Scanning electron microscope analysis of dust in rat lung tissues.

SCAR_A_ER2_MAS data are Sulfates, Clouds and Radiation America (SCARA) NASA ER2 Moderate Resolution Imaging Spectrometer (MODIS) Airborne Simulator (MAS) Data in Hierarchical Data Format (HDF).Smoke/Sulfates, Clouds and Radiation - America (SCAR-A) data include physical and chemical components of the Earth's surface, the atmosphere and the radiation field collected in the eastern part of the United States with an emphasis in air pollution.The primary objective of the SCAR-A experiment was to help scientists characterize the the relationship between sulfate particles and clouds' reflective properties. Sulfate aerosols are believed to provide condensation nuclei, resulting in smaller, more numerous droplets within a cloud. SCAR-A was the first in a series of experiments. It was was followed by the SCAR-C experiment conducted over California in 1994. A third experiment, SCAR-B was conducted in Brazil during August and September 1995. The MODIS Airbourne Simulator (MAS) is a modified Daedalus Wildfire scanning spectrometer which flies on a NASA ER-2 and provides spectral information similar to that provided by the Moderate Resolution Imaging Spectroradiometer (MODIS), launched on Terra (EOS AM-1) in 1999 and Aqua (EOS PM-1) in 2002. The MAS spectrometer acquires high spatial resolution imagery in the wavelength range of 0.55 to 14.3 microns. A total of 50 spectral bands are available in this range, and the digitizer can be configured to collect data from any 12 of these bands. The digitizer was configured with four 10-bit channels and seven 8-bit channels. The MAS spectrometer was mated to a scanner subassembly which collected image data with an IFOV of 2.5 mrad, giving a ground resolution of 50 meters from 20000 meters altitude, and a cross track scan width of 85.92 degrees. The data granules were written using the self documenting file storage format provided through the netCDF interface routines included in the HDF libraries.

NARSTO_PAC2001_CASSIAR_TUNNEL_GAS_PM_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Pacific 2001 Air Quality Study (PAC2001) Cassiar Tunnel Gaseous and Particle Mass and Composition Data product. This data product was obtained from August 8-15, 2001 during the PAC2001.The Cassiar Tunnel site is located at 49 17' 01.9 N and 123 01' 54.2 W, at 40 m above sea level (a.s.l.). The tunnel is used mostly by light duty traffic with peak traffic volumes at rush hours. The goal of measurements at this site was to reduce the uncertainty in mobile source inventory for gas and particle emissions from light duty traffic sources, emphasizing the emissions of the precursors to Particulate Matter (PM) formation and primary PM emissions for comparison with tailpipe emissions data from traditional testing conducted in laboratory on mobile source emissions, particularly for mass emission rates and chemical profiles. For several measurements, different sampling and analytical techniques were used as a check on the accuracy of the measurements. For most gas measurements, two sets of instruments were deployed, one at each end of the tunnel, whereas most of the PM measurements were conducted at the exit end of the tunnel. Gas measurements included the typical pollution gases (SF6 as the tracer, NOx, N2O, CO, CO2, methane, SO2, VOCs, carbonyls, organic acids, NH3, Graham and Gray, 2002). The PM chemical and physical properties were measured in great details. For physical properties, particle number size distributions from 10 nm to 3 um were measured, and hygroscopic properties were measured at two sizes (Prenni et al., 2002). Chemical measurements characterized the mass, inorganic and carbonaceous compositions of the primary particles. The PAC2001 was conducted from August 1 until September 31, 2001 in the Lower Fraser Valley (LFV), British Columbia, Canada. The study consisted of individual research projects organized to address several issues on ambient particulate matter and ozone that are important to policy makers. A special issue of Atmospheric Environment [Vol. 38(34), Nov 2004] described specific study objectives (Li, 2004) and presented a series of results papers from the field study. The ground sampling sites during the study were (1) Cassiar Tunnel, (2) Slocan Park, (3) Langley Ecole Lochiel, (4) Sumas Eagle Ridge, and (5) Golden Ears Provincial Park. Aloft measurements were taken from a Convair 580 and a Cessna 188. Selected measurement data were compiled for each site and aircraft and are archived as site-specific data sets.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.

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.

NARSTO_Texas_PM2.5_Sampling_and_Analysis_Study_1997-1998_ is the North American Research Strategy for Tropospheric Ozone (NARSTO) Texas Particulate Matter (PM) 2.5 Sampling and Analysis Study: 1997-1998 Data. The data for this product was collected from March 11, 1997 to March 12, 1998. The City of Houston, the Texas Natural Resource Conservation Commission (TNRCC), and the Houston Regional Monitoring Network sponsored sampling and analysis of PM2.5 samples taken over the course of one year, from March 11, 1997 to March 12, 1998. Objectives of the study were to determine the levels and chemical composition of PM2.5 in Houston and other cities in Texas and to determine the background levels and chemical composition of PM2.5 transported into Houston. During the sampling effort, 24-hour PM2.5 mass measurements were acquired from 15 sites throughout the state of Texas, using DRI's MEDVOL particle samples. All of the Teflon filters were analyzed for mass by gravimetry and a selected subset of the Teflon and quartz fiber filters were subjected to full chemical analysis. These measurements were taken in anticipation of the U.S. EPA revising PM2.5 and PM10 NAAQS. These results could be used to establish background PM conditions and determine compliance with new PM standards. Various sampler configurations allow evaluation of data precision, accuracy, and validity. 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.

