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Cloud radiative effects of snow
Clouds that generate snow fall pose widespread radiative effects to the global surface energy budget (due to snow precipitation) as well as cloud radiative forcing (due to distinct radiative impacts of liquid and snow clouds) (source). Furthermore, once snow falls on the ground, the snow water equivalent (SWE) of a given area can vary widely affecting the outgoing longwave radiative flux of the surface (source), the albedo of the surface (source), and the latent heat flux of the surface (source).

Globally
Global impacts of snow can be divided into those effects that are due by snow cover and that are due to clouds that are composed of snow and liquid water, also known as cloud radiative forcings (source).

Clouds that are composed of ice have a higher albedo and optical depth than that of liquid clouds. For this reason, ice clouds and mixed phase clouds have a distinct cloud radiative effect compared to liquid clouds.

There is a high variability of ice and liquid mixing ratio in clouds observed between -38° and 0° where the Wegener-Bergeron-Findeisen process occurs, transferring supercooled liquid water content in clouds to ice crystals. This process governs the ice to liquid mixing ratio of clouds and hence can govern the cloud radiative effects of these mixed phase clouds. Furthermore, the orientation of the mixing of these clouds can be extremely variable with a range of well mixed homogeneous phases or very heterogeneous distributions of ice and liquid within the same cloud mass. This variability further complicates the cloud radiative effects based on upwelling longwave fluxes or downwelling shortwave fluxes.

The impacts of snow on radiative budget include three processes, precipitation, accumulation, and retention. Precipitation and cloud snow generation processes change the overall optical properties of clouds towards a higher albedo due to the higher ice content. These clouds then are dispersed as snow falls out of them accumulating on the ground. Snow that is retained creates a layer at the surface of infinite optical depth and high albedo. Furthermore, over time, this snow metamorphoses into ice, capping surface heat fluxes.

Regionally
Snowfall occurs on annual cycles in the midlatitudes, melting seasonally and being retained through the winter. However, in high altitude and high latitude regions, snow can be retained throughout the entire year with significant effects to the surface albedo of the specific region. In regions of sea ice, this can translate to an increase in sea ice thickness and hence a lower amount of heat flux is released from the ocean into the atmosphere.

In regions of high latitude or orographic effect, mixed phase clouds are common. The heterogeneities of these clouds complicate their representation of cloud radiative effects in global climate models. Clouds can be liquid capped with dendritic growth occurring beneath or can be well mixed in ice and liquid.

Sensible and latent heat fluxes from high latitude oceans have been observed and simulated to create precipitating mixed phase clouds with significant optical and radiative effects. In particular along the margins of the Arctic sea ice pack, where plastic deformation occurs in the ice sheet, cracks known as ice leads release heat from the ocean generating clouds and ultimately creating snow that falls onto the ice surface, further adding to ice thickness and surface albedo

Effects of blowing snow on radiative budget
Wind lofted snow or blowing snow is a secondary post precipitation process of spatial redistribution of snow mass. In particular, wind loading of snow plays a significant role in optical and radiative properties in the lower atmosphere of the polar regions. From ground based observations, layers of blowing snow have been seen to exist to 120 meters in height and have optical depths of 0.05 (optically thin) to 1.0 (optically thick, about 36% of energy passes through layers of this depth). Blowing snow is widespread in the polar desert and heavily influenced by strong surface winds such as katabatic winds observed in Antarctica. At the Halley Research Station, it has been seen that blowing snow events occur between 27% and 37% of the time (source).

Blowing snow has been shown to both reduce the amount of downwelling shortwave flux arriving at the surface as well as suppressing the amount of upwelling longwave flux, reducing the amount of surface cooling. Furthermore, surface based inversions where these blowing snow layers reside further decouples the radiative influences of the surface on the free atmosphere above. Radiative transfer models have shown that with increased blowing snow optical depth, top of the atmosphere longwave cooling is reduced on the scale of -5 W/m2

Alpine Glaciers
Layers of coal soot that are lofted from energy generation have been noted to accelerate warming of alpine ice sheets in many regions of the world (source). In particular, the addition of the low albedo soot increases the transition of shortwave solar heating into longwave thermal flux which causes small cavities to melt into the snow surface.

