On the Role of Organic Nitrates, RONO2, in the NOx Budget: Constraints from Measurements During SOAS

Abstract:

In rural and forested areas, the formation of alkyl nitrates (RONO₂) has recently been shown to be the most important sink of NO_x (Browne et al. 2013). However, the lifetime and fate of RONO₂ are still poorly understood, especially for biogenic, multifunctional nitrates. We use measurements of NO_x, RONO₂, HNO₃, HO_x, and VOCs obtained during summer 2013 in rural Alabama as part of the Southern Oxidant and Aerosol Study (SOAS) to provide new constraints on the production and loss of biogenic RONO₂ and thus to understand their role in setting the NO_x lifetime. We find that the RONO₂ in the region are short-lived, with a lifetime of approximately 2 hours. Processes affecting this lifetime and consequences for NO_x will be described.