Reaction of ⍺-pinene with nitrate is a major contributor in secondary organic aerosol formation

  • 25 February 2022
Reaction of ⍺-pinene with nitrate is a major contributor in secondary organic aerosol formation

⍺-pinene is an organic compound of the terpene class, that is emitted in substantial amount by vegetation. ⍺-pinene reacts with NO3 in the atmosphere leading to low-volatility species which partly condense on existing aerosols, thereby generating secondary organic aerosols (SOA). A new study, funded by CPO’s Atmospheric Chemistry, Carbon Cycle, & Climate (AC4) program and published in the journal of Atmospheric Chemistry and Physics explores the contribution of ⍺-pinene and NO3 in the SOA budget.

Researchers from the University of California, Davis and Harvard University performed experiments in an atmospheric chamber to characterize the SOA and organic nitrogen formation from the reaction between ⍺-pinene and NO3. Contrary to previous chamber experiment results, the researchers found that the reaction of ⍺-pinene + NO3 can form high mass yields of SOA in an environment designed to mimic summer nights in the southeast United States. These results suggest that ⍺-pinene + NO3 significantly contributes to the SOA budget and likely constitutes a major removal pathway of reactive nitrogen from the lower troposphere at nighttime in mixed biogenic–anthropogenic areas. The results also highlight the importance of performing chamber experiments under conditions that more closely match those in the ambient atmosphere.

Access the research here »

For more information, contact Shiv Das.




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