Examining the atmospheric radiative and snow-darkening effects of black carbon and dust across the Rocky Mountains of the United States using WRF-Chem
<p>The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is run to quantify the in-snow and atmospheric radiative effects of black carbon (BC) and dust on a convective-allowing (4 km) grid for water year 2009 across a large area of the Rocky Mountains. The sno...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2020-09-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/20/10911/2020/acp-20-10911-2020.pdf |
| Summary: | <p>The Weather Research and Forecasting model coupled with Chemistry
(WRF-Chem) is run to quantify the in-snow and atmospheric radiative effects
of black carbon (BC) and dust on a convective-allowing (4 km) grid for water
year 2009 across a large area of the Rocky Mountains. The snow-darkening
effect (SDE) due to the deposition of these light-absorbing particles (LAPs)
on surface snow enhances snowmelt by 3 to 12 mm during late spring and early
summer, effectuating surface runoff increases (decreases) prior to (after)
June. Meanwhile, aerosol–radiation interactions (ARIs) associated with LAPs
generally dim the surface from incoming solar energy, introducing an energy
deficit at the surface and leading to snowpack preservation by 1 to 5 mm. Surface runoff alterations brought forth by LAP ARI are of
opposite phase to those associated with LAP SDEs, and the BC SDE drives a
majority of the surface energy and hydrological perturbations. More
generally, changes in snow water equivalent (SWE) brought forth by LAP
effects are more a result of perturbations to the surface energy budget
rather than changes in precipitation amount or type. It is also found that
perturbations to the surface energy budget by dust ARI can differ in sign
from those of BC ARI, with the former being positive, enhancing snow melting,
and changing runoff.</p> |
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| ISSN: | 1680-7316 1680-7324 |