edu.ucar.opensky::articles:13135 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T03:40:08.639867 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7kd1zt8 Understanding the role of the ground surface in HONO vertical structure: High resolution vertical profiles during NACHTT-11 2013-09-16T00:00:00Z publication https://n2t.org/ark:/85065/d7kd1zt8 https://doi.org/10.1002/jgrd.50721 VandenBoer, T. author Brown, S. author Murphy, J. author Keene, W. author Young, C. author Pszenny, A. author Kim, Saewung author Warneke, C. author De Gouw, J. author Maben, J. author Wagner, N. author Riedel, T. author Thornton, J. author Wolfe, D. author Dubé, W. author Öztürk, F. author Brock, C. author Grossberg, N. author Lefer, B. author Lerner, B. author Middlebrook, A. author Roberts, J. author UCAR/NCAR - Library publisher A negative-ion proton-transfer chemical ionization mass spectrometer was deployed on a mobile tower-mounted platform during Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT) to measure nitrous acid (HONO) in the winter of 2011. High resolution vertical profiles revealed (i) HONO gradients in nocturnal boundary layers, (ii) ground surface dominates HONO production by heterogeneous uptake of NO₂, (iii) significant quantities of HONO may be deposited to the ground surface at night, (iv) daytime gradients indicative of ground HONO production or emission, and (v) an estimated surface HONO reservoir comparable or larger than integrated daytime HONO surface production. Nocturnal integrated column observations of HONO and NO₂ allowed direct evaluation of nocturnal ground surface uptake coefficients for these species (ώNO₂, surf = 2  x 10⁻⁶ to 1.6 × 10⁻⁵ and γHONO, surf = 2 × 10⁻⁵ to 2 × 10⁻⁴). A chemical model showed that the unknown source of HONO was highest in the morning, 4 × 106 molecules cm⁻³ s⁻¹ (600 pptv h⁻¹), declined throughout the day, and minimized near 1 × 106 molecules cm⁻³ s⁻¹ (165 pptv h⁻¹). The quantity of surface-deposited HONO was also modeled, showing that HONO deposited to the surface at night was at least 25%, and likely in excess of 100%, of the calculated unknown daytime HONO source. These results suggest that if nocturnally deposited HONO forms a conservative surface reservoir, which can be released the following day, a significant fraction of the daytime HONO source can be explained for the NACHTT observations. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2013 American Geophysical Union. None eng geoscientificInformation