Abstract View
Lessons Learned from Deployment of a Novel Multiwavelength Photoacoustic Spectrometer to FIREX-AQ
BENJAMIN SUMLIN, Rajan K. Chakrabarty, Washington University in St. Louis
Abstract Number: 532
Working Group: Wildfire Aerosols
Abstract
The Multiwavelength Integrated Photoacoustic-Nephelometer (MIPN) is a field-portable, in situ, real-time, contact-free instrument designed for laboratory and field measurements of brown carbon (BrC) aerosol by targeting relevant wavelengths where BrC is known to absorb. A prototype MIPN (MIPN v1) was deployed to the FIREX-AQ field campaign where it measured light absorption by wildfire aerosols in the western United States in August 2019. As with many prototype instruments, the MIPN v1 had successes and failures during its first deployment which informed the next iteration of refinements, culminating in a modified MIPN v2.
During FIREX-AQ, The MIPN v1 measured light absorption by wildfire aerosols in parallel with a variety of instrumentation aboard the Aerodyne Mobile Laboratory. The month-long field campaign in this dynamic environment revealed several opportunities for improvement. Among the refinements are a modernized absorption sensor design, real-time self-diagnostics and internal monitoring, and a robust demodulation algorithm for recovering multiwavelength signals simultaneously. We present the motivation, design, construction, deployment, and refinement of the MIPN v2, focusing on specific upgrades made to the optoacoustic cavity and absorption sensors. Various quality-of-life upgrades to make the instrument more robust for field operation are also discussed within the context of results from the first deployment of the MIPN v1 to the field. A full characterization of the MIPN v2 will also be presented, and we will conclude with discussion on its use in future field campaigns.