A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice
The bulk aerodynamic transfer coefficients for sensible (C sub H) and latent (C sub E) heat over snow and sea ice surfaces are necessary for accurately modeling the surface energy budget but are very difficult to measure. This report therefore presents a theory that predicts C sub H and C sub E as f...
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ftdtic:ADA174089 2023-05-15T16:37:30+02:00 A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice Andreas,Edgar L COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH 1986-09 text/html http://www.dtic.mil/docs/citations/ADA174089 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA174089 en eng http://www.dtic.mil/docs/citations/ADA174089 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Atmospheric Physics Snow Ice and Permafrost Thermodynamics *SNOW *HEAT FLUX *SEA ICE TRANSFER FUNCTIONS AIR INTERFACES ATMOSPHERIC TEMPERATURE SURFACE ROUGHNESS TURBULENCE LATENT HEAT MATHEMATICAL PREDICTION COEFFICIENTS LENGTH DIFFUSION COEFFICIENT SCALAR FUNCTIONS MOISTURE DRAG ENTHALPY EXCHANGE ATMOSPHERE MODELS WATER VAPOR HEAT TRANSFER COEFFICIENTS Roughness length Heat exchange Moisture exchange Heat budget Air ice interfaces PE61102A AST24 WU002 Text 1986 ftdtic 2016-02-21T02:41:11Z The bulk aerodynamic transfer coefficients for sensible (C sub H) and latent (C sub E) heat over snow and sea ice surfaces are necessary for accurately modeling the surface energy budget but are very difficult to measure. This report therefore presents a theory that predicts C sub H and C sub E as functions of the wind speed and a surface roughness parameter. The crux of the model is establishing the interfacial sublayer profiles of the scalars, temperature and water vapor, over aerodynamically smooth and rough surfaces. These interfacial sublayer profiles are delivered from surface-renewal model in which turbulent eddies continually sweep down to the surface, transfer scalar contaminants across the interface by molecular diffusion, and then burst away. Matching the interfacial sublayer profiles with the usual semilogarithmic inertial sublayer profiles yields the roughness lengths for temperature and water vapor. With these and a model for the drag coefficient over snow and sea ice based on actual measurements, the transfer coefficients are predicted. C sub E is always a few percent larger than C and H. Both decrease monotonically with increasing wind speed for speeds above 1 m/s, both increase at all winds speeds as the surface gets rougher. Both, nevertheless, are almost between 0.0010 and 0.0015. Text Ice permafrost Sea ice Defense Technical Information Center: DTIC Technical Reports database |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Atmospheric Physics Snow Ice and Permafrost Thermodynamics *SNