NOAA’s climate program office announced funding for research that improves our understanding of emissions – and the chemical transformation of those emissions – in the urban atmosphere. Four of the 10 new projects went to researchers at Colorado State University, totaling more than $ 2.2 million at CSU.
The federal research program, called Atmospheric Chemistry, Carbon Cycle, and Climate, competed for projects totaling $ 5.48 million in grants.
Urban air quality
Despite decades of declining ground-level ozone and fine particulate matter, many metropolitan areas across the United States continue to violate the eight-hour ozone standard under the Clean Air Act. This could be the result of unforeseen trends in emissions, the growing influence of regional background sources, long-range transport of emissions, changes in atmospheric chemistry and / or a consequence of climate change with increasingly frequent, longer and more intense heat waves in the United States. In fact, global warming and increasing episodes of extreme heat – because they worsen air quality – require higher emission reductions to meet air quality standards.
Recent research has also revealed significant gaps in the understanding of urban chemistry. In urban atmospheres, volatile chemicals such as coatings, adhesives, inks, personal care products and cleaning agents appear as major sources of volatile organic compounds that have harmful effects on the environment and health .
The emissions and impacts of volatile chemicals on atmospheric chemistry are not well understood. In the presence of nitrogen oxides, volatile organic compounds undergo a chemistry that leads to the formation of ground-level ozone and aerosols. In a pilot study, field measurements in New York found that scented consumer products, such as air fresheners, and other volatile chemicals accounted for more than half of anthropogenic VOC emissions and increased the formation of ground-level ozone during a heat wave. Ground-level ozone can trigger various health problems in children, the elderly and people of all ages who suffer from lung diseases such as asthma.
To improve understanding of the emissions and chemical reactions that affect urban air quality and climate, the NOAA Chemical Sciences Laboratory is planning the aircraft-based field campaign on observed atmospheric emissions and reactions of airplanes. mega-cities to marine areas (AEROMMA) to collect new observations from mega-cities to marine areas. environments, currently scheduled for summer 2023. CSU researchers will support and participate in the AEROMMA aircraft campaign in a variety of ways.
Here are the projects funded by CSU:
Near real-time aerosol composition measurements during emissions and atmospheric reactions observed from mega-cities to marine areas
Leader: Amy Sullivan, Research Scientist, Department of Atmospheric Sciences
Collaborator: Rodney Weber, Georgia Institute of Technology
This project will perform liquid particle sampler measurements on the AEROMMA WP-3 NOAA aircraft to provide aerosol composition data for the AEROMMA campaign. The proposed measurement protocol includes a well-established aerosol collection device which provides a liquid sample containing dissolved aerosol particles which can be analyzed by various methods. These measurements will provide high chemical specificity of the sulfur species to complement other measurements of the composition of the aerosols to be deployed, such as aerosol mass spectrometry, and will be used to answer the following research questions: What are the differences in type sulphate observed in urban areas vs. marine emissions? How important is the combustion of biomass in the study region during the summer? How does it compare to winter? What is the pH of the aerosol in the study area in summer? How does it compare to winter? Overall, the project will provide information that could guide emission control strategies and meet air quality standards to protect human health.
Ammonia for AEROMMA
Leader: Ilana Pollack, Research Scientist, Department of Atmospheric Sciences
Collaborators: Associate Professor Emily Fischer, Professor Jeffrey Pierce, Department of Atmospheric Sciences
Coastal mega-cities like Los Angeles and New York City experience some of the worst air qualities in the United States. The AEROMMA summer 2021 field campaign will focus on precursor emissions, pollutant formation and transport between mega-cities and marine environments. Ammonia in the gas phase will be an essential observation during the AEROMMA study. Ammonia is an unregulated air pollutant that contributes to the formation of fine particles and the deposition of nitrogen. However, our observations of atmospheric sources, sinks, and phase distribution of ammonia are limited compared to other major anthropogenic pollutants. Unlike the decrease in nitrogen oxide emissions from combustion sources, ammonia emissions from combustion and agricultural activities have increased and reduced nitrogen deposition has increased. Ammonia emissions, especially from vehicular sources in urban areas, are not well understood. This project will deploy a flight-ready quantum cascade tunable infrared laser direct absorption spectrometer aboard the NOAA WP-3 aircraft to provide gas phase ammonia observations for the AEROMMA field campaign. Ammonia measurement and analysis targets will provide information on the abundances and emissions of ammonia relative to other regulated pollutants as well as the chemical processes leading to the formation of fine particles in megacities and cities. marine environments. This information will help guide emission control strategies and policies.
