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Rapid warming is likely increasing primary production and wildfire occurrence in the Arctic. Projected changes in the abundance and composition of carbonaceous aerosols during the summer are likely to impact atmospheric chemistry and climate, but our understanding of these processes is limited by sparse observations. Here, we characterize carbonaceous aerosol at two field sites, Toolik Field Station in the Interior and the Atmospheric Radiation Measurement facility at Utqiaġvik on the Arctic coast of Alaska, USA, through the summers of 2022 and 2023. We estimated particulate matter ≤2.5 micrometers (PM2.5) and particulate matter ≤10 micrometers (PM10) using laser light scattering (PurpleAir sensors) and examined total carbon (TC) and its organic carbon (OC) and elemental carbon (EC) fractions in total suspended particles (TSP). We also investigated the dominant sources of carbonaceous aerosol using air mass backward-trajectories from the National Oceanic and Atmospheric Administration (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and radiocarbon source apportionment of TC. We found TC concentrations were about twice as high in the Interior than on the coast and that modern sources were the dominant sources of carbonaceous aerosol at both Toolik (95–99%) and Utqiaġvik (86–89%), with minor contributions from fossil sources. Periods of significantly elevated PM, TC, OC, and EC concentrations coincided with major boreal forest fire activity in North America that brought smoke to the region. The radiocarbon signature of EC measured at Toolik during these wildfire smoke events indicated that over 90% of the EC originated from modern sources. Our measurements demonstrate changing aerosol concentrations in the Arctic during the summer, and emphasize the need for continuous atmospheric monitoring to evaluate and advance our understanding of this rapidly changing atmospheric environment. (Manuscript in prep)
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Characterization of summertime carbonaceous aerosol on the North Slope of Alaska (Toolik and Utqiaġvik), 2022–2023
Rapid warming is likely increasing primary production and wildfire occurrence in the Arctic. Projected changes in the abundance and composition of carbonaceous aerosols during the summer are likely to impact atmospheric chemistry and climate, but our understanding of these processes is limited by sparse observations. Here, we characterize carbonaceous aerosol at two field sites, Toolik Field Station in the Interior and the Atmospheric Radiation Measurement facility at Utqiaġvik on the Arctic coast of Alaska, USA, through the summers of 2022 and 2023. We estimated particulate matter ≤2.5 micrometers (PM2.5) and particulate matter ≤10 micrometers (PM10) using laser light scattering (PurpleAir sensors) and examined total carbon (TC) and its organic carbon (OC) and elemental carbon (EC) fractions in total suspended particles (TSP). We also investigated the dominant sources of carbonaceous aerosol using air mass backward-trajectories from the National Oceanic and Atmospheric Administration (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and radiocarbon source apportionment of TC. We found TC concentrations were about twice as high in the Interior than on the coast and that modern sources were the dominant sources of carbonaceous aerosol at both Toolik (95–99%) and Utqiaġvik (86–89%), with minor contributions from fossil sources. Periods of significantly elevated PM, TC, OC, and EC concentrations coincided with major boreal forest fire activity in North America that brought smoke to the region. The radiocarbon signature of EC measured at Toolik during these wildfire smoke events indicated that over 90% of the EC originated from modern sources. Our measurements demonstrate changing aerosol concentrations in the Arctic during the summer, and emphasize the need for continuous atmospheric monitoring to evaluate and advance our understanding of this rapidly changing atmospheric environment. (Manuscript in prep)
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- Award ID(s):
- 2041240
- PAR ID:
- 10615963
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- aerosols carbonaceous aerosols organic particles black carbon fire disturbance
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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Abstract Rapid warming is likely increasing primary production and wildfire occurrence in the Arctic. Projected changes in carbonaceous aerosols during the summer will impact atmospheric chemistry and climate, but our understanding of these processes is limited by sparse observations. Here, we characterize carbonaceous aerosol in Alaska, USA: Toolik Field Station in the Interior and the Atmospheric Radiation Measurement facility at Utqiaġvik on the Arctic coast, during the summers of 2022 and 2023. We estimated PM2.5and PM10concentrations using laser light scattering (PurpleAir sensors) and examined total carbon (TC) and its organic carbon (OC) and elemental carbon (EC) fractions in total suspended particles (TSP). We investigated the dominant sources of carbonaceous aerosol using air mass backward‐trajectories from the NOAA HYSPLIT model and radiocarbon source apportionment of TC. TC concentrations were about twice as high in the Interior compared to the coast, with contemporary sources dominating at both Toolik (95%–99%) and Utqiaġvik (86%–89%) over minor contributions from fossil sources. Elevated PM, TC, OC, and EC concentrations coincided with major boreal forest fire activity in North America that brought smoke to the region. The radiocarbon signature of EC measured at Toolik during these wildfire events indicated that over 90% of the EC came from contemporary sources. Our measurements demonstrate the potential for Arctic aerosol concentrations to respond significantly to climate warming‐induced changes to the landscape and emphasize the need for continuous atmospheric monitoring to advance our understanding of this rapidly changing environment.more » « less
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