The NARSTO_EPA_SS_HOUSTON_NO3_SO4_C_DATA files contain continuous measurements of PM2.5 nitrate, PM2.5 sulfate, and PM2.5 carbon collected during August 12, 2000 through November 5, 2001 at the Aldine, Deer Park, and LaPorte Houston Supersite monitoring locations. Nitrate measurements were collected using the R&P 8400N Method. Sulfate and carbon measurements were collected using the Prototype ADI Particulate Sulfate and Carbon Monitor Method.The Houston Supersite is one of several Supersites that was established in urban areas within the United States by the U.S. Environmental Protection Agency (EPA) to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The overall goals were to characterize the composition and identify the sources of particulate matter in Southeastern Texas, to develop and test new methods for characterizing fine particulate matter, and to collect data on the physical and chemical characterization of fine particulate matter that can be used to support exposure and health effects studies.NARSTO (formerly North American Research Strategy for Tropospheric Ozone) is a public/private partnership, whose membership spans government, the utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission is to coordinate and enhance policy-relevant scientific research and assessment of tropospheric pollution behavior; activities provide input for science-based decision-making and determination of workable, efficient, and effective strategies for local and regional air-pollution management. Data products from local, regional, and international monitoring and research programs are available.

The NARSTO_EPA_SS_ST_LOUIS_AIR_CHEM_PM_MET_DATA were obtained between April 11, 2001 and July 21, 2003 during the St. Louis - Midwest Supersite program.The overall goal of the St. Louis - Midwest Supersite was to conduct aerosol physical and chemical measurements needed by the health effects community, the atmospheric science community and the regulatory community to properly assess the impact of particulate matter exposure on human health and to develop control strategies to mitigate these effects. Metropolitan St. Louis is a major population center well isolated from other urban centers of even moderate size, and is impacted by both distant and local sources. Local industry includes manufacturing,refining, and chemical plants. St. Louis is climatologically representative of the country's eastern interior, affected by a wide range of synoptic weather patterns and free of localized influences from the Great Lakes, Ocean, Gulf, and mountains. It accordingly provides an ideal environment for studying the sources, transport, and properties of ambient particles.The initial data types included:1) 5-minute PM 2.5 black carbon (880 nm) and uv-absorbing carbon (370 nm) measured by a Magee Scientific Aethalometer (Model AE-21).2) 1-hour PM 2.5 elemental carbon and blank-corrected organic carbon from semicontinuous thermo-optical analysis by the ACE-ASIA method.3) 24-hour PM 2.5 elemental carbon and organic carbon (both blank-corrected) from integrated filter with offline thermo-optical analysis by the ACE-ASIA method.4) 30-minute PM 2.5 metal composition from samples collected with a Semicontinuous Elements in Aerosol Sampler (SEAS) II.5) 5-minute meteorological data (wind, temperature, RH, solar radiation, atmospheric pressure, and precipitation) measured with a Climatronics anemometer, wind vane, thermocouple, lithium chloride sensor, pyranometer, barometer, and tipping bucket.6) 24-hour PM 1.0 filter mass concentration measured by sharp cut cyclone and gravimetric analysis.7) 1-hour PM 2.5 mass measured by an Andersen Continuous Ambient Mass Monitoring System (CAMMS).8) 24-hour PM 2.5 and PM 10 filter mass by Harvard Impactors and laboratory gravimetric analysis.The U.S. EPA Particulate Matter (PM) Supersites Program was an ambient air monitoring research program designed to provide information of value to the atmospheric sciences, and human health and exposure research communities. Eight geographically diverse projects were chosen to specifically address these EPA research priorities: (1) to characterize PM, its constituents, precursors, co-pollutants, atmospheric transport, and its source categories that affect the PM in any region; (2) to address the research questions and scientific uncertainties about PM source-receptor and exposure-health effects relationships; and (3) to compare and evaluate different methods of characterizing PM including testing new and emerging measurement methods. NARSTO (formerly North American Research Strategy for Tropospheric Ozone) is a public/private partnership, whose membership spans government, the utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission is to coordinate and enhance policy-relevant scientific research and assessment of tropospheric pollution behavior; activities provide input for science-based decision-making and determination of workable, efficient, and effective strategies for local and regional air-pollution management. Data products from local, regional, and international monitoring and research programs are available.