Understand the emerging contribution of volatile chemicals and food cooking to air quality, aerosol size distribution, and climate-related properties at urban and regional scales
Responsible: Shantanu Jathar, Department of Mechanical Engineering
Collaborator: Jeffrey Pierce, Department of Atmospheric Sciences
Learn more about this project, as well as Jathar’s funding from the NSF.
While emissions from traditional sources have been tightly controlled, the newly identified sources, namely volatile chemicals and cooking of food, can contribute significantly to the chemistry and composition of the atmosphere as well as to the quality of the atmosphere. air on an urban and regional scale. The objective of this study is to understand the emerging role of volatile chemicals and food cooking emissions on ozone and organic aerosols, as well as the size distribution of aerosols in the urban atmosphere, in the evolution of the leeward plume and the regional properties of aerosols. The project has three objectives. In Objective 1, recent laboratory data will be exploited to develop mechanisms and parameterizations to represent the formation of ozone and aerosols from volatile chemicals and cooking sources. In Objective 2, aircraft observations and plume model simulations will be used to understand the formation and evolution of the mass, size and composition of ozone and aerosols in urban plumes. , sampled during the AEROMMA field campaign. In objective 3, the mechanisms and parameters developed and evaluated in the previous objectives will be used in a regional chemistry-climate model to simulate atmospheric chemistry and air quality in New York and four other North American cities studied during of the AEROMMA field campaign. The plume model and climate model simulations will quantify the contribution of volatile chemicals and cooking sources to urban and regional load, ozone and aerosols and test whether inclusion of these sources improves model performance. in these cities.
Reactive organic gas flows in New York: direct quantification by multi-instrument eddy covariance in support of AEROMMA
Responsible: Delphine Farmer, Department of chemistry
Contributors: Dylan Millet and Timothy Griffis, University of Minnesota
Urban emissions of volatile organic compounds contribute to smog through the formation of ozone and secondary organic aerosols. Quantifying urban sources of volatile organic compounds is a major issue of importance for air quality and for understanding the reactive carbon cycle. This project will help solve this problem by directly quantifying the urban flux of reactive carbon using a measure of atmospheric turbulence called turbulent covariance.
Specifically, the project applies two complementary time-of-flight chemical ionization mass spectrometers to measure the fluxes, gradients and concentrations of a wide range of reactive volatile organic compounds from a tower in the metropolitan area of New York as part of AEROMMA. The measurements will make a key contribution to the larger AEROMMA campaign by sampling a predominantly residential footprint that represents an essential part of New York’s diverse landscape. The project provides significant broader impacts to the scientific community and the general public through: a better understanding of volatile organic compounds to improve atmospheric models; better distribution of sources for more accurate forecasts of air quality; and unique opportunities for public engagement around the science of air pollution.
What scientific objectives do the grants support?
In FY2021, the Atmospheric Chemistry, Carbon Cycle and Climate program focused on a subset of AEROMMA by seeking to support studies on emissions and chemical transformation in the urban atmosphere. More specifically, the program supports types of projects that:
• Determine the emissions of organics and chemistry, including poorly studied volatile chemicals in order to better understand the impact on ozone and aerosol formation, and to study their relative importance on the quality of the air. urban air compared to other sources of volatile organic compounds such as energy-related cooking and natural sources.
• Determine reactive nitrogen emissions and chemistry in urban corridors to understand the current importance of combustion and non-combustion sources, continue trend analysis and determine changes in the chemistry of the nitrogen cycle. reagent and its influence on the formation of ozone and aerosols.
• Determine the fraction of urban emissions of volatile organic compounds and nitrogen oxides associated with carbon dioxide and methane emissions from transport, buildings, industry and landfills to quantify the corresponding benefits of management. urban air quality and carbon emissions.
• Investigate urban meteorology to better understand the impacts of extreme heat on urban air quality, urban heat islands and the role of long-distance transportation in relation to local sources of air pollution.