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NARSTO EPA Supersite (SS) Fresno, Aethalometer Multi-Wavelength Carbon Data
NARSTO_EPA_SS_FRESNO_AETHALOM_MULTI_WL_CARBON is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Aethalometer Multi-Wavelength Carbon Data product. This data was obtained between May 1999 and December 2006 at the Fresno supersite. A multiwavelength aethalometer (Model AE30S) operated at the Fresno supersite from May 12, 1999 to December 31, 2006. The collected aerosol sample was illuminated with light from seven light emitting diodes at wavelengths of 370, 470, 520, 590, 660, 880, and 950 nm. Aerosol samples were collected for five minute periods. The air sample was collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 um and less. The concentration of black carbon corresponded to the 880 nm measurement. The black carbon equivalents at the other six wavelengths were also determined.The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
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NARSTO EPA Supersite (SS) Fresno, Aethalometer Multi-Wavelength Carbon Data
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NARSTO_EPA_SS_FRESNO_AETHALOM_MULTI_WL_CARBON is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Aethalometer Multi-Wavelength Carbon Data product. This data was obtained between May 1999 and December 2006 at the Fresno supersite. A multiwavelength aethalometer (Model AE30S) operated at the Fresno supersite from May 12, 1999 to December 31, 2006. The collected aerosol sample was illuminated with light from seven light emitting diodes at wavelengths of 370, 470, 520, 590, 660, 880, and 950 nm. Aerosol samples were collected for five minute periods. The air sample was collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 um and less. The concentration of black carbon corresponded to the 880 nm measurement. The black carbon equivalents at the other six wavelengths were also determined. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Elemental Carbon in 2.5 um Aerosol Fraction Data
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NARSTO_EPA_SS_FRESNO_EC_PM25_FRACTION is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Elemental Carbon in 2.5 um Aerosol Fraction Data product. This data set contains the measurements taken with a single and dual wavelength aethalometer. The single wavelength aethalometer (model AE14) was operated at the Fresno supersite from December 17, 1999 to September 27, 2002. This instrument used a broad spectrum incandescent lamp to illuminate the collected aerosol. Aerosol samples were collected for five minute periods. The air sample was collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 m or less. A single concentration of black carbon was determined for each five minute period. A dual-wavelength aethalometer (model AE21) operated at the Fresno supersite from February 25, 2003 to December 31, 2006. The collected aerosol sample is illuminated with light from two light emitting diodes at wavelengths of 370 and 880 nm. Aerosol samples are collected for five minute periods. The air sample is collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 m or less. The concentration of black carbon corresponds to the 880 nm measurement. The black carbon equivalent at the ultraviolet wavelength was also determined. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Organic and Elemental Carbon Data
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NARSTO_EPA_SS_FRESNO_PM25_OC_EC is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Organic and Elemental Carbon Data. This data set contains measurements taken from a continuous carbon monitor, Model Rupprecht and Patashnick (R&P) 5400C operated from January 13, 2000 to March 31, 2005, and a Sunset Carbon Analyzer at the Fresno supersite. The sample collection time was 1 hour; the sample analysis time was one hour. Data were output once an hour, two hours after the start of sample collection. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Organic and Elemental Carbon Data
공공데이터포털
NARSTO_EPA_SS_FRESNO_PM25_OC_EC is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Organic and Elemental Carbon Data. This data set contains measurements taken from a continuous carbon monitor, Model Rupprecht and Patashnick (R&P) 5400C operated from January 13, 2000 to March 31, 2005, and a Sunset Carbon Analyzer at the Fresno supersite. The sample collection time was 1 hour; the sample analysis time was one hour. Data were output once an hour, two hours after the start of sample collection. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Elemental Carbon in 2.5 um Aerosol Fraction Data
공공데이터포털
NARSTO_EPA_SS_FRESNO_EC_PM25_FRACTION is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Elemental Carbon in 2.5 um Aerosol Fraction Data product. This data set contains the measurements taken with a single and dual wavelength aethalometer. The single wavelength aethalometer (model AE14) was operated at the Fresno supersite from December 17, 1999 to September 27, 2002. This instrument used a broad spectrum incandescent lamp to illuminate the collected aerosol. Aerosol samples were collected for five minute periods. The air sample was collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 m or less. A single concentration of black carbon was determined for each five minute period. A dual-wavelength aethalometer (model AE21) operated at the Fresno supersite from February 25, 2003 to December 31, 2006. The collected aerosol sample is illuminated with light from two light emitting diodes at wavelengths of 370 and 880 nm. Aerosol samples are collected for five minute periods. The air sample is collected through a sharp cut size-selective cyclone to limit the size of particles to aerodynamic diameters of 2.5 m or less. The concentration of black carbon corresponds to the 880 nm measurement. The black carbon equivalent at the ultraviolet wavelength was also determined.The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Particulate Nitrate and Sulfate Data
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The NARSTO_EPA_SS_FRESNO_PM25_NO3_SO4 is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Particulate Matter (PM) 2.5 Particulate Nitrate and Sulfate Data. This data set contains measurements taken from two nitrate monitors and one sulfate monitor operated at the Fresno Supersite. The sample collection time for all instruments was 8 minutes. The sample analysis time was 2 minutes. Data were output once every 10 minutes. The Rupprecht and Patashnick (R&P) Ambient Particulate Nitrate Monitor measured the amount of particulate nitrate in an air sample at a nearly continuous rate. The Rupprecht and Patashnick (R&P) Ambient Particulate Sulfate Monitor measured the amount of particulate sulfate in an air sample at a nearly continuous rate. The ambient aerosol was collected by impaction on a small metallic strip. At the end of collection, the strip was heated to vaporize and decompose the particulate matter into oxides which were then measured. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Los Angeles Aethalometer Elemental Carbon Data
