Constraining the Chemistry of Particle Formation and Growth in the Southern Great Plains

Constraining the Chemistry of Particle Formation and Growth in the Southern Great Plains

Eleanor Browne, University of Colorado Boulder (Principle Investigator)
Manjula Canagaratna, Aerodyne Research Inc. (co-Principle Investigator)
Jordan Krechmer, Aerodyne Research Inc. (co-Investigator)
Harald Stark, Aerodyne Research Inc. (co-Investigator)
Douglas Worsnop, Aerodyne Research Inc. (co-Investigator)
Currently, the ability of particles to influence cloud formation and affect radiative forcing is the largest uncertainty in our understanding of the global energy balance. Since the majority of particles originate from nucleation and growth of gas-phase precursors, understanding these processes is critical in order to develop an accurate understanding of the Earth’s energy balance. While recent developments in analytical instruments have greatly increased our knowledge of the processes controlling the initial formation of particles and have demonstrated that compounds such as amines and oxidized organic molecules play an important role in driving formation and subsequent growth, there still exists substantial uncertainty in the exact processes.
This work proposes to advance the understanding of aerosol

aerosols

Small particles or droplets, such as wildfire smoke, volcanic gases, or salty sea spray, that float in the air. They are emitted by both natural events and human activities.

Source: NASA Global Climate Change Source

formation and growth through measurements of the gas-phase species affecting new particle formation and growth at the Department of Energy Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) research facility. Specifically, this work will (1) analyze previous measurements of ambient anions, (2) identify and quantify new gas-phase bases (ammonia, amines, urea), oxygenated organics, and ambient ions at SGP in two different seasons (3) investigate the connection between gaseous composition and rates of particle formation and growth, (4) investigate if novel nitrogen

nitrogen

Classified as a nonmetal, nitrogen is a gas at room temperature. Nitrogen dilutes oxygen and prevents rapid burning at the Earth's surface, and accounts for ~78 percent of Earth's atmosphere.

Source: National Library of Medicine Source

compounds (e.g., urea, diamines) contribute to particle formation, and (5) investigate the processes controlling the abundance of gas-phase bases.
Co-located measurements by chemical ionization mass spectrometry

mass spectrometry (MS)

Mass spectrometry (MS) is an analytical technique that separates ionized particles such as atoms, molecules, and clusters and can be used to determine the molecular weight of the particles.

Source: National Library of Medicine Source

and atmospheric pressure interface mass spectrometry have been transforming our understanding of particle formation and growth over the past several years. However, these measurements have been performed in only a few ecosystems.

ecosystem

A natural community of plants, animals, and other living organisms and the physical environment in which they live and interact.

Source: A student's guide to Global Climate Change Source

With its combined influences of biogenic and anthropogenic sources, the Southern Great Plains ARM site is ideal for using these techniques to test our understanding of the processes controlling particle formation and growth. The work proposed here will improve the understanding of how different chemical processes affect particle growth at the Southern Great Plains ARM site. Additionally, it will add some of the first high-resolution measurements of ambient ion composition in North America to a growing collection of global measurements. Ultimately, the insights gained from the proposed work will result in an improved understanding of particle formation and growth and, consequently, global energy budget.