Long-term, continuous formaldehyde measurements in a rural Mid-Western location

Abstract:

The oxidation of volatile organic compounds (VOCs) leads to the formation of secondary pollutants, such as ozone and secondary organic aerosol. Formaldehyde, which has an atmospheric lifetime of a few hours, is a ubiquitous VOC oxidation product so is widely used as a tracer of local to regional VOC processing. Although formaldehyde measurements are widely used, there are few long-term, high-time resolution measurements available. During the spring of 2013 and summer and fall of 2014, the UW-Madison fiber laser induced fluorescence instrument monitored formaldehyde concentration at the Horicon Wildlife Refuge, which houses Wisconsin's National Core Monitoring and National Air Toxics Trends Station. We will present work that uses the formaldehyde measurements in conjunction with other data available at the Horicon site to evaluate different sources of anthropogenic influence on atmospherically rural areas. Particular attention will be paid to implications for SOA and ozone formation in this biogenically controlled area with regularly changing types and amounts of anthropogenic influence.