relevant to Air Quality) took place in July 2011 over Baltimore-Washington Corridor (BWC). A suite of airborne remote sensing and in-situ sensors was deployed along with ground networks for mapping vertical and horizontal distribution of aerosols. Previous researches were based on a single lidar station because of the lack of regional coverage. This study uses the unique airborne HSRL (High Spectral Resolution Lidar) data to baseline PM2.5 (particulate matter of aerodynamic diameter less than 2.5 μm) estimates and applies to regional air quality with satellite AOD (Aerosol Optical Depth) retrievals over BWC (∼6500 km2). The linear approximation takes into account aerosols aloft above AML (Aerosol Mixing Layer) by normalizing AOD with haze layer height (i.e., AOD/HLH). The estimated PM2.5 mass concentrations by HSRL AOD/HLH are shown within 2 RMSE (Root Mean Square Error ∼9.6 μg/m3) with correlation ∼0.88 with the observed over BWC. Similar statistics are shown when applying HLH data from a single location over the distance of 100 km. In other words, a single lidar is feasible to cover the range of 100 km with expected uncertainties. The employment of MPLNET-AERONET (MicroPulse Lidar NETwork - AErosol RObotic NETwork) measurements at NASA GSFC produces similar statistics of PM2.5 estimates as those derived by HSRL. The synergy of active and passive remote sensing aerosol measurements provides the foundation for satellite application of air quality on a daily basis. For the optimal range of 10 km, the MODIS-estimated PM2.5 values are found satisfactory at 27 (out of 36) sunphotometer locations with mean RMSE of 1.6-3.3 μg/m3 relative to PM2.5 estimated by sunphotometers. The remaining 6 of 8 marginal sites are found in the coastal zone, for which associated large RMSE values ∼4.5-7.8 μg/m3 are most likely due to

Analyzing source apportioned methane in northern California during Discover-AQ-CA using airborne measurements and model simulations

NASA Astrophysics Data System (ADS)

Johnson, Matthew S.; Yates, Emma L.; Iraci, Laura T.; Loewenstein, Max; Tadić, Jovan M.; Wecht, Kevin J.; Jeong, Seongeun; Fischer, Marc L.

2014-12-01

This study analyzes source apportioned methane (CH4) emissions and atmospheric mixing ratios in northern California during the Discover-AQ-CA field campaign using airborne measurement data and model simulations. Source apportioned CH4 emissions from the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 were applied in the 3-D chemical transport model GEOS-Chem and analyzed using airborne measurements taken as part of the Alpha Jet Atmospheric eXperiment over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV). During the time period of the Discover-AQ-CA field campaign EDGAR inventory CH4 emissions were ∼5.30 Gg day-1 (Gg = 1.0 × 109 g) (equating to ∼1.90 × 103 Gg yr-1) for all of California. According to EDGAR, the SFBA and northern SJV region contributes ∼30% of total CH4 emissions from California. Source apportionment analysis during this study shows that CH4 mixing ratios over this area of northern California are largely influenced by global emissions from wetlands and local/global emissions from gas and oil production and distribution, waste treatment processes, and livestock management. Model simulations, using EDGAR emissions, suggest that the model under-estimates CH4 mixing ratios in northern California (average normalized mean bias (NMB) = -5.2% and linear regression slope = 0.20). The largest negative biases in the model were calculated on days when large amounts of CH4 were measured over local emission sources and atmospheric CH4 mixing ratios reached values >2.5 parts per million. Sensitivity emission studies conducted during this research suggest that local emissions of CH4 from livestock management processes are likely the primary source of the negative model bias. These results indicate that a variety, and larger quantity, of measurement data needs to be obtained and additional research is necessary to better quantify source apportioned CH4 emissions in California.

Analyzing Source Apportioned Methane in Northern California During DISCOVER-AQ-CA Using Airborne Measurements and Model Simulations

NASA Technical Reports Server (NTRS)

Johnson, Matthew S.

2014-01-01

This study analyzes source apportioned methane (CH4) emissions and atmospheric concentrations in northern California during the Discover-AQ-CA field campaign using airborne measurement data and model simulations. Source apportioned CH4 emissions from the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 were applied in the 3-D chemical transport model GEOS-Chem and analyzed using airborne measurements taken as part of the Alpha Jet Atmospheric eXperiment over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV). During the time period of the Discover-AQ-CA field campaign EDGAR inventory CH4 emissions were 5.30 Gg/day (Gg 1.0 109 grams) (equating to 1.9 103 Gg/yr) for all of California. According to EDGAR, the SFBA and northern SJV region contributes 30 of total emissions from California. Source apportionment analysis during this study shows that CH4 concentrations over this area of northern California are largely influenced by global emissions from wetlands and local/global emissions from gas and oil production and distribution, waste treatment processes, and livestock management. Model simulations, using EDGAR emissions, suggest that the model under-estimates CH4 concentrations in northern California (average normalized mean bias (NMB) -5 and linear regression slope 0.25). The largest negative biases in the model were calculated on days when hot spots of local emission sources were measured and atmospheric CH4 concentrations reached values 3.0 parts per million (model NMB -10). Sensitivity emission studies conducted during this research suggest that local emissions of CH4 from livestock management processes are likely the primary source of the negative model bias. These results indicate that a variety, and larger quantity, of measurement data needs to be obtained and additional research is necessary to better quantify source apportioned CH4 emissions in California and further the understanding of the physical processes

Analyzing source apportioned methane in northern California during Discover-AQ-CA using airborne measurements and model simulations

DOE PAGES

Johnson, Matthew S.; Yates, Emma L.; Iraci, Laura T.; ...

2014-12-01

This study analyzes source apportioned methane (CH 4) emissions and atmospheric mixing ratios in northern California during the Discover-AQ-CA field campaign using airborne measurement data and model simulations. Source apportioned CH 4 emissions from the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 were applied in the 3-D chemical transport model GEOS-Chem and analyzed using airborne measurements taken as part of the Alpha Jet Atmospheric eXperiment over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV). During the time period of the Discover-AQ-CA field campaign EDGAR inventory CH 4 emissions were ~5.30 Gg day –1 (Ggmore » = 1.0 × 10 9 g) (equating to ~1.90 × 10 3 Gg yr –1) for all of California. According to EDGAR, the SFBA and northern SJV region contributes ~30% of total CH 4 emissions from California. Source apportionment analysis during this study shows that CH 4 mixing ratios over this area of northern California are largely influenced by global emissions from wetlands and local/global emissions from gas and oil production and distribution, waste treatment processes, and livestock management. Model simulations, using EDGAR emissions, suggest that the model under-estimates CH 4 mixing ratios in northern California (average normalized mean bias (NMB) = –5.2% and linear regression slope = 0.20). The largest negative biases in the model were calculated on days when large amounts of CH 4 were measured over local emission sources and atmospheric CH 4 mixing ratios reached values >2.5 parts per million. Sensitivity emission studies conducted during this research suggest that local emissions of CH 4 from livestock management processes are likely the primary source of the negative model bias. These results indicate that a variety, and larger quantity, of measurement data needs to be obtained and additional research is necessary to better quantify source apportioned CH 4 emissions in California.« less

U.S. NO₂ trends (2005–2013): EPA air quality system (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI)

DOE PAGES

Lamsal, Lok N.; Duncan, Bryan N.; Yoshida, Yasuko; ...

2015-06-01

Emissions of nitrogen oxides (NO x) and, subsequently, atmospheric levels of nitrogen dioxide (NO₂) have decreased over the U.S. due to a combination of environmental policies and technological change. Consequently, NO₂ levels have decreased by 30–40% in the last decade. We quantify NO₂ trends (2005–2013) over the U.S. using surface measurements from the U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) and an improved tropospheric NO₂ vertical column density (VCD) data product from the Ozone Monitoring Instrument (OMI) on the Aura satellite.We demonstrate that the current OMI NO₂ algorithm is of sufficient maturity to allow a favorable correspondence ofmore » trends and variations in OMI and AQS data. Our trend model accounts for the non-linear dependence of NO₂ concentration on emissions associated with the seasonal variation of the chemical lifetime, including the change in the amplitude of the seasonal cycle associated with the significant change in NO x emissions that occurred over the last decade. The direct relationship between observations and emissions becomes more robust when one accounts for these non-linear dependencies. We improve the OMI NO₂ standard retrieval algorithm and, subsequently, the data product by using monthly vertical concentration profiles, a required algorithm input, from a high-resolution chemistry and transport model (CTM) simulation with varying emissions (2005-2013). The impact of neglecting the time-dependence of the profiles leads to errors in trend estimation, particularly in regions where emissions have changed substantially. For example, trends calculated from retrievals based on time-dependent profiles offer 18% more instances of significant trends and up to 15% larger total NO₂ reduction versus the results based on profiles for 2005. Using a CTM, we explore the theoretical relation of the trends estimated from NO₂ VCDs to those estimated from ground-level concentrations. The model

U.S. NO₂ trends (2005–2013): EPA air quality system (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamsal, Lok N.; Duncan, Bryan N.; Yoshida, Yasuko

Emissions of nitrogen oxides (NO x) and, subsequently, atmospheric levels of nitrogen dioxide (NO₂) have decreased over the U.S. due to a combination of environmental policies and technological change. Consequently, NO₂ levels have decreased by 30–40% in the last decade. We quantify NO₂ trends (2005–2013) over the U.S. using surface measurements from the U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) and an improved tropospheric NO₂ vertical column density (VCD) data product from the Ozone Monitoring Instrument (OMI) on the Aura satellite.We demonstrate that the current OMI NO₂ algorithm is of sufficient maturity to allow a favorable correspondence ofmore » trends and variations in OMI and AQS data. Our trend model accounts for the non-linear dependence of NO₂ concentration on emissions associated with the seasonal variation of the chemical lifetime, including the change in the amplitude of the seasonal cycle associated with the significant change in NO x emissions that occurred over the last decade. The direct relationship between observations and emissions becomes more robust when one accounts for these non-linear dependencies. We improve the OMI NO₂ standard retrieval algorithm and, subsequently, the data product by using monthly vertical concentration profiles, a required algorithm input, from a high-resolution chemistry and transport model (CTM) simulation with varying emissions (2005-2013). The impact of neglecting the time-dependence of the profiles leads to errors in trend estimation, particularly in regions where emissions have changed substantially. For example, trends calculated from retrievals based on time-dependent profiles offer 18% more instances of significant trends and up to 15% larger total NO₂ reduction versus the results based on profiles for 2005. Using a CTM, we explore the theoretical relation of the trends estimated from NO₂ VCDs to those estimated from ground-level concentrations. The model

The impact of frequency and duration of air quality monitoring: Atlanta, GA, data modeling of air pollution and mortality.

PubMed

Klemm, Rebecca J; Thomas, Eddie L; Wyzga, Ronald E

2011-11-01

The purpose of this analysis is threefold. We first examine the extent to which a longer series of data improves our understanding of air pollution on human mortality in the Atlanta, GA, area by updating the findings presented in Klemm and Mason (J. Air Waste Manage. Assoc. 2000, 50, 1433-1439) and Klemm et al. (Inhal. Toxicol. 2004, 16 (Suppl 1), 131-141) with 7.5 additional years of data. We explore estimated effects on two age groups (<65 and 65+) and four categories of cause of death. Second, we investigate how enlarging the geographic area of inquiry influences the estimated effects. Third, because some air quality (AQ) measures are monitored less frequently than daily, we investigate the extent to which AQ measurement frequency can influence estimates of relationships with human mortality. Our analytical approach employs a Poisson regression model using generalized linear modeling in S-Plus to estimate the relationship between daily AQ measures and daily mortality counts. We show that the estimated effects and their associated t values vary by year for nine AQ measures (particulate matter with aerodynamic diameter < or =2.5 microm [PM2.5], elemental carbon [EC], organic carbon [OC], NO3, SO4, O3, NO2, CO, and SO2). Several of the estimated AQ effects show downward trends during the 9-year period of study. The estimated effects tend to be strongest for the AQ measurement during the day of death and tend to decrease with additional lags. Enlarging the geographic area from two to four counties in the metropolitan area decreased the estimated effects, perhaps partly due to the fact that the measurement site is located in one of the two original counties. Estimated effects utilizing data as if the AQ were only measured every 3rd or every 6th day each week or twice per week vary from lower to higher than that estimated with daily measurements, although the t values are lower, as expected.

Development of the GEM-MACH-FireWork System: An Air Quality Model with On-line Wildfire Emissions within the Canadian Operational Air Quality Forecast System

NASA Astrophysics Data System (ADS)

Pavlovic, Radenko; Chen, Jack; Beaulieu, Paul-Andre; Anselmp, David; Gravel, Sylvie; Moran, Mike; Menard, Sylvain; Davignon, Didier

2014-05-01

A wildfire emissions processing system has been developed to incorporate near-real-time emissions from wildfires and large prescribed burns into Environment Canada's real-time GEM-MACH air quality (AQ) forecast system. Since the GEM-MACH forecast domain covers Canada and most of the U.S.A., including Alaska, fire location information is needed for both of these large countries. During AQ model runs, emissions from individual fire sources are injected into elevated model layers based on plume-rise calculations and then transport and chemistry calculations are performed. This "on the fly" approach to the insertion of the fire emissions provides flexibility and efficiency since on-line meteorology is used and computational overhead in emissions pre-processing is reduced. GEM-MACH-FireWork, an experimental wildfire version of GEM-MACH, was run in real-time mode for the summers of 2012 and 2013 in parallel with the normal operational version. 48-hour forecasts were generated every 12 hours (at 00 and 12 UTC). Noticeable improvements in the AQ forecasts for PM2.5 were seen in numerous regions where fire activity was high. Case studies evaluating model performance for specific regions and computed objective scores will be included in this presentation. Using the lessons learned from the last two summers, Environment Canada will continue to work towards the goal of incorporating near-real-time intermittent wildfire emissions into the operational air quality forecast system.

Constraining ammonia dairy emissions during NASA DISCOVER-AQ California: surface and airborne observation comparisons with CMAQ simulations

NASA Astrophysics Data System (ADS)

Miller, D. J.; Liu, Z.; Sun, K.; Tao, L.; Nowak, J. B.; Bambha, R.; Michelsen, H. A.; Zondlo, M. A.

2014-12-01

Agricultural ammonia (NH3) emissions are highly uncertain in current bottom-up inventories. Ammonium nitrate is a dominant component of fine aerosols in agricultural regions such as the Central Valley of California, especially during winter. Recent high resolution regional modeling efforts in this region have found significant ammonium nitrate and gas-phase NH3 biases during summer. We compare spatially-resolved surface and boundary layer gas-phase NH3 observations during NASA DISCOVER-AQ California with Community Multi-Scale Air Quality (CMAQ) regional model simulations driven by the EPA NEI 2008 inventory to constrain wintertime NH3 model biases. We evaluate model performance with respect to aerosol partitioning, mixing and deposition to constrain contributions to modeled NH3 concentration biases in the Central Valley Tulare dairy region. Ammonia measurements performed with an open-path mobile platform on a vehicle are gridded to 4 km resolution hourly background concentrations. A peak detection algorithm is applied to remove local feedlot emission peaks. Aircraft NH3, NH4+ and NO3- observations are also compared with simulations extracted along the flight tracks. We find NH3 background concentrations in the dairy region are underestimated by three to five times during winter and NH3 simulations are moderately correlated with observations (r = 0.36). Although model simulations capture NH3 enhancements in the dairy region, these simulations are biased low by 30-60 ppbv NH3. Aerosol NH4+ and NO3- are also biased low in CMAQ by three and four times respectively. Unlike gas-phase NH3, CMAQ simulations do not capture typical NH4+ or NO3- enhancements observed in the dairy region. In contrast, boundary layer height simulations agree well with observations within 13%. We also address observational constraints on simulated NH3 deposition fluxes. These comparisons suggest that NEI 2008 wintertime dairy emissions are underestimated by a factor of three to five. We test

Spatial Variability in Black Carbon Mixing State Observed During The Multi-City NASA DISCOVER-AQ Field Campaign

NASA Astrophysics Data System (ADS)

Moore, R.; Ziemba, L. D.; Beyersdorf, A. J.; Chen, G.; Corr, C.; Hudgins, C.; Martin, R.; Shook, M.; Thornhill, K. L., II; Winstead, E.; Anderson, B. E.

2014-12-01

Light absorbing carbonaceous aerosols are known to be an important climatic driver with a global radiative forcing of about half (IPCC, 2013) to two-thirds (Bond et al., 2013) that of the dominant greenhouse gas, carbon dioxide. While the mass absorption coefficient of pure black carbon (BC) is fairly well known, observational evidence suggests that BC rapidly mixes with other aerosol chemical components within hours of emission (Moffet and Prather, 2009; Moteki et al., 2007). These other components may include predominantly scattering organic, sulfate, and nitrate species, as well as light-absorbing, so-called "brown carbon" (BrC). It has been suggested that the presence of these BC-mixed components may induce mixing-state-dependent lensing effects that could potentially double the BC direct radiative forcing (Jacobson, 2001). The key to better understanding how BC-rich aerosols are distributed in the atmosphere is to examine an unbiased set of measurements covering broad spatial and temporal coverage; however, many past airborne field campaigns have specifically targeted source plumes or other scientifically-relevant emissions sources. The recent NASA DISCOVER-AQ campaign is unique in that approximately the same flight pattern was performed over a month-long period in each of four different U.S. metropolitan areas, ensuring an unbiased, or at least less biased, data set with both wide horizontal and vertical (surface to 5 km altitude) coverage. We present a statistical analysis of BC-rich particle mixing state measured during DISCOVER-AQ by a DMT Single Particle Soot Photometer (SP2). The SP2 measures the BC mass distribution via laser incandescence, and the non-BC coating thickness is inferred from the light scattering signal of particles greater than 200 nm in diameter (Gao et al., 2007; Moteki and Kondo, 2008). The SP2-derived size distributions are compared to optical scattering size distributions measured by an UHSAS in order determine 1) the externally

Chemical composition of aerosol measurements in the air pollution plume during KORUS-AQ

NASA Astrophysics Data System (ADS)

Park, T.; Lee, J. B.; Lim, Y. J.; Ahn, J.; Park, J. S.; Soo, C. J.; Kim, J.; Park, S.; Lee, Y.; Desyaterik, Y.; Collett, J. L., Jr.; Lee, T.

2017-12-01

The Korean peninsula is a great place to study different sources of the aerosols: urban, rural and marine. In addition, Seoul is one of the large metropolitan areas in the world and has a variety of sources because half of the Korean population lives in Seoul, which comprises only 12% of the country's area. To understand the chemical composition of aerosol form long-range transport and local sources better, an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed on an airborne platform (NASA DC-8 aircraft). The HR-ToF-AMS is capable of measuring non-refractory size resolved chemical composition of submicron particle(NR-PM1) in the air pollution plume, including mass concentration of organic carbon, nitrate, sulfate, and ammonium with 10 seconds time resolution. The measurements were performed twenty times research flight for understanding characteristic of the air pollution from May to June, 2016 on the South Korean peninsula during KORUS-AQ 2016 campaign. The scientific goal of this study is to characterize aerosol chemical properties and mass concentration in order to understand the role of the long-range transport from northeast Asia to South Korea, and influence of the local sources. To brief, organics dominated during all of flights. Also, organics and nitrate were dominant around energy industrial complex near by Taean, South Korea. The presentation will provide an overview of the composition of NR-PM1 measured in air pollution plumes, and deliver detail information about width, depth and spatial distribution of the pollutant in the air pollution plumes. The results of this study will provide high temporal and spatial resolved details on the air pollution plumes, which are valuable input parameters of aerosol properties for the current air quality models.

Observations of Radical Precursors during TexAQS II: Findings and Implications

NASA Astrophysics Data System (ADS)

Olaguer, E. P.; Lefer, B. L.; Rappenglueck, B.; Pinto, J. P.

2009-12-01

The Texas Environmental Research Consortium (TERC) sponsored and helped organize significant components of the Second Texas Air Quality Study (TexAQS II). Some of the TERC-sponsored experiments, most notably those associated with the TexAQS II Radical and Aerosol Measurement Project (TRAMP) sited on top of the Moody Tower at the University of Houston, found evidence for the importance of short-lived radical sources such as formaldehyde (HCHO) and nitrous acid (HONO) in increasing ozone productivity. During TRAMP, daytime HCHO pulses as large as 32 ppb were observed and attributed to industrial activities upwind in the Houston Ship Channel (HSC), and HCHO peaks as large as 52 ppb were detected by in-situ surface monitors in the HSC. In addition, an instrumented Piper Aztec aircraft observed plumes of apparent primary formaldehyde in flares from petrochemical facilities in the HSC. In one such combustion plume, depleted of ozone by large NOx emissions, the Piper Aztec measured an HCHO-to-CO ratio three times that of mobile sources. HCHO from uncounted primary sources or ozonolysis of underestimated olefin emissions could significantly increase ozone productivity in Houston beyond previous expectations. Simulations with the CAMx model show that additional emissions of HCHO from industrial flares can increase peak ozone in Houston by up to 30 ppb, depending on conditions in the planetary boundary layer. Other findings from TexAQS II include significant concentrations of HONO throughout the day, well in excess of current air quality model predictions, with large nocturnal vertical gradients indicating a surface or near-surface source of HONO, and large concentrations of night-time radicals (~30 ppt HO2). Additional HONO sources could increase daytime ozone by more than 10 ppb. Improving the representation of primary and secondary HCHO and HONO in air quality models could enhance the effectiveness of simulated control strategies, and thus make ozone attainment

Influences of emission sources and meteorology on aerosol chemistry in a polluted urban environment: Results from DISCOVER-AQ California

DOE PAGES

Young, Dominique E.; Kim, Hwajin; Parworth, Caroline; ...

2016-05-02

The San Joaquin Valley (SJV) in California experiences persistent air-quality problems associated with elevated particulate matter (PM) concentrations due to anthropogenic emissions, topography, and meteorological conditions. Thus it is important to unravel the various sources and processes that affect the physicochemical properties of PM in order to better inform pollution abatement strategies and improve parameterizations in air-quality models. During January and February 2013, a ground supersite was installed at the Fresno–Garland California Air Resources Board (CARB) monitoring station, where comprehensive, real-time measurements of PM and trace gases were performed using instruments including an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) andmore » an Ionicon proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) as part of the NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaign. The average submicron aerosol (PM 1) concentration was 31.0 µg m −3 and the total mass was dominated by organic aerosols (OA, 55 %), followed by ammonium nitrate (35 %). High PM pollution events were commonly associated with elevated OA concentrations, mostly from primary sources. Organic aerosols had average atomic oxygen-to-carbon (O / C), hydrogen-to-carbon (H / C), and nitrogen-to-carbon (N / C) ratios of 0.42, 1.70, and 0.017, respectively. Six distinct sources of organic aerosol were identified from positive matrix factorization (PMF) analysis of the AMS data: hydrocarbon-like OA (HOA; 9 % of total OA, O / C  =  0.09) associated with local traffic, cooking OA (COA; 18 % of total OA, O / C  =  0.19) associated with food cooking activities, two biomass burning OA (BBOA1: 13 % of total OA, O / C  =  0.33; BBOA2: 20 % of total OA, O / C  =  0.60) most likely

Influences of emission sources and meteorology on aerosol chemistry in a polluted urban environment: results from DISCOVER-AQ California

NASA Astrophysics Data System (ADS)

Young, Dominique E.; Kim, Hwajin; Parworth, Caroline; Zhou, Shan; Zhang, Xiaolu; Cappa, Christopher D.; Seco, Roger; Kim, Saewung; Zhang, Qi

2016-05-01

The San Joaquin Valley (SJV) in California experiences persistent air-quality problems associated with elevated particulate matter (PM) concentrations due to anthropogenic emissions, topography, and meteorological conditions. Thus it is important to unravel the various sources and processes that affect the physicochemical properties of PM in order to better inform pollution abatement strategies and improve parameterizations in air-quality models. During January and February 2013, a ground supersite was installed at the Fresno-Garland California Air Resources Board (CARB) monitoring station, where comprehensive, real-time measurements of PM and trace gases were performed using instruments including an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and an Ionicon proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) as part of the NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaign. The average submicron aerosol (PM1) concentration was 31.0 µg m-3 and the total mass was dominated by organic aerosols (OA, 55 %), followed by ammonium nitrate (35 %). High PM pollution events were commonly associated with elevated OA concentrations, mostly from primary sources. Organic aerosols had average atomic oxygen-to-carbon (O / C), hydrogen-to-carbon (H / C), and nitrogen-to-carbon (N / C) ratios of 0.42, 1.70, and 0.017, respectively. Six distinct sources of organic aerosol were identified from positive matrix factorization (PMF) analysis of the AMS data: hydrocarbon-like OA (HOA; 9 % of total OA, O / C = 0.09) associated with local traffic, cooking OA (COA; 18 % of total OA, O / C = 0.19) associated with food cooking activities, two biomass burning OA (BBOA1: 13 % of total OA, O / C = 0.33; BBOA2: 20 % of total OA, O / C = 0.60) most likely associated with residential space heating from wood combustion, and semivolatile oxygenated OA (SV

Influences of emission sources and meteorology on aerosol chemistry in a polluted urban environment: results from DISCOVER-AQ California

NASA Astrophysics Data System (ADS)

Young, D. E.; Kim, H.; Parworth, C.; Zhou, S.; Zhang, X.; Cappa, C. D.; Seco, R.; Kim, S.; Zhang, Q.

2015-12-01

The San Joaquin Valley (SJV) in California experiences persistent air quality problems associated with elevated particulate matter (PM) concentrations due to anthropogenic emissions, topography, and meteorological conditions. Thus it is important to unravel the various sources and processes that affect the physico-chemical properties of PM in order to better inform pollution abatement strategies and improve parameterizations in air quality models. Air Resources Board (CARB) monitoring station, where comprehensive, real-time measurements of PM and trace gases were performed using instruments including an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and an Ionicon Proton Transfer Reaction Time-of-Flight Mass Spectrometer (PTR-TOF-MS) as part of the NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaign. The average submicron aerosol (PM1) concentration was 31.0 μg m-3 and the total mass was dominated by organic aerosols (OA, 55 %), followed by ammonium nitrate (35 %). High PM pollution events were commonly associated with elevated OA concentrations, mostly from primary sources. Organic aerosols had average atomic oxygen-to-carbon (O / C), hydrogen-to-carbon (H / C), and nitrogen-to-carbon (N / C) ratios of 0.42, 1.70, and 0.017, respectively. Six distinct sources of organic aerosol were identified from positive matrix factorization (PMF) analysis of the AMS data: hydrocarbon-like OA (HOA; 9 % of total OA; O / C = 0.09) associated with local traffic, cooking OA (COA; 28 % of total OA; O / C = 0.19) associated with food cooking activities, two biomass burning OAs (BBOA1; 13 % of total OA; O / C = 0.33 and BBOA2; 20 % of total OA; O / C = 0.60) most likely associated with residential space heating from wood combustion, and semi

Multiple Sensitivity Testing for Regional Air Quality Model in summer 2014

NASA Astrophysics Data System (ADS)

Tang, Y.; Lee, P.; Pan, L.; Tong, D.; Kim, H. C.; Huang, M.; Wang, J.; McQueen, J.; Lu, C. H.; Artz, R. S.

