In:
Environmental Science: Atmospheres, Royal Society of Chemistry (RSC), Vol. 2, No. 6 ( 2022), p. 1411-1427
Kurzfassung:
Photolysis rate constants ( j -values) play a crucial role in atmospheric chemistry modelling, but capturing the variability in local conditions needed for their accurate simulation is computationally challenging. One approach is to adjust modelled clear-sky estimates using ratios of measured-to-modelled j -values of a reference photolysis, typically j (NO 2 ) or j (O 1 D). However, application of such adjustments to other photolysis reactions introduces uncertainty. Using spectral radiometer data from the UK, this study examines how hourly measurement driven adjustment factors (MDAF) across a set of 12 photolysis reactions group together using cluster analysis, and evaluates the uncertainties in using j (NO 2 ) and j (O 1 D)-derived MDAF values to adjust modelled j -values of other photolysis reactions. The NO 2 -MDAF reference is suitable for adjusting photolysis reactions that absorb at λ 〉 360 nm (HONO, methylglyoxal, ClNO 2 , ClONO 2 → Cl), which are largely independent of solar zenith angle and total ozone column ( 〈 31% error). In particular, NO 2 -MDAF is a good reference for j (HONO) and j (ClNO 2 ). The O 1 D-MDAF performed better at adjusting modelled j -values for species that predominantly photodissociate at λ 〈 350 nm, such as HNO 3 , H 2 O 2 , CH 3 CHO, HCHO → H, HCHO → H 2 and ClONO 2 → ClO (errors ≤ 30%). However, j (O 1 D) radiometers require more data processing to account for local conditions. The maximum error determined using NO 2 -MDAF was within a factor of two (91% for j (H 2 O 2 )), which may still be acceptable in some instances. It is important that MDAFs are used to improve accuracy and uncertainty in simulated j -values caused by variation in local conditions.
Materialart:
Online-Ressource
ISSN:
2634-3606
Sprache:
Englisch
Verlag:
Royal Society of Chemistry (RSC)
Publikationsdatum:
2022
ZDB Id:
3057711-1
