Long-range transported North American wildfire aerosols observed in marine boundary layer of eastern North Atlantic.

Wildfire is a major source of biomass burning aerosols, which greatly impact Earth climate. Tree species in North America (NA) boreal forests can support high-intensity crown fires, resulting in elevated injection height and longer lifetime (on the order of months) of the wildfire aerosols. Given the long lifetime, the properties of aged NA wildfire aerosols are required to understand and quantify their effects on radiation and climate.

Diesel Soot and Amine-Containing Organic Sulfate Aerosols in an Arctic Oil Field.

The rapid decrease in Arctic sea ice is motivating development and increasing oil and gas extraction activities. However, few observations of these local Arctic emissions exist, limiting the understanding of impacts on atmospheric composition and climate. To address this knowledge gap, the chemical composition of atmospheric aerosols was measured within the North Slope of Alaska oil fields during August and September 2016 using an aerosol time-of-flight mass spectrometer (ATOFMS) and a time-of-flight aerosol chemical speciation monitor (ToF-ACSM).

Isoprene photo-oxidation products quantify the effect of pollution on hydroxyl radicals over Amazonia.

Nitrogen oxides (NO ) emitted from human activities are believed to regulate the atmospheric oxidation capacity of the troposphere. However, observational evidence is limited for the low-to-median NO concentrations prevalent outside of polluted regions. Directly measuring oxidation capacity, represented primarily by hydroxyl radicals (OH), is challenging, and the span in NO concentrations at a single observation site is often not wide.

Isoprene photochemistry over the Amazon rainforest.

Isoprene photooxidation is a major driver of atmospheric chemistry over forested regions. Isoprene reacts with hydroxyl radicals (OH) and molecular oxygen to produce isoprene peroxy radicals (ISOPOO). These radicals can react with hydroperoxyl radicals (HO2) to dominantly produce hydroxyhydroperoxides (ISOPOOH).

Feasibility of a perfluorocarbon tracer based network to support monitoring, verification, and accounting of sequestered CO₂.

Carbon capture and sequestration (CCS) will act as a bridging technology necessary to facilitate a transition from fossil fuels to a sustainable energy based economy. The Department of Energy (DOE) target leak rate for sequestration reservoirs is 1% of total sequestered CO(2) over the lifetime of the reservoir. This is 0.

The atmospheric background of perfluorocarbon compounds used as tracers.

There are seven cyclic perfluoroalkane compounds, which can be detected in extremely low concentrations, that are used to track mass movement and transfer in a variety of research and practical applications. They are used in leak detection in underground storage and pipelines and in atmospheric transport and diffusion research on local, regional, and continental scales. They are likely to be a used globally for monitoring carbon sequestration in geological formations.