2015-12-01

The NOAA Air Resources laboratory leads to improve the performance of the U.S. Air Quality Forecasting Capability (NAQFC). It is operational in NOAA National Centers for Environmental Prediction (NCEP) which focuses on predicting surface ozone and PM2.5. In order to improve its performance, we tested several approaches, including NOAA Environmental Modeling System Global Aerosol Component (NGAC) simulation derived ozone and aerosol lateral boundary conditions (LBC), bi-direction NH3 emission and HMS(Hazard Mapping System)-BlueSky emission with the latest U.S. EPA Community Multi-scale Air Quality model (CMAQ) version and the U.S EPA National Emission Inventory (NEI)-2011 anthropogenic emissions. The operational NAQFC uses static profiles for its lateral boundary condition (LBC), which does not impose severe issue for near-surface air quality prediction. However, its degraded performance for the upper layer (e.g. above 3km) is evident when comparing with aircraft measured ozone. NCEP's Global Forecast System (GFS) has tracer O3 prediction treated as 3-D prognostic variable (Moorthi and Iredell, 1998) after being initialized with Solar Backscatter Ultra Violet-2 (SBUV-2) satellite data. We applied that ozone LBC to the CMAQ's upper layers and yield more reasonable O3 prediction than that with static LBC comparing with the aircraft data in Discover-AQ Colorado campaign. NGAC's aerosol LBC also improved the PM2.5 prediction with more realistic background aerosols. The bi-direction NH3 emission used in CMAQ also help reduce the NH3 and nitrate under-prediction issue. During summer 2014, strong wildfires occurred in northwestern USA, and we used the US Forest Service's BlueSky fire emission with HMS fire counts to drive CMAQ and tested the difference of day-1 and day-2 fire emission estimation. Other related issues were also discussed.

The organic trace gas composition over South Korea as measured by PTR-ToF-MS during KORUS-AQ

NASA Astrophysics Data System (ADS)

Wisthaler, A.; Eichler, P.; Kaser, L.; Mikoviny, T.; Müller, M.

2017-12-01

Nonmethane organic gases (NMOGs) are important air quality constituents. Many of them act as precursors to ozone and fine particles and some NMOGs (e.g. benzene) are classified as air toxics. During the Korea-United States Air Quality (KORUS-AQ) study in May and June of 2016, we deployed a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) aboard the NASA DC-8 for measuring NMOGs at high speed (10 Hz) and sensitivity (ppt levels). The aircraft sampled emissions from a variety of point and area sources (e.g. urban emissions from Seoul and Daegu, industrial emission from the Daesan and Ulsan complexes, biogenic emissions over central South Korea and agricultural fire emissions in the Western provinces) as well as the pollution inflow from the Yellow Sea. We will provide an overview of NMOG profiles associated with these sources, give an estimate of emission rates where possible, and discuss potential implications for local and regional air quality. We will further give examples on how NMOG tracers can be used for source characterization and highlight findings that should undergo future collaborative analyses within the KORUS-AQ Science Team.

Satellite Maps and Relevant Compositional Properties of PM2.5 in Difficult Winter Situations and Comparisons to DISCOVER-AQ Airborne Sampling

NASA Technical Reports Server (NTRS)

Chatfield, Robert B.

2016-01-01

Mediterranean-climate regions like California's San Joaquin Valley are subject to severe wintertime particulate pollution affecting public health. We present maps of episodes and particulate diagnostics to aid diagnosis and amelioration. For abatement at sources, we require an understanding of sources and transport. Remote sensing should be of aid, but radiance-to-particle relationships are far different from methods which have been of use in the Eastern USA, Northern and Central Europe. Here are the problems: (a) Thin if very polluted mixed layers (MLs) yield optical depths, AOD, near the detection level, (b) bright and quite variegated surfaces (c) Unusual particle composition (e.g., predominance of NH4NO3 and fireplace buning aerosol), which complicate the relationship of AOD to PM2.5. Specialized analysis of MODIS-Aqua data to obtain AOD using the multi-angle (MAIAC) technique employed by Lyapustin and Wang. Meteorological analyses like NOAA's Rapid Analysis Product (RAP, or newer products like HRRR), which are formulated to remain close to observations (e.g. of water), provide useful ML information corroborated by DISCOVER-AQ in-situ and lidar observations. The many PM2.5 measurements allow a calibration of these products and thus maps of aerosol on many successive aerosol buildups. These calibrations also allow insight into compositional information relevant to MODIS retrievals, the product of aerosol density and specific scattering. We have found that the rich in-situ, lidar, and sun-photometer data sets of NASA'S DISCOVER-AQ data set (2013) of great aid. We will highlight the most interesting of many intercomparisons possible with this rich data set. We conclude with a description of new work to extend these insights to similar regions, e.g. the Imperial Valley of California, the Po Valley and maritime Southern Europe, and the litoral regions of Israel.

Source apportionment of organic aerosol across Houston, TX during DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Yoon, S.; Clark, A. E.; Ortiz, S. M.; Usenko, S.; Sheesley, R. J.

2015-12-01

As part of the ground-based sampling efforts during DISCOVER-AQ's Houston month-long campaign in September 2013, atmospheric particulate matter (PM) samples were collected at four sites: Moody Tower (urban), Manvel Croix (southern suburb), Conroe (northern suburb), and La Porte (urban industrial). The Houston metropolitan area, especially the Houston Ship Channel, is a densely industrialized urban city with large concentrations of petroleum refining, petrochemical manufacturing, and heavy traffic during peak hours. Due to these and other emission sources, the area is heavily impacted by ambient PM. This study will be looking at fine PM (diameter less than 2.5µm, PM2.5) from all four sites. PM2.5fraction is relevant for understanding fate and transport of organic contaminants and is widely known to negatively impact human health. Chemical analysis including radiocarbon (14C) and organic tracer measurements (polycyclic aromatic hydrocarbons, alkanes, hopanes, steranes, and levoglucosan) were used for source apportionment. The 14C measurements constrained CMB results to estimate both primary and secondary contributions to total organic carbon (TOC). Results indicate that Moody Tower had consistent primary motor vehicle exhaust contribution (18-27%) and a fossil secondary organic aerosol (SOA) contribution from 5-33% depending on atmospheric conditions. Conroe had a lower contribution of motor vehicle exhaust (5-10%) and similarly variable fraction of fossil SOA (4-25%). Manvel Croix had an interim motor vehicle contribution (9-15%) with a variable fossil SOA (5-30%). For contemporary OC, there was minimal contribution of wood smoke during examined weeks (0-9%) but larger contributor of biogenic SOA ranging from 40-75% at Moody Tower, 56-81% at Manvel Croix and 60-79% at Conroe. Overall, the motor vehicle contribution was consistent at each site during the analysis week, biogenic SOA was consistently high, while fossil SOA showed the most variability.

Monitoring Indoor Air Quality for Enhanced Occupational Health.

PubMed

Pitarma, Rui; Marques, Gonçalo; Ferreira, Bárbara Roque

2017-02-01

Indoor environments are characterized by several pollutant sources. Because people spend more than 90% of their time in indoor environments, several studies have pointed out the impact of indoor air quality on the etiopathogenesis of a wide number of non-specific symptoms which characterizes the "Sick Building Syndrome", involving the skin, the upper and lower respiratory tract, the eyes and the nervous system, as well as many building related diseases. Thus, indoor air quality (IAQ) is recognized as an important factor to be controlled for the occupants' health and comfort. The majority of the monitoring systems presently available is very expensive and only allow to collect random samples. This work describes the system (iAQ), a low-cost indoor air quality monitoring wireless sensor network system, developed using Arduino, XBee modules and micro sensors, for storage and availability of monitoring data on a web portal in real time. Five micro sensors of environmental parameters (air temperature, humidity, carbon monoxide, carbon dioxide and luminosity) were used. Other sensors can be added for monitoring specific pollutants. The results reveal that the system can provide an effective indoor air quality assessment to prevent exposure risk. In fact, the indoor air quality may be extremely different compared to what is expected for a quality living environment. Systems like this would have benefit as public health interventions to reduce the burden of symptoms and diseases related to "sick buildings".

Current State of the Evidence: Air Pollution Impacts on Human Health

EPA Science Inventory

Epidemiologic studies have demonstrated a consistent association between ambient levels of air pollution and adverse human health effects, including mortality and morbidity. Many of these studies have relied on the US Air Quality System (AQS) for exposure assessment. The AQS is a...

Application and evaluation of high-resolution WRF-CMAQ with simple urban parameterization.

EPA Science Inventory

The 2-way coupled WRF-CMAQ meteorology and air quality modeling system is evaluated for high-resolution applications by comparing to a regional air quality field study (Discover-AQ). The model was modified to better account for the effects of urban environments. High-resolution...

Application and evaluation of high-resolution WRF-CMAQ with simple urban parameterization

EPA Science Inventory

The 2-way coupled WRF-CMAQ meteorology and air quality modeling system is evaluated for high-resolution applications by comparing to a regional air quality field study (Discover-AQ). The model was modified to better account for the effects of urban environments. High-resolution...

Bay Breeze Influence on Surface Ozone at Edgewood, MD During July 2011

NASA Technical Reports Server (NTRS)

Stauffer, Ryan M.; Thompson, Anne M.; Martins, Douglas K.; Clark, Richard D.; Goldberg, Daniel L.; Loughner, Christopher P.; Delgado, Ruben; Dickerson, Russell R.; Stehr, Jeffrey W.; Tzortziou, Maria A.

2012-01-01

Surface ozone (O3) was analyzed to investigate the role of the bay breeze on air quality at two locations in Edgewood, Maryland (lat: 39.4deg, lon: -76.3deg) for the month of July 2011. Measurements were taken as part of the first year of NASA's "Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) Earth Venture campaign and as part of NASA's Geostationary for Coastal and Air Pollution Events Chesapeake Bay Oceanographic campaign with DISCOVER-AQ (Geo-CAPE CBODAQ). Geo-CAPE CBODAQ complements DISCOVER-AQ by providing ship-based observations over the Chesapeake Bay. A major goal of DISCOVER-AQ is determining the relative roles of sources, photochemistry and local meteorology during air quality events in the Mid-Atlantic region of the U.S. Surface characteristics, transport and vertical structures of O3 during bay breezes were identified using in-situ surface, balloon and aircraft data, along with remote sensing equipment. Localized late day peaks in O3 were observed during bay breeze days, maximizing an average of 3 h later compared to days without bay breezes. Of the 10 days of July 2011 that violated the U.S. Environmental Protection Agency (EPA) 8 h O3 standard of 75 parts per billion by volume (ppbv) at Edgewood, eight exhibited evidence of a bay breeze circulation. The results indicate that while bay breezes and the processes associated with them are not necessary to cause exceedances in this area, bay breezes exacerbate poor air quality that sustains into the late evening hours at Edgewood. The vertical and horizontal distributions of O3 from the coastal Edgewood area to the bay also show large gradients that are often determined by boundary layer stability. Thus, developing air quality models that can sufficiently resolve these dynamics and associated chemistry, along with more consistent monitoring of O3 and meteorology on and along the complex coastline of Chesapeake Bay must be a

Bay breeze influence on surface ozone at Edgewood, MD during July 2011.

PubMed

Stauffer, Ryan M; Thompson, Anne M; Martins, Douglas K; Clark, Richard D; Goldberg, Daniel L; Loughner, Christopher P; Delgado, Ruben; Dickerson, Russell R; Stehr, Jeffrey W; Tzortziou, Maria A

Surface ozone (O 3 ) was analyzed to investigate the role of the bay breeze on air quality at two locations in Edgewood, Maryland (lat: 39.4°, lon: -76.3°) for the month of July 2011. Measurements were taken as part of the first year of NASA's "Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) Earth Venture campaign and as part of NASA's Geostationary for Coastal and Air Pollution Events Chesapeake Bay Oceanographic campaign with DISCOVER-AQ (Geo-CAPE CBODAQ). Geo-CAPE CBODAQ complements DISCOVER-AQ by providing ship-based observations over the Chesapeake Bay. A major goal of DISCOVER-AQ is determining the relative roles of sources, photochemistry and local meteorology during air quality events in the Mid-Atlantic region of the U.S. Surface characteristics, transport and vertical structures of O 3 during bay breezes were identified using in-situ surface, balloon and aircraft data, along with remote sensing equipment. Localized late day peaks in O 3 were observed during bay breeze days, maximizing an average of 3 h later compared to days without bay breezes. Of the 10 days of July 2011 that violated the U.S. Environmental Protection Agency (EPA) 8 h O 3 standard of 75 parts per billion by volume (ppbv) at Edgewood, eight exhibited evidence of a bay breeze circulation. The results indicate that while bay breezes and the processes associated with them are not necessary to cause exceedances in this area, bay breezes exacerbate poor air quality that sustains into the late evening hours at Edgewood. The vertical and horizontal distributions of O 3 from the coastal Edgewood area to the bay also show large gradients that are often determined by boundary layer stability. Thus, developing air quality models that can sufficiently resolve these dynamics and associated chemistry, along with more consistent monitoring of O 3 and meteorology on and along the complex coastline of Chesapeake Bay

76 FR 72377 - Approval and Promulgation of Air Quality Implementation Plans; Connecticut; Determinations of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-23

... recorded in EPA's Air Quality System (AQS) database. To account for missing data, the procedures found in... Site Year exceedance exceedance expected days over days for exceedance 0.124 ppm missing data rate... for exceedance 0.124 ppm missing data rate 090050006 Cornwall........ 2006 0 0.0 0.3 2007 1 1.0 2008 0...

Performance and diagnostic evaluation of ozone predictions by the Eta-Community Multiscale Air Quality Forecast System during the 2002 New England Air Quality Study.

PubMed

Yu, Shaocai; Mathur, Rohit; Kang, Daiwen; Schere, Kenneth; Eder, Brian; Pleim, Jonathan

2006-10-01

A real-time air quality forecasting system (Eta-Community Multiscale Air Quality [CMAQ] model suite) has been developed by linking the National Centers for Environmental Estimation Eta model to the U.S. Environmental Protection Agency (EPA) CMAQ model. This work presents results from the application of the Eta-CMAQ modeling system for forecasting ozone (O3) over the Northeastern United States during the 2002 New England Air Quality Study (NEAQS). Spatial and temporal performance of the Eta-CMAQ model for O3 was evaluated by comparison with observations from the EPA Air Quality System (AQS) network. This study also examines the ability of the model to simulate the processes governing the distributions of tropospheric O3 on the basis of the intensive datasets obtained at the four Atmospheric Investigation, Regional Modeling, Analysis, and Estimation (AIRMAP) and Harvard Forest (HF) surface sites. The episode analysis reveals that the model captured the buildup of O3 concentrations over the northeastern domain from August 11 and reproduced the spatial distributions of observed O3 very well for the daytime (8:00 p.m.) of both August 8 and 12 with most of normalized mean bias (NMB) within +/- 20%. The model reproduced 53.3% of the observed hourly O3 within a factor of 1.5 with NMB of 29.7% and normalized mean error of 46.9% at the 342 AQS sites. The comparison of modeled and observed lidar O3 vertical profiles shows that whereas the model reproduced the observed vertical structure, it tended to overestimate at higher altitude. The model reproduced 64-77% of observed NO2 photolysis rate values within a factor of 1.5 at the AIRMAP sites. At the HF site, comparison of modeled and observed O3/nitrogen oxide (NOx) ratios suggests that the site is mainly under strongly NOx-sensitive conditions (>53%). It was found that the modeled lower limits of the O3 production efficiency values (inferred from O3-CO correlation) are close to the observations.

In-situ Measurements of Ozone Production Rates and Comparisons to Model-derived Production Rates During the Houston, TX and Denver, CO DISCOVER-AQ Campaigns

NASA Astrophysics Data System (ADS)

Baier, B. C.; Brune, W. H.; Miller, D. O.; Lefer, B. L.

2015-12-01

Tropospheric ozone (O3) is a secondary pollutant that has harmful effects on human and plant life. The climate and urban emissions in Houston, TX and Denver, CO can be conducive for significant ozone production and thus, high ozone events. Tighter government strategies for ozone mitigation have been proposed, which involve reducing the current EPA eight-hour ozone standard from 75 ppb to 65-70 ppb. These strategies rely on the reduction of ozone precursors in order to decrease the ozone production rate, P(O3). The changes in the ozone concentration at a certain location are dependent upon P(O3), so decreasing P(O3) can decrease ozone levels provided that it has not been transported from other areas. Air quality models test reduction strategies before they are implemented, locate ozone sources, and predict ozone episodes. Traditionally, P(O3) has been calculated by models. However, large uncertainties in model emissions inventories, chemical mechanisms, and meteorology can reduce confidence in this approach. A new instrument, the Measurement of Ozone Production Sensor (MOPS) directly measures P(O3) and can provide an alternate approach to determining P(O3). An updated version of the Penn State MOPS (MOPSv2.0) was deployed to Houston, TX and Denver, CO as a part of NASA's DISCOVER-AQ field campaign in the summers of 2013 and 2014, respectively. We present MOPS directly-measured P(O3) rates from these areas, as well as comparisons to zero-dimensional and three-dimensional modeled P(O3) using the RACM2 and MCMv2.2 mechanisms. These comparisons demonstrate the potential of the MOPS to test and evaluate model-derived P(O3), to advance the understanding of model chemical mechanisms, and to improve predictions of high ozone events.

Multitemporal Monitoring of the Air Quality in Bulgaria by Satellite Based Instruments

NASA Astrophysics Data System (ADS)

Nikolov, Hristo; Borisova, Denitsa

2015-04-01

Nowadays the effect on climate changes on the population and environment caused by air pollutants at local and regional scale by pollution concentrations higher than allowed is undisputable. Main sources of gas releases are due to anthropogenic emissions caused by the economic and domestic activities of the inhabitants, and to less extent having natural origin. Complementary to pollutants emissions the local weather parameters such as temperature, precipitation, wind speed, clouds, atmospheric water vapor, and wind direction control the chemical reactions in the atmosphere. It should be noted that intrinsic property of the air pollution is its "transboundary-ness" and this is why the air quality (AQ) is not affecting the population of one single country only. This why the exchange of information concerning AQ at EU level is subject to well established legislation and one of EU flagship initiatives for standardization in data exchange, namely INSPIRE, has to cope with. It should be noted that although good reporting mechanism with regard to AQ is already established between EU member states national networks suffer from a serious disadvantage - they don't form a regular grid which is a prerequisite for verification of pollutants transport modeling. Alternative sources of information for AQ are the satellite observations (i.e. OMI, TOMS instruments) providing daily data for ones of the major contributors to air pollution such as O3, NOX and SO2. Those data form regular grids and are processed the same day of the acquisition so they could be used in verification of the outputs generated by numerical modeling of the AQ and pollution transfer. In this research we present results on multitemporal monitoring of several regional "hot spots" responsible for greenhouse gases emissions in Bulgaria with emphasis on satellite-based instruments. Other output from this study is a method for validation of the AQ forecasts and also providing feedback to the service that prepares

DISCOVER-AQ: a unique acoustic propagation verification and validation data set

DOT National Transportation Integrated Search

2015-08-09

In 2013, the National Aeronautics and Space Administration conducted a month-long flight test for the Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality research effort in Houston...

TTI CM/AQ evaluation model user`s guide and workshop training materials. Interim research report, September 1993-August 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-08-01

The TTI CM/AQ Evaluation Model evaluates potential projects based on the following criteria: eligibility, travel impacts, emission impacts, and cost-effectiveness. To compare independent projects within a region during the decision process for CM/AQ funding, each project evaluated with this model is given an overall score based on the project`s effects for the criteria listed above. Training workshops were held by TTI in the first quarter of 1995 to teach metropolitan planning organization, state department of transportation, and regional air quality organization staff how to use this model. Basics of sketch-planning applications were also taught. The DRCOG and TTI CM/AQ Evaluationmore » Models represent significant steps toward the development of analytical methodologies for selecting projects for CM/AQ funding. Because the needs of nonattainment and attainment areas change over time, this model is particularly useful as key evaluation criteria can be modified to reflect the changing needs of a metropolitan area.« less

Development of On-line Wildfire Emissions for the Operational Canadian Air Quality Forecast System

NASA Astrophysics Data System (ADS)

Pavlovic, R.; Menard, S.; Chen, J.; Anselmo, D.; Paul-Andre, B.; Gravel, S.; Moran, M. D.; Davignon, D.

2013-12-01

An emissions processing system has been developed to incorporate near-real-time emissions from wildfires and large prescribed burns into Environment Canada's real-time GEM-MACH air quality (AQ) forecast system. Since the GEM-MACH forecast domain covers Canada and most of the USA, including Alaska, fire location information is needed for both of these large countries. Near-real-time satellite data are obtained and processed separately for the two countries for organizational reasons. Fire location and fuel consumption data for Canada are provided by the Canadian Forest Service's Canadian Wild Fire Information System (CWFIS) while fire location and emissions data for the U.S. are provided by the SMARTFIRE (Satellite Mapping Automated Reanalysis Tool for Fire Incident Reconciliation) system via the on-line BlueSky Gateway. During AQ model runs, emissions from individual fire sources are injected into elevated model layers based on plume-rise calculations and then transport and chemistry calculations are performed. This 'on the fly' approach to the insertion of emissions provides greater flexibility since on-line meteorology is used and reduces computational overhead in emission pre-processing. An experimental wildfire version of GEM-MACH was run in real-time mode for the summers of 2012 and 2013. 48-hour forecasts were generated every 12 hours (at 00 and 12 UTC). Noticeable improvements in the AQ forecasts for PM2.5 were seen in numerous regions where fire activity was high. Case studies evaluating model performance for specific regions, computed objective scores, and subjective evaluations by AQ forecasters will be included in this presentation. Using the lessons learned from the last two summers, Environment Canada will continue to work towards the goal of incorporating near-real-time intermittent wildfire emissions within the operational air quality forecast system.

Deciphering the role of radical precursors during the Second Texas Air Quality Study.

PubMed

Olaguer, Eduardo P; Rappenglück, Bernhard; Lefer, Barry; Stutz, Jochen; Dibb, Jack; Griffin, Robert; Brune, William H; Shauck, Maxwell; Buhr, Martin; Jeffries, Harvey; Vizuete, William; Pinto, Joseph P

2009-11-01

The Texas Environmental Research Consortium (TERC) funded significant components of the Second Texas Air Quality Study (TexAQS II), including the TexAQS II Radical and Aerosol Measurement Project (TRAMP) and instrumented flights by a Piper Aztec aircraft. These experiments called attention to the role of short-lived radical sources such as formaldehyde (HCHO) and nitrous acid (HONO) in increasing ozone productivity. TRAMP instruments recorded daytime HCHO pulses as large as 32 parts per billion (ppb) originating from upwind industrial activities in the Houston Ship Channel, where in situ surface monitors detected HCHO peaks as large as 52 ppb. Moreover, Ship Channel petrochemical flares were observed to produce plumes of apparent primary HCHO. In one such combustion plume that was depleted of ozone by large emissions of oxides of nitrogen (NOx), the Piper Aztec measured a ratio of HCHO to carbon monoxide (CO) 3 times that of mobile sources. HCHO from uncounted primary sources or ozonolysis of underestimated olefin emissions could significantly increase ozone productivity in Houston beyond previous expectations. Simulations with the CAMx model show that additional emissions of HCHO from industrial flares or mobile sources can increase peak ozone in Houston by up to 30 ppb. Other findings from TexAQS II include significant concentrations of HONO throughout the day, well in excess of current air quality model predictions, with large nocturnal vertical gradients indicating a surface or near-surface source of HONO, and large concentrations of nighttime radicals (approximately30 parts per trillion [ppt] HO2). HONO may be formed heterogeneously on urban canopy or particulate matter surfaces and may be enhanced by organic aerosol of industrial or motor vehicular origin, such as through conversion of nitric acid (HNO3). Additional HONO sources may increase daytime ozone by more than 10 ppb. Improving the representation of primary and secondary HCHO and HONO in air quality

77 FR 21663 - Air Quality Implementation Plans; Kentucky; Attainment Plan for the Kentucky Portion of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-11

... available, but not yet certified, in the Air Quality System (AQS) database for 2011 show that this Area.... Moreover, there is no support for the Commenter's contention, based on the flawed premise that allowance... strong legal basis. To the extent that the current status of CAIR and the Transport Rule affect any of...

77 FR 21690 - Approval and Promulgation of Air Quality Implementation Plan for 1997 8-Hour Ozone Standard; Arizona

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-11

... and emissions input data preparation, model performance evaluation, interpreting modeling results, and... standard based on ambient ozone monitoring data for the 2006- 2008 period. EPA has not yet acted on this... ppm) and years thereafter were at or below the standard. See EPA Air Quality System (AQS) data...

The physico-chemical evolution of atmospheric aerosols and the gas-particle partitioning of inorganic aerosol during KORUS-AQ

NASA Astrophysics Data System (ADS)

Lee, T.; Park, T.; Lee, J. B.; Lim, Y. J.; Ahn, J.; Park, J. S.; Soo, C. J.; Desyaterik, Y.; Collett, J. L., Jr.

2017-12-01

Aerosols influence climate change directly by scattering and absorption and indirectly by acting as cloud condensation nuclei and some of the effects of aerosols are reduction in visibility, deterioration of human health, and deposition of pollutants to ecosystems. Urban area is large source of aerosols and aerosol precursors. Aerosol sources are both local and from long-range transport. Long-range transport processed aerosol are often dominant sources of aerosol pollution in Korea. To improve our knowledge of aerosol chemistry, Korea and U.S-Air Quality (KORUS-AQ) of Aircraft-based aerosol measurement took place in and around Seoul, Korea during May and June 2016. KORUS-AQ campaigns were conducted to study the chemical characterization and processes of pollutants in the Seoul Metropolitan area to regional scales of Korean peninsula. Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed on aircraft platforms on-board DC-8 (NASA) aircraft. We characterized aerosol chemical properties and mass concentrations of sulfate, nitrate, ammonium and organics in polluted air plumes and investigate the spatial and vertical distribution of the species. The results of studies show that organics is predominant in Aerosol and a significant fraction of the organics is oxygenated organic aerosol (OOA) at the high altitude. Both Nitrate and sulfate can partition between the gas and particle phases. The ratios for HNO3/(N(V) (=gaseous HNO3 + particulate Nitrate) and SO2/(SO2+Sulfate) were found to exhibit quite different distributions between the particles and gas phase for the locations during KORUS-AQ campaign, representing potential for formation of additional particulate nitrate and sulfate. The results of those studies can provide highly resolved temporal and spatial air pollutant, which are valuable for air quality model input parameters for aerosol behaviour.

New directions: Time for a new approach to modeling surface-atmosphere exchanges in air quality models?

