Collaborative Research: Measurements of Gaseous Nitric Acid, Nitrogen Dioxide, and Atmospheric Nitrogen Deposition Fluxes in Two Mixed-Hardwood Forests

Aerodyne Research Inc, Billerica MA

Investigators

Abstract

Reactive nitrogen species play an important role in tropospheric photochemistry, controlling ozone formation, affecting the concentration of hydroxyl radicals, and contributing to deposition of acids and nutrients. Forested areas in the United States present a major sink for reactive nitrogen through dry deposition, attributed mainly to nitric acid. This project utilizes a newly developed a newly developed dual tunable diode laser absorption spectrometer to make eddy correlation flux measurement of nitrogen dioxide and nitric acid deposition at Harvard Forest. The goal is to test ideas about mechanisms controlling partitioning among of nitrogen oxide species and their ultimate removal from the atmosphere. The observations will produce new information on seasonal and interannual variability in the reactive nitrogen budget, and quantify an important component of acid deposition to forest ecosystems. This research is a collaborative effort with Steven Wofsy, Harvard University.