30. Brooks, Melting Snow, River of Light

Abstract Previous model simulations indicate that in stratiform precipitation, the precipitation rate can increase by 7% in the melting layer through direct condensation onto melting snow and the resultant cooled rain. In the present study, a model simulation of stratiform precipitation in a wide cold frontal rainband indicates that the precipitation rate can also increase by 5% in the melting layer through accretion, by melting snow and rain, of additional cloud water produced by the latent cooling of the ambient air associated with melting snow. The contribution of the combined processes, and therefore the additional precipitation gained through the latent cooling of melting snow within the melting layer, may contribute as much as 10% to the precipitation rate in stratiform precipitation.

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Snow Cover and Melting Snow from ERTS Imagery

The Canadian Surveyor ◽

10.1139/tcs-1974-0030 ◽

1974 ◽

Vol 28 (2) ◽

pp. 128-134 ◽

Cited By ~ 3

Author(s):

Douglas L. Golding

Keyword(s):

Thin Film ◽

Snow Cover ◽

Return Period ◽

Infrared Radiation ◽

Cloud Cover ◽

Near Infrared ◽

Infrared Imagery ◽

Transient Phenomena ◽

Melting Snow ◽

Mountain Watersheds

To evaluate the usefulness of ERTS imagery for obtaining information on snow cover for small mountain watersheds, two specific objectives were set: (1) to determine if snowpack ablation due to chinooks can be detected on ERTS imagery, and (2) to determine if melting snow can be distinguished from snow that has not yet begun to melt. The length of ERTS return period and the frequency of cloud cover over the mountains in winter combined to make the ERTS system almost useless in studying transient phenomena of short-return period such as the chinook. Melting snow could be distinguished from snow that had not reached melting temperature. The latter appeared light toned on both visible and near-infrared imagery because of its high reflectivity in these portions of the spectrum. Melting snow, however, appeared dark on near-infrared imagery because much of the incident infrared radiation is absorbed by the thin film of water on the surface of the melting snow.

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Response of the longwave radiation over melting snow and ice to atmospheric warming

Journal of Glaciology ◽

10.1017/s0022143000002811 ◽

1997 ◽

Vol 43 (143) ◽

pp. 66-70 ◽

Cited By ~ 5

Author(s):

Antoon Meesters ◽

Michiel van den Broeke

Keyword(s):

Numerical Simulation ◽

Large Scale ◽

Longwave Radiation ◽

Surface Melting ◽

Absolute Temperature ◽

Scale Model ◽

Fourth Power ◽

Temperature Profiles ◽

Melting Snow ◽

Meso Scale

AbstractParameterizing the incoming longwave radiationL↓ in terms of the fourth power of the absolute temperature at the reference height is used in glaciology for several purposes. In this paper, the validity of this kind of parameterization is investigated for the Greenland ice sheer, both by observations and by numerical simulation with a meso-scale model, It is found that such a parameterization severely underestimates the increase ofL↓ in response to large-scale warming in an area where surface melting is important. This is explained by the systematic influence that is exerted on the shape of the temperature profiles by surface melting.

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On the Use of Bulk Aerodynamic Formulae Over Melting Snow

Hydrology Research ◽

10.2166/nh.1983.0016 ◽

1983 ◽

Vol 14 (4) ◽

pp. 193-206 ◽

Cited By ~ 55

Author(s):

R. Daniel Moore

Keyword(s):

Complex Terrain ◽

Roughness Length ◽

Melting Snow ◽

Linear Profiles ◽

Temperature And Humidity ◽

The Stability ◽

Log Linear ◽

Theoretical Analyses ◽

Neutral Case ◽

Scale Length

Bulk aerodynamic formulae which relate the turbulent exchanges of sensible and latent heat over melting snow to measurements of windspeed, temperature and humidity at one level can be derived from flux-gradient relationships and assumed log-linear profiles. Recent analyses of local advection over snow and wind flow over complex terrain suggest that the bulk aerodynamic formulae should apply in non-ideal field situations. The assumption that the scaling lengths for temperature and humidity equal the roughness length is problematic, since theoretical analyses indicate they should be much less than the roughness length. However, the effect of scale length inequality on the stability correction tends to compensate for the effect on the neutral-case transfer coefficient. Field experience indicates that the bulk aerodynamic formulae are adequate for use in energy balance estimates of daily or shorter term snowmelt.

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