NASA Astrophysics Data System (ADS)

Saylor, Rick D.; Hicks, Bruce B.

2016-03-01

Just as the exchange of heat, moisture and momentum between the Earth's surface and the atmosphere are critical components of meteorological and climate models, the surface-atmosphere exchange of many trace gases and aerosol particles is a vitally important process in air quality (AQ) models. Current state-of-the-art AQ models treat the emission and deposition of most gases and particles as separate model parameterizations, even though evidence has accumulated over time that the emission and deposition processes of many constituents are often two sides of the same coin, with the upward (emission) or downward (deposition) flux over a landscape depending on a range of environmental, seasonal and biological variables. In this note we argue that the time has come to integrate the treatment of these processes in AQ models to provide biological, physical and chemical consistency and improved predictions of trace gases and particles.

Ozone production by corona discharges during a convective event in DISCOVER-AQ Houston

NASA Astrophysics Data System (ADS)

Kotsakis, Alexander; Morris, Gary A.; Lefer, Barry; Jeon, Wonbae; Roy, Anirban; Minschwaner, Ken; Thompson, Anne M.; Choi, Yunsoo

2017-07-01

An ozonesonde launched near electrically active convection in Houston, TX on 5 September 2013 during the NASA DISCOVER-AQ project measured a large enhancement of ozone throughout the troposphere. A separate ozonesonde was launched from Smith Point, TX (∼58 km southeast of the Houston site) at approximately the same time as the launch from Houston and did not measure that enhancement. Furthermore, ozone profiles for the descent of both sondes agreed well with the ascending Smith Point profile, suggesting a highly localized event in both space and time in which an anomalously large enhancement of 70-100 ppbv appeared in the ascending Houston ozonesonde data. Compared to literature values, such an enhancement appears to be the largest observed to date. Potential sources of the localized ozone enhancement such as entrainment of urban or biomass burning emissions, downward transport from the stratosphere, photochemical production from lightning NOx, and direct ozone production from corona discharges were investigated using model simulations. We conclude that the most likely explanation for the large ozone enhancement is direct ozone production by corona discharges. Integrating the enhancement seen in the Houston ozone profile and using the number of electrical discharges detected by the NLDN (or HLMA), we estimate a production of 2.48 × 1028 molecules of ozone per flash which falls within the range of previously recorded values (9.89 × 1026-9.82 × 1028 molecules of ozone per flash). Since there is currently no parameterization for the direct production of ozone from corona discharges we propose the implementation of an equation into a chemical transport model. Ultimately, additional work is needed to further understand the occurrence and impact of corona discharges on tropospheric chemistry on short and long timescales.

Ozone Production by Corona Discharges During a Convective Event in DISCOVER-AQ Houston

NASA Technical Reports Server (NTRS)

Kotsakis, Alexander; Morris, Gary A.; Lefer, Barry; Jeon, Wongbae; Roy, Anirban; Minschwaner, Ken; Thompson, Anne M.; Choi, Yunsoo

2017-01-01

An ozonesonde launched near electrically active convection in Houston, TX on 5 September 2013 during the NASA DISCOVER-AQ project measured a large enhancement of ozone throughout the troposphere. A separate ozonesonde was launched from Smith Point, TX (approx. 58 km southeast of the Houston site) at approximately the same time as the launch from Houston and did not measure that enhancement. Furthermore, ozone profiles for the descent of both sondes agreed well with the ascending Smith Point profile, suggesting a highly localized event in both space and time in which an anomalously large enhancement of 70 - 100 ppbv appeared in the ascending Houston ozonesonde data. Compared to literature values, such an enhancement appears to be the largest observed to date. Potential sources of the localized ozone enhancement such as entrainment of urban or biomass burning emissions, downward transport from the stratosphere, photochemical production from lightning NO(sub x), and direct ozone production from corona discharges were investigated using model simulations. We conclude that the most likely explanation for the large ozone enhancement is direct ozone production by corona discharges. Integrating the enhancement seen in the Houston ozone profile and using the number of electrical discharges detected by the NLDN (or HLMA), we estimate a production of 2.48 x 10(exp. 28) molecules of ozone per flash which falls within the range of previously recorded values (9.89 x 10(exp. 26) - 9.82 x 10)exp. 28) molecules of ozone per flash). Since there is currently no parameterization for the direct production of ozone from corona discharges we propose the implementation of an equation into a chemical transport model. Ultimately, additional work is needed to further understand the occurrence and impact of corona discharges on tropospheric chemistry on short and long timescales.

Quantifying a Relationship between Place-Based Learning and Environmental Quality

ERIC Educational Resources Information Center

Johnson, Brian; Duffin, Michael; Murphy, Michael

2012-01-01

The goal of this study was to investigate the degree to which school-based and nonformal education programs that focus on air quality (AQ) achieved measurable AQ improvements, and whether specific instructional methods were associated with those improvements. We completed a standardized telephone interview with representatives of 54 AQ education…

An Elevated Reservoir of Air Pollutants over the Mid-Atlantic States During the 2011 DISCOVER-AQ Campaign: Airborne Measurements and Numerical Simulations

NASA Technical Reports Server (NTRS)

He, Hao; Loughner, Christopher P.; Stehr, Jeffrey W.; Arkinson, Heather L.; Brent, Lacey C.; Follette-Cook, Melanie B.; Tzortziou, Maria A.; Pickering, Kenneth E.; Thompson, Anne M.; Martins, Douglas K.;

Projection of Changes in Regional Climate and Air Quality in the Great Lakes Basin between 2000 and 2050 for the RCP8.5 Emissions Scenario using the GEM-AQ Model

NASA Astrophysics Data System (ADS)

Lupu, A.; Semeniuk, K.; McConnell, J. C.; Kaminski, J. W.; Toyota, K.; Neary, L.

2012-12-01

The Global Environmental Multiscale Air Quality (GEM-AQ) model was run in global and limited area model (LAM) modes for the baseline year 2000 and one future year, 2050, on three different horizontal grids of increasing resolution from global (1.5°) to North American (LAM, 0.45°) to Ontario regional scale (LAM, 0.15°). For the future simulation we used the high greenhouse emissions scenario RCP8.5. Boundary conditions for the LAM runs were taken from the coarser resolution runs. All simulations had 54 vertical sigma-pressure hybrid levels from the ground to the stratopause (˜50 km), which should give a good representation of ozone injection to the troposphere from the stratosphere. The model uses the interactive land surface scheme ISBA. Sea surface and lake temperatures are prescribed, but ice cover is partially interactive based on prescribed fields. A lake model, FLAKE, was coupled to GEM-AQ in order to capture the impacts of the Great Lakes on the meteorology when the model is run at high resolution. For the Ontario regional simulation the interactive lake model allowed for self-consistent water temperatures and moisture fluxes. The simulation for the year 2000 shows that the model is able to reproduce the observed monthly surface temperatures across the US. The monthly surface ozone is reproduced at the level of detail of most other air quality models with year 2000 weather as opposed to a free run forced by SSTs. Our year 2050 simulation shows that ozone levels during the summer throughout most of Ontario and Canada will increase. Regions south of the latitude of Lake Superior will generally see decreased levels of summer (JJA) ozone, except for around large urban areas such as Toronto, Chicago and Montreal. However, NOx levels will decrease during the summer, reflecting decreased emissions. Ozone levels in the US will generally improve. Other indices rather than simple averages yield a different perspective. If the MDA8 ozone metric and NO2 one-hour 98th

The National Emissions Inventory Significantly Overestimates NOx Emissions: Analysis of CMAQ and in situ observations from DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Anderson, D. C.; Dickerson, R. R.; Loughner, C.

2013-12-01

NOx and CO not only adversely impact human health, but they, along with associated VOCs, are also important precursors for O3 formation. While ambient NOx and CO concentrations have decreased dramatically over the past 10-20 years, O3 has remained a more recalcitrant problem, particularly in the Baltimore/Washington region. Reduction of O3 production requires that emissions inventories, such as the National Emissions Inventory (NEI), accurately capture total emissions of CO and NOx while also correctly apportioning them among different sectors. Previous evaluations of the NEI paint different pictures of its accuracy, with assertions that it overestimates either one or both of CO and NOx from anywhere between 25 percent to a factor of 2. These conflicting claims warrant further investigation. In this study, measurements of NOx and CO taken aboard the NOAA P3B airplane during the 2011 DISCOVER-AQ field campaign were used to determine the NOx/CO emissions ratio at 6 locations in the Washington/Baltimore region. An average molar emissions ratio of 12.8 × 1.2 CO/NOx was found by calculating the change in CO over the change in NOx from vertical concentration profiles in the planetary boundary layer. Ratios showed little variation with location. Observed values were approximately a factor of 1.35 - 1.75 times greater than that predicted by the annual, countywide emissions ratio from the 2008 NEI. When compared to a temporalized, gridded version of the inventory processed by SMOKE, ratio observations were greater than that predicted by inventories by up to a factor of 2. Comparison of the in situ measurements and remotely sensed observations from MOPITT of CO to the Community Multiscale Air Quality (CMAQ) model agree within 10-35 percent, with the model higher on average. Measurements of NOy by two separate analytical techniques, on the other hand, show that CMAQ consistently and significantly overestimates NOy concentrations. Combined with the CO observations, this

Chemical data assimilation of geostationary aerosol optical depth and PM surface observations on regional aerosol modeling over the Korean Peninsula during KORUS-AQ campaign

NASA Astrophysics Data System (ADS)

Jung, J.; Choi, Y.; Souri, A.; Jeon, W.

2017-12-01

Particle matter(PM) has played a significantly deleterious role in affecting human health and climate. Recently, continuous high concentrations of PM in Korea attracted public attention to this critical issue, and the Korea-United States Air Quality Study(KORUS-AQ) campaign in 2016 was conducted to investigate the causes. For this study, we adjusted the initial conditions in the chemical transport model(CTM) to improve its performance over Korean Peninsula during KORUS-AQ period, using the campaign data to evaluate our model performance. We used the Optimal Interpolation(OI) approach and used hourly surface air quality measurement data from the Air Quality Monitoring Station(AQMS) by NIER and the aerosol optical depth(AOD) measured by a GOCI sensor from the geostationary orbit onboard the Communication Ocean and Meteorological Satellite(COMS). The AOD at 550nm has a 6km spatial resolution and broad coverage over East Asia. After assimilating the surface air quality observation data, the model accuracy significantly improved compared to base model result (without assimilation). It reported very high correlation value (0.98) and considerably decreased mean bias. Especially, it well captured some high peaks which was underpredicted by the base model. To assimilate satellite data, we applied AOD scaling factors to quantify each specie's contribution to total PM concentration and find-mode fraction(FMF) to define vertical distribution. Finally, the improvement showed fairly good agreement.

NASA Tropospheric Composition Program field campagins as prototypes to advance the Integrated Observing System for Air Quality

NASA Astrophysics Data System (ADS)

Lefer, B. L.; Crawford, J. H.; Pierce, R. B.; Berkoff, T.; Swap, R.; Janz, S. J.; Ahn, J.; Al-Saadi, J. A.

2017-12-01

With the launch over the virtual constellation of earth observing satellites for atmospheric composition (e.g., TROPOMI, GEMS, TEMPO, and Sentinel-4) over the next several years, we have a unique opportunity to develop an Integrated Observing System (IOS) for air quality in the northern hemisphere. Recently, NASA's Tropospheric Composition Program (TCP) has participated in several different air quality related field campaigns as an effort to explore various prototypes of the IOS for Air Quality. The IOS for air quality could be a system were space-based observations of air quality (generally, column abundances of NO2, HCHO, O3, SO2, and AOD) are given added "value" by being integrated with: a) long-term ground-based observations;b) regional and global air quality and chemical transport models; as well as c) measurements from targeted airborne field campaigns. The recent Korea-US Air Quality Study (KORUS-AQ), the Lake Michigan Ozone Study 2017 (LMOS), and the Ozone Water-Land Environmental Transition Study (OWLETS) field campaigns were held in different locations and made measurements over different scale. However, all of these provide an opportunity to learn about how a future integrated air quality observing system can be implemented to serve a variety of air quality related objectives. NASA TCP is also exploring enchancements to our routine observations to strengthen the IOS for air quality in the future.

Atmospheric CH₄ and N₂O measurements near Greater Houston area landfills using a QCL-based QEPAS sensor system during DISCOVER-AQ 2013.

PubMed

Jahjah, Mohammad; Jiang, Wenzhe; Sanchez, Nancy P; Ren, Wei; Patimisco, Pietro; Spagnolo, Vincenzo; Herndon, Scott C; Griffin, Robert J; Tittel, Frank K

2014-02-15

A quartz-enhanced photoacoustic absorption spectroscopy (QEPAS)-based gas sensor was developed for methane (CH₄) and nitrous-oxide (N₂O) detection. The QEPAS-based sensor was installed in a mobile laboratory operated by Aerodyne Research, Inc. to perform atmospheric CH₄ and N₂O detection around two urban waste-disposal sites located in the northeastern part of the Greater Houston area, during DISCOVER-AQ, a NASA Earth Venture during September 2013. A continuous wave, thermoelectrically cooled, 158 mW distributed feedback quantum cascade laser emitting at 7.83 μm was used as the excitation source in the QEPAS gas sensor system. Compared to typical ambient atmospheric mixing ratios of CH₄ and N₂O of 1.8 ppmv and 323 ppbv, respectively, significant increases in mixing ratios were observed when the mobile laboratory was circling two waste-disposal sites in Harris County and when waste disposal trucks were encountered.

Characterization of the genome of the dairy Lactobacillus helveticus bacteriophage {Phi}AQ113.

PubMed

Zago, Miriam; Scaltriti, Erika; Rossetti, Lia; Guffanti, Alessandro; Armiento, Angelarita; Fornasari, Maria Emanuela; Grolli, Stefano; Carminati, Domenico; Brini, Elena; Pavan, Paolo; Felsani, Armando; D'Urzo, Annalisa; Moles, Anna; Claude, Jean-Baptiste; Grandori, Rita; Ramoni, Roberto; Giraffa, Giorgio

2013-08-01

The complete genomic sequence of the dairy Lactobacillus helveticus bacteriophage ΦAQ113 was determined. Phage ΦAQ113 is a Myoviridae bacteriophage with an isometric capsid and a contractile tail. The final assembled consensus sequence revealed a linear, circularly permuted, double-stranded DNA genome with a size of 36,566 bp and a G+C content of 37%. Fifty-six open reading frames (ORFs) were predicted, and a putative function was assigned to approximately 90% of them. The ΦAQ113 genome shows functionally related genes clustered together in a genome structure composed of modules for DNA replication/regulation, DNA packaging, head and tail morphogenesis, cell lysis, and lysogeny. The identification of genes involved in the establishment of lysogeny indicates that it may have originated as a temperate phage, even if it was isolated from natural cheese whey starters as a virulent phage, because it is able to propagate in a sensitive host strain. Additionally, we discovered that the ΦAQ113 phage genome is closely related to Lactobacillus gasseri phage KC5a and Lactobacillus johnsonii phage Lj771 genomes. The phylogenetic similarities between L. helveticus phage ΦAQ113 and two phages that belong to gut species confirm a possible common ancestral origin and support the increasing consideration of L. helveticus as a health-promoting organism.

Characterization of the Genome of the Dairy Lactobacillus helveticus Bacteriophage ΦAQ113

PubMed Central

Scaltriti, Erika; Rossetti, Lia; Guffanti, Alessandro; Armiento, Angelarita; Fornasari, Maria Emanuela; Grolli, Stefano; Carminati, Domenico; Brini, Elena; Pavan, Paolo; Felsani, Armando; D'Urzo, Annalisa; Moles, Anna; Claude, Jean-Baptiste; Grandori, Rita; Ramoni, Roberto; Giraffa, Giorgio

2013-01-01

The complete genomic sequence of the dairy Lactobacillus helveticus bacteriophage ΦAQ113 was determined. Phage ΦAQ113 is a Myoviridae bacteriophage with an isometric capsid and a contractile tail. The final assembled consensus sequence revealed a linear, circularly permuted, double-stranded DNA genome with a size of 36,566 bp and a G+C content of 37%. Fifty-six open reading frames (ORFs) were predicted, and a putative function was assigned to approximately 90% of them. The ΦAQ113 genome shows functionally related genes clustered together in a genome structure composed of modules for DNA replication/regulation, DNA packaging, head and tail morphogenesis, cell lysis, and lysogeny. The identification of genes involved in the establishment of lysogeny indicates that it may have originated as a temperate phage, even if it was isolated from natural cheese whey starters as a virulent phage, because it is able to propagate in a sensitive host strain. Additionally, we discovered that the ΦAQ113 phage genome is closely related to Lactobacillus gasseri phage KC5a and Lactobacillus johnsonii phage Lj771 genomes. The phylogenetic similarities between L. helveticus phage ΦAQ113 and two phages that belong to gut species confirm a possible common ancestral origin and support the increasing consideration of L. helveticus as a health-promoting organism. PMID:23728811

Modeling the Dynamic Change of Air Quality and its Response to Emission Trends

NASA Astrophysics Data System (ADS)

Zhou, Wei

This thesis focuses on evaluating atmospheric chemistry and transport models' capability in simulating the chemistry and dynamics of power plant plumes, evaluating their strengths and weaknesses in predicting air quality trends at regional scales, and exploring air quality trends in an urban area. First, the Community Mutlti-scale Air Quality (CMAQ) model is applied to simulate the physical and chemical evolution of power plant plumes (PPPs) during the second Texas Air Quality Study (TexAQS) in 2006. SO2 and NOy were observed to be rapidly removed from PPPs on cloudy days but not on cloud-free days, indicating efficient aqueous processing of these compounds in clouds, while the model fails to capture the rapid loss of SO2 and NOy in some plumes on the cloudy day. Adjustments to cloud liquid water content (QC) and the default metal concentrations in the cloud module could explain some of the SO 2 loss while NOy in the model was insensitive to QC. Second, CMAQ is applied to simulate the ozone (O3) change after the NO x SIP Call and mobile emission controls in the eastern U.S. from 2002 to 2006. Observed downward changes in 8-hour O3 concentrations in the NOx SIP Call region were under-predicted by 26%--66%. The under-prediction in O3 improvements could be alleviated by 5%--31% by constraining NOx emissions in each year based on observed NOx concentrations while temperature biases or uncertainties in chemical reactions had minor impact on simulated O3 trends. Third, changes in ozone production in the Houston area is assessed with airborne measurements from TexAQS 2000 and 2006. Simultaneous declines in nitrogen oxides (NOx=NO+NO2) and highly reactive Volatile Organic Compounds (HRVOCs) were observed in the Houston Ship Channel (HSC). The reduction in HRVOCs led to the decline in total radical concentration by 20-50%. Rapid ozone production rates in the Houston area declined by 40-50% from 2000 to 2006, to which the reduction in NOx and HRVOCs had the similar

Modelling and analysis of ozone concentration by artificial intelligent techniques for estimating air quality

NASA Astrophysics Data System (ADS)

Taylan, Osman

2017-02-01

High ozone concentration is an important cause of air pollution mainly due to its role in the greenhouse gas emission. Ozone is produced by photochemical processes which contain nitrogen oxides and volatile organic compounds in the lower atmospheric level. Therefore, monitoring and controlling the quality of air in the urban environment is very important due to the public health care. However, air quality prediction is a highly complex and non-linear process; usually several attributes have to be considered. Artificial intelligent (AI) techniques can be employed to monitor and evaluate the ozone concentration level. The aim of this study is to develop an Adaptive Neuro-Fuzzy inference approach (ANFIS) to determine the influence of peripheral factors on air quality and pollution which is an arising problem due to ozone level in Jeddah city. The concentration of ozone level was considered as a factor to predict the Air Quality (AQ) under the atmospheric conditions. Using Air Quality Standards of Saudi Arabia, ozone concentration level was modelled by employing certain factors such as; nitrogen oxide (NOx), atmospheric pressure, temperature, and relative humidity. Hence, an ANFIS model was developed to observe the ozone concentration level and the model performance was assessed by testing data obtained from the monitoring stations established by the General Authority of Meteorology and Environment Protection of Kingdom of Saudi Arabia. The outcomes of ANFIS model were re-assessed by fuzzy quality charts using quality specification and control limits based on US-EPA air quality standards. The results of present study show that the ANFIS model is a comprehensive approach for the estimation and assessment of ozone level and is a reliable approach to produce more genuine outcomes.

Demonstration of a novel cavity ring down spectrometer for NO2 measurement during Discover AQ (July, 2011) where column profiles in the troposphere were collected over the mid Atlantic region of the United States

NASA Astrophysics Data System (ADS)

Brent, L. C.; Stehr, J. W.; Thorn, W.; Leen, J.; Gupta, M.; Luke, W. T.; Kelley, P.; Ren, X.; He, H.; Arkinson, H.; Weinheimer, A. J.; Pusede, S. E.; Cohen, R. C.; Dickerson, R. R.; Discover AQ science Team

2011-12-01

Real time, atmospheric NO2 column profiles from the Mid-Atlantic region, during the NASA Discover AQ air campaign, demonstrate that cavity ring down spectroscopy, with a LED light source, is a suitable technique for the detection NO2 in the boundary layer and lower free troposphere. Preliminary results from this air campaign indicate that 0.5 to 30 ppb of NO2 can be observed and that the results were similar to NO2 measurements obtained via laser induced fluorescence and chemiluminescence. The cavity ringdown instrument is relatively inexpensive, weighs 40 lbs, and relies on a built in zeroing method to account for drift with respect to time and altitude. Follow on collaboration with NOAA and NIST will consist of side by side ambient air comparison and calibration. In this field experiment the NOAA modified Thermo 42s which uses a UV light source to selectively convert NO2 to NO and chemiluminecsent detection, and a NIST Thermo 42I with a molybdenum NO2 to NO converter and chemiluminescent detection will be compared to NO2 measured by the Los Gatos Research cavity ringdown detector. Part of the calibration procedure will include testing for interferences of nitric acid, n-propyl nitrate and HONO. The altitude integral of NO2 concentrations provide column content suitable for comparison to measurements made from space and for remotely sensing spectrometers. This data helps in the understanding of transport and is necessary for drawing policy relevant conclusions with respect to pollution control.

NEIGHBORHOOD SCALE MODELING OF PM 2.5 AND AIR TOXICS CONCENTRATION DISTRIBUTIONS TO DRIVE HUMAN EXPOSURE MODELS

EPA Science Inventory

Air quality (AQ) simulation models provide a basis for implementing the National Ambient Air Quality Standards (NAAQS) and are a tool for performing risk-based assessments and for developing environmental management strategies. Fine particulate matter (PM 2.5), its constituent...

Evaluation of the GEM-AQ air quality model during the Québec smoke event of 2002: Analysis of extensive and intensive optical disparities

NASA Astrophysics Data System (ADS)

O'Neill, N. T.; Campanelli, M.; Lupu, A.; Thulasiraman, S.; Reid, J. S.; Aubé, M.; Neary, L.; Kaminski, J. W.; McConnell, J. C.

The root-mean-square (rms) differences between the Canadian air quality model GEM-AQ and measurements for intensive and extensive optical variables (aerosol optical depth or AOD and Ångström exponent or α) were investigated using data from the July 2002 Québec smoke event. In order to quantify regional differences between model and measurements we employed a three component analysis of rms differences. The behaviour of the two absolute amplitude rms components of AOD (difference of the means and the difference of the standard deviations) enabled us to infer emission properties which would otherwise have been masked by the larger 'anti-correlation' component. We found the inferred emission fluxes to be significantly higher than the original geostationary, satellite-derived FLAMBÉ (fire locating and modelling of burning emissions) emissions flux estimates employed as inputs to the simulations. The model captured the regional decrease of the intensive α exponent (increase of particle size with trajectory time), while the agreement with the extensive AOD parameter was marginal but clearly dependent on the nature of the spatio-temporal statistical tools employed to characterize model performance. In establishing the α versus trajectory time trend, the modelled AOD data was filtered in the same way as the measured data (very large AODs are eliminated). This processing of modelled results was deemed necessary in order to render the α results comparable with the measurements; in the latter case it was difficult, if not impossible, to discriminate between measured α trends due to instrumental artifacts (non-linearities at low signal strength) versus trends due to coagulative effects.

Analysis of Air Toxics From NOAA WP-3 Aircraft Measurements During the TexAQS 2006 Campaign: Comparison With Emission Inventories and Additive Inhalation Risk Factors

NASA Astrophysics Data System (ADS)

Del Negro, L. A.; Warneke, C.; de Gouw, J. A.; Atlas, E.; Lueb, R.; Zhu, X.; Pope, L.; Schauffler, S.; Hendershot, R.; Washenfelder, R.; Fried, A.; Richter, D.; Walega, J. G.; Weibring, P.

2007-12-01

Benzene and nine other air toxics classified as human carcinogens by the International Agency for Research on Cancer (IARC) were measured from the NOAA WP-3 aircraft during the TexAQS 2006 campaign. In-situ measurements of benzene, measured with a PTR-MS instrument, are used to estimate emission fluxes for comparison with point source emission inventories developed by the Texas Commission on Environmental Quality. Mean and median mixing ratios for benzene, acetaldehyde, formaldehyde, 1,3-butadiene, carbon tetrachloride, chloroform, 1,2-dichloroethane, dibromoethane, dichloromethane, and vinyl chloride, encountered over the city of Houston during the campaign, are combined with inhalation unit risk factor values developed by the California Environmental Protection Agency and the United States Environmental Protection Agency to estimate the additive inhalation risk factor. This additive risk factor represents the risk associated with lifetime (70 year) exposure at the levels measured and should not be used as an absolute indicator of risk to individuals. However, the results are useful for assessments of changing relative risk over time, and for identifying dominant contributions to the overall air toxic risk.

Air pollution, athletic health and performance at the Olympic Games.

PubMed

Fitch, Ken

2016-01-01

The objective of this study was to briefly review air pollution and its effects on athletes' health and performance and to examine air quality (AQ) at specific Olympic Summer Games between 1964 and 2008. It will focus on any attempts made by the cities hosting these Olympics to improve AQ for the Games and if undertaken, how successful these were. The author had a medical role at five of the seven Olympic Games that will be examined and hence has personal experiences. Information was obtained from the readily accessible official reports of the Olympic Games, relevant published papers and books and the internet. For each of these seven Olympic Games, monitoring AQ was far below current acceptable standards and for the majority, minimal or no data on major pollutants was available. From what can be ascertained, at these Games, AQ varied but was less than optimal in most if not all. Nevertheless, there were few reported or known unfavorable effects on the health of Olympic athletes. To date, there have been few reported consequences of sub-optimal AQ at Olympic Games. The focus on AQ at Olympic Games has gradually increased over the past five decades and is expected to continue into the future.

Pragmatic estimation of a spatio-temporal air quality model with irregular monitoring data

NASA Astrophysics Data System (ADS)

Sampson, Paul D.; Szpiro, Adam A.; Sheppard, Lianne; Lindström, Johan; Kaufman, Joel D.