The NARSTO_EPA_SS_HOUSTON_TEXAQS2000_PM_FTIR measurement data consist of absolute absorbance areas for organonitrates, sulfate, aliphatic carbon and carbonyl compounds for size segregated particulate matter collected using a Herring Low Pressure Impactor (LPI). These data were collected during August and September 2000 at the Houston PM Supersite locations (LaPorte, HRM3, and Aldine) during the Texas Air Quality Study 2000 (TexAQS).The Houston Supersite is one of several Supersites that was established in urban areas within the United States by the U.S. Environmental Protection Agency (EPA) to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The overall goals were to characterize the composition and identify the sources of particulate matter in Southeastern Texas, to develop and test new methods for characterizing fine particulate matter, and to collect data on the physical and chemical characterization of fine particulate matter that can be used to support exposure and health effects studies.NARSTO (formerly North American Research Strategy for Tropospheric Ozone) is a public/private partnership, whose membership spans government, the utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission is to coordinate and enhance policy-relevant scientific research and assessment of tropospheric pollution behavior; activities provide input for science-based decision-making and determination of workable, efficient, and effective strategies for local and regional air-pollution management. Data products from local, regional, and international monitoring and research programs are available.

NARSTO_EPA_SS_PITTSBURGH_PM_COMPOSITION_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Pittsburgh Particulate Matter (PM) Composition Data. It was obtained between June 30 and September 1, 2001 during the Pittsburgh Air Quality Study (PAQS). The data set provides PM Composition Data of the following types:1) PM2.5 nitrate and PM2.5 sulfate.2) Semi-Continuous Organic and Elemental Carbon Measurements.3) Air concentrations of water soluble PM2.5 aerosol species and water soluble gases, as measured with the CMU steam sampler - IC combination.4) Manual filter-based PM2.5 element measurements from microwave decomposition of filters followed by Inductively Coupled Plasma Mass Spectrometer analysis.5) Manual filter-based PM10 element measurements from microwave decomposition of filters and Inductively Coupled Plasma Mass Spectrometer analysis.6) Manual filter-based PM2.5 inorganic composition with analysis performed using ion chromatography.7) Manual filter-based PM2.5 organic and elemental carbon measurements with analysis performed using a Thermal Optical Transmission carbon analyzer.8) Measurements of PM composition size distributions using a MOUDI cascade impactor.9) PM2.5 organic and elemental carbon concentrations from an activated carbon denuder/quartz filter/charcoal impregnated fiber filter backup combination. Quartz filters analyzed using a Thermal/Optical transmittance carbon analyzer.10) Fog chemistry dataPAQS, along with the Pittsburgh Supersite Program, was a comprehensive, multi-disciplinary investigation to characterize the ambient PM in the Pittsburgh region, to improve understanding the links between ambient PM and public health, and to develop new instrumentation for PM measurements. The Pittsburgh Supersite was designed to achieve several objectives: to determine the physical and chemical characteristics of PM in the Pittsburgh region; to develop and evaluate the next generation of atmospheric aerosol monitoring techniques; to update emission profiles for important regional sources; to quantify the impact of the various sources on the local PM concentrations; and to predict changes in the PM characteristics due to proposed changes in emissions. The last objective was based on concurrent modeling studies and was designed to support the development of regulations. These objectives were addressed through four components of the research: (1) ambient monitoring at a central site and a set of satellite sites in the region; (2) an instrument development and evaluation study; (3) a data analysis and synthesis component; and (4) a comprehensive modeling component.The central supersite was located on a grassy hill in a large urban park adjacent to the Carnegie Mellon University campus, approximately 6km east of downtown Pittsburgh. It was separated from the city in the predominant upwind direction (south and west) by roughly 1km of parkland. It was at least several hundred meters from any other major source of air pollution: the site was positioned approximately 50m past the end of a dead end street, and several hundred meters from the nearest heavily traveled street. Five additional sites