The Earth Surface Mineral Dust Source Investigation (EMIT) instrument measures surface mineralogy, targeting the Earth’s arid dust source regions. EMIT is installed on the International Space Station (ISS) and uses imaging spectroscopy to take measurements of the sunlit regions of interest between 52° N latitude and 52° S latitude. An interactive map showing the locations of methane plumes along with metadata, regions being investigated, current and forecasted data coverage, and additional data resources can be found on the VSWIR Imaging Spectroscopy Interface for Open Science (VISIONS) [EMIT Open Data Portal](https://earth.jpl.nasa.gov/emit/data/data-portal/coverage-and-forecasts/).In addition to its primary objective described above, EMIT has demonstrated the capacity to characterize methane (CH4) and carbon dioxide (CO2) point-source emissions by measuring gas absorption features in the short-wave infrared bands. The EMIT Level 2B Greenhouse Gas (GHG) series of products can be used to identify and quantify point source emissions. The EMIT Level 2B Estimated Methane Plume Complexes (EMITL2BCH4PLM) Version 1 data product provides estimated methane plume complexes in parts per million meter (ppm m) along with uncertainty data. The EMITL2BCH4PLM data product will only be generated where methane plume complexes have been identified. To reduce the risk of false positives, all [EMITL2BCH4ENH](https://doi.org/10.5067/EMIT/EMITL2BCH4ENH.001) data undergo a manual review (or identification and confirmation) process before being designated as a plume complex. For more information on the manual review process, see Section 4.2.2 of the EMIT GHG Algorithm Theoretical Basis Document (ATBD). Each EMITL2BCH4PLM granule is sized to a specific plume complex but may cross multiple EMITL2BCH4ENH granules. A list of source EMITL2BCH4ENH granules is included in the GeoTIFF file metadata as well as the GeoJSON file. Each EMITL2BCH4PLM granule contains two files: one Cloud Optimized GeoTIFF (COG) file at a spatial resolution of 60 meters (m) and one GeoJSON file. The EMITL2BCH4PLM COG file contains a raster image of a methane plume complex extracted from EMITL2BCH4ENH v001 data. The EMITL2BCH4PLM GeoJSON file contains a vector outline of the plume complex, a list of source scenes, coordinates of the maximum enhancement values, and the uncertainty of the plume complex.Known Issues* Data acquisition gap: From September 13, 2022, through January 6, 2023, a power issue outside of EMIT caused a pause in operations. Due to this shutdown, no data were acquired during that timeframe.

NARSTO_PAC2001_GOLDEN_EARS_GAS_PM_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Pacific 2001 Air Quality Study (PAC2001) Golden Ears Gaseous, Particulate Matter (PM), and Meteorological Data product. Data was obtained from August 3-11, 2001 during PAC2001. The Golden Ears Provincial Park (GEP) site was situated at 49.27783 N, 120.51544 W, and 220 m above sea level (a.s.l.), about 45 km east of Vancouver in the Coastal Mountains. The sampling site, located at the park ranger headquarters compound, was in a small forest clearing of about 65 x 130 m and was surrounded by tall coniferous trees (dominated by Western Hemlock, Western Red Cedar, and Douglas Fir, typically seen in the Coastal Mountains) with canopy heights about 10-15 m near the site but rising to over 30 m in the park in general. The temporary labs were about 10 m away from the closest trees. The closest urban area, Maple Ridge, is about 8 km to the south. Different from the other sites, the Golden Ears Provincial Park site was dedicated to the question of secondary biogenic particles production from forestry precursors. The 1995 emission inventories for the LFV indicate strong monoterpene emissions from forests in the Coastal Mountains and the Cascade Ranges. A previous study here showed significant ambient concentrations of terpenes. Monoterpenes are converted into particles in the gas phase with high yields. While the forests were known to release monoterpenes, the magnitude of the contribution to fine particles in the LFV was not clear. Measurements at the GEP site were designed to provide information on secondary biogenic particle production from forestry precursors, such as monoterpenes. PAC2001 was conducted from August 1 to September 31, 2001 in the Lower Fraser Valley (LFV), British Columbia, Canada. The study consisted of individual research projects organized to address several issues on ambient PM and ozone that are important to policy makers. A special issue of Atmospheric Environment [Vol. 38(34), Nov 2004] described specific study objectives (Li, 2004) and presented a series of results papers from the field study. There were 5 ground sampling sites during the study, which included: Cassiar Tunnel, Slocan Park, Langley Ecole Lochiel, Sumas Eagle Ridge, and Golden Ears Provincial Park. Aloft measurements were taken from a Convair 580 and a Cessna 188. Selected measurement data were compiled for each site and aircraft and are archived as site-specific data sets.North American Research Strategy for Tropospheric Ozone (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_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