2011-11-01

Statistical analyses of health effects of air pollution have increasingly used GIS-based covariates for prediction of ambient air quality in "land use" regression models. More recently these spatial regression models have accounted for spatial correlation structure in combining monitoring data with land use covariates. We present a flexible spatio-temporal modeling framework and pragmatic, multi-step estimation procedure that accommodates essentially arbitrary patterns of missing data with respect to an ideally complete space by time matrix of observations on a network of monitoring sites. The methodology incorporates a model for smooth temporal trends with coefficients varying in space according to Partial Least Squares regressions on a large set of geographic covariates and nonstationary modeling of spatio-temporal residuals from these regressions. This work was developed to provide spatial point predictions of PM 2.5 concentrations for the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air) using irregular monitoring data derived from the AQS regulatory monitoring network and supplemental short-time scale monitoring campaigns conducted to better predict intra-urban variation in air quality. We demonstrate the interpretation and accuracy of this methodology in modeling data from 2000 through 2006 in six U.S. metropolitan areas and establish a basis for likelihood-based estimation.

Effects of local meteorology and aerosols on ozone and nitrogen dioxide retrievals from OMI and pandora spectrometers in Maryland, USA during DISCOVER-AQ 2011.

PubMed

Reed, Andra J; Thompson, Anne M; Kollonige, Debra E; Martins, Douglas K; Tzortziou, Maria A; Herman, Jay R; Berkoff, Timothy A; Abuhassan, Nader K; Cede, Alexander

An analysis is presented for both ground- and satellite-based retrievals of total column ozone and nitrogen dioxide levels from the Washington, D.C., and Baltimore, Maryland, metropolitan area during the NASA-sponsored July 2011 campaign of D eriving I nformation on S urface CO nditions from Column and VER tically Resolved Observations Relevant to A ir Q uality (DISCOVER-AQ). Satellite retrievals of total column ozone and nitrogen dioxide from the Ozone Monitoring Instrument (OMI) on the Aura satellite are used, while Pandora spectrometers provide total column ozone and nitrogen dioxide amounts from the ground. We found that OMI and Pandora agree well (residuals within ±25 % for nitrogen dioxide, and ±4.5 % for ozone) for a majority of coincident observations during July 2011. Comparisons with surface nitrogen dioxide from a Teledyne API 200 EU NO x Analyzer showed nitrogen dioxide diurnal variability that was consistent with measurements by Pandora. However, the wide OMI field of view, clouds, and aerosols affected retrievals on certain days, resulting in differences between Pandora and OMI of up to ±65 % for total column nitrogen dioxide, and ±23 % for total column ozone. As expected, significant cloud cover (cloud fraction >0.2) was the most important parameter affecting comparisons of ozone retrievals; however, small, passing cumulus clouds that do not coincide with a high (>0.2) cloud fraction, or low aerosol layers which cause significant backscatter near the ground affected the comparisons of total column nitrogen dioxide retrievals. Our results will impact post-processing satellite retrieval algorithms and quality control procedures.

Spatial surveys of CH4 emissions with a mobile multi-gas sensing platform during DISCOVER-AQ and CAREBEIJING-NCP field campaigns

NASA Astrophysics Data System (ADS)

Tao, L.; Sun, K.; Miller, D. J.; Zhu, T.; Zondlo, M. A.

2013-12-01

Methane (CH4) is the second most important greenhouse gas, which has a greenhouse warming potential 25 times that of carbon dioxide (CO2) on a per molecule basis and century timescale. Since pre-industrial times, the atmospheric concentration of CH4 has increased by 150% and contributes significantly to global warming. CH4 emits from a wide range of both anthropogenic and natural sources, which make the CH4 emission measurements difficult. As a result, there is still a large uncertainty in the partitioning of estimated CH4 emissions. Mobile platforms have been used and demonstrated as an effective tool to map the CH4 emissions and provide a large spatial coverage over cities and localized rural sources. However, the information we can get is very limited based on the measured atmospheric CH4 concentrations solely, due to the complexity of the various CH4 sources and limited time resolution. We have developed a mobile multi-gas open-path laser-based sensing platform that performs high resolution (5 Hz), in-situ and simultaneous measurements of NH3, CH4, CO2, N2O, CO and H2O. The combination of six important trace gases helps to understand the characteristics of different CH4 sources and identify them. With this mobile platform, we have participated and perform spatial surveys in two field campaigns: DISCOVER-AQ in California and CAREBEIJING-NCP in China. During the DISCOVER-AQ campaigns, our mobile platform has covered around 4300 km (81 hours) in winter 2013 including agricultural regions in San Joaquin Valley and multiple cities urban areas along the coast. In the CAREBEIJING-NCP campaign, a survey along 3300 km (61 hours) of roadway in Beijing and its surrounding North China Plain has been conducted in June, 2013. A wide variety of CH4 emission sources have been identified and measured, such as livestock farming, oil/gas drilling, wastewater treatment, landfill, biomass burning and motor vehicles (include liquefied nature gas (LNG) vehicles). For example, the

Air Quality Modeling | Air Quality Planning & Standards | US ...

EPA Pesticide Factsheets

2016-06-08

The basic mission of the Office of Air Quality Planning and Standards is to preserve and improve the quality of our nation's air. One facet of accomplishing this goal requires that new and existing air pollution sources be modeled for compliance with the National Ambient Air Quality Standards (NAAQS).

Evaluation of CMAQ and CAMx Ensemble Air Quality Forecasts during the 2015 MAPS-Seoul Field Campaign

NASA Astrophysics Data System (ADS)

Kim, E.; Kim, S.; Bae, C.; Kim, H. C.; Kim, B. U.

2015-12-01

The performance of Air quality forecasts during the 2015 MAPS-Seoul Field Campaign was evaluated. An forecast system has been operated to support the campaign's daily aircraft route decisions for airborne measurements to observe long-range transporting plume. We utilized two real-time ensemble systems based on the Weather Research and Forecasting (WRF)-Sparse Matrix Operator Kernel Emissions (SMOKE)-Comprehensive Air quality Model with extensions (CAMx) modeling framework and WRF-SMOKE- Community Multi_scale Air Quality (CMAQ) framework over northeastern Asia to simulate PM10 concentrations. Global Forecast System (GFS) from National Centers for Environmental Prediction (NCEP) was used to provide meteorological inputs for the forecasts. For an additional set of retrospective simulations, ERA Interim Reanalysis from European Centre for Medium-Range Weather Forecasts (ECMWF) was also utilized to access forecast uncertainties from the meteorological data used. Model Inter-Comparison Study for Asia (MICS-Asia) and National Institute of Environment Research (NIER) Clean Air Policy Support System (CAPSS) emission inventories are used for foreign and domestic emissions, respectively. In the study, we evaluate the CMAQ and CAMx model performance during the campaign by comparing the results to the airborne and surface measurements. Contributions of foreign and domestic emissions are estimated using a brute force method. Analyses on model performance and emissions will be utilized to improve air quality forecasts for the upcoming KORUS-AQ field campaign planned in 2016.

Effects of Grid Resolution on Modeled Air Pollutant Concentrations Due to Emissions from Large Point Sources: Case Study during KORUS-AQ 2016 Campaign

NASA Astrophysics Data System (ADS)

Ju, H.; Bae, C.; Kim, B. U.; Kim, H. C.; Kim, S.

2017-12-01

Large point sources in the Chungnam area received a nation-wide attention in South Korea because the area is located southwest of the Seoul Metropolitan Area whose population is over 22 million and the summertime prevalent winds in the area is northeastward. Therefore, emissions from the large point sources in the Chungnam area were one of the major observation targets during the KORUS-AQ 2016 including aircraft measurements. In general, horizontal grid resolutions of eulerian photochemical models have profound effects on estimated air pollutant concentrations. It is due to the formulation of grid models; that is, emissions in a grid cell will be assumed to be mixed well under planetary boundary layers regardless of grid cell sizes. In this study, we performed series of simulations with the Comprehensive Air Quality Model with eXetension (CAMx). For 9-km and 3-km simulations, we used meteorological fields obtained from the Weather Research and Forecast model while utilizing the "Flexi-nesting" option in the CAMx for the 1-km simulation. In "Flexi-nesting" mode, CAMx interpolates or assigns model inputs from the immediate parent grid. We compared modeled concentrations with ground observation data as well as aircraft measurements to quantify variations of model bias and error depending on horizontal grid resolutions.

Monitoring air quality in California's Central Valley with aircraft and continuous mountaintop observations - attribution insights gained by considering the scalar budget equation

NASA Astrophysics Data System (ADS)

Faloona, I. C.; Trousdell, J.; Caputi, D.; Conley, S. A.

2017-12-01

Ozone is one of the six criteria pollutants established by the US EPA's Clean Air Act, and one of two that still routinely violates federal standards as it is a secondary pollutant and therefore subject to indirect control strategies on complex, non-linear atmospheric chemistry. While improvements have been seen in many regions where ozone controls are in place, gains in California's San Joaquin Valley have lagged many other districts across the state. We present airborne measurements from several different campaigns in the valley (DISCOVER-AQ, ArvinO3, and CABOTS) along with data from a mountaintop monitoring site on its upwind side near the Pacific coast that has been operational for 5 years, and we shed light on several outstanding questions concerning air pollution in California's vast Central Valley. The framework of analysis is centered on the primitive equation of any atmospheric constituent - the scalar budget equation. By measuring each term in this equation, we gain insights into the relative impacts of exogenous (due to long range transport) vs. endogenous ozone (due to local photochemical production). We further argue that small aircraft campaigns with an emphasis on scalar budgeting sorties are a cost-effective tool in uncovering specific shortcomings of regional air quality models (e.g., lateral boundary conditions can be tested by comparing horizontal advection, turbulence parameterizations by comparing vertical fluxes, and chemical mechanisms by comparing net photochemical production rates.) In the case of NOx and CH4, for instance, we find that solving for surface emissions points toward inventory underestimates of both species by at least a factor of two. We discuss possible causes of these discrepancies, and suggest other ways to specifically vet aspects of regional air quality models with airborne measurements of meteorological and chemical variables.

Assessing the Association Between Asthma and Air Quality in the Presence of Wildfires

NASA Technical Reports Server (NTRS)

Young, L. J.; Lopiano, K. K.; Xu, X.; Holt, N. M.; Leary, E.; Al-Hamdan, M. Z.; Crosson, W. L.; Estes, M. G.; Luvall, J. C.; Estes, S. M.;

Iterative Inverse Modeling for Reconciliation of Emission Inventories during the 2006 TexAQS Intensive Field Campaign

NASA Astrophysics Data System (ADS)

Xiao, X.; Cohan, D. S.

2009-12-01

Substantial uncertainties in current emission inventories have been detected by the Texas Air Quality Study 2006 (TexAQS 2006) intensive field program. These emission uncertainties have caused large inaccuracies in model simulations of air quality and its responses to management strategies. To improve the quantitative understanding of the temporal, spatial, and categorized distributions of primary pollutant emissions by utilizing the corresponding measurements collected during TexAQS 2006, we implemented both the recursive Kalman filter and a batch matrix inversion 4-D data assimilation (FDDA) method in an iterative inverse modeling framework of the CMAQ-DDM model. Equipped with the decoupled direct method, CMAQ-DDM enables simultaneous calculation of the sensitivity coefficients of pollutant concentrations to emissions to be used in the inversions. Primary pollutant concentrations measured by the multiple platforms (TCEQ ground-based, NOAA WP-3D aircraft and Ronald H. Brown vessel, and UH Moody Tower) during TexAQS 2006 have been integrated for the use in the inverse modeling. Firstly pseudo-data analyses have been conducted to assess the two methods, taking a coarse spatial resolution emission inventory as a case. Model base case concentrations of isoprene and ozone at arbitrarily selected ground grid cells were perturbed to generate pseudo measurements with different assumed Gaussian uncertainties expressed by 1-sigma standard deviations. Single-species inversions have been conducted with both methods for isoprene and NOx surface emissions from eight states in the Southeastern United States by using the pseudo measurements of isoprene and ozone, respectively. Utilization of ozone pseudo data to invert for NOx emissions serves only for the purpose of method assessment. Both the Kalman filter and FDDA methods show good performance in tuning arbitrarily shifted a priori emissions to the base case “true” values within 3-4 iterations even for the nonlinear

Ozone production in remote oceanic and industrial areas derived from ship based measurements of peroxy radicals during TexAQS 2006

NASA Astrophysics Data System (ADS)

Sommariva, R.; Brown, S. S.; Roberts, J. M.; Brookes, D. M.; Parker, A. E.; Monks, P. S.; Bates, T. S.; Bon, D.; de Gouw, J. A.; Frost, G. J.; Gilman, J. B.; Goldan, P. D.; Herndon, S. C.; Kuster, W. C.; Lerner, B. M.; Osthoff, H. D.; Tucker, S. C.; Warneke, C.; Williams, E. J.; Zahniser, M. S.

2011-03-01

During the Texas Air Quality Study II (TexAQS 2006) campaign, a PEroxy Radical Chemical Amplifier (PERCA) was deployed on the NOAA research vessel R/V Brown to measure total peroxy radicals (HO2+Σ RO2). Day-time mixing ratios of HO2+Σ RO2 between 25 and 110 ppt were observed throughout the study area - the Houston/Galveston region and the Gulf coast of the US - and analyzed in relation to measurements of nitrogen oxides, volatile organic compounds (VOC) and photolysis rates to assess radical sources and sinks in the region. The measurements of HO2+Σ RO2 were used to calculate the in-situ net photochemical formation of ozone. Measured median values ranged from 0.6 ppb/h in clean oceanic air masses up to several tens of ppb/h in the most polluted industrial areas. The results are consistent with previous studies and generally agree with observations made during the previous TexAQS 2000 field campaign. The net photochemical ozone formation rates determined at Barbours Cut, a site immediately south of the Houston Ship Channel, were analyzed in relation to local wind direction and VOC reactivity to understand the relationship between ozone formation and local VOC emissions. The measurements of HO2+Σ RO2 made during the R/V Brown TexAQS 2006 cruise indicate that ozone formation is NOx-limited in the Houston/Galveston region and influenced by highly reactive hydrocarbons, especially alkenes from urban and industrial sources and their photo-oxidation products, such as formaldehyde.

Ozone production in remote oceanic and industrial areas derived from ship based measurements of peroxy radicals during TexAQS 2006

NASA Astrophysics Data System (ADS)

Sommariva, R.; Brown, S. S.; Roberts, J. M.; Brookes, D. M.; Parker, A. E.; Monks, P. S.; Bates, T. S.; Bon, D.; de Gouw, J. A.; Frost, G. J.; Gilman, J. B.; Goldan, P. D.; Herndon, S. C.; Kuster, W. C.; Lerner, B. M.; Osthoff, H. D.; Tucker, S. C.; Warneke, C.; Williams, E. J.; Zahniser, M. S.

2010-10-01

During the Texas Air Quality Study II (TexAQS 2006) campaign, a PEroxy Radical Chemical Amplifier (PERCA) was deployed on the NOAA research vessel R/V Brown to measure total peroxy radicals (HO2+ΣRO2). Day-time mixing ratios of HO2+ΣRO2 between 25 and 110 ppt were observed throughout the study area - the Houston/Galveston region and the Gulf coast of the U.S. - and analyzed in relation to measurements of nitrogen oxides, volatile organic compounds (VOC) and photolysis rates to assess radical sources and sinks in the region. The measurements of HO2+ΣRO2 were used to calculate the in-situ net photochemical formation of ozone. Measured median values ranged from 0.6 ppb/h in clean oceanic air masses up to several tens of ppb/h in the most polluted industrial areas. The results are consistent with previous studies and generally agree with observations made during the previous TexAQS 2000 field campaign. The net photochemical ozone formation rates determined at Barbours Cut, a site immediately south of the Houston Ship Channel, were analyzed in relation to local wind direction and VOC reactivity to understand the relationship between ozone formation and local VOC emissions. The measurements of HO2+ΣRO2 made during the R/V Brown TexAQS 2006 cruise indicate that ozone formation is NOx-limited in the Houston/Galveston region and influenced by highly reactive hydrocarbons, especially alkenes from urban and industrial sources and their photooxidation products, such as formaldehyde.

Measurements of Extensive Aerosol Optical Properties During TexAQS II: Implications for PM Compliance and Planning

NASA Astrophysics Data System (ADS)

Wright, M. E.; Atkinson, D. B.; Luke, W. T.

2007-12-01

In 2000, the Houston-Galveston Area (HGA) was designated as a non-attainment area for several criteria air pollutants by the US EPA. In order to meet the requirements of the federal Clean Air Act, the Second Texas Air Quality Study (TexAQS II) was designed to update the State Implementation Plan (SIP) by providing scientific air quality data over 18 months from June 2005 to October 2006. The data presented here was collected as part of the Texas Radical and Aerosol Measurement Program (TRAMP), a substudy of TexAQS II. Bulk aerosol optical properties were measured for six weeks atop the 60 m high Southwest Moody Tower on the University of Houston campus. The measurements were collected using a cavity ring-down transmissometer/nephelometer (CRDT/N) and consisted of the extensive aerosol coefficients: extinction (bext) at 532 and 1064 nm and scattering (bscat) at 530nm. In addition to daily and whole study averages and calculated mass values, positive correlations between the 1064 nm extinction and 532 nm absorption (babs = bext - bscat) values are displayed for this study period for the first time. Correlation between the particle scattering coefficient and the sum of AMS measured (UNH - PI: R. Griffin) sulfate and organic particle mass concentrations as well as covariance between optical properties and O3, CO and NOx values (ARL/NOAA - PI: W. Luke) are also examined. No correlation is expected between coarse particles (PM10), which are typically primary biogenic suspended soil minerals or windblown dust, and high ozone concentrations. Ozone levels are highest during periods of low wind when coarse particulate is likely to be at a minimum. On the other hand, secondary particles and O3 should be correlated on short time scales because both species tend to have the same precursors, NOx and VOC's, and formation of particles is favored during stagnant conditions. Fine particles (PM2.5) should also correlate with CO since both species have a common emission source. Wind

A Tale of Two Cities - HSI-DOAS Measurements of Air Quality

NASA Astrophysics Data System (ADS)

Graves, Rosemarie; Leigh, Roland; Anand, Jasdeep; McNally, Michael; Lawrence, James; Monks, Paul

2013-04-01

Differential Optical Absorption Spectroscopy is now commonly used as an air quality measuring system; primarily through the measurements of nitrogen dioxide (NO2) both as a ground-based and satellite technique. CityScan is a Hemispherical Scanning Imaging Differential Optical Absorption Spectrometer (HSI-DOAS) which has been optimised to measure concentrations of nitrogen dioxide. CityScan has a 95˚ field of view (FOV) between the zenith and 5˚ below the horizon. Across this FOV there are 128 resolved elements which are measured concurrently, the spectrometer is rotated azimuthally 1˚ per second providing full hemispherical coverage every 6 minutes. CityScan measures concentrations of nitrogen dioxide over specific lines of sight and due to the extensive field of view of the instrument this produces measurements which are representative over city-wide scales. Nitrogen dioxide is an important air pollutant which is produced in all combustion processes and can reduce lung function; especially in sensitised individuals. These instruments aim to bridge the gap in spatial scales between point source measurements of air quality and satellite measurements of air quality offering additional information on emissions, transport and the chemistry of nitrogen dioxide. More information regarding the CityScan technique can be found at http://www.leos.le.ac.uk/aq/index.html. CityScan has been deployed in both London and Bologna, Italy during 2012. The London deployment took place as part of the large NERC funded ClearfLo project in January and July/August. CityScan was deployed in Bologna in June as part of the large EU project PEGASOS. Analysis of both of these campaigns of data will be used to give unprecedented levels of spatial information to air quality measurements whilst also showing the difference in air quality between a relatively isolated mega city and a smaller city situated in a very polluted region; in this case the Po Valley. Results from multiple City

Galex and Pan-STARRS1 Discovery of SN IIP 2010aq: The First Few Days After Shock Breakout in a Red Supergiant Star

DTIC Science & Technology

2010-09-01

compare the late- time (φ > 3 d) UV/optical light curve of SN 2010aq with two nearby Type IIP SNe well studied in the UV and optical with the Swift satellite ...following SN shock breakout in a red supergiant star. SN 2010aq was discovered in joint monitoring between the Galaxy Evolution Explorer (GALEX) Time ...simultaneous UV and optical photometry allows us to fit for a progenitor star radius of 700± 200R, the size of a red supergiant star. An excess in UV emission

Air quality and future energy system planning

NASA Astrophysics Data System (ADS)

Sobral Mourao, Zenaida; Konadu, Dennis; Lupton, Rick

2016-04-01

energy system planning. Some example applications of this work are: (1) to discover conflicts and synergies between air quality regulations and future developments in the energy system and land use change; (2) to show the drivers of air quality in a given spatial context; (3) to explore effective ways to visualize impacts of different energy, land use and emissions control policies on air quality. An initial test case for the Bay Area in California will be presented, extending the scope of the existing California ForeseerTM tool to identify impacts of different policies within the water-energy-land nexus on local air quality.

Top-down constraints of regional emissions for KORUS-AQ 2016 field campaign

NASA Astrophysics Data System (ADS)

Bae, M.; Yoo, C.; Kim, H. C.; Kim, B. U.; Kim, S.

2017-12-01

Accurate estimations of emission rates form local and international sources are essential in regional air quality simulations, especially in assessing the relative contributions from international emission sources. While bottom-up constructions of emission inventories provide detailed information on specific emission types, they are limited to cover regions with rapid change of anthropogenic emissions (e.g. China) or regions without enough socioeconomic information (e.g. North Korea). We utilized space-borne monitoring of major pollutant precursors to construct a realistic emission inputs for chemistry transport models during the KORUS-AQ 2016 field campaign. Base simulation was conducted using WRF, SMOKE, and CMAQ modeling frame using CREATE 2015 (Asian countries) and CAPSS 2013 (South Korea) emissions inventories. NOx, SO2 and VOC model emissions are adjusted using the column density comparisons ratios (between modeled and observed NO2, SO2 and HCHO column densities) and emission-to-density conversion ratio (from model). Brute force perturbation method was used to separate contributions from North Korea, China and South Korea for flight pathways during the field campaign. Backward-Tracking Model Analyzer (BMA), based on NOAA HYSPLIT trajectory and dispersion model, are also utilized to track histories of chemical processes and emission source apportionment. CMAQ simulations were conducted over East Asia (27-km) and over South and North Korea (9-km) during KORUS-AQ campaign (1st May to 10th June 2016).

Determination of Water Soluble Organic Carbon Collected ~1 km above the Earth's Surface during a Mid-Atlantic Air Quality Episode and Comparison to Aerosol Optical Properties

NASA Astrophysics Data System (ADS)

Brent, L. C.; He, H.; Arkinson, H. L.; Stehr, J. W.; Ring, A.; Marufu, L.; Reiner, J.; Sander, L. C.; Dickerson, R. R.

2014-12-01

Routine, light aircraft air-monitoring conducted in MD provides insight into atmospheric photochemical processing as a function of altitude in the boundary layer and lower free troposphere. We present correlations between the optical properties and chemical composition of aerosols at ~1 km altitude over Maryland. Data were collected during the peak smog day and a dissipation day during an air quality episode studied in DISCOVER-AQ, July 2011. Post flight filter sample analysis shows a positive trend between measurable carboxylate concentrations and particle size with a recirculating, aged, urban air mass influenced with southeasterly marine winds (peak day). A westerly influx of air from the Ohio River Valley on the dissipation day was depleted in carboxylates compared with samples collected over the same location two days prior. These samples contained quantifiable concentrations of cis-pinonic acid, a reaction product of pinene after ozonation and photochemical oxidation. New techniques were developed to improve airborne data collection and analysis of water soluble organic acids (WSOA), a frequently dominant fraction of particulate matter (PM). An ion chromatographic mass spectrometric method was developed using NIST Standard Referencing Material 1649b, Urban Dust, as a surrogate material to achieve separation and resolution of at least 34 organic acids. Analysis of aircraft filter samples resulted in detection of 16 organic acids of which 12 were quantified. Eight inorganic species were also quantified. Aged, re-circulated metropolitan air showed a greater number of dicarboxylic acids than new transport air from the west and may provide a useful test of SOA formation theory.

Calculation of boron-isotope fractionation between B(OH) 3(aq) and B(OH)4-(aq)

NASA Astrophysics Data System (ADS)

Rustad, James R.; Bylaska, Eric J.; Jackson, Virgil E.; Dixon, David A.

2010-05-01

Density functional and correlated molecular orbital calculations (MP2) are carried out on B(OH) 3· nH 2O clusters ( n = 0, 6, 32), and B(OH)4-· nH 2O ( n = 0, 8, 11, 32) to estimate the equilibrium distribution of 10B and 11B isotopes between boric acid and borate in aqueous solution. For the large 32-water clusters, multiple conformations are generated from ab initio molecular dynamics simulations to account for the effect of solvent fluctuations on the isotopic fractionation. We provide an extrapolated value of the equilibrium constant α34 for the isotope exchange reaction 10B(OH) 3(aq) + 11B(OH)4- (aq) = 11B(OH) 3(aq) + 11B(OH)4- (aq) of 1.026-1.028 near the MP2 complete basis set limit with 32 explicit waters of solvation. With some exchange-correlation functionals we find potentially important contributions from a tetrahedral neutral B(OH) 3·H 2O Lewis acid-base complex. The extrapolations presented here suggest that DFT calculations give a value for 10 3ln α34 about 15% higher than the MP2 calculations.

Enforcement of continuous compliance with air quality regulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrington, C.W.

1985-01-01

The compliance of stationary air-pollution sources with air quality regulations is examined. Contrary to the predictions of economic models of enforcement, sources are generally in continuous compliance with the regulations. An alternative voluntary compliance model of enforcement is proposed, in which regulated sources are penalized not for violations, but for failing to return to compliance when a violation is discovered. It is argued that continuous compliance is a bargain struck between the source and the regulatory agency, in which the agency agrees to avoid use of penalties in return for the source's good faith attempts to maintain compliance.

Observation-based modelling and analysis of O3 Production in the Seoul Metropolitan Area during KORUS-AQ

NASA Astrophysics Data System (ADS)

Schroeder, J.; Crawford, J. H.; Fried, A.; Weinheimer, A. J.; Blake, D. R.; Blake, N. J.; Wisthaler, A.; Lee, G.; Ahn, J. Y.