were operated as Satellite sites to character the spatial variation of the PM. The measurement campaign lasted for 14 months (July 2001-September 2002). Intensive monitoring was performed during two periods, from 1 July to 3 August 2001 (ESP01) and 1 January to 15 January, 2002 (ESP02). Baseline monitoring was conducted for the rest of the study. Baseline measurements included daily filter samples for fine particle mass and composition (OC/EC, major ions, elemental composition). The U.S. EPA PM Supersites Program was an ambient air monitoring research program designed to provide information of value to the atmospheric sciences, and human health and exposure research communities. Eight geographically diverse projects were chosen to specifically address these

NARSTO_PAC2001_LANGLEY_GAS_PM_MET_DATA was obtained between August 8 and September 2, 2001 during the Pacific 2001 Air Quality Study (PAC2001).The Langley Ecole Lochiel (LEL) site was at 49.0289 N and -122.6025 W and at 90m above sea level (a.s.l). The site was surrounded by hobby farms and by relatively few country roads that are lined with both coniferous and deciduous trees, with little change in terrain heights within a radius of 15 km. Nontraditional agricultural practices, such as mushroom and chicken farming and small orchards, are common within this radius of the site. The nearest small urban center, Langley, is about 6 km north of the site. The site was approximately 10 km to the major expressways of Highway 1 in Canada and I-5 in the US and was approximately 6km to Highway 1A in Canada. Particle sampling was done in the center of an unobstructed field of approximately 30-50m2 about 2.5m from ground. On-site measurements were conducted from five temporary labs with inlets about 5m above ground. Measurements at this site, from August 13th to 31st, were intended to address the unknowns related to particles and ozone, with an emphasis on the transition from the urban mix to a suburban/rural setting, particularly the impact of agricultural sources on the particulate matter formation and evolution. Similar to the instrumentation package at Slocan Park site, the instrumentation package includes measurements in five categories.1) Measurements related to the precursors of fine PM and the oxidation environment in which the fine PM is formed. 2) Measurements related to the characterization of fine PM and the evolution process of PM.3) Measurements related to the emission of fine PM and its precursors in the valley.4) Measurements related to the mapping of fine PM horizontal and vertical distribution in the valley.5) Measurements of meteorological parameters in the valley. Measurements included detailed gas phase measurements of NOx=NOy (total and speciated), CO, O3, SO2, VOCs, OVOCs, carbonyls, NH3, HOx, and NH3 intended for a detailed understanding of the oxidation environment and chemical processes in which both O3 and secondary particulate matter are formed. Detailed measurements were made on size distributed inorganic ionic components, organic carbon, elemental carbon, and mass from 0.05 to 18 mm AD twice a day. High-time resolution measurements using a second AMS were made, measuring the size distribution of inorganic species and homologues of organic species from 0.06 to 0.7 mm. Detailed organic carbon speciation measurements, carbon isotope characterization, sulfur isotope characterization, and amorphous carbon were made for particles 2.5 mm on 10-h day samples collected twice daily. The gas-particle partitioning of semi-volatile organic compounds was studied using a Hi-cap denuder sampling system and detailed lab organic analyses. Continuous mass measurements for particles 2.5 mm were made using a tapered element oscillating microbalance (TEOM)with a diffusion dryer on the inlet. Particle number size distributions were measured from 0.01 to 3 mm using a DMA and an optical probe. Hygroscopic properties of particles were measured at two particle sizes using two DMAs in tandem. For NH3, HNO2, HNO3, HCHO, and PM 2.5 mm mass measurements and the particle chemical size distributions, more than one technique were deployed at this site. The multiple measurements of these species provided a test of the performance and validation of the different techniques and ensure that instrument biases were corrected. They also provide complementing data of different characteristics, such as better sensitivities versus time resolution. The diurnal evolution of the boundary layer height was studied using a scanning LIDAR that scanned the north, east and west quadrants. Radiation measurements, both UV and visible, were done using an Eppley and a CIMEL sun photometer. Vertical distribution of certain parameters, such as O3 and meteorological