공공데이터포털
NARSTO_EPA_SS_LOS_ANGELES_AETHALOMETER_EC_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Los Angeles Aethalometer Elemental Carbon Data. Data was collected between September 2000 to October 2003 at Claremont, Downey, Riverside, Rubidoux, and the University of Southern California (USC) in Los Angeles County, California. The Magee Scientific AE-2 series dual beam aethalometer was used in a mobile trailer to collect mass concentrations of optically absorbing black carbon particles in the submicron size range during September 15, 2000 to October 16, 2003. The Aethalometer collected aerosol continuously on quartz fiber paper and determined the increment of optically absorbing black carbon per unit volume of sampled air every 5 minutes. The overall objective of the Los Angeles Supersite in Southern California Particle Center and Supersite (SCPCS) was to conduct monitoring and research that contributes to a better understanding of the measurement, sources, size distribution, chemical composition and physical state, spatial and temporal variability, and linkages to health effects of airborne particulate matter in the Los Angeles Basin (LAB ). The 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Fresno, Beta Attenuation Monitors (BAM), Particulate Mass Concentration Data
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NARSTO_EPA_SS_FRESNO_BAM_PM_MASS FRACTION is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Fresno, Beta Attenuation Monitors (BAM), Particulate Mass Concentration Data product. This data set contains measurements taken from two BAMs, PM10, and PM2.5, operated at the Fresno Supersite. The MetOne BAM Monitor measured the attenuation of a beam of beta particles (electrons) generated by a 14ºC source transmitted through an aerosol sample collected on a glass fiber filter tape. Before sample collection, the beta attenuation was measured through a clean part of the tape to obtain a baseline. A sample was collected on the same location on the tape. After sample collection, the beta attenuation was measured through the exposed part of the tape. The net attenuation is proportional to the amount of mass collected on the filter. A mass flow controller controls the flow rate during sample collection at a flow rate of approximately 16.7 l/min. The mass concentration of the collected aerosol was determined from the net attenuation, the sample air flow, the sample time, and the attenuation coefficient for the instrument. The Fresno Supersite is one of several Supersites established in urban areas within the United States by the EPA to better understand the measurement, sources, and health effects of suspended particulate matter (PM). The site is located at 3425 First Street, approximately 1 km north of the downtown commercial district. First Street was a four-lane artery with moderate traffic levels. Commercial establishments, office buildings, churches, and schools were located north and south of the monitor. Medium-density single-family homes and some apartments were located in the blocks to the east and west of First Street. The Fresno Supersite began operation in May of 1999.The 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 the following 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Los Angeles Tapered-Element Oscillating Microbalance (TEOM) Particulate Matter (PM) 2.5 Mass Concentration Data
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NARSTO_EPA_SS_LOS_ANGELES_TEOM_PM25_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Los Angeles Tapered-Element Oscillating Microbalance (TEOM) Particulate Matter (PM) 2.5 Mass Concentration Data. It was collected between December 2000 and September 2002 using a Tapered-Element Oscillating Microbalance (TEOM). At Downey and Riverside (Los Angeles County, California), the standard TEOM Model 1400a was used in a mobile trailer to collect PM2.5 mass concentration data every 30 minutes during December 19, 2000 to May 22, 2001. At Claremont and Rubidoux (Los Angeles County, California), Differential TEOM (proto-type) was used in a mobile trailer to collect hourly PM2.5 mass concentration data during August 17, 2001 to September 3, 2002. The overall objective of the Los Angeles Super Site in Southern California Particle Center and Supersite (SCPCS) is to conduct monitoring and research that contributes to a better understanding of the measurement, sources, size distribution, chemical composition and physical state, spatial and temporal variability, and linkages to health effects of airborne particulate matter in the Los Angeles Basin.The U.S. EPA Particulate Matter (PM) Super Sites 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.
NARSTO EPA Supersite (SS) Los Angeles Harvard/EPA Annular Denuder System (HEADS) Data
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NARSTO_EPA_SS_LOS_ANGELES_HEADS_PART_IONS_MASS is the North American Research Strategy for Tropospheric Ozone (NARSTO) Environmental Protection Agency (EPA) Supersite (SS) Los Angeles Harvard/EPA Annular Denuder System (HEADS) Data product. This product was collected between December 2001 and June 2003. The HEADS model URG-2000-30DI was used to collect the Particulate Matter (PM) 2.5 mass concentration data episodically from December 6, 2001 - August 21, 2002. It was also used to collect sulfate and nitrate ions at Claremont from September 28, 2001 - August 6, 2002, at Riverside from March 14 - June 6 2001, and the University of Southern California from October 8, 2002 - June 11, 2003. HEADS uses chemically coated annular denuder tubes to selectively remove gaseous pollutants before PM. The overall objective of the Los Angeles Supersite in Southern California Particle Center and Supersite (SCPCS) was to conduct monitoring and research that contributes to a better understanding of the measurement, sources, size distribution, chemical composition and physical state, spatial and temporal variability, and linkages to health effects of airborne particulate matter in the Los Angeles Basin (LAB). The 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 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, which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was 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 still available.