2017-12-01

The Seoul Metropolitan Area (SMA) has a population of 24 million and frequently experiences unhealthy levels of ozone (O3). In this work, data from the Korea-United States Air Quality Study (KORUS-AQ, May 2 - June 11, 2016) were used to constrain a 0-D photochemical box model, allowing for calculation of key photochemical parameters related to O3 chemistry in the SMA. During KORUS-AQ, the NASA DC-8 flew 20 research flights over the Korean Peninsula. Routine overflights of the SMA in the morning, midday, and afternoon allowed for evaluation of diurnal photochemical tendencies in both the urban core of Seoul and surrounding areas. During KORUS-AQ, the SMA experienced 39 days where the max 8-hour O3 exceeded the Korean AQS value of 60 ppbv. Box model calculations constrained with high-frequency data from the DC-8 show that rates of net O3 production (P(O3)) in urban Seoul were similar to outlying metropolitan areas across all times of day, with the highest median values occurring around midday in both cases ( 15 ppbv/hr). Although mixing ratios of key ozone precursors such as NOx and reactive VOCs were substantially higher in urban Seoul than outlying areas, net P(O3) was sustained across the region due to non-linearities in O3 chemistry. Box model calculations show that urban Seoul was strongly radical-limited, while outlying areas were either slightly NOx-limited or near the `transition' area. This suggests that P(O3) can be mitigated in urban Seoul by reducing VOC emissions, but regional air quality would benefit from reductions in both NOx and VOCs. Box model simulations of the response of P(O3) to omitting select VOCs suggest that reactive aromatics - particularly toluene, which had a median mixing ratio of 2 ppbv across SMA - contributed most to radical abundances ( 60%) and P(O3), and reductions in aromatic emissions would be most effective towards reducing P(O3). Biogenics and light alkenes account for 25% and 10% of radical abundances in the SMA, respectively

76 FR 27290 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; Kentucky; Ohio...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-11

...EPA is proposing to make two determinations regarding the tri- state Huntington-Ashland, West Virginia-Kentucky-Ohio fine particulate matter (PM2.5) nonattainment Area (hereafter referred to as ``the Huntington-Ashland Area'' or ``Area''). First, EPA is proposing to determine that the Area has attained the 1997 annual average PM2.5 National Ambient Air Quality Standard (NAAQS). This proposed determination of attainment is based upon complete, quality- assured and certified ambient air monitoring data for the 2007-2009 period showing that the Area has attained the 1997 annual PM2.5 NAAQS, and data available to date for 2010 in EPA's Air Quality System (AQS) database that show the area continues to attain. If EPA finalizes this proposed determination of attainment, the requirements for the Area to submit attainment demonstrations and associated reasonably available control measures (RACM), a reasonable further progress (RFP) plan, contingency measures, and other planning State Implementation Plan (SIP) revisions related to attainment of the standard shall be suspended for so long as the Area continues to attain the annual PM2.5 NAAQS. Second, EPA is also proposing to determine, based on quality-assured and certified monitoring data for the 2007-2009 monitoring period, that the Area has attained the 1997 annual PM2.5 NAAQS by its applicable attainment date of April 5, 2010.

Reactivity and Air Composition at Taehwa Research Forest During KORUS-AQ 2016

NASA Astrophysics Data System (ADS)

Sanchez, D.; Seco, R.; Gu, D.; Jeong, D.; Blake, D. R.; Herndon, S. C.; Lee, Y.; Mak, J. E.; McGee, T. J.; Guenther, A. B.; Kim, S.

2017-12-01

The existence of unmeasured volatile organic compounds (VOCs) has been strongly suggested by past studies. Combining OH reactivity (inverse OH lifetime) observations, or total reactivity of ambient air, with VOC and other trace gas observations allows us to examine reactive gas budgets. Previous studies at various field sites have shown that significant amounts of OH reactivity cannot be accounted for, especially in areas influenced by biogenic VOCs and their oxidation products. Thus, we will present the improvements in completing the OH reactivity budget at the Taehwa research forest using the OH reactivity, VOC, and other trace gas observations conducted from May to June during the KORUS-AQ 2016 campaign in South Korea. OH reactivity was measured using the comparative reactivity method with chemical ionization mass spectrometry (CRM-CIMS). The VOCs were measured using a proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). A preliminary assessment of the OH reactivity budget at the Taehwa research using only conventionally measured trace gases and VOCs demonstrated that 54% of OH reactivity remained unaccounted. However, the improved mass resolution and sensitivity towards higher mass compounds (m/z > 100) of the PTR-ToF-MS allowed us to observe typically unmeasured VOCs. Identification of these VOCs may help account for the remaining missing OH reactivity observed at the Taehwa research forest.

Quantum chemical study, spectroscopic investigations, NBO and HOMO-LUMO analyses of 3-aminoquinoline (3AQ) and [Ag(3AQ)2(TCA)] complex (TCA = Trichloroacetate)

NASA Astrophysics Data System (ADS)

Soliman, Saied M.; Kassem, Taher S.; Badr, Ahmed M. A.; Abu Youssef, Morsy A.; Assem, Rania

2014-09-01

The new [Ag(3AQ)2(TCA)]; (3AQ = 3-aminoquinoline and TCA = Trichloroacetate) complex is synthesized and characterized using elemental analysis, FTIR, NMR and mass spectroscopy. The molecular geometry, vibrational frequencies, gauge-including atomic orbital (GIAO) 1H chemical shift values of the free and coordinated 3AQ in the ground state have been calculated by using DFT/B3LYP method. The TD-DFT results of the [Ag(3AQ)2(TCA)] complex showed a π-π* transition band at 240.3-242.6 nm (f = 0.1334-0.1348) which has longer wavelength and lower absorption intensity than that for the free 3AQ (233.2 nm, f = 0.3958). Dipole moment, polarizability and HOMO-LUMO gap values predicted better nonlinear optical properties (NLO) for the [Ag(3AQ)2(TCA)] than the 3AQ ligand. NBO analysis has been used to predict the most accurate Lewis structure of the studied molecules. The energies of the different intramolecular charge transfer (ICT) interactions within the studied molecules were estimated using second order perturbation theory.

The FireWork air quality forecast system with near-real-time biomass burning emissions: Recent developments and evaluation of performance for the 2015 North American wildfire season

PubMed Central

Pavlovic, Radenko; Chen, Jack; Anderson, Kerry; Moran, Michael D.; Beaulieu, Paul-André; Davignon, Didier; Cousineau, Sophie

2016-01-01

ABSTRACT Environment and Climate Change Canada’s FireWork air quality (AQ) forecast system for North America with near-real-time biomass burning emissions has been running experimentally during the Canadian wildfire season since 2013. The system runs twice per day with model initializations at 00 UTC and 12 UTC, and produces numerical AQ forecast guidance with 48-hr lead time. In this work we describe the FireWork system, which incorporates near-real-time biomass burning emissions based on the Canadian Wildland Fire Information System (CWFIS) as an input to the operational Regional Air Quality Deterministic Prediction System (RAQDPS). To demonstrate the capability of the system we analyzed two forecast periods in 2015 (June 2–July 15, and August 15–31) when fire activity was high, and observed fire-smoke-impacted areas in western Canada and the western United States. Modeled PM2.5 surface concentrations were compared with surface measurements and benchmarked with results from the operational RAQDPS, which did not consider near-real-time biomass burning emissions. Model performance statistics showed that FireWork outperformed RAQDPS with improvements in forecast hourly PM2.5 across the region; the results were especially significant for stations near the path of fire plume trajectories. Although the hourly PM2.5 concentrations predicted by FireWork still displayed bias for areas with active fires for these two periods (mean bias [MB] of –7.3 µg m−3 and 3.1 µg m−3), it showed better forecast skill than the RAQDPS (MB of –11.7 µg m−3 and –5.8 µg m−3) and demonstrated a greater ability to capture temporal variability of episodic PM2.5 events (correlation coefficient values of 0.50 and 0.69 for FireWork compared to 0.03 and 0.11 for RAQDPS). A categorical forecast comparison based on an hourly PM2.5 threshold of 30 µg m−3 also showed improved scores for probability of detection (POD), critical success index (CSI), and false alarm rate (FAR

The FireWork air quality forecast system with near-real-time biomass burning emissions: Recent developments and evaluation of performance for the 2015 North American wildfire season.

PubMed

Pavlovic, Radenko; Chen, Jack; Anderson, Kerry; Moran, Michael D; Beaulieu, Paul-André; Davignon, Didier; Cousineau, Sophie

2016-09-01

Environment and Climate Change Canada's FireWork air quality (AQ) forecast system for North America with near-real-time biomass burning emissions has been running experimentally during the Canadian wildfire season since 2013. The system runs twice per day with model initializations at 00 UTC and 12 UTC, and produces numerical AQ forecast guidance with 48-hr lead time. In this work we describe the FireWork system, which incorporates near-real-time biomass burning emissions based on the Canadian Wildland Fire Information System (CWFIS) as an input to the operational Regional Air Quality Deterministic Prediction System (RAQDPS). To demonstrate the capability of the system we analyzed two forecast periods in 2015 (June 2-July 15, and August 15-31) when fire activity was high, and observed fire-smoke-impacted areas in western Canada and the western United States. Modeled PM2.5 surface concentrations were compared with surface measurements and benchmarked with results from the operational RAQDPS, which did not consider near-real-time biomass burning emissions. Model performance statistics showed that FireWork outperformed RAQDPS with improvements in forecast hourly PM2.5 across the region; the results were especially significant for stations near the path of fire plume trajectories. Although the hourly PM2.5 concentrations predicted by FireWork still displayed bias for areas with active fires for these two periods (mean bias [MB] of -7.3 µg m(-3) and 3.1 µg m(-3)), it showed better forecast skill than the RAQDPS (MB of -11.7 µg m(-3) and -5.8 µg m(-3)) and demonstrated a greater ability to capture temporal variability of episodic PM2.5 events (correlation coefficient values of 0.50 and 0.69 for FireWork compared to 0.03 and 0.11 for RAQDPS). A categorical forecast comparison based on an hourly PM2.5 threshold of 30 µg m(-3) also showed improved scores for probability of detection (POD), critical success index (CSI), and false alarm rate (FAR). Smoke from wildfires

Measured and Modeled Hydroxyl (OH) and Hydroperoxyl (HO2) During KORUS-AQ

NASA Astrophysics Data System (ADS)

Brosius, A. L.; Brune, W. H.; Thames, A. B.; Miller, D. O.

2017-12-01

In the troposphere, hydroxyl (OH) reacts with most atmospheric pollutants, initiating their removal from the atmosphere and in some cases creating other atmospheric pollutants, such as ozone and small particles. Hydroperoxyl (HO2) also plays a role in oxidation chemistry by producing tropospheric ozone (O3). Air pollution in Korea is a combination of locally generated pollution, aged pollution from China, and the interaction of local pollution with forest emissions. Thus, OH and HO2 interact with a complex soup of chemical species over Korea, providing a stringent test for the understanding of atmospheric oxidation chemistry. During KORUS-AQ, we measured OH and HO2 using the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) as part of a large instrument suite installed on the NASA DC-8 aircraft. We use the Master Chemical Mechanism (MCM), constrained by the simultaneous measurement of many of chemical species to calculate OH and HO2. While the measured and modeled OH and HO2 generally agree within combined uncertainties, there are substantial discrepancies. We will discuss possible reasons for the discrepancies and the implications for air quality regulatory policy.

Satellite-Derived NO2 as an Indicator of Urban Air Quality and Emissions

NASA Astrophysics Data System (ADS)

Holloway, T.; Penn, E.; Harkey, M.

2016-12-01

Nitrogen dioxide (NO2) is the satellite-derived constituent with the most direct connection to fossil fuel emissions. At present the Ozone Monitoring Instrument aboard the NASA Aura satellite offers the highest resolution NO2retrievals, and new missions under development (TropOMI, TEMPO, GEMS, Sentinel-4) offer the potential for improved data in coming years. We present results applying satellite-derived NO2data to characterize air quality and emissions in U.S. cities. We highlight research findings geared toward increasing the relevance of satellite data to evaluate urban-scale air quality issues. This work reflects activities under the NASA Air Quality Applied Sciences Team (AQAST), and emerging work under the NASA Health and Air Quality Applied Sciences Team (H-AQAST). Among our results is a characterization of the diurnal cycle of nitrogen oxides using ground-based observations and satellite data. In situ monitoring from the U.S. EPA Air Quality System (AQS) shows that most locations have two daily peaks in NO2 (morning and evening) and a single daily peak in NO (morning). Spaced-based observations from the ESA Global Ozone Monitoring Experiment-2 (GOME-2), with a mid-morning overpass, and the NASA OMI, with an early afternoon overpass, support a complementary analysis for characterizing diurnal variability in NO2. Both ground-based monitors and satellite data show a reduction in the amplitude of the diurnal NO2 cycle. In the Western U.S., satellite data showed evidence of higher NO2 in urban centers in the afternoon (OMI) and higher NO2 in suburban areas in the morning (GOME-2), consistent with diurnal traffic patterns associated with commuting. Some power plants in the Western U.S. showed an increase in NO2in the afternoon, consistent with peak power demand associated with building air conditioning use. We extend this city-focused analysis satellite-derived HCHO:NO2 ratios as an indicator of ozone production regime, comparing modeled and measured ratios

AQS-20 through-the-sensor environmental data sharing

NASA Astrophysics Data System (ADS)

Steed, Chad A.; Sample, John; Harris, Mike; Avera, Will; Bibee, L. Dale

2005-05-01

The Naval Research Laboratory (NRL) has developed an advanced architecture for connecting many maturing Through-The-Sensor (TTS) efforts for an end-to-end demonstration using the AQS-20 mine hunting sensor. The goal of TTS technologies is to exploit tactical sensors to characterize the battlespace environment for Navy Fleet Tactical Decision Aids (TDAs) with minimal impact on tactical systems. The AQS-20 Rapid Transition Process (RTP) will utilize the AQS-20 to demonstrate sensor data collection, processing, fusion, storage, distribution and use in a tactical decision aid. In recent years, NRL has shown that the AQS-20 can be used to obtain swath bathymetry and bottom sediment information in a single flight. In the AQS-20 RTP, these data will be processed and fused with historical databases to provide an improved environmental picture. The RTP will also utilize the Geophysical Data Base Variable resolution (GDBV) dynamic format for storing local datasets. The GDBV dynamic has been developed in prior years to provide an extensible, efficient data storage format for TTS systems. To provide the interconnectivity that is critical to Network Centric Warfare (NCW), the GDBV will be connected to the SPAWAR funded Tactical Environmental Data Services (TEDServices). To complete the flow of information from sensor to user, the RTP will transmit information to the MEDAL TDA through existing connections in The Naval Oceanographic Office"s (NAVOCEANO) Bottom Mapping Workstation (BMW). In addition, TEDServices will handle transmission of the AQS-20 data to NAVOCEANO who serves as the domain authority for oceanographic datasets in the U.S. Navy.

A novel, fuzzy-based air quality index (FAQI) for air quality assessment

NASA Astrophysics Data System (ADS)

Sowlat, Mohammad Hossein; Gharibi, Hamed; Yunesian, Masud; Tayefeh Mahmoudi, Maryam; Lotfi, Saeedeh

2011-04-01

The ever increasing level of air pollution in most areas of the world has led to development of a variety of air quality indices for estimation of health effects of air pollution, though the indices have their own limitations such as high levels of subjectivity. Present study, therefore, aimed at developing a novel, fuzzy-based air quality index (FAQI ) to handle such limitations. The index developed by present study is based on fuzzy logic that is considered as one of the most common computational methods of artificial intelligence. In addition to criteria air pollutants (i.e. CO, SO 2, PM 10, O 3, NO 2), benzene, toluene, ethylbenzene, xylene, and 1,3-butadiene were also taken into account in the index proposed, because of their considerable health effects. Different weighting factors were then assigned to each pollutant according to its priority. Trapezoidal membership functions were employed for classifications and the final index consisted of 72 inference rules. To assess the performance of the index, a case study was carried out employing air quality data at five different sampling stations in Tehran, Iran, from January 2008 to December 2009, results of which were then compared to the results obtained from USEPA air quality index (AQI). According to the results from present study, fuzzy-based air quality index is a comprehensive tool for classification of air quality and tends to produce accurate results. Therefore, it can be considered useful, reliable, and suitable for consideration by local authorities in air quality assessment and management schemes. Fuzzy-based air quality index (FAQI).

A computerized system to measure and predict air quality for emission control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crooks, G.; Ciccone, A.; Frattolillo, P.

1997-12-31

A Supplementary Emission Control (SEC) system has been developed on behalf of the Association Industrielle de l`Est de Montreal (AIEM). The objective of the SEC is to avoid exceedences of the Montreal Urban Community (MUC) 24 hour ambient Air Quality Standard (AQS) for sulphur dioxide in the industrial East Montreal area. The SEC system is comprised of: 3 continuous SO{sub 2} monitoring stations with data loggers and remote communications; a meteorological tower with data logger and modem for acquiring local meteorology; communications with Environment Canada to download meteorological forecast data; a polling PC for data retrieval; and Windows NT basedmore » software running on the AIEM computer server. The SEC software utilizes relational databases to store and maintain measured SO{sub 2} concentration data, emission data, as well as observed and forecast meteorological data. The SEC system automatically executes a numerical dispersion model to forecast SO{sub 2} concentrations up to six hours in the future. Based on measured SO{sub 2} concentrations at the monitoring stations and the six hour forecast concentrations, the system determines if local sources should reduce their emission levels to avoid potential exceedences of the AQS. The SEC system also includes a Graphical User Interface (GUI) for user access to the system. The SEC system and software are described, and the accuracy of the system at forecasting SO{sub 2} concentrations is examined.« less

Retrospective observational study of emergency department syndromic surveillance data during air pollution episodes across London and Paris in 2014

PubMed Central

Morbey, Roger; Fouillet, Anne; Caserio-Schönemann, Céline; Dobney, Alec; Hughes, Thomas C; Smith, Gillian E

2018-01-01

Introduction Poor air quality (AQ) is a global public health issue and AQ events can span across countries. Using emergency department (ED) syndromic surveillance from England and France, we describe changes in human health indicators during periods of particularly poor AQ in London and Paris during 2014. Methods Using daily AQ data for 2014, we identified three periods of poor AQ affecting both London and Paris. Anonymised near real-time ED attendance syndromic surveillance data from EDs across England and France were used to monitor the health impact of poor AQ. Using the routine English syndromic surveillance detection methods, increases in selected ED syndromic indicators (asthma, difficulty breathing and myocardial ischaemia), in total and by age, were identified and compared with periods of poor AQ in each city. Retrospective Wilcoxon-Mann-Whitney tests were used to identify significant increases in ED attendance data on days with (and up to 3 days following) poor AQ. Results Almost 1.5 million ED attendances were recorded during the study period (27 February 2014 to 1 October 2014). Significant increases in ED attendances for asthma were identified around periods of poor AQ in both cities, especially in children (aged 0–14 years). Some variation was seen in Paris with a rapid increase during the first AQ period in asthma attendances among children (aged 0–14 years), whereas during the second period the increase was greater in adults. Discussion This work demonstrates the public health value of syndromic surveillance during air pollution incidents. There is potential for further cross-border harmonisation to provide Europe-wide early alerting to health impacts and improve future public health messaging to healthcare services to provide warning of increases in demand. PMID:29674360

Retrospective observational study of emergency department syndromic surveillance data during air pollution episodes across London and Paris in 2014.

PubMed

Hughes, Helen E; Morbey, Roger; Fouillet, Anne; Caserio-Schönemann, Céline; Dobney, Alec; Hughes, Thomas C; Smith, Gillian E; Elliot, Alex J

2018-04-19

Poor air quality (AQ) is a global public health issue and AQ events can span across countries. Using emergency department (ED) syndromic surveillance from England and France, we describe changes in human health indicators during periods of particularly poor AQ in London and Paris during 2014. Using daily AQ data for 2014, we identified three periods of poor AQ affecting both London and Paris. Anonymised near real-time ED attendance syndromic surveillance data from EDs across England and France were used to monitor the health impact of poor AQ.Using the routine English syndromic surveillance detection methods, increases in selected ED syndromic indicators (asthma, difficulty breathing and myocardial ischaemia), in total and by age, were identified and compared with periods of poor AQ in each city. Retrospective Wilcoxon-Mann-Whitney tests were used to identify significant increases in ED attendance data on days with (and up to 3 days following) poor AQ. Almost 1.5 million ED attendances were recorded during the study period (27 February 2014 to 1 October 2014). Significant increases in ED attendances for asthma were identified around periods of poor AQ in both cities, especially in children (aged 0-14 years). Some variation was seen in Paris with a rapid increase during the first AQ period in asthma attendances among children (aged 0-14 years), whereas during the second period the increase was greater in adults. This work demonstrates the public health value of syndromic surveillance during air pollution incidents. There is potential for further cross-border harmonisation to provide Europe-wide early alerting to health impacts and improve future public health messaging to healthcare services to provide warning of increases in demand. © Crown copyright 2018. Reproduced with the permission of the Controller of Her Majesty’s Stationery Office/Queen’s Printer for Scotland and Public Health England.

Ambient Air Quality Data Inventory

EPA Pesticide Factsheets

The Office of Air and Radiation's (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as state, local, and tribal air pollution control agencies. Its component data sets have been collected over the years from approximately 10,000 monitoring sites, of which approximately 5,000 are currently active. OAR's Office of Air Quality Planning and Standards (OAQPS) and other internal and external users, rely on this data to assess air quality, assist in Attainment/Non-Attainment designations, evaluate State Implementation Plans for Non-Attainment Areas, perform modeling for permit review analysis, and other air quality management functions. Air quality information is also used to prepare reports for Congress as mandated by the Clean Air Act. This data covers air quality data collected after 1980, when the Clean Air Act requirements for monitoring were significantly modified. Air quality data from the Agency's early years (1970s) remains available (see OAR PRIMARY DATA ASSET: Ambient Air Quality Data -- Historical), but because of technical and definitional differences the two data assets are not directly comparable. The Clean Air Act of 1970 provided initial authority for monitoring air quality for Conventional Air Pollutants (CAPs) for which EPA has promulgated National Ambient Air Quality Standards (NAAQS). Requirements for monitoring visibility-related parameters were added in 1977. Requiremen

Performance assessment of future thermal infrared geostationary instruments to monitor air quality

NASA Astrophysics Data System (ADS)

Sellitto, P.; Dauphin, P.; Dufour, G.; Eremenko, M.; Cuesta, J.; Coman, A.; Forêt, G.; Beekmann, M.; Gaubert, B.; Flaud, J.-M.

2012-04-01

Air quality (AQ) has a recognized onerous impact on human health and the environment, and then on society. It is more and more clear that constantly and efficiently monitoring AQ from space is a valuable step forward towards a more thorough comprehension of pollution processes that can have a relevant impact on the biosphere. In recent years, important progresses in this field have been made, e.g., reliable observations of several pollutants have been obtained, proving the feasibility of monitoring atmospheric composition from space. In this sense, low Earth orbit (LEO) thermal infrared (TIR) space-borne instruments are widely regarded as a useful tool to observe targeted AQ parameters like tropospheric ozone concentrations [1]. However, limitations remain with the current observation systems in particular to observe ozone in the lowermost troposphere (LmT) with a spatial and temporal resolution relevant for monitoring pollution processes at the regional scale. Indeed, LEO instruments are not well adapted to monitor small scale and short term phenomena, owing to their unsatisfactory revisit time. From this point of view, a more satisfactory concept might be based on geostationary (GEO) platforms. Current and planned GEO missions are mainly tailored on meteorological parameters retrieval and do not have sufficient spectral resolutions and signal to noise ratios (SNR) to infer information on trace gases in the LmT. New satellite missions are currently proposed that can partly overcome these limitations. Here we present a group of simulation exercises and sensitivity analyses to set-up future TIR GEO missions adapted to monitor and forecast AQ over Europe, and to evaluate their technical requirements. At this aim, we have developed a general simulator to produce pseudo-observations for different platform/instrument configurations. The core of this simulator is the KOPRA radiative transfer model, including the KOPRAfit inversion module [2]. Note that to assess the

78 FR 53270 - Revision of Air Quality Implementation Plan; California; Sacramento Metropolitan Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-29

... Quality Implementation Plan; California; Sacramento Metropolitan Air Quality Management District... to the Sacramento Metropolitan Air Quality Management District (SMAQMD or District) portion of the..., Sacramento Metropolitan Air Quality Management District, Rule 214 (Federal New Source Review), Rule 203...

Local Air Quality Conditions and Forecasts

MedlinePlus

... Monitor Location Archived Maps by Region Canada Air Quality Air Quality on Google Earth Links A-Z About AirNow AirNow International Air Quality Action Days / Alerts AirCompare Air Quality Index (AQI) ...

78 FR 30770 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards Revision AGENCY... Illinois state implementation plan (SIP) to reflect current National Ambient Air Quality Standards (NAAQS... Implementation Plan at 35 Illinois Administrative Code part 243, which updates National Ambient Air Quality...

A new air quality monitoring and early warning system: Air quality assessment and air pollutant concentration prediction.

PubMed

Yang, Zhongshan; Wang, Jian

2017-10-01

Air pollution in many countries is worsening with industrialization and urbanization, resulting in climate change and affecting people's health, thus, making the work of policymakers more difficult. It is therefore both urgent and necessary to establish amore scientific air quality monitoring and early warning system to evaluate the degree of air pollution objectively, and predict pollutant concentrations accurately. However, the integration of air quality assessment and air pollutant concentration prediction to establish an air quality system is not common. In this paper, we propose a new air quality monitoring and early warning system, including an assessment module and forecasting module. In the air quality assessment module, fuzzy comprehensive evaluation is used to determine the main pollutants and evaluate the degree of air pollution more scientifically. In the air pollutant concentration prediction module, a novel hybridization model combining complementary ensemble empirical mode decomposition, a modified cuckoo search and differential evolution algorithm, and an Elman neural network, is proposed to improve the forecasting accuracy of six main air pollutant concentrations. To verify the effectiveness of this system, pollutant data for two cities in China are used. The result of the fuzzy comprehensive evaluation shows that the major air pollutants in Xi'an and Jinan are PM 10 and PM 2.5 respectively, and that the air quality of Xi'an is better than that of Jinan. The forecasting results indicate that the proposed hybrid model is remarkably superior to all benchmark models on account of its higher prediction accuracy and stability. Copyright © 2017 Elsevier Inc. All rights reserved.

The Autism Spectrum Quotient: Children's Version (AQ-Child)

ERIC Educational Resources Information Center

Auyeung, Bonnie; Baron-Cohen, Simon; Wheelwright, Sally; Allison, Carrie

2008-01-01

The Autism Spectrum Quotient-Children's Version (AQ-Child) is a parent-report questionnaire that aims to quantify autistic traits in children 4-11 years old. The range of scores on the AQ-Child is 0-150. It was administered to children with an autism spectrum condition (ASC) (n = 540) and a general population sample (n = 1,225). Results showed a…

78 FR 10589 - Revision of Air Quality Implementation Plan; California; Sacramento Metropolitan Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-14

... Quality Implementation Plan; California; Sacramento Metropolitan Air Quality Management District... Sacramento Metropolitan Air Quality Management District (SMAQMD or District) portion of the California State... sources within the areas covered by the plan as necessary to assure that the National Ambient Air Quality...

Assessing the Association Between Asthma and Air Quality in the Presence of Wildfires

NASA Astrophysics Data System (ADS)

Young, L. J.; Al-Hamdan, M. Z.; Lopiano, K. K.; Crosson, W. L.; Gotway, C. A.; DuClos, C.; Jordan, M.; Estes, M. G.; Luvall, J. C.; Estes, S. M.; Xu, X.; Holt, N. M.; Leary, E.

