Ground-based observation of lightning-induced nitrogen oxides at a mountaintop in free troposphere

Ryuichi Wada*, Y. Sadanaga, S. Kato, N. Katsumi, H. Okochi, Y. Iwamoto, K. Miura, H. Kobayashi, M. Kamogawa, J. Matsumoto, S. Yonemura, Y. Matsumi, M. Kajino, S. Hatakeyama

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


Lightning is an important source of nitrogen oxides (LNOx). The actual global production of LNOx is still largely uncertain. One of the reasons for this uncertainty is the limited available observation data. We measured the concentrations of total reactive nitrogen (NOy), nitric oxide (NO) and nitrogen dioxides (NO2) and then obtained NOx oxidation products (NOz: NOz = NOy - NOx) at a station at the top of Mount Fuji (3776 m a.s.l.) during the summer of 2017. Increases in NOy and NO2 were observed on 22 August 2017. These peaks were unaccompanied by increases in CO, which suggested that the observed air mass did not contain emissions from combustion. The backward trajectories of the above air mass indicated that it moved across areas where lightning occurred. The NOy concentration was also calculated by using a chemical transport model, which did not take NOx produced by lightning into account. Therefore, the NOy concentration due to lightning can be inferred by subtracting the calculated NOy from the observed NOy concentrations. The concentration of NOy at 13:00 on 22 August 2017 originating from lightning was estimated to be 1.11 ± 0.02 ppbv, which comprised 97 ± 2% of the total NOy concentration. The fractions of NO2 and NOz in the total NOy were 0.54 ± 0.01 and 0.46 ± 0.03, respectively. The NO concentration was below the detection limit. We firstly observed increase of concentrations of NOy originating from lightning by ground-based observation and demonstrated the quantitative estimates of LNOx using model-based calculation.

Original languageEnglish
Pages (from-to)133-150
Number of pages18
JournalJournal of Atmospheric Chemistry
Issue number2
Publication statusPublished - 2019 Jun 15


  • Ground-based observation
  • LNO
  • Lightning-induced nitrogen oxides
  • Mountain

ASJC Scopus subject areas

  • Environmental Chemistry
  • Atmospheric Science


Dive into the research topics of 'Ground-based observation of lightning-induced nitrogen oxides at a mountaintop in free troposphere'. Together they form a unique fingerprint.

Cite this