Modeling county-level benzene emissions using transportation analysis zones in the Denver metro area

The link between exposure to benzene (an important toxic air pollutant) and physical health is well-documented as benzene is a known carcinogen. Understanding benzene concentration distributions in urban areas is very important and can be done using air dispersion models. An essential input requirement for dispersion models is the spatial and temporal allocation of emissions. Since most county-level benzene emissions come from gasoline powered motor vehicles, the goal of this work was to develop a new method of county-level benzene emission allocation using transportation analysis zones (TAZs) commonly used in travel demand models. The high spatial resolution provided by the TAZ allocation method helped visualize different flux patterns generated from five emission sectors and identified where more effort is needed to reduce benzene concentrations. The new allocation method was also tested using the AERMOD dispersion model to estimate benzene concentrations in the Denver metropolitan area. The model performance was assessed using 2014 morning benzene measurements from a monitoring station located in downtown Denver; results showed an acceptable model-to-monitor ratio. The model was also used to investigate the effect of temperature inversions on morning benzene concentrations. As expected, predicted benzene concentrations were higher during temperature inversions and model-to-monitor ratios during investigated days were within a factor of two. The TAZ allocation modeling methodology demonstrated in this work can improve the estimation of air pollution exposure in future health-related studies. &nbsp;</p

The Finer Things in Life: Comparing High Resolution Fossil Fuel Carbon Dioxide Emissions Inventories

The quantification of fossil fuel contributions to carbon dioxide concentrations is necessary for monitoring, reporting, and verifying carbon dioxide emissions, which is necessary for the success of international agreements to reduce emissions. However, existing fossil fuel carbon dioxide (FFCO2) emissions inventories vary in terms of the data and methods used to estimate and distribute FFCO2. This paper compares how the approaches used to create FFCO2 emissions inventories effect the magnitude and spatial distribution of emissions estimates. Five FFCO2 emission inventories were compared: Carbon Dioxide Information and Analysis Center (CDIAC), Emission Database for Global Atmospheric Research (EDGAR), Fossil Fuel Data Assimilation System (FFDAS), Open-source Data Inventory for Anthropogenic CO2 (ODIAC), and Vulcan. The effects of using specific approaches in the creation of spatially explicit FFCO2 emissions inventories, and the effect of resolution on data representation are analyzed using graphical, numerical, and cartographic data. Results are analyzed to understand the effects of using top-down versus bottom-up approaches, nightlights versus population, and the inclusion of large point sources. Understanding the relationship between these patterns and how they change with resolution supports future development of gridded FFCO2 emissions inventories

Industrial Toxic Air Pollutants In Colorado Communities: Investigating Source and Health Impact of Odors and Benzene

Exposure to industrial odors and toxic air pollutants are major public health concerns in urban areas. It is difficult to link industrial odors to physical health due to their low toxicity thresholds. However, industrial odors do have serious impact on mental health. In 2014, North Denver communities identified industrial odor pollution as a top priority. The first goal of this work was to investigate the impact of industrial odors on residents&rsquo; subjective well-being in North Denver and similar communities. A novel approach was used to evaluate subjective well-being based on three aspects. Odors were evaluated using perceived odor and odor acceptability. The data were collected using an online survey. Based on the analysis, the participants who reported that air was very fresh or the odor was highly acceptable, also reported higher levels of well-being. North Denver and Greeley were the most affected communities by odors. The second goal was to test the feasibility of a new method that identifies odor sources by linking wind direction and odor data from social participation. For more than one year, residents reported time, date, location and description of the odor occurrence using smartphone technology. Using the date and time of the odor report submission, wind data were collected from local air monitoring stations. The method has proven its applicability and important odor sources in North Denver and Greeley were identified. Unlike industrial odors, the link between exposure to benzene (an important toxic air pollutant) and physical health is well-documented. Benzene is a known carcinogenic. Understanding benzene concentration distribution is important which can be done by dispersion air quality models. An essential input requirement for dispersion models is the spatial allocation of emissions. The final goal of this work was to develop a new method of county-level benzene emission allocation using transportation analysis zones (TAZs). The resolution provided by the TAZ allocation method helped visualizing different flux patterns generated from five emission sectors. The new method identified key emission areas where more effort is needed to reduce benzene concentrations. The new allocation method was also tested using an AERMOD model to estimate morning benzene concentrations in Denver area. The model preliminary results showed an acceptable model-to-monitor ratio. The model was also used to investigate the impact of temperature inversions on morning benzene concentrations. Benzene predicted concentrations were higher during temperature inversions and model-to-monitor ratios during investigated days were within a factor of two. However, the model results presented in this study should be interpreted with caution because the meteorological data were obtained from a station that was located far from Denver urban area.</p

A GIS-Based Approach to Spatial Allocation of Area Source Solvent Emissions

Current area source emission inventories estimate total emissions for various industrial, commercial, and consumer activities at the county or higher levels. The lack of emission estimates at subcounty levels severely limits the modeling and planning capabilities in urban and regional air quality management. This paper extends current area source emission inventory methodology by developing a geographical information system (GIS) based approach for allocating county-level emission estimates to subcounty units. The new methodology uses GIS to develop and integrate spatial data, to analyze spatial variations in emissions, and to derive input to cell-based air pollution models. This approach incorporates statistical models to predict the spatial distribution of emission source activities based on widely available data. The paper presents an application of the proposed approach to emission inventory of the adhesives and sealants category in the Sacramento modeling region

Estimación, análisis y evaluación de inventarios de emisiones atmosféricas antropogénicas a escala local, regional y continental

En este trabajo se aborda la elaboración de inventarios de emisiones atmosféricas mediante la combinación de diferentes metodologías, su análisis y evaluación para su posterior aplicación en tres escalas espaciales: continental, regional y local. Se han empleado distintas técnicas, pero manteniendo la coherencia entre los inventarios desarrollados en las distintas escalas