2012-12-01

Asthma hospital/emergency room (patient) data are used as the foundation for creating a health outcome indicator of human response to environmental air quality. Daily U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) fine particulates (PM2.5) ground data and the U.S. National Aeronautical Space Administration (NASA) MODIS aerosol optical depth (AOD) data were acquired and processed for years of 2007 and 2008. Figure 1 shows the PM2.5 annual mean composite of all the 2007 B-spline daily surfaces. Initial models for predicting the number of weekly asthma cases within a Florida county has focused on environmental variables. Weekly maximums of PM2.5, relative humidity, and the proportions of the county with smoke and fire were the environmental variables included in the model. Cosine and sine functions of time were used to account for seasonality in asthma cases. Counties were considered to be random effects, thereby adjusting for differences in socio-demographics and other factors. The 2007 predictions for Miami-Dade county when using B-splines PM2.5 are displayed in Figures 2.; PM2.5 annual mean composite of all the 2007 daily surfaces developed using Al-Hamdan et al (2009) B-spline fitting algorithm ; Predicted and observed weekly asthma cases presenting to hospitals or emergency rooms in Miami-Dade county in Florida during 2007

Air Pollution Monitoring | Air Quality Planning & Standards ...

EPA Pesticide Factsheets

2016-06-08

The basic mission of the Office of Air Quality Planning and Standards is to preserve and improve the quality of our nation's air. To accomplish this, OAQPS must be able to evaluate the status of the atmosphere as compared to clean air standards and historical information.

78 FR 63934 - Approval of Air Quality Implementation Plans; California; El Dorado County Air Quality Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

...] Approval of Air Quality Implementation Plans; California; El Dorado County Air Quality Management District... California for the El Dorado County Air Quality Management District (EDAQMD) portion of the California SIP... 24, 1987 Federal Register, May 25, 1988, U.S. EPA, Air Quality Management Division, Office of Air...

Air quality management in Mexico.

PubMed

Fernández-Bremauntz, Adrián

2008-01-01

Several significant program and policy measures have been implemented in Mexico over the past 15 yr to improve air quality. This article provides an overview of air quality management strategies in Mexico, including (1) policy initiatives such as vehicle use restrictions, air quality standards, vehicle emissions, and fuel quality standards, and (2) supporting programs including establishment of a national emission inventory, an air pollution episodes program, and the implementation of exposure and health effects studies. Trends in air pollution episodes and ambient air pollutant concentrations are described.

78 FR 30829 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards Revision AGENCY... the Illinois State Implementation Plan (SIP) to reflect current national ambient air quality standards...) 692-2450. 4. Mail: Pamela Blakley, Chief, Control Strategies Section, Air Programs Branch (AR-18J), U...

Developing air quality forecasts

NASA Astrophysics Data System (ADS)

Lee, Pius; Saylor, Rick; Meagher, James

2012-05-01

Third International Workshop on Air Quality Forecasting Research; Potomac, Maryland, 29 November to 1 December 2011 Elevated concentrations of both near-surface ozone (O3) and fine particulate matter smaller than 2.5 micrometers in diameter have been implicated in increased mortality and other human health impacts. In light of these known influences on human health, many governments around the world have instituted air quality forecasting systems to provide their citizens with advance warning of impending poor air quality so that they can take actions to limit exposure. In an effort to improve the performance of air quality forecasting systems and provide a forum for the exchange of the latest research in air quality modeling, the International Workshop on Air Quality Forecasting Research (IWAQFR) was established in 2009 and is cosponsored by the U.S. National Oceanic and Atmospheric Administration (NOAA), Environment Canada (EC), and the World Meteorological Organization (WMO). The steering committee for IWAQFR's establishment was composed of Véronique Bouchet, Mike Howe, and Craig Stoud (EC); Greg Carmichael (University of Iowa); Paula Davidson and Jim Meagher (NOAA); and Liisa Jalkanen (WMO). The most recent workshop took place in Maryland.

75 FR 65572 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-26

... Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards AGENCY... Ohio Administrative Code (OAC) relating to the consolidation of Ohio's Ambient Air Quality Standards... apply to Ohio's SIP. Incorporating the air quality standards into Ohio's SIP helps assure that...

A Visual Analytics Approach for Station-Based Air Quality Data

PubMed Central

Du, Yi; Ma, Cuixia; Wu, Chao; Xu, Xiaowei; Guo, Yike; Zhou, Yuanchun; Li, Jianhui

2016-01-01

With the deployment of multi-modality and large-scale sensor networks for monitoring air quality, we are now able to collect large and multi-dimensional spatio-temporal datasets. For these sensed data, we present a comprehensive visual analysis approach for air quality analysis. This approach integrates several visual methods, such as map-based views, calendar views, and trends views, to assist the analysis. Among those visual methods, map-based visual methods are used to display the locations of interest, and the calendar and the trends views are used to discover the linear and periodical patterns. The system also provides various interaction tools to combine the map-based visualization, trends view, calendar view and multi-dimensional view. In addition, we propose a self-adaptive calendar-based controller that can flexibly adapt the changes of data size and granularity in trends view. Such a visual analytics system would facilitate big-data analysis in real applications, especially for decision making support. PMID:28029117

A Visual Analytics Approach for Station-Based Air Quality Data.

PubMed

Du, Yi; Ma, Cuixia; Wu, Chao; Xu, Xiaowei; Guo, Yike; Zhou, Yuanchun; Li, Jianhui

2016-12-24

With the deployment of multi-modality and large-scale sensor networks for monitoring air quality, we are now able to collect large and multi-dimensional spatio-temporal datasets. For these sensed data, we present a comprehensive visual analysis approach for air quality analysis. This approach integrates several visual methods, such as map-based views, calendar views, and trends views, to assist the analysis. Among those visual methods, map-based visual methods are used to display the locations of interest, and the calendar and the trends views are used to discover the linear and periodical patterns. The system also provides various interaction tools to combine the map-based visualization, trends view, calendar view and multi-dimensional view. In addition, we propose a self-adaptive calendar-based controller that can flexibly adapt the changes of data size and granularity in trends view. Such a visual analytics system would facilitate big-data analysis in real applications, especially for decision making support.

77 FR 73320 - Approval of Air Quality Implementation Plans; California; South Coast Air Quality Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... Quality Implementation Plans; California; South Coast Air Quality Management District; Prevention of... Implementation Plan (SIP) revision for the South Coast Air Quality Management District (SCAQMD or District... in a August 15, 2012 letter from the South Coast Air Quality Management District regarding specific...

Multi-perspective observations of NO2 over the Denver area ...

EPA Pesticide Factsheets

The final deployment in the DISCOVER-AQ1 series of air quality field campaigns focused on the Northern Front Range of Colorado including the Denver Metropolitan Area in July-August 2014. The overarching goal of these campaigns was to improve the interpretation of satellite observations to diagnose near-surface air quality conditions. This called for observations to be combined from multiple perspectives that included ground-based as well as airborne in situ and remote sensing measurements. These observations were collected to demonstrate how future geostationary satellites could provide information of direct benefit to agencies responsible for monitoring and regulating air quality. This article focuses specifically on measurements of nitrogen dioxide (NO2), which are critical to understanding the photochemical production of ozone (O3). Published in the August issue of EM: AIR AND WASTE MANAGEMENT ASSOCIATIONS MAGAZINE FOR ENVIRONMENTAL MANAGERS

78 FR 19990 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-03

... Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards; Correction AGENCY... approved revisions to Ohio regulations that consolidated air quality standards in a new chapter of rules... State's air quality standards into Ohio Administrative Code (OAC) 3745-25 and modifying an assortment of...

77 FR 12482 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-01

... Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY... incorporates the National Ambient Air Quality Standards (NAAQS) for Pb promulgated by EPA in 2008. DATES: This... FR 66964) and codified at 40 CFR 50.16, ``National primary and secondary ambient air quality...

Ozone - Current Air Quality Index

MedlinePlus

GO! Local Air Quality Conditions Zip Code: State : My Current Location Current AQI Forecast AQI Loop More Maps AQI: Good (0 - 50) ... resources for Hawaii residents and visitors more announcements Air Quality Basics Air Quality Index | Ozone | Particle Pollution | Smoke ...

On evaluating compliance with air pollution levels 'not to be exceeded more than once per year'

NASA Technical Reports Server (NTRS)

Neustadter, H. E.; Sidik, S. M.

1974-01-01

The point of view taken is that the Environmental Protection Agency (EPA) Air Quality Standards (AQS) represent conditions which must be made to exist in the ambient environment. The statistical techniques developed should serve as tools for measuring the closeness to achieving the desired quality of air. It is shown that the sampling frequency recommended by EPA is inadequate to meet these objectives when the standard is expressed as a level not to be exceeded more than once per year and sampling frequency is once every three days or less frequent.

Orientamento della prima fase della moschea al-Aqşā di Gerusalemme

NASA Astrophysics Data System (ADS)

Di Cesare, Michelina

2017-07-01

A new interpretation of the archaeological data regarding the first of the three pre-Crusader structural phases of al-Aqşā mosque in Jerusalem (Aqşā I) is proposed. It suggests that the building had an astronomical orientation like other 7th-century and early 8th-century mosques. Thus, Aqşā I would have been oriented towards the East rather than the South, as believed so far. This hypothesis would allow to solve the anomalies of the plan of Aqşā I. Indeed, by identifying the eastern wall rather than the southern as the qiblī wall, the aisles would not result perpendicular but parallel to it and running along the long side, as usual in Umayyad mosques. Consequently, the precocious appearance of the transept in Aqşā II would be due to the re-orientation of the previous structure.

Formaldehyde Column Density Measurements as a Suitable Pathway to Estimate Near-Surface Ozone Tendencies from Space

NASA Technical Reports Server (NTRS)

Schroeder, Jason R.; Crawford, James H.; Fried, Alan; Walega, James; Weinheimer, Andrew; Wisthaler, Armin; Mueller, Markus; Mikoviny, Tomas; Chen, Gao; Shook, Michael;

Impacts of Climate Policy on Regional Air Quality, Health, and Air Quality Regulatory Procedures

NASA Astrophysics Data System (ADS)

Thompson, T. M.; Selin, N. E.

2011-12-01

Both the changing climate, and the policy implemented to address climate change can impact regional air quality. We evaluate the impacts of potential selected climate policies on modeled regional air quality with respect to national pollution standards, human health and the sensitivity of health uncertainty ranges. To assess changes in air quality due to climate policy, we couple output from a regional computable general equilibrium economic model (the US Regional Energy Policy [USREP] model), with a regional air quality model (the Comprehensive Air Quality Model with Extensions [CAMx]). USREP uses economic variables to determine how potential future U.S. climate policy would change emissions of regional pollutants (CO, VOC, NOx, SO2, NH3, black carbon, and organic carbon) from ten emissions-heavy sectors of the economy (electricity, coal, gas, crude oil, refined oil, energy intensive industry, other industry, service, agriculture, and transportation [light duty and heavy duty]). Changes in emissions are then modeled using CAMx to determine the impact on air quality in several cities in the Northeast US. We first calculate the impact of climate policy by using regulatory procedures used to show attainment with National Ambient Air Quality Standards (NAAQS) for ozone and particulate matter. Building on previous work, we compare those results with the calculated results and uncertainties associated with human health impacts due to climate policy. This work addresses a potential disconnect between NAAQS regulatory procedures and the cost/benefit analysis required for and by the Clean Air Act.

Indoor Air Quality Manual.

ERIC Educational Resources Information Center

Baldwin Union Free School District, NY.

This manual identifies ways to improve a school's indoor air quality (IAQ) and discusses practical actions that can be carried out by school staff in managing air quality. The manual includes discussions of the many sources contributing to school indoor air pollution and the preventive planning for each including renovation and repair work,…

Assessing the influence of regional transport from Mainland China over the Korean Peninsula during the 2016 KORUS-AQ Field Campaign with CO/CO2 ratios

NASA Astrophysics Data System (ADS)

Halliday, H. S.; DiGangi, J. P.; Diskin, G. S.; Choi, Y.; Pusede, S.; Rana, M.; Nowak, J. B.

2017-12-01

The industrial growth in East Asia has resulted in widespread growth and prosperity, but has been accompanied by degraded air quality. These poor air quality events have both local and regional effects, and long range transportation of pollution can greatly increase the affected populations. South Korea has a technologically oriented economy with vibrant urban regions, but suffers from poor air quality arising from both local emissions on the Korean peninsula and from the transport of pollution from Mainland China. The KORUS-AQ field campaign was an international collaboration to characterize and understand the air quality over the Korean peninsula in the spring of 2016. We use the aircraft in situ data from the DC-8 aircraft to examine trace gas ratios over three major analysis regions: the Seoul Metropolitan region, the South Korean peninsula, and the West Sea (Yellow Sea). We look specifically at the correlations between CO and CO2 as an indicator of emissions type, with low ratios generally indicative of more efficient combustion and high emission ratios indicating low efficiency combustion. At low altitudes, higher incidences of low CO/CO2 ratios were observed in the Seoul and Peninsula regions, compared to higher ratios of CO/CO2 over the West Sea. We examine the meteorological dependence of these carbon species ratios, their relationships to VOC tracers, and their vertical behavior to evaluate the air mass contributions from Mainland China and assess the percentage contributions of these regional emissions to the measurements over the Korean Peninsula.

75 FR 65594 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-26

... Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards AGENCY... the Ohio Administrative Code (OAC) relating to the consolidation of Ohio's Ambient Air Quality Standards (AAQS) into Ohio's State Implementation Plan (SIP) under the Clean Air Act. On April 8, 2009, and...

77 FR 12524 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-01

... Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY... Indiana State Implementation Plan (SIP) for lead (Pb) under the Clean Air Act (CAA). This submittal incorporates the National Ambient Air Quality Standards (NAAQS) for Pb promulgated by EPA in 2008. DATES...

AIR CLEANING FOR ACCEPTABLE INDOOR AIR QUALITY

EPA Science Inventory

The paper discusses air cleaning for acceptable indoor air quality. ir cleaning has performed an important role in heating, ventilation, and air-conditioning systems for many years. raditionally, general ventilation air-filtration equipment has been used to protect cooling coils ...

Air Quality Index (AQI) -- A Guide to Air Quality and Your Health

MedlinePlus

... Guide for Ozone Air Quality Guide for Particle Pollution Other AirNow Publications Other AirNow Publications En Español ... the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur ...

Enabling Mobile Air Quality App Development with an AirNow API

NASA Astrophysics Data System (ADS)

Dye, T.; White, J. E.; Ludewig, S. A.; Dickerson, P.; Healy, A. N.; West, J. W.; Prince, L. A.

2013-12-01

The U.S. Environmental Protection Agency's (EPA) AirNow program works with over 130 participating state, local, and federal air quality agencies to obtain, quality control, and store real-time air quality observations and forecasts. From these data, the AirNow system generates thousands of maps and products each hour. Each day, information from AirNow is published online and in other media to assist the public in making health-based decisions related to air quality. However, an increasing number of people use mobile devices as their primary tool for obtaining information, and AirNow has responded to this trend by publishing an easy-to-use Web API that is useful for mobile app developers. This presentation will describe the various features of the AirNow application programming interface (API), including Representational State Transfer (REST)-type web services, file outputs, and RSS feeds. In addition, a web portal for the AirNow API will be shown, including documentation on use of the system, a query tool for configuring and running web services, and general information about the air quality data and forecasts available. Data published via the AirNow API includes corresponding Air Quality Index (AQI) levels for each pollutant. We will highlight examples of mobile apps that are using the AirNow API to provide location-based, real-time air quality information. Examples will include mobile apps developed for Minnesota ('Minnesota Air') and Washington, D.C. ('Clean Air Partners Air Quality'), and an app developed by EPA ('EPA AirNow').

Submicron aerosol distributions and CCN activity measured in and around the Korean Peninsula during KORUS-AQ

NASA Astrophysics Data System (ADS)

Park, M.; Kim, N.; Yum, S. S.; Thornhill, K. L., II; Anderson, B. E.; Kim, D. S.; Kim, H. J.; Jeon, H. E.; Park, Y. S.; Lee, S. B.

2017-12-01

KORUS-AQ is a field campaign aimed at investigating formation of ozone and aerosol and interactions between chemistry, transport and various sources in the Korean Peninsula which is the region affected both by long-range transport and local emission. Aerosol number concentration and size distribution, and CCN number concentration were measured on board the NASA DC-8 research aircraft and at a ground site at Olympic Park in Seoul, capital city of Korea during the KORUS-AQ campaign (May 2nd to June 10th, 2017). There were 20 flights during the KORUS-AQ campaign and total flight time was about 150 hours. CCN counter (CCNC) on the airborne platform was operated at the fixed internal supersaturation of 0.6% and CCNC at the ground site was operated at five different supersaturations (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). Aerosol hygroscopic parameter κ was also estimated from CCN number concentration and aerosol size distribution. Airborne measurements showed a large spatio-temporal variation of aerosol number concentration and CCN activity in and around the Korean peninsula, and the ground measurements also showed a large temporal variation. The campaign period can be classified into long-range transport dominant cases, local emission dominant cases due to stagnant air mass, and others. Aerosol number concentration in the Korean Peninsula measured in stagnant air mass period was higher than those in long-range transport period, but CCN number concentration showed an opposite tendency. Both aerosol and CCN number concentrations over the Yellow Sea in local emission period were slightly higher than those in long-range transport period. Since CCN activity is different depending on time and space, our focus is on understanding how CCN activity and aerosol hygroscopicity vary with the source of aerosol. Comprehensive analysis results will be shown at the conference.

Photochemical Grid Modelling Study to Assess Potential Air Quality Impacts Associated with Energy Development in Colorado and Northern New Mexico.

NASA Astrophysics Data System (ADS)

Parker, L. K.; Morris, R. E.; Zapert, J.; Cook, F.; Koo, B.; Rasmussen, D.; Jung, J.; Grant, J.; Johnson, J.; Shah, T.; Pavlovic, T.

2015-12-01

The Colorado Air Resource Management Modeling Study (CARMMS) was funded by the Bureau of Land Management (BLM) to predict the impacts from future federal and non-federal energy development in Colorado and Northern New Mexico. The study used the Comprehensive Air Quality Model with extensions (CAMx) photochemical grid model (PGM) to quantify potential impacts from energy development from BLM field office planning areas. CAMx source apportionment technology was used to track the impacts from multiple (14) different emissions source regions (i.e. field office areas) within one simulation, as well as to assess the cumulative impact of emissions from all source regions combined. The energy development emissions estimates were for the year 2021 for three different development scenarios: (1) low; (2) high; (3) high with emissions mitigation. Impacts on air quality (AQ) including ozone, PM2.5, PM10, NO2, SO2, and air quality related values (AQRVs) such as atmospheric deposition, regional haze and changes in Acid Neutralizing Capacity (ANC) of lakes were quantified, and compared to establish threshold levels. In this presentation, we present a brief summary of the how the emission scenarios were developed, we compare the emission totals for each scenario, and then focus on the ozone impacts for each scenario to assess: (1). the difference in potential ozone impacts under the different development scenarios and (2). to establish the sensitivity of the ozone impacts to different emissions levels. Region-wide ozone impacts will be presented as well as impacts at specific locations with ozone monitors.

Air Quality Management Process Cycle

EPA Pesticide Factsheets

Air quality management are activities a regulatory authority undertakes to protect human health and the environment from the harmful effects of air pollution. The process of managing air quality can be illustrated as a cycle of inter-related elements.

Air Quality Modeling

EPA Pesticide Factsheets

In this technical support document (TSD) EPA describes the air quality modeling performed to support the Environmental Protection Agency’s Transport Rule proposal (now known as the Cross-State Air Pollution Rule).

[Air quality surveillance in France].

PubMed

Téton, S; Robin, D; Genève, C

2009-10-01

As air quality has a direct impact on human health, its monitoring is imperative. In France, this task was entrusted by the government (Air Law of 1996) to organisations with territorial responsibility: the Registered Associations for the Surveillance of Air Quality. The type and level of pollution evolve: from industrial and sulphur pollution in the seventies, to urban and photochemical pollution today and to nanoparticles, pesticides and pollutants in buildings tomorrow. The tools, the skills and the roles of the different people involved in air quality control follow these sometimes rapid transitions in connection with an increasingly precise understanding of the relationship between health and the environment and of the considerable research on the subject. This article describes the mechanisms of air quality monitoring in France.

Process air quality data

NASA Technical Reports Server (NTRS)

Butler, C. M.; Hogge, J. E.

1978-01-01

Air quality sampling was conducted. Data for air quality parameters, recorded on written forms, punched cards or magnetic tape, are available for 1972 through 1975. Computer software was developed to (1) calculate several daily statistical measures of location, (2) plot time histories of data or the calculated daily statistics, (3) calculate simple correlation coefficients, and (4) plot scatter diagrams. Computer software was developed for processing air quality data to include time series analysis and goodness of fit tests. Computer software was developed to (1) calculate a larger number of daily statistical measures of location, and a number of daily monthly and yearly measures of location, dispersion, skewness and kurtosis, (2) decompose the extended time series model and (3) perform some goodness of fit tests. The computer program is described, documented and illustrated by examples. Recommendations are made for continuation of the development of research on processing air quality data.

32 CFR 989.30 - Air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Air quality. 989.30 Section 989.30 National... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.30 Air quality. Section 176(c) of the Clean Air Act..., Air Quality Compliance. 10 10 See footnote 1 to § 989.1. ...

32 CFR 989.30 - Air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 6 2012-07-01 2012-07-01 false Air quality. 989.30 Section 989.30 National... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.30 Air quality. Section 176(c) of the Clean Air Act..., Air Quality Compliance. 10 10 See footnote 1 to § 989.1. ...

32 CFR 989.30 - Air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 6 2014-07-01 2014-07-01 false Air quality. 989.30 Section 989.30 National... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.30 Air quality. Section 176(c) of the Clean Air Act..., Air Quality Compliance. 10 10 See footnote 1 to § 989.1. ...

32 CFR 989.30 - Air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 6 2013-07-01 2013-07-01 false Air quality. 989.30 Section 989.30 National... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.30 Air quality. Section 176(c) of the Clean Air Act..., Air Quality Compliance. 10 10 See footnote 1 to § 989.1. ...

32 CFR 989.30 - Air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 6 2011-07-01 2011-07-01 false Air quality. 989.30 Section 989.30 National... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.30 Air quality. Section 176(c) of the Clean Air Act..., Air Quality Compliance. 10 10 See footnote 1 to § 989.1. ...

Estimating the effects of the transboundary transport and local emissions of atmospheric pollutants in South Korea during KORUS-AQ campaign

NASA Astrophysics Data System (ADS)

Lee, S.; Koo, J. H.; Hong, J.; Choi, M.; Kim, J.; Lim, H.; Holben, B. N.; Eck, T. F.; Ahn, J. Y.; Park, J.; Kim, S. K.

2017-12-01

The air quality of South Korea, located in the east of China, is affected by persistent westerlies, showing the relationship to the emission in upwind region. High aerosol concentration in South Korea is also attributed to local emissions. Particularly, the industrial complex and power plants are concentrated in the Chungcheongnam-do (CN), located by the southwest part of Seoul Metropolitan Area (SMA). In this study, we evaluate the contribution of both the transboundary transport of Chinese pollutants and local emissions in the CN to the air quality in South Korea during Korea-US Air Quality (KORUS-AQ) campaign, 1 May to 12 June in 2016. Based on the information of aerosol optical depth (AOD) obtained from ground-based Aerosol Robotic NETwork (AERONET) sunphotometer and surface in-situ Particulate Matter (PM) measurements at 19 stations, high and low aerosol pollution cases are classified first. Then, 2-day back-trajectories are calculated using National Ocean and Atmospheric Administration (NOAA) HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model at each AERONET site to investigate whether transport pattern is different in accordance with the classified cases about aerosol amounts. As a result, we find the distinct pathway of air-mass transport from eastern China; When high AOD is observed at station located in the western coast of South Korea, air masses are directly transported from Shandong peninsular to the Korean peninsula. In contrast, air masses are mostly transported from northwestern or northern China during the period of low AOD conditions. When PM2.5 detected at SMA sites is greater than Korean government criteria (50 micrograms per cubic meter for 24-hour average PM2.5), SMA sites are mostly affected by air mass flows through the CN area. These results indicate that transport pattern can be different vertically and surface aerosol concentration has different transport pattern from the transport pattern related to the variation of

Air Quality Analysis

EPA Pesticide Factsheets

This site provides information for air quality data analysts inside and outside EPA. Much of the information is in the form of documented analyses that support the review of the national air qualiyt standards.

Improving and monitoring air quality.

PubMed

DuPont, André

2018-05-01

Since the authorization of the Clean Air Act Amendments of 1990, the air quality in the USA has significantly improved because of strong public support. The lessons learned over the last 25 years are being shared with the policy analysts, technical professionals, and scientist who endeavor to improve air quality in their communities. This paper will review how the USA has achieved the "high" standard of air quality that was envisioned in the early 1990s. This document will describe SO 2 gas emission reduction technology and highlight operation of emission monitoring technology. This paper describes the basic process operation of an air pollution control scrubber. A technical review of measures required to operate and maintain a large-scale pollution control system will be described. Also, the author explains how quality assurance procedures in performance of continuous emission monitoring plays a significant role in reducing air pollution.

Asperger syndrome and schizophrenia: Overlap of self-reported autistic traits using the Autism-spectrum Quotient (AQ).

PubMed

Lugnegård, Tove; Hallerbäck, Maria Unenge; Gillberg, Christopher

2015-05-01

In clinical practice, the differential diagnosis of Asperger syndrome (AS) versus schizophrenia can be a challenge. Some self-report instruments-such as the Autism-spectrum Quotient (AQ)-have been portrayed as proxies for the diagnosis of AS. However, it has not been demonstrated to what extent autistic traits-as measured by the AQ-separate AS from schizophrenia. To examine the AS-schizophrenia discriminating ability of the AQ. The AQ is a 50-item self-administered questionnaire (with score range 0-50) for measuring "autistic traits" in adults. Here, it was completed by 136 individuals: 36 with schizophrenic psychosis, 51 with AS and 49 non-clinical comparison cases. A receiver operating characteristic (ROC) analysis for the total AQ score was performed to examine the discriminating power of the instrument. Both individuals with schizophrenia and individuals with AS scored significantly higher on AQ than the non-clinical group. The mean total AQ score (± standard deviation) of the AS group (26.7 ± 8.9; range 9-44) was significantly higher than that of the schizophrenia group (22.7 ± 6.2; range 10-35) (P = 0.041). However, when using the full Likert scale for scoring, the difference did not reach significance. In the ROC analysis of total AQ scores for AS versus schizophrenia, the area under the curve (AUC) was 0.65 (P = 0.02). Although mean AQ scores separated AS and schizophrenia at a group comparison level, significant overlap of AQ scores across the two diagnostic groups clearly reduces the discriminating power of the AQ in the separation of schizophrenia from AS.

