Role of the dew water on the ground surface in HONO distribution: a case measurement in Melpitz - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Atmospheric Chemistry and Physics Année : 2020

Role of the dew water on the ground surface in HONO distribution: a case measurement in Melpitz

Résumé

To characterize the role of dew water for the ground surface HONO distribution, nitrous acid (HONO) measurements with a Monitor for AeRosols and Gases in ambient Air (MARGA) and a LOng Path Absorption Photometer (LOPAP) instrument were performed at the Leibniz Institute for Tropospheric Research (TROPOS) research site in Melpitz, Germany, from 19 to 29 April 2018. The dew water was also collected and analyzed from 8 to 14 May 2019 using a glass sampler. The high time resolution of HONO measurements showed characteristic diurnal variations that revealed that (i) vehicle emissions are a minor source of HONO at Melpitz station; (ii) the heterogeneous conversion of NO2 to HONO on the ground surface dominates HONO production at night; (iii) there is significant nighttime loss of HONO with a sink strength of 0:16 +/- 0:12 ppbv h(-1); and (iv) dew water with mean NO2- of 7:91 +/- 2:14 mu gm(-2) could serve as a temporary HONO source in the morning when the dew droplets evaporate. The nocturnal observations of HONO and NO2 allowed the direct evaluation of the ground uptake coefficients for these species at night: gamma NO2 -> HONO = 2:4 x 10(-7) to 3.5 x 10(-6), gamma(HONO,ground) D 1.7 x 10(-5) to 2.8 x 10(-4). A chemical model demonstrated that HONO deposition to the ground surface at night was 90 %-100% of the calculated unknown HONO source in the morning. These results suggest that dew water on the ground surface was controlling the temporal HONO distribution rather than straightforward NO2-HONO conversion. This can strongly enhance the OH reactivity throughout the morning time or in other planted ar- eas that provide a large amount of ground surface based on the OH production rate calculation.
Fichier principal
Vignette du fichier
acp-20-13069-2020.pdf (599.63 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03024762 , version 1 (21-01-2021)

Licence

Paternité - Pas d'utilisation commerciale

Identifiants

Citer

Yangang Ren, Bastian Stieger, Gerald Spindler, Benoit Grosselin, Abdelwahid S Mellouki, et al.. Role of the dew water on the ground surface in HONO distribution: a case measurement in Melpitz. Atmospheric Chemistry and Physics, 2020, 20 (21), pp.13069-13089. ⟨10.5194/acp-20-13069-2020⟩. ⟨hal-03024762⟩
83 Consultations
137 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More