Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY)
Biomass burning (BB) produces large quantities of carbonaceous aerosol (black carbon and organic aerosol, BC and OA, respectively), which significantly degrade air quality and impact climate. BC absorbs radiation, warming the atmosphere, while OA typically scatters radiation, leading to cooling. How...
| Main Authors: | , , , , , , , , , , , , , , , , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
American Geophysical Union (AGU)
2021
|
| Online Access: | https://hdl.handle.net/1721.1/138425 |
| _version_ | 1826216738183708672 |
|---|---|
| author | Carter, Therese S Heald, Colette L Cappa, Christopher D Kroll, Jesse H Campos, Teresa L Coe, Hugh Cotterell, Michael I Davies, Nicholas W Farmer, Delphine K Fox, Cathyrn Garofalo, Lauren A Hu, Lu Langridge, Justin M Levin, Ezra JT Murphy, Shane M Pokhrel, Rudra P Shen, Yingjie Szpek, Kate Taylor, Jonathan W Wu, Huihui |
| author2 | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Carter, Therese S Heald, Colette L Cappa, Christopher D Kroll, Jesse H Campos, Teresa L Coe, Hugh Cotterell, Michael I Davies, Nicholas W Farmer, Delphine K Fox, Cathyrn Garofalo, Lauren A Hu, Lu Langridge, Justin M Levin, Ezra JT Murphy, Shane M Pokhrel, Rudra P Shen, Yingjie Szpek, Kate Taylor, Jonathan W Wu, Huihui |
| author_sort | Carter, Therese S |
| collection | MIT |
| description | Biomass burning (BB) produces large quantities of carbonaceous aerosol (black carbon and organic aerosol, BC and OA, respectively), which significantly degrade air quality and impact climate. BC absorbs radiation, warming the atmosphere, while OA typically scatters radiation, leading to cooling. However, some OA, termed brown carbon (BrC), also absorbs visible and near UV radiation; although, its properties are not well constrained. We explore three aircraft campaigns from important BB regions with different dominant fuel and fire types (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen [WE-CAN] in the western United States and ObseRvations of Aerosols above CLouds and their intEractionS and Cloud-Aerosol-Radiation Interactions and Forcing for Year downwind of southern Africa) and compare them with simulations from the global chemical transport model, GEOS-Chem using GFED4s. The model generally captures the observed vertical profiles of carbonaceous BB aerosol concentrations; however, we find that BB BC emissions are underestimated in southern Africa. Our comparisons suggest that BC and/or BrC absorption is substantially higher downwind of Africa than in the western United States and, while the Saleh et al. (2014, https://doi.org/10.1038/ngeo2220) and FIREX parameterizations based on the BC:OA ratio improve model-observation agreement in some regions, they do not sufficiently differentiate absorption characteristics at short wavelengths. We find that photochemical whitening substantially decreases the burden and direct radiative effect of BrC (annual mean of +0.29 W m−2 without whitening and +0.08 W m−2 with). Our comparisons suggest that whitening is required to explain WE-CAN observations; however, the importance of whitening for African fires cannot be confirmed. Qualitative comparisons with the OMI UV aerosol index suggest our standard BrC whitening scheme may be too fast over Africa. |
| first_indexed | 2024-09-23T16:52:19Z |
| format | Article |
| id | mit-1721.1/138425 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T16:52:19Z |
| publishDate | 2021 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/1384252023-02-09T18:04:48Z Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) Carter, Therese S Heald, Colette L Cappa, Christopher D Kroll, Jesse H Campos, Teresa L Coe, Hugh Cotterell, Michael I Davies, Nicholas W Farmer, Delphine K Fox, Cathyrn Garofalo, Lauren A Hu, Lu Langridge, Justin M Levin, Ezra JT Murphy, Shane M Pokhrel, Rudra P Shen, Yingjie Szpek, Kate Taylor, Jonathan W Wu, Huihui Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Massachusetts Institute of Technology. Department of Chemical Engineering Biomass burning (BB) produces large quantities of carbonaceous aerosol (black carbon and organic aerosol, BC and OA, respectively), which significantly degrade air quality and impact climate. BC absorbs radiation, warming the atmosphere, while OA typically scatters radiation, leading to cooling. However, some OA, termed brown carbon (BrC), also absorbs visible and near UV radiation; although, its properties are not well constrained. We explore three aircraft campaigns from important BB regions with different dominant fuel and fire types (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen [WE-CAN] in the western United States and ObseRvations of Aerosols above CLouds and their intEractionS and Cloud-Aerosol-Radiation Interactions and Forcing for Year downwind of southern Africa) and compare them with simulations from the global chemical transport model, GEOS-Chem using GFED4s. The model generally captures the observed vertical profiles of carbonaceous BB aerosol concentrations; however, we find that BB BC emissions are underestimated in southern Africa. Our comparisons suggest that BC and/or BrC absorption is substantially higher downwind of Africa than in the western United States and, while the Saleh et al. (2014, https://doi.org/10.1038/ngeo2220) and FIREX parameterizations based on the BC:OA ratio improve model-observation agreement in some regions, they do not sufficiently differentiate absorption characteristics at short wavelengths. We find that photochemical whitening substantially decreases the burden and direct radiative effect of BrC (annual mean of +0.29 W m−2 without whitening and +0.08 W m−2 with). Our comparisons suggest that whitening is required to explain WE-CAN observations; however, the importance of whitening for African fires cannot be confirmed. Qualitative comparisons with the OMI UV aerosol index suggest our standard BrC whitening scheme may be too fast over Africa. 2021-12-10T17:33:59Z 2021-12-10T17:33:59Z 2021-08-16 2021-12-10T17:28:24Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/138425 Carter, Therese S, Heald, Colette L, Cappa, Christopher D, Kroll, Jesse H, Campos, Teresa L et al. 2021. "Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY)." Journal of Geophysical Research: Atmospheres, 126 (15). en 10.1029/2021jd034984 Journal of Geophysical Research: Atmospheres Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union (AGU) Prof. Heald via Elizabeth Kuhlman |
| spellingShingle | Carter, Therese S Heald, Colette L Cappa, Christopher D Kroll, Jesse H Campos, Teresa L Coe, Hugh Cotterell, Michael I Davies, Nicholas W Farmer, Delphine K Fox, Cathyrn Garofalo, Lauren A Hu, Lu Langridge, Justin M Levin, Ezra JT Murphy, Shane M Pokhrel, Rudra P Shen, Yingjie Szpek, Kate Taylor, Jonathan W Wu, Huihui Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title | Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title_full | Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title_fullStr | Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title_full_unstemmed | Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title_short | Investigating Carbonaceous Aerosol and Its Absorption Properties From Fires in the Western United States (WE‐CAN) and Southern Africa (ORACLES and CLARIFY) |
| title_sort | investigating carbonaceous aerosol and its absorption properties from fires in the western united states we can and southern africa oracles and clarify |
| url | https://hdl.handle.net/1721.1/138425 |
| work_keys_str_mv | AT carterthereses investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT healdcolettel investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT cappachristopherd investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT krolljesseh investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT camposteresal investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT coehugh investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT cotterellmichaeli investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT daviesnicholasw investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT farmerdelphinek investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT foxcathyrn investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT garofalolaurena investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT hulu investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT langridgejustinm investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT levinezrajt investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT murphyshanem investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT pokhrelrudrap investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT shenyingjie investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT szpekkate investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT taylorjonathanw investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify AT wuhuihui investigatingcarbonaceousaerosolanditsabsorptionpropertiesfromfiresinthewesternunitedstateswecanandsouthernafricaoraclesandclarify |