Indoor Air Quality in Schools.

ERIC Educational Resources Information Center

Torres, Vincent M.

Asserting that the air quality inside schools is often worse than outdoor pollution, leading to various health complaints and loss of productivity, this paper details factors contributing to schools' indoor air quality. These include the design, operation, and maintenance of heating, ventilating, and air conditioning (HVAC) systems; building…

TEMPO Early Adopters in Air-Quality Forecasting, Planning and Assessment, Pollution Emissions, Health, Agriculture, and Environmental Impacts: Applications and Decision Support

NASA Astrophysics Data System (ADS)

Newchurch, M.; Zavodsky, B.; Chance, K.; Haynes, J.; Lefer, B. L.; Naeger, A.

2016-12-01

The AQ research community has a long legacy of using space-based observations (e.g., Solar Backscatter Ultraviolet Instrument [SBUV], Global Ozone Monitoring Experiment [GOME], Ozone Monitoring Instrument [OMI], and the Ozone Mapping & Profiler Suite [OMPS]) to study atmospheric chemistry. These measurements have been used to observe day-to-day and year-to-year changes in atmospheric constituents. However, they have not been able to capture the diurnal variability of pollution with enough temporal or spatial fidelity and a low enough latency for regular use by operational decision makers. As a result, the operational AQ community has traditionally relied on ground-based (e.g., collection stations, LIDAR) and airborne observing systems to study tropospheric chemistry. In order to maximize its utility for applications and decision support, there is a need to educate the community about the game-changing potential for the geostationary TEMPO mission well ahead of its expected launch date early in the third decade of this millinium. This NASA mission will engage user communities and enable science across the NASA Applied Science Focus Areas of Health and Air Quality, Disasters, Water Resources, and Ecological Forecasting, In addition, topics discussed will provide opportunities for collaborations extending TEMPO applications to future program areas in Agriculture, Weather and Climate (including Numerical Weather Prediction), Energy, and Oceans.

77 FR 52277 - Approval of Air Quality Implementation Plans; California; South Coast Air Quality Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... Quality Implementation Plans; California; South Coast Air Quality Management District; Prevention of... rule. SUMMARY: EPA is proposing approval of a permitting rule submitted for the South Coast Air Quality Management District (District) portion of the California State Implementation Plan (SIP). The State is...

Performance Evaluation of "Low-cost" Sensors for Measuring Gaseous and Particle Air Pollutants: Results from Two Years of Field and Laboratory Testing

NASA Astrophysics Data System (ADS)

Feenstra, B. J.; Polidori, A.; Tisopulos, L.; Papapostolou, V.; Zhang, H.; Pathmanabhan, J.

2016-12-01

In recent years great progress has been made in development of low-cost miniature air quality sensing technologies. Such low-cost sensors offer a prospect of providing a real-time spatially dense information on pollutants, however, the quality of the data produced by these sensors is so far untested. In an effort to inform the general public about the actual performance of commercially available low-cost air quality sensors, in June 2014 the South Coast Air Quality Management District (SCAQMD) has established the Air Quality Sensor Performance Evaluation Center (AQ-SPEC). This program performs a thorough characterization of low-cost sensors under ambient (in the field) and controlled (in the laboratory) conditions. During the field testing, air quality sensors are operated side-by-side with Federal Reference Methods and Federal Equivalent Methods (FRM and FEM, respectively), which are routinely used to measure the ambient concentration of gaseous or particle pollutants for regulatory purposes. Field testing is conducted at two of SCAQMD's existing air monitoring stations, one in Rubidoux and one near the I-710 freeway. Sensors that demonstrate an acceptable performance in the field are brought back to the lab where a "characterization chamber" is used to challenge these devices with known concentrations of different particle and gaseous pollutants under different temperature and relative humidity levels. Testing results for each sensor are then summarized in a technical report and, along with other relevant information, posted online on a dedicated website (www.aqmd.gov/aq-spec) to educate the public about the capabilities of commercially available sensors and their potential applications. During this presentation, the results from two years of field and laboratory testing will be presented. The major strengths and weaknesses of some of the most commonly available particle and gaseous sensors will be discussed.

Indoor Air Quality in Chemistry Laboratories.

ERIC Educational Resources Information Center

Hays, Steve M.

This paper presents air quality and ventilation data from an existing chemical laboratory facility and discusses the work practice changes implemented in response to deficiencies in ventilation. General methods for improving air quality in existing laboratories are presented and investigation techniques for characterizing air quality are…

Enhancing indoor air quality -The air filter advantage.

PubMed

Vijayan, Vannan Kandi; Paramesh, Haralappa; Salvi, Sundeep Santosh; Dalal, Alpa Anil Kumar

2015-01-01

Air pollution has become the world's single biggest environmental health risk, linked to around 7 million deaths in 2012 according to a recent World Health Organisation (WHO) report. The new data further reveals a stronger link between, indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischemic heart disease, as well as between air pollution and cancer. The role of air pollution in the development of respiratory diseases, including acute respiratory infections and chronic obstructive pulmonary diseases, is well known. While both indoor and outdoor pollution affect health, recent statistics on the impact of household indoor pollutants (HAP) is alarming. The WHO factsheet on HAP and health states that 3.8 million premature deaths annually - including stroke, ischemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer are attributed to exposure to household air pollution. Use of air cleaners and filters are one of the suggested strategies to improve indoor air quality. This review discusses the impact of air pollutants with special focus on indoor air pollutants and the benefits of air filters in improving indoor air quality.

Colorado Air Quality Control Regulations and Ambient Air Quality Standards.

ERIC Educational Resources Information Center

Colorado State Dept. of Health, Denver. Div. of Air Pollution Control.

Regulations and standards relative to air quality control in Colorado are defined in this publication. Presented first are definitions of terms, a statement of intent, and general provisions applicable to all emission control regulations adopted by the Colorado Air Pollution Control Commission. Following this, three regulations are enumerated: (1)…

Spatial analysis of concentrations of multiple air pollutants using NASA DISCOVER-AQ aircraft measurements: Implications for exposure assessment.

PubMed

Lee, Hyung Joo; Chatfield, Robert B; Bell, Michelle L

2018-01-01

In recent years, multipollutant approaches have been employed to investigate the association with health outcomes to better represent real-world conditions than more traditional analysis that considers a single pollutant. With regard to the exposure assessment of a mixture of air pollutants, it is critical to understand the spatial variability in multipollutant relations in order to assess their potential health implications. In this study, we investigated the spatial relations of multiple pollutant concentrations (i.e., NO x , NO y , black carbon, carbon monoxide, acetaldehyde, formaldehyde, toluene, xylenes/ethylbenzene, ozone, water-soluble organic carbon, and aerosol extinction) observed from the P-3B aircraft in the 2011 NASA field campaign in Baltimore/Washington D.C. areas during July 2011. The between-pollutant Pearson correlations and Z-scores (calculated from log-transformed concentrations) between near-highways and non-highways and between near-urban centers and non-urban centers varied by pollutant pair and space. We found generally lower correlations between NO x and other pollutants for near-highways (average r = 0.36) than for non-highways (average r = 0.41) and also for non-urban centers (average r = 0.37) than for near-urban centers (average r = 0.41). This indicated that the temporal associations between NO x and health outcomes might be less affected by other pollutants, which were also related to same health outcomes, for near-highways and non-urban centers. The analysis of between-pollutant Z-scores showed varying spatial relations for popular traffic-related pollutants with the Z-score differences of 0.43 (NO x -carbon monoxide), 0.29 (NO x -black carbon), and 0.17 (black carbon-carbon monoxide) between near-highways and non-highways. This result exhibited heterogeneous traffic-related pollutant mixtures with the proximity to highways, potentially leading to the diverse extent of health associations. Furthermore, a mixed effects model

Indoor Air Quality in Schools: Clean Air Is Good Business.

ERIC Educational Resources Information Center

Guarneiri, Michele A.

2003-01-01

Describes the effect of poor indoor air quality (IAQ) on student health, the cost of safeguarding good IAQ, the cause of poor IAQ in schools, how to tell whether a school has an IAQ problem, and how the U.S. Environmental Protection Agency can help schools improve indoor air quality though the use of their free "Indoor Air Quality Tools for…

HD-SP2 Measurements of Black Carbon Containing Aerosols in South Korea during KORUS-AQ

NASA Astrophysics Data System (ADS)

Lamb, K. D.; Perring, A. E.; Ahn, J.; Schwarz, J. P.

2016-12-01

Black carbon (BC) is a light-absorbing aerosol with strong anthropogenic sources that has important climatic and health impacts, both regionally and globally. Materials internally mixed with BC, including water, affect its optical properties and lifetime in the atmosphere, and thus are critical to determining BC's ultimate impacts. The NASA KORUS-AQ campaign during the spring/summer of 2016 was a multi-platform research campaign focused on air quality over South Korea, in a region with particularly high BC emissions and loadings. The NOAA Humidified-Dual Single Particle Soot Photometer (HD-SP2) was deployed on the NASA DC-8 aircraft to measure the optical size and refractory BC content of individual particles under dry and humidified conditions as well as the BC mass mixing ratio. We focus on evaluating BC MMR in the free troposphere up to 400 hPa in the context of previous measurements; assessing the optical impacts of observed internal mixtures with BC at different times of day; and evaluating the contribution of water uptake on BC absorption and atmospheric lifetime over Korea in ambient conditions.

The Economic Value of Air Quality Forecasting

NASA Astrophysics Data System (ADS)

Anderson-Sumo, Tasha

Both long-term and daily air quality forecasts provide an essential component to human health and impact costs. According the American Lung Association, the estimated current annual cost of air pollution related illness in the United States, adjusted for inflation (3% per year), is approximately $152 billion. Many of the risks such as hospital visits and morality are associated with poor air quality days (where the Air Quality Index is greater than 100). Groups such as sensitive groups become more susceptible to the resulting conditions and more accurate forecasts would help to take more appropriate precautions. This research focuses on evaluating the utility of air quality forecasting in terms of its potential impacts by building on air quality forecasting and economical metrics. Our analysis includes data collected during the summertime ozone seasons between 2010 and 2012 from air quality models for the Washington, DC/Baltimore, MD region. The metrics that are relevant to our analysis include: (1) The number of times that a high ozone or particulate matter (PM) episode is correctly forecasted, (2) the number of times that high ozone or PM episode is forecasted when it does not occur and (3) the number of times when the air quality forecast predicts a cleaner air episode when the air was observed to have high ozone or PM. Our collection of data included available air quality model forecasts of ozone and particulate matter data from the U.S. Environmental Protection Agency (EPA)'s AIRNOW as well as observational data of ozone and particulate matter from Clean Air Partners. We evaluated the performance of the air quality forecasts with that of the observational data and found that the forecast models perform well for the Baltimore/Washington region and the time interval observed. We estimate the potential amount for the Baltimore/Washington region accrues to a savings of up to 5,905 lives and 5.9 billion dollars per year. This total assumes perfect compliance with

Parents' Guide to School Indoor Air Quality.

ERIC Educational Resources Information Center

Healthy Schools Network, Inc., Albany, NY.

This parents' guide presents articles on school indoor air pollution, children's health and the symptoms of indoor air pollution, and how schools can improve their air quality. Also included are tips on what to do if the school ignores air quality problems, and some examples of what school districts should be doing to improve their air quality.…

Ambient air pollution and semen quality.

PubMed

Nobles, Carrie J; Schisterman, Enrique F; Ha, Sandie; Kim, Keewan; Mumford, Sunni L; Buck Louis, Germaine M; Chen, Zhen; Liu, Danping; Sherman, Seth; Mendola, Pauline

2018-05-01

Ambient air pollution is associated with systemic increases in oxidative stress, to which sperm are particularly sensitive. Although decrements in semen quality represent a key mechanism for impaired fecundability, prior research has not established a clear association between air pollution and semen quality. To address this, we evaluated the association between ambient air pollution and semen quality among men with moderate air pollution exposure. Of 501 couples in the LIFE study, 467 male partners provided one or more semen samples. Average residential exposure to criteria air pollutants and fine particle constituents in the 72 days before ejaculation was estimated using modified Community Multiscale Air Quality models. Generalized estimating equation models estimated the association between air pollutants and semen quality parameters (volume, count, percent hypo-osmotic swollen, motility, sperm head, morphology and sperm chromatin parameters). Models adjusted for age, body mass index, smoking and season. Most associations between air pollutants and semen parameters were small. However, associations were observed for an interquartile increase in fine particulates ≤2.5 µm and decreased sperm head size, including -0.22 (95% CI -0.34, -0.11) µm 2 for area, -0.06 (95% CI -0.09, -0.03) µm for length and -0.09 (95% CI -0.19, -0.06) µm for perimeter. Fine particulates were also associated with 1.03 (95% CI 0.40, 1.66) greater percent sperm head with acrosome. Air pollution exposure was not associated with semen quality, except for sperm head parameters. Moderate levels of ambient air pollution may not be a major contributor to semen quality. Published by Elsevier Inc.

Significance of solvated electrons (e(aq)-) as promoters of life on earth.

PubMed

Getoff, Nikola

2014-01-01

Based on the present state of knowledge a new hypothesis concerning the origin of life on Earth is presented, and emphasizes the particular significance of solvated electrons (e(aq)(-)). Solvated electrons are produced in seawater, mainly by (40)K radiation and in atmospheric moisture by VUV light, electrical discharges and cosmic ray. Solvated electrons are involved in primary chemical processes and in biological processes. The conversion of aqueous CO2 and CO into simple organic substances, the generation of ammonia from N2 and water, the formation of amines, amino acids and simple proteins under the action of e(aq)(-) has been experimentally proven. Furthermore, it is supposed that the generation of the primitive cell and equilibria of primitive enzymes are also realized due to the strong reducing property of e(aq)(-). The presented hypothesis is mainly founded on recently obtained experimental results. The involvement of e(aq)(-) in such mechanisms, as well as their action as an initiator of life is also briefly discussed.

Indoor airPLUS Videos, Podcasts, Webinars and Interviews

EPA Pesticide Factsheets

The Webinar presentations will help you discover how Indoor airPLUS homes are designed to improve indoor air quality and increase energy efficiency and learn about the key design and construction features included in Indoor airPLUS homes.

Global Air Quality and Climate

NASA Technical Reports Server (NTRS)

Fiore, Arlene M.; Naik, Vaishali; Steiner, Allison; Unger, Nadine; Bergmann, Dan; Prather, Michael; Righi, Mattia; Rumbold, Steven T.; Shindell, Drew T.; Skeie, Ragnhild B.;

Global air quality and climate.

PubMed

Fiore, Arlene M; Naik, Vaishali; Spracklen, Dominick V; Steiner, Allison; Unger, Nadine; Prather, Michael; Bergmann, Dan; Cameron-Smith, Philip J; Cionni, Irene; Collins, William J; Dalsøren, Stig; Eyring, Veronika; Folberth, Gerd A; Ginoux, Paul; Horowitz, Larry W; Josse, Béatrice; Lamarque, Jean-François; MacKenzie, Ian A; Nagashima, Tatsuya; O'Connor, Fiona M; Righi, Mattia; Rumbold, Steven T; Shindell, Drew T; Skeie, Ragnhild B; Sudo, Kengo; Szopa, Sophie; Takemura, Toshihiko; Zeng, Guang

2012-10-07

Emissions of air pollutants and their precursors determine regional air quality and can alter climate. Climate change can perturb the long-range transport, chemical processing, and local meteorology that influence air pollution. We review the implications of projected changes in methane (CH(4)), ozone precursors (O(3)), and aerosols for climate (expressed in terms of the radiative forcing metric or changes in global surface temperature) and hemispheric-to-continental scale air quality. Reducing the O(3) precursor CH(4) would slow near-term warming by decreasing both CH(4) and tropospheric O(3). Uncertainty remains as to the net climate forcing from anthropogenic nitrogen oxide (NO(x)) emissions, which increase tropospheric O(3) (warming) but also increase aerosols and decrease CH(4) (both cooling). Anthropogenic emissions of carbon monoxide (CO) and non-CH(4) volatile organic compounds (NMVOC) warm by increasing both O(3) and CH(4). Radiative impacts from secondary organic aerosols (SOA) are poorly understood. Black carbon emission controls, by reducing the absorption of sunlight in the atmosphere and on snow and ice, have the potential to slow near-term warming, but uncertainties in coincident emissions of reflective (cooling) aerosols and poorly constrained cloud indirect effects confound robust estimates of net climate impacts. Reducing sulfate and nitrate aerosols would improve air quality and lessen interference with the hydrologic cycle, but lead to warming. A holistic and balanced view is thus needed to assess how air pollution controls influence climate; a first step towards this goal involves estimating net climate impacts from individual emission sectors. Modeling and observational analyses suggest a warming climate degrades air quality (increasing surface O(3) and particulate matter) in many populated regions, including during pollution episodes. Prior Intergovernmental Panel on Climate Change (IPCC) scenarios (SRES) allowed unconstrained growth, whereas

30 CFR 75.321 - Air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away flammable...

30 CFR 75.321 - Air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away flammable...

30 CFR 75.321 - Air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away flammable...

30 CFR 75.321 - Air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away flammable...

30 CFR 75.321 - Air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away flammable...

Ozone correlations between mid-tropospheric partial columns and the near-surface at two mid-atlantic sites during the DISCOVER-AQ campaign in July 2011.

PubMed

Martins, Douglas K; Stauffer, Ryan M; Thompson, Anne M; Halliday, Hannah S; Kollonige, Debra; Joseph, Everette; Weinheimer, Andrew J

The current network of ground-based monitors for ozone (O 3 ) is limited due to the spatial heterogeneity of O 3 at the surface. Satellite measurements can provide a solution to this limitation, but the lack of sensitivity of satellites to O 3 within the boundary layer causes large uncertainties in satellite retrievals at the near-surface. The vertical variability of O 3 was investigated using ozonesondes collected as part of NASA's D eriving I nformation on S urface Conditions from CO lumn and VER tically Resolved Observations Relevant to A ir Q uality (DISCOVER-AQ) campaign during July 2011 in the Baltimore, MD/Washington D.C. metropolitan area. A subset of the ozonesonde measurements was corrected for a known bias from the electrochemical solution strength using new procedures based on laboratory and field tests. A significant correlation of O 3 over the two sites with ozonesonde measurements (Edgewood and Beltsville, MD) was observed between the mid-troposphere (7-10 km) and the near-surface (1-3 km). A linear regression model based on the partial column amounts of O 3 within these subregions was developed to calculate the near-surface O 3 using mid-tropospheric satellite measurements from the Tropospheric Emission Spectrometer (TES) onboard the Aura spacecraft. The uncertainties of the calculated near-surface O 3 using TES mid-tropospheric satellite retrievals and a linear regression model were less than 20 %, which is less than that of the observed variability of O 3 at the surface in this region. These results utilize a region of the troposphere to which existing satellites are more sensitive compared to the boundary layer and can provide information of O 3 at the near-surface using existing satellite infrastructure and algorithms.

ComPAQS: a compact concentric UV/visible spectrometer, providing a new tool for air quality monitoring from space

NASA Astrophysics Data System (ADS)

Leigh, Roland J.; Whyte, C.; Cutter, M. A.; Lobb, D. R.; Monks, P. S.

2017-11-01

Under the first phase of the Centre for Earth Observation Instrumentation (CEOI), a breadboard demonstrator of a novel UV/VIS spectrometer has been developed. Using designs from Surrey Satellite Technology Ltd (SSTL) the demonstrator has been constructed and tested at the University of Leicester's Space Research Centre. This spectrometer provides an exceptionally compact instrument for differential optical absorption spectroscopy (DOAS) applications from LEO, GEO, HAP or ground-based platforms. Measurement of atmo spheric compounds with climate change or air quality implications is a key driver for the ground and space-based Earth Observation communities. Techniques using UV/VIS spectroscopy such as DOAS provide measurements of ozone profiles, aerosol optical depth, certain Volatile Organic Compounds, halogenated species, and key air quality parameters including tropospheric nitrogen dioxide. Compact instruments providing the necessary optical performance and spectral resolution are therefore a key enabling technology. The Compact Air Quality Spectrometer (CompAQS) features a concentric arrangement of a spherical meniscus lens, a concave spherical mirror and a suitable curved diffraction grating. This compact design provides efficiency and performance benefits over traditional concepts, improving the precision and spatial resolution available from space borne instruments with limited weight and size budgets. The breadboard spectrometer currently operating at the University of Leicester offers high throughput with a spectral range from 310 to 450 nm at 0.5nm(UV) to 1.0nm (visible) resolution, suitable for DOAS applications. The concentric design is capable of handling high relative apertures, owing to spherical aberration and coma being near zero at all surfaces. The design also provides correction for transverse chromatic aberration and distortion, in addition to correcting for the distortion called `smile' - the curvature of the slit image formed at each

CityAir app: Mapping air-quality perception using people as sensors

NASA Astrophysics Data System (ADS)

Castell, Nuria; Fredriksen, Mirjam; Cole-Hunter, Thomas; Robinson, Johanna; Keune, Hans; Nieuwenhuijsen, Mark; Bartonova, Alena

2016-04-01

Outdoor air pollution is a major environmental health problem affecting all people in developed and developing countries alike. Ambient (outdoor) air pollution in both cities and rural areas was estimated to cause 3.7 million premature deaths worldwide in 2012. In modern society, people are expending an increasing amount of time in polluted urban environments, thus increasing their exposure and associated health responses. Some cities provide information about air pollution levels to their citizens using air quality monitoring networks. However, due to their high cost and maintenance, the density of the monitoring networks is very low and not capable to capture the high temporal and spatial variability of air pollution. Thus, the citizen lacks a specific answer to the question of "how the air quality is in our surroundings". In the framework of the EU-funded CITI-SENSE project the innovative concept of People as Sensors is being applied to the field of outdoor air pollution. This is being done in eight European cities, including Barcelona, Belgrade, Edinburgh, Haifa, Ljubljana, Oslo, Ostrava and Vienna. People as Sensors defines a measurement model, in which measurements are not only taken by hardware sensors, but in which also humans can contribute with their individual "measurements" such as their subjective perception of air quality and other personal observations. In order to collect the personal observations a mobile app, CityAir, has been developed. CityAir allows citizens to rate the air quality in their surroundings with colour at their current location: green if air quality is very good, yellow if air quality is good, orange if air quality is poor and red if air quality is very poor. The users have also the possibility of indicating the source of pollution (i.e. traffic, industry, wood burning) and writing a comment. The information is on-line and accessible for other app users, thus contributing to create an air-quality map based on citizens' perception

Evaluation of ODS-AQ stationary phase for use in capillary electrochromatography.

PubMed

Djordjevic, N M; Fitzpatrick, F; Houdiere, F

2001-04-01

The aim of this study was to evaluate the applicability of ODS-AQ packing material as a stationary phase in capillary electrochromatography (CEC). The electroosmotic flow created on an ODS-AQ stationary phase was measured at different mobile phase compositions and at different column temperatures. It was observed that the electroosmotic flow generated in the column increased by 50% when the temperature of the system was raised from 20 degrees C to 60 degrees C, while all other conditions were kept constant. The electroosmotic flow produced by the ODS-AQ stationary phase was found to be comparable to the flow generated in a column packed with Nucleosil bare-silica material. In addition, a set of polar compounds (D-lysergic acid diethylamide derivatives) was utilized to determine the influence of temperature and mobile phase composition on their chromatographic behavior on an ODS-AQ stationary phase in a CEC mode. A linear relationship between the solute retention factor and column temperatures was seen over the temperature range studied (20 degrees C to 60 degrees C). A quadratic function was used to describe the changes in the solute retention factors with variation of acetonitrile concentration in the mobile phase.

Community Multiscale Air Quality Modeling System (CMAQ)

EPA Pesticide Factsheets

CMAQ is a computational tool used for air quality management. It models air pollutants including ozone, particulate matter and other air toxics to help determine optimum air quality management scenarios.

Sex and STEM Occupation Predict Autism-Spectrum Quotient (AQ) Scores in Half a Million People.

PubMed

Ruzich, Emily; Allison, Carrie; Chakrabarti, Bhismadev; Smith, Paula; Musto, Henry; Ring, Howard; Baron-Cohen, Simon

2015-01-01

This study assesses Autism-Spectrum Quotient (AQ) scores in a 'big data' sample collected through the UK Channel 4 television website, following the broadcasting of a medical education program. We examine correlations between the AQ and age, sex, occupation, and UK geographic region in 450,394 individuals. We predicted that age and geography would not be correlated with AQ, whilst sex and occupation would have a correlation. Mean AQ for the total sample score was m = 19.83 (SD = 8.71), slightly higher than a previous systematic review of 6,900 individuals in a non-clinical sample (mean of means = 16.94) This likely reflects that this big-data sample includes individuals with autism who in the systematic review score much higher (mean of means = 35.19). As predicted, sex and occupation differences were observed: on average, males (m = 21.55, SD = 8.82) scored higher than females (m = 18.95; SD = 8.52), and individuals working in a STEM career (m = 21.92, SD = 8.92) scored higher than individuals non-STEM careers (m = 18.92, SD = 8.48). Also as predicted, age and geographic region were not meaningfully correlated with AQ. These results support previous findings relating to sex and STEM careers in the largest set of individuals for which AQ scores have been reported and suggest the AQ is a useful self-report measure of autistic traits.

The AirQuality SenseBox

NASA Astrophysics Data System (ADS)

Demuth, Dustin; Nuest, Daniel; Bröring, Arne; Pebesma, Edzer

2013-04-01

In the past year, a group of open hardware enthusiasts and citizen scientists had large success in the crowd-funding of an open hardware-based sensor platform for air quality monitoring, called the Air Quality Egg. Via the kickstarter platform, the group was able to collect triple the amount of money than needed to fulfill their goals. Data generated by the Air Quality Egg is pushed to the data logging platform cosm.com, which makes the devices a part of the Internet of Things. The project aims at increasing the participation of citizens in the collection of data, the development of sensors, the operation of sensor stations, and, as data on cosm is publicly available, the sharing, visualization and analysis of data. Air Quality Eggs can measure NO2 and CO concentrations, as well as relative humidity and temperature. The chosen sensors are low-cost and have limited precision and accurracy. The Air Quality Egg consists of a stationary outdoor and a stationary indoor unit. Each outdoor unit will wirelessly transmit air quality measurements to the indoor unit, which forwards the data to cosm. Most recent versions of the Air Quality Egg allow a rough calibration of the gas sensors and on-the-fly conversion from raw sensor readings (impedance) to meaningful air quality data expressed in units of parts per billion. Data generated by these low-cost platforms are not intended to replace well-calibrated official monitoring stations, but rather augment the density of the total monitoring network with citizen sensors. To improve the usability of the Air Quality Egg, we present a new and more advanced concept, called the AirQuality SenseBox. We made the outdoor platform more autonomous and location-aware by adding solarpanels and rechargeable batteries as a power source. The AirQuality SenseBox knows its own position from a GPS device attached to the platform. As a mobile sensor platform, it can for instance be attached to vehicles. A low-cost and low-power wireless chipset

Deep learning architecture for air quality predictions.