Prudhoe Bay Oil Fields
In early spring, soot particles generated by fossil fuel burning has been observed to be deposited on arctic snow. In particular, areas such as the Prudhoe Bay Oil Fields have been seen to be one of the major sources of black carbon responsible for reducing the surface albedo of the snow pack (source). Previous study has shown that black carbon generation in the region is due to gas flaring of gas and oil production byproducts.

Sources:
- https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013GL058932

- https://www.researchgate.net/publication/329628821_Identification_of_blowing_snow_particles_in_images_from_a_multi-angle_snowflake_camera

- https://www.researchgate.net/publication/235989875_Satellite_remote_sensing_of_blowing_snow_properties_over_Antarctica

- https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JD030623

- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC327163/

- https://www.independent.co.uk/environment/climate-change/layers-soot-coal-burning-melted-alpine-glaciers-even-cooler-climate-19th-century-8795396.html

- https://www.boem.gov/sites/default/files/about-boem/BOEM-Regions/Alaska-Region/Technical-Talks-Presentations/D1_Environmental_Pratt.pdf

- https://www.sfchronicle.com/nation/article/Oil-boom-sets-off-health-fears-in-Alaskan-Arctic-13124725.php

- https://iopscience.iop.org/article/10.1088/2515-7620/abb3b8/pdf

- https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JD028655

- https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2010GL046478

- https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2015JD023587

- https://acp.copernicus.org/preprints/acp-2020-232/acp-2020-232.pdf

- https://www.nature.com/articles/s41558-018-0296-5?WT.feed_name=subjects_environmental-impact

- https://www.researchgate.net/publication/289682576_Properties_and_potential_radiative_impacts_of_Antarctic_blowing_snow

- https://journals.ametsoc.org/jhm/article/19/8/1397/69181/Assessment-of-Radiative-Forcing-by-Light-Absorbing

- https://www.sciencedirect.com/topics/earth-and-planetary-sciences/cloud-radiative-forcing#:~:text=The%20cloud%2Dradiative%20forcing%20represents,to%20the%20presence%20of%20clouds.

- https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JD022538

- https://watermark.silverchair.com/1520-0469(1984)041_2836_roapip_2_0_co_2.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAvUwggLxBgkqhkiG9w0BBwagggLiMIIC3gIBADCCAtcGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMF2Mwlh4_hxJf5cqCAgEQgIICqN25h4ZeUD9dM6uQ0U8m1bdIzVvVfny-EevYzxmKg81YyCTJfGeY8PzEO_Thierf6MJDV-2cRJOozaDQZoBONICmIyalVFsWP4NyIxTiiCdt3mq-om6XmffaiIAnCGqJLTtCXYq1gYZG8KJa9AALeF-wAaJZFNOUOsmlErZHvrl5ADBAeLBfqGqtTQF16f-_XXRuDLQ0zLYTTFpc7D1c49u48Z5tX9rGVrv2TXQt3tQrb5j_lSuCppJjgczBtxvlXSOdO4FjbY-sgb1ppzVGEo_6oUDJyFWwwlKethbl-j4a6K7GtPyUttinXZA9yaZJOESXu7Ke1CZyO3H6upqlK7NY5cYkuDFvwZve4C2Vjd5fvUyh-RBNuIld2QY8Ia9V8a-JrGN1caNeEm3X40plvrMHRbH-bgjmO9RXmzVOHPkmLzlDND0SnLeR0PVi7Lf_9jrKPchmugviZmFF0gAVlzpRjpmCRP1U0L0KM46Ke_Sg9SG7SZF2_WlD59DLXYySw7PuD-JrZ6b_nlORS1bePcPwD1lKpmOo5ET_tqGzsPMTa_T-XNc81TtjmOkvTYNFJ-MFHBHxq8qaDk-wLsbe6Z9y2d49jfONvdVoI_pLfoZ-8qvIv2ERbcHg7tcgEOvi8NiOPD1SgMkG-NSbpKHulAEu4WU1u1__95AuRcbOx5VjKOR22eQTkIFwxAnRv-lwJ8UPgJT-WQdaIRrMCzN4xwY5z1H-7cqwMED6lkRT32C1qYRrJpIEnQvyAqcRLKWFEqpPyXhZOHvc-HfjBvD5JL3uIvJeQ4labXVUpfQgY6_lxKfMZnzMV_AY9Fu5dt_BFlSt_UmA6lKyBpBdJXOtRgTlTpO24pIw4brJrfG9Mj5Mg9a9TFiPf_b5406ICfctctb5-gnCGVCg

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