TY  - JOUR
AU  - Meeta Cesler-Maloney, William R. Simpson
PY  - 2022//
TI  - Differences in Ozone and Particulate Matter Between Ground Level and 20 m Aloft are Frequent During Wintertime Surface-Based Temperature Inversions in Fairbanks, Alaska
KW  - Alaska inversion ozone PM2.5 pollution vertical
N2  - During winter in Fairbanks, Alaska, fine particulate matter (PM2.5) accumulates to large concentrations at breathing level; yet little is known about atmospheric composition aloft. To investigate vertical differences of pollutants, we measured PM2.5 and ozone (O3) at 3 and 20 m above ground level (AGL) in Fairbanks during winter (November 2019–March 2020). We measured temperature and PM2.5 at 3, 6, 9, and 11 m AGL on a tower to quantify surface-based temperature inversions (SBIs) and near-surface PM2.5 gradients. We defined SBIs as data with an 11 m minus 3 m temperature difference greater than 0.5°C. We observed the largest differences in PM2.5 and O3 when SBIs were present. During SBIs, PM2.5 accumulated to large concentrations at 3 m but to a lesser extent at 20 m, demonstrating reduced vertical mixing. During SBIs, the median PM2.5 concentration was 4.8 μg m−3 lower at 20 m than at 3 m. When PM2.5 concentrations were large at 3 m, O3 was often completely chemically removed (titrated) but was still present at 20 m. During SBIs, the O3 mixing ratio was more than 2 nmol mol−1 larger at 20 m than at 3 m in 48% of the data. Results show that during SBIs, pollution in Fairbanks is mixed to altitudes below 20 m AGL and that the oxidation regime of the atmosphere changes from 3 to 20 m AGL as large differences in O3 mixing ratios were measured during SBIs.
SN  - 2169-8996
UR  - http://dx.doi.org/10.1029/2021JD036215
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=8503), last updated on Wed, 03 Jul 2024 18:52:42 +0200
ID  - MeetaCesler-Maloney2022
ER  -