PubMed

Li, Xiang; Peng, Ling; Hu, Yuan; Shao, Jing; Chi, Tianhe

2016-11-01

With the rapid development of urbanization and industrialization, many developing countries are suffering from heavy air pollution. Governments and citizens have expressed increasing concern regarding air pollution because it affects human health and sustainable development worldwide. Current air quality prediction methods mainly use shallow models; however, these methods produce unsatisfactory results, which inspired us to investigate methods of predicting air quality based on deep architecture models. In this paper, a novel spatiotemporal deep learning (STDL)-based air quality prediction method that inherently considers spatial and temporal correlations is proposed. A stacked autoencoder (SAE) model is used to extract inherent air quality features, and it is trained in a greedy layer-wise manner. Compared with traditional time series prediction models, our model can predict the air quality of all stations simultaneously and shows the temporal stability in all seasons. Moreover, a comparison with the spatiotemporal artificial neural network (STANN), auto regression moving average (ARMA), and support vector regression (SVR) models demonstrates that the proposed method of performing air quality predictions has a superior performance.

New Federal Air Quality Standards.

ERIC Educational Resources Information Center

Stopinski, O. W.

The report discusses the current procedures for establishing air quality standards, the bases for standards, and, finally, proposed and final National Primary and Secondary Ambient Air Quality Standards for sulfur dioxide, particulate matter, carbon monoxide, nonmethane hydrocarbons, photochemical oxidants, and nitrogen dioxide. (Author/RH)

Assessment of air quality benefits from national air pollution control policies in China. Part II: Evaluation of air quality predictions and air quality benefits assessment

NASA Astrophysics Data System (ADS)

Wang, Litao; Jang, Carey; Zhang, Yang; Wang, Kai; Zhang, Qiang; Streets, David; Fu, Joshua; Lei, Yu; Schreifels, Jeremy; He, Kebin; Hao, Jiming; Lam, Yun-Fat; Lin, Jerry; Meskhidze, Nicholas; Voorhees, Scott; Evarts, Dale; Phillips, Sharon

2010-09-01

Following the meteorological evaluation in Part I, this Part II paper presents the statistical evaluation of air quality predictions by the U.S. Environmental Protection Agency (U.S. EPA)'s Community Multi-Scale Air Quality (Models-3/CMAQ) model for the four simulated months in the base year 2005. The surface predictions were evaluated using the Air Pollution Index (API) data published by the China Ministry of Environmental Protection (MEP) for 31 capital cities and daily fine particulate matter (PM 2.5, particles with aerodiameter less than or equal to 2.5 μm) observations of an individual site in Tsinghua University (THU). To overcome the shortage in surface observations, satellite data are used to assess the column predictions including tropospheric nitrogen dioxide (NO 2) column abundance and aerosol optical depth (AOD). The result shows that CMAQ gives reasonably good predictions for the air quality. The air quality improvement that would result from the targeted sulfur dioxide (SO 2) and nitrogen oxides (NO x) emission controls in China were assessed for the objective year 2010. The results show that the emission controls can lead to significant air quality benefits. SO 2 concentrations in highly polluted areas of East China in 2010 are estimated to be decreased by 30-60% compared to the levels in the 2010 Business-As-Usual (BAU) case. The annual PM 2.5 can also decline by 3-15 μg m -3 (4-25%) due to the lower SO 2 and sulfate concentrations. If similar controls are implemented for NO x emissions, NO x concentrations are estimated to decrease by 30-60% as compared with the 2010 BAU scenario. The annual mean PM 2.5 concentrations will also decline by 2-14 μg m -3 (3-12%). In addition, the number of ozone (O 3) non-attainment areas in the northern China is projected to be much lower, with the maximum 1-h average O 3 concentrations in the summer reduced by 8-30 ppb.

77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-21

...This rule establishes initial air quality designations for most areas in the United States, including areas of Indian country, for the 2008 primary and secondary national ambient air quality standards (NAAQS) for ozone. The designations for several counties in Illinois, Indiana, and Wisconsin that the EPA is considering for inclusion in the Chicago nonattainment area will be designated in a subsequent action, no later than May 31, 2012. Areas designated as nonattainment are also being classified by operation of law according to the severity of their air quality problems. The classification categories are Marginal, Moderate, Serious, Severe, and Extreme. The EPA is establishing the air quality thresholds that define the classifications in a separate rule that the EPA is signing and publishing in the Federal Register on the same schedule as these designations. In accordance with that separate rule, six nonattainment areas in California are being reclassified to a higher classification.

Diagnostics of sources of tropospheric ozone using data assimilation during the KORUS-AQ campaign

NASA Astrophysics Data System (ADS)

Gaubert, B.; Emmons, L. K.; Miyazaki, K.; Buchholz, R. R.; Tang, W.; Arellano, A. F., Jr.; Tilmes, S.; Barré, J.; Worden, H. M.; Raeder, K.; Anderson, J. L.; Edwards, D. P.

2017-12-01

Atmospheric oxidative capacity plays a crucial role in the fate of greenhouse gases and air pollutants as well as in the formation of secondary pollutants such as tropospheric ozone. The attribution of sources of tropospheric ozone is a difficult task because of biases in input parameters and forcings such as emissions and meteorology in addition to errors in chemical schemes. We assimilate satellite remote sensing observations of ozone precursors such as carbon monoxide (CO) and nitrogen dioxide (NO2) in the global coupled chemistry-transport model: Community Atmosphere Model with Chemistry (CAM-Chem). The assimilation is completed using an Ensemble Adjustment Kalman Filter (EAKF) in the Data Assimilation Research Testbed (DART) framework which allows estimates of unobserved parameters and potential constraints on secondary pollutants and emissions. The ensemble will be constructed using perturbations in chemical kinetics, different emission fields and by assimilating meteorological observations to fully assess uncertainties in the chemical fields of targeted species. We present a set of tools such as emission tags (CO and propane), combined with diagnostic analysis of chemical regimes and perturbation of emissions ratios to estimate a regional budget of primary and secondary pollutants in East Asia and their sensitivity to data assimilation. This study benefits from the large set of aircraft and ozonesonde in-situ observations from the Korea-United States Air Quality (KORUS-AQ) campaign that occurred in South Korea in May-June 2016.

Evaluation of the validity of the Autism Spectrum Quotient (AQ) in differentiating high-functioning autistic spectrum disorder from schizophrenia.

PubMed

Naito, Kenichi; Matsui, Yusuke; Maeda, Kiyoshi; Tanaka, Kiwamu

2010-09-30

The aim of this study is to examine the validity of the Autism Spectrum Quotient (AQ) to differentiate high-functioning autistic spectrum disorder (ASD) from schizophrenia (SCH). The AQ was developed by Baron-Cohen et al. to measure autistic traits. In addition to the original AQ items, we created self-administered questions about psychotic symptoms (S-scale). We administered the modified AQ to 51 ASD patients and 46 SCH patients, and we compared these two groups in terms of total AQ score, AQ subscale scores and S-scale score. We applied receiver operating characteristic (ROC) curves to examine the discriminating power of the AQ. The mean total AQ score of the ASD group (32.6; SD=6.8; range: 8-48) was significantly higher than that of the SCH group (21.8; SD=7.4; range: 10-39) (p<0.001). All AQ subscale scores of the ASD group were significantly higher than those of the SCH group. By using a cut-off score of 29 for the AQ total score, we were able to correctly classify 80% of the subjects. At this cut-off, the positive and negative predictive values were 0.83 and 0.78, respectively. Inclusion of additional questions of the S-scale did not increase the power of differentiation. These results indicate that the usefulness of the AQ in differentiating high-functioning ASD from SCH is limited.

Agriculture: Agriculture and Air Quality

EPA Pesticide Factsheets

Information on air emissions from agricultural practices, types of agricultural burning, air programs that may apply to agriculture, reporting requirements, and links to state and other federal air-quality information.

Innovations in projecting emissions for air quality modeling

EPA Science Inventory

Air quality modeling is used in setting air quality standards and in evaluating their costs and benefits. Historically, modeling applications have projected emissions and the resulting air quality only 5 to 10 years into the future. Recognition that the choice of air quality mana...

Indoor air quality: A psychosocial perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boxer, P.A.

1990-05-01

The incidence of indoor air quality problems has increased dramatically over the past decade. Investigation of these problems has yielded a definitive cause in only one third of the cases. Psychosocial factors may play a key role in the development and propagation of symptoms attributed to poor indoor air quality. Guidelines for managing indoor air quality problems from the organizational perspective are based upon psychosocial principles and elements of risk perception.

Clean air through transportation : challenges in meeting national air quality standards

DOT National Transportation Integrated Search

1993-08-01

This report, required by Section 108(f)(3) of the Clean Air Act, as amended in 1990, addresses the issues of motor vehicles and air quality. The report discusses the challenges faced in attempting to improve air quality through transportation program...

Urban and Industrial VOC Emissions in the Seoul Metropolitan Area and Surrounding Region during the KORUS-AQ Field Study

NASA Astrophysics Data System (ADS)

Simpson, I. J.; Blake, D. R.; Blake, N. J.; Meinardi, S.; Barletta, B.; Hughes, S.; Vizenor, N.; Emmons, L. K.; Barré, J.; Woo, J. H.; Kim, J.; Schroeder, J.; Knote, C. J.; Fried, A.; Armin, W.; Min, K. E.; Jeong, S.

2017-12-01

The Korea-United States Air Quality Study (KORUS-AQ) took place in May and June, 2016 to better understand air pollution in Korea. During the campaign 2650 whole air samples were collected aboard the NASA DC-8 aircraft and analyzed for more than 80 C1-C10 volatile organic compounds (VOCs), including alkanes, aromatics, alkenes, halocarbons and organic nitrates. Approximately 300 samples were collected at low altitude (< 1 km) over the Seoul Metropolitan Area (SMA), and 20 downwind of the Daesan industrial facility southwest of Seoul. The Seoul and Daesan samples showed distinct chemical signals. Air in the SMA was rich in VOCs such as ethane, propane, toluene, ethyne and n-butane, reflecting a mix of source influences including natural gas, liquefied petroleum gas, vehicle exhaust and industrial solvents. Aromatics (e.g., toluene, xylenes) and alkenes (e.g., isoprene) were strong contributors to OH reactivity in the SMA. The Daesan plumes were rich in VOCs such as ethene, benzene and n-hexane, and at least 25 VOCs showed their highest mixing ratios of the mission in these plumes. Because some of the emitted industrial compounds are known carcinogens (e.g., benzene, 1,3-butadiene), more work is needed to assess potential long-term health effects for facility workers and local residents. Ongoing work includes further clarifying specific source influences in the SMA, assessing emission inventories and the contribution of individual VOCs to ozone production, and linking the airborne data to ground-based measurements.

78 FR 47191 - Air Quality Designations for the 2010 Sulfur Dioxide (SO2) Primary National Ambient Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-05

... Air Quality Designations for the 2010 Sulfur Dioxide (SO[bdi2]) Primary National Ambient Air Quality... air quality designations for certain areas in the United States for the 2010 primary Sulfur Dioxide... of this document? III. What is sulfur dioxide? IV. What is the 2010 SO 2 NAAQS and what are the...

Evaluation of improved operational standard tropospheric NO2 retrievals from Ozone Monitoring Instrument using in situ and surface-based NO2 observations

NASA Astrophysics Data System (ADS)

Celarier, E. A.; Lamsal, L.; Krotkov, N. A.; Bucsela, E. J.; Herman, J. R.; Dickerson, R. R.; He, H.; Brent, L. C.; Retscher, C.; Swartz, W. H.; Gleason, J. F.

2011-12-01

Nitrogen oxides are key actors in air quality and climate change. Column observations of tropospheric NO2 from the nadir-veiwing satellite sensors have been widely used to understand sources and chemistry of NOx. We have implemented several improvements to the operational algorithm developed at NASA GSFC and retrieved tropospheric NO2. Here we evaluate the new product using in situ surface measurements at the SEARCH, AQS/EPA, and NAPS networks, in situ aircraft (DISCOVER-AQ and RAMMPP), and ground-based PANDORA and DOAS measurements. The agreement among these data is within the uncertainty of measurements. The new OMI tropospheric NO2 product available at high spatial resolution is valuable to evaluate chemical transport models, to examine spatial and temporal pattern of NOx emissions, to provide top-down constraints to surface NOx emissions, and to estimate NOx lifetimes.

Time to harmonize national ambient air quality standards.

PubMed

Kutlar Joss, Meltem; Eeftens, Marloes; Gintowt, Emily; Kappeler, Ron; Künzli, Nino

2017-05-01

The World Health Organization has developed ambient air quality guidelines at levels considered to be safe or of acceptable risk for human health. These guidelines are meant to support governments in defining national standards. It is unclear how they are followed. We compiled an inventory of ambient air quality standards for 194 countries worldwide for six air pollutants: PM 2.5 , PM 10 , ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide. We conducted literature and internet searches and asked country representatives about national ambient air quality standards. We found information on 170 countries including 57 countries that did not set any air quality standards. Levels varied greatly by country and by pollutant. Ambient air quality standards for PM 2.5 , PM 10 and SO 2 poorly complied with WHO guideline values. The agreement was higher for CO, SO 2 (10-min averaging time) and NO 2 . Regulatory differences mirror the differences in air quality and the related burden of disease around the globe. Governments worldwide should adopt science based air quality standards and clean air management plans to continuously improve air quality locally, nationally, and globally.

40 CFR 52.2682 - Air quality surveillance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Air quality surveillance. 52.2682... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Guam § 52.2682 Air quality... Pollution Control Standards and Regulations” (buffer zones—air quality sampling) are not in conformance with...

40 CFR 52.2682 - Air quality surveillance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Air quality surveillance. 52.2682... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Guam § 52.2682 Air quality... Pollution Control Standards and Regulations” (buffer zones—air quality sampling) are not in conformance with...

40 CFR 52.2682 - Air quality surveillance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Air quality surveillance. 52.2682... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Guam § 52.2682 Air quality... Pollution Control Standards and Regulations” (buffer zones—air quality sampling) are not in conformance with...

40 CFR 52.2682 - Air quality surveillance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Air quality surveillance. 52.2682... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Guam § 52.2682 Air quality... Pollution Control Standards and Regulations” (buffer zones—air quality sampling) are not in conformance with...

40 CFR 52.2682 - Air quality surveillance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Air quality surveillance. 52.2682... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Guam § 52.2682 Air quality... Pollution Control Standards and Regulations” (buffer zones—air quality sampling) are not in conformance with...

Air Quality Criteria for Ozone and Related Photochemical ...

EPA Pesticide Factsheets

In February 2006, EPA released the final document, Air Quality Criteria for Ozone and Other Photochemical Oxidants. Tropospheric or surface-level ozone (O3) is one of six major air pollutants regulated by National Ambient Air Quality Standards (NAAQS) under the U.S. Clean Air Act. As mandated by the Clean Air Act, the U.S. Environmental Protection Agency (EPA) must periodically review the scientific bases (or criteria) for the various NAAQS by assessing newly available scientific information on a given criteria air pollutant. This document, Air Quality Criteria for Ozone and Other Photochemical Oxidants, is an updated revision of the 1996 Ozone Air Quality Criteria Document (O3 AQCD) that provided scientific bases for the current O3 NAAQS set in 1997. The Clean Air Act mandates periodic review of the National Ambient Air Quality Standards (NAAQS) for six common air pollutants, also referred to as criteria pollutants, including ozone.

Air Quality Criteria for Particulate Matter.

ERIC Educational Resources Information Center

National Air Pollution Control Administration (DHEW), Washington, DC.

To assist states in developing air quality standards, this book offers a review of literature related to atmospheric particulates and the development of criteria for air quality. It not only summarizes the current scientific knowledge of particulate air pollution, but points up the major deficiencies in that knowledge and the need for further…

BASIS FOR PRIMARY AIR QUALITY CRITERIA AND STANDARDS

EPA Science Inventory

The Environmental Criteria and Assessment Office and the Office of Air Quality Planning and Standards are charged with responsibility for reviewing and assessing air quality criteria and air quality standards, respectively. Since adoption of the 1977 Clean Air Act Amendments, the...

Enhancing indoor air quality –The air filter advantage

PubMed Central

Vijayan, Vannan Kandi; Paramesh, Haralappa; Salvi, Sundeep Santosh; Dalal, Alpa Anil Kumar

2015-01-01

Air pollution has become the world's single biggest environmental health risk, linked to around 7 million deaths in 2012 according to a recent World Health Organisation (WHO) report. The new data further reveals a stronger link between, indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischemic heart disease, as well as between air pollution and cancer. The role of air pollution in the development of respiratory diseases, including acute respiratory infections and chronic obstructive pulmonary diseases, is well known. While both indoor and outdoor pollution affect health, recent statistics on the impact of household indoor pollutants (HAP) is alarming. The WHO factsheet on HAP and health states that 3.8 million premature deaths annually - including stroke, ischemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer are attributed to exposure to household air pollution. Use of air cleaners and filters are one of the suggested strategies to improve indoor air quality. This review discusses the impact of air pollutants with special focus on indoor air pollutants and the benefits of air filters in improving indoor air quality. PMID:26628762

Evaluating commercial marine emissions and their role in air quality policy using observations and the CMAQ model

NASA Astrophysics Data System (ADS)

Ring, Allison M.; Canty, Timothy P.; Anderson, Daniel C.; Vinciguerra, Timothy P.; He, Hao; Goldberg, Daniel L.; Ehrman, Sheryl H.; Dickerson, Russell R.; Salawitch, Ross J.

2018-01-01

We investigate the representation of emissions from the largest (Class 3) commercial marine vessels (c3 Marine) within the Community Multiscale Air Quality (CMAQ) model. In present emissions inventories developed by the United States Environmental Protection Agency (EPA), c3 Marine emissions are divided into off-shore and near-shore files. Off-shore c3 Marine emissions are vertically distributed within the atmospheric column, reflecting stack-height and plume rise. Near-shore c3 Marine emissions, located close to the US shoreline, are erroneously assumed to occur only at the surface. We adjust the near-shore c3 Marine emissions inventory by vertically distributing these emissions to be consistent with the off-shore c3 Marine inventory. Additionally, we remove near-shore c3 Marine emissions that overlap with off-shore c3 Marine emissions within the EPA files. The CMAQ model generally overestimates surface ozone (O3) compared to Air Quality System (AQS) site observations, with the largest discrepancies occurring near coastal waterways. We compare modeled O3 from two CMAQ simulations for June, July, and August (JJA) 2011 to surface O3 observations from AQS sites to examine the efficacy of the c3 Marine emissions improvements. Model results at AQS sites show average maximum 8-hr surface O3 decreases up to ∼6.5 ppb along the Chesapeake Bay, and increases ∼3-4 ppb around Long Island Sound, when the adjusted c3 Marine emissions are used. Along with the c3 Marine emissions adjustments, we reduce on-road mobile NOX emissions by 50%, motivated by work from Anderson et al. 2014, and reduce the lifetime of the alkyl nitrate species group from ∼10 days to ∼1 day based on work by Canty et al. 2015, to develop the ;c3 Science; model scenario. Simulations with these adjustments further improve model representation of the atmosphere. We calculate the ratio of column formaldehyde (HCHO) and tropospheric column nitrogen dioxide (NO2) using observations from the Ozone

The impact of the observation nudging and nesting on the simulated meteorology and ozone concentrations from WRF-SMOKE-CMAQ during DISCOVER-AQ 2013 Texas campaign

NASA Astrophysics Data System (ADS)

Choi, Y.; Li, X.; Czader, B.

2014-12-01

Three WRF simulations for the DISCOVER-AQ 2013 Texas campaign period (30 days in September) are performed to characterize uncertainties in the simulated meteorological and chemical conditions. These simulations differ in domain setup, and in performing observation nudging in WRF runs. There are around 7% index of agreement (IOA) gain in temperature and 9-12% boost in U-WIND and V-WIND when the observational nudging is employed in the simulation. Further performance gain from nested domains over single domain is marginal. The CMAQ simulations based on above WRF setups showed that the ozone performance slightly improved in the simulation for which objective analysis (OA) is carried out. Further IOA gain, though quite limited, is achieved with nested domains. This study shows that the high ozone episodes during the analyzed time periods were associated with the uncertainties of the simulated cold front passage, chemical boundary condition and small-scale temporal wind fields. All runs missed the observed high ozone values which reached above 150 ppb in La Porte on September 25, the only day with hourly ozone over 120 ppb. The failure is likely due to model's inability to catch small-scale wind shifts in the industrial zone, despite better wind directions in the simulations with nudging and nested domains. This study also shows that overestimated background ozone from the southerly chemical boundary is a critical source for the model's general overpredictions of the ozone concentrations from CMAQ during September of 2013. These results of this study shed a light on the necessity of (1) capturing the small-scale winds such as the onsets of bay-breeze or sea-breeze and (2) implementing more accurate chemical boundary conditions to reduce the simulated high-biased ozone concentrations. One promising remedy for (1) is implementing hourly observation nudging instead of the standard one which is done every three hours.

75 FR 71033 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-22

.... These include damage to the central nervous system, cardiovascular function, kidneys, immune system, and... growth); (5) Meteorology (weather/transport patterns); (6) Geography/topography (mountain ranges or other... Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards AGENCY...

Forest ecosystem services: Carbon and air quality

Treesearch

David J. Nowak; Neelam C. Poudyal; Steve G. McNulty

2017-01-01

Forests provide various ecosystem services related to air quality that can provide substantial value to society. Through tree growth and alteration of their local environment, trees and forests both directly and indirectly affect air quality. Though forests affect air quality in numerous ways, this chapter will focus on five main ecosystem services or disservices...

Instrumentation for air quality measurements.

NASA Technical Reports Server (NTRS)

Loewenstein, M.

1973-01-01

Comparison of the new generation of air quality monitoring instruments with some more traditional methods. The first generation of air quality measurement instruments, based on the use of oxidant coulometric cells, nitrogen oxide colorimetry, carbon monoxide infrared analyzers, and other types of detectors, is compared with new techniques now coming into wide use in the air monitoring field and involving the use of chemiluminescent reactions, optical absorption detectors, a refinement of the carbon monoxide infrared analyzer, electrochemical cells based on solid electrolytes, and laser detectors.

40 CFR 52.1234 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1234 Section 52.1234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1884 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.499 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1180 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2827 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1689 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1689 Section 52.1689 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2676 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2779 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2729 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2497 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1603 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1165 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality. The...

40 CFR 52.499 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1884 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1165 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality. The...

40 CFR 52.1165 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality. The...

40 CFR 52.1180 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2729 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1884 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2779 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.499 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1603 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1234 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.1234 Section 52.1234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2497 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2497 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1603 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1884 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2676 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1603 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.499 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2676 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2779 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1234 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.1234 Section 52.1234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2676 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1165 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality. The...

40 CFR 52.2827 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1165 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality. The...

40 CFR 52.1180 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2676 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2497 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.499 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2729 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1180 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2497 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1234 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.1234 Section 52.1234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2827 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1180 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1884 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2729 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2729 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2827 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2827 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1234 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.1234 Section 52.1234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2779 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.2779 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

40 CFR 52.1603 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality. The...

Strength of smoke-free air laws and indoor air quality.

PubMed

Lee, Kiyoung; Hahn, Ellen J; Robertson, Heather E; Lee, Seongjik; Vogel, Suzann L; Travers, Mark J

2009-04-01

Smoke-free air laws have been implemented in many Kentucky communities to protect the public from the harmful effects of secondhand smoke exposure. The impact of different strengths of smoke-free air laws on indoor air quality was assessed. Indoor air quality in hospitality venues was assessed in seven communities before and after comprehensive smoke-free air laws and in two communities only after partial smoke-free air laws. One community was measured three times: before any smoke-free air law, after the initial partial law, and after the law was strengthened to cover all workplaces and public places with few exemptions. Real-time measurements of particulate matters with 2.5 mum aerodynamic diameter or smaller (PM(2.5)) were obtained. When comprehensive smoke-free air laws were implemented, indoor PM(2.5) concentrations decreased significantly from 161 to 20 microg/m3. In one community that implemented a comprehensive smoke-free law after initially passing a partial law, indoor PM(2.5) concentrations were 304 microg/m3 before the law, 338 microg/m3 after the partial law, and 9 microg/m3 after the comprehensive law. The study clearly demonstrated that partial smoke-free air laws do not improve indoor air quality. A significant linear trend indicated that PM(2.5) levels in the establishments decreased with fewer numbers of burning cigarettes. Only comprehensive smoke-free air laws are effective in reducing indoor air pollution from secondhand tobacco smoke.

The Value of Clean Air: Comparing Discounting of Delayed Air Quality and Money Across Magnitudes.

PubMed

Berry, Meredith S; Friedel, Jonathan E; DeHart, William B; Mahamane, Salif; Jordan, Kerry E; Odum, Amy L

2017-06-01

The detrimental health effects of exposure to air pollution are well established. Fostering behavioral change concerning air quality may be challenging because the detrimental health effects of exposure to air pollution are delayed. Delay discounting, a measure of impulsive choice, encapsulates this process of choosing between the immediate conveniences of behaviors that increase pollution and the delayed consequences of prolonged exposure to poor air quality. In Experiment 1, participants completed a series of delay-discounting tasks for air quality and money. We found that participants discounted delayed air quality more than money. In Experiment 2, we investigated whether the common finding that large amounts of money are discounted less steeply than small amounts of money generalized to larger and smaller improvements in air quality. Participants discounted larger improvements in air quality less steeply than smaller improvements, indicating that the discounting of air quality shares a similar process as the discounting of money. Our results indicate that the discounting of delayed money is strongly related to the discounting of delayed air quality and that similar mechanisms may be involved in the discounting of these qualitatively different outcomes. These data are also the first to demonstrate the malleability of delay discounting of air quality, and provide important public health implications for decreasing delay discounting of air quality.

40 CFR 52.632 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.793 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.738 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.738 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.632 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.793 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.632 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.632 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.738 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.632 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.738 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.738 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.793 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01

... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.793 - Significant deterioration of air quality.

Code of Federal Regulations, 2013 CFR

2013-07-01

... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.793 - Significant deterioration of air quality.

Code of Federal Regulations, 2014 CFR

2014-07-01

... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The provisions...

40 CFR 52.432 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.432 Section 52.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulation for preventing significant deterioration of air quality. The provisions of...

40 CFR 52.96 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

... quality. 52.96 Section 52.96 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Alaska Department of Environmental Conservation Air Quality... deterioration of air quality. (b) The requirements of sections 160 through 165 of the Clean Air Act are not met...

40 CFR 52.432 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

... quality. 52.432 Section 52.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulation for preventing significant deterioration of air quality. The provisions of...

40 CFR 52.432 - Significant deterioration of air quality.

Code of Federal Regulations, 2012 CFR

2012-07-01