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- Creator:
- Ward, Jamie L ., Flanner, Mark G., Bergin, Mike, Dibb, Jack E., Polashenski, Chris M., Soja, Amber J., and Thomas, Jennie L.
- Description:
- Biomass burning produces smoke aerosols that are emitted into the atmosphere. Some smoke constituents, notably black carbon (BC), are highly effective light-absorbing aerosols (LAA). Emitted LAA can be transported to high albedo regions like the Greenland Ice Sheet (GrIS) and affect local snowmelt. In the summer, the effects of LAA in Greenland are uncertain. To explore how LAA affect GrIS snowmelt and surface energy flux in the summer, we conduct idealized global climate model simulations with perturbed aerosol amounts and properties in the GrIS snow and overlying atmosphere. The in-snow and atmospheric aerosol burdens we select range from background values measured on the GrIS to unrealistically high values. This helps us explore the linearity of snowmelt response and to achieve high signal-to-noise ratios. With LAA operating only in the atmosphere, we find no significant change in snowmelt due to the competing effects of surface dimming and tropospheric warming. Regardless of atmospheric LAA presence, in-snow BC-equivalent mixing ratios greater than ~60 ng/g produce statistically significant snowmelt increases over much of the GrIS. We find that net surface energy flux changes correspond well to snowmelt changes for all cases. The dominant component of surface energy flux change is solar energy flux, but sensible and longwave energy fluxes respond to temperature changes. Atmospheric LAA dampen the magnitude of solar radiation absorbed by in-snow LAA when both varieties are simulated. In general, the significant melt and surface energy flux changes we simulate occur with LAA quantities that have never been recorded in Greenland.
- Keyword:
- climate, Greenland Ice Sheet, black carbon, biomass burning, snowmelt, and surface energy balance
- Citation to related publication:
- Ward, J.L., et al. (2018). Modeled Response of Greenland Snowmelt to the Presence of Biomass Burning-Based Absorbing Aerosols in the Atmosphere and Snow. Journal of Geophysical Research: Atmospheres. 123, 6122– 6141. https://doi.org/10.1029/2017JD027878
- Discipline:
- Science
-
- Creator:
- Wozniak, Matthew C., Steiner, Allison L., and Solmon, Fabien
- Description:
- Pollen grains emitted from vegetation can rupture, releasing subpollen particles (SPPs) as fine atmospheric particulates. Previous laboratory research demonstrates potential for SPPs as efficient cloud condensation nuclei (CCN). We develop the first model of atmospheric pollen grain rupture, and implement the mechanism in regional climate model simulations over spring pollen season in the United States with a CCN-dependent moisture scheme. The source of SPPs (surface or in-atmosphere) depends on region and sometimes season, due to the distribution of relative humidity and rain. Simulated concentrations of SPPs are approximately 1-10 or 1-1,000 cm-3, depending on the number of SPPs produced per pollen grain (nspg). Lower nspg (103) produces a negligible effect on precipitation, but high nspg (106) in clean continental CCN background concentrations (100 CCN cm-3) shows SPPs suppress average seasonal precipitation by 32% and shift rates from heavy to light while increasing dry days. This effect is likely smaller for polluted air. pollen_rupture_precipitation_BASE_ensemble_daily.nc - data for BASE ensemble average pollen_rupture_precipitation_SPPHIGH_ensemble_daily.nc - data for SPPHIGH ensemble average pollen_rupture_precipitation_SPPLIT_ensemble_daily.nc - data for SPPLIT ensemble average
- Citation to related publication:
- Wozniak, M. C., Solmon, F., Steiner, A. L. (2018). Pollen Rupture and Its Impact on Precipitation in Clean Continental Conditions. Geophysical Research Letters, 45(14), 7156-7164. https://doi.org/10.1029/2018GL077692
- Discipline:
- Science
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- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Humburi Senni (Songhay family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Songhay, Humburi Senni, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
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- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Fulankiriya (Songhayfamily) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Songhay, Fulankiriya, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Bozo Jenama (Mande family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Mande, Bozo Jenama, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Moore (Gur family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Gur, Moore, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Yanda Dom (Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Yanda Dom, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Toro Tegu (Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Toro Tegu, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Tomo Kan(Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Tomo Kan, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
-
- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Toro So (Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Toro So, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities