Broad Band Cavity Enhanced Absorption Spectroscopy
Reactive gas phase species measurements
NO3 is the primary night-time atmospheric oxidant species and thus plays a crucial role in the chemistry of the atmosphere. It is especially important for oxidation of unsaturated VOCs, particularly those with multiple double bonds such as those from biogenic sources. As a result, NO3 measurements are critical for a full understanding of atmospheric oxidation processes.
The Broad Band Cavity Enhanced Absorption Spectroscopy instrument is the only one capable of measuring this compound. It also has the capability to measure N2O5, a reservoir species of NO3 and HONO, which is an important daytime source of the OH radical. This project sees the existing BBCEAS instrument upgraded to ensure the aircraft remains capable of measuring a range of reactive gas phase species, in particular NO3. It will ensure the instrument makes use of the latest developments in light sources, detection and pumping, future proofing it for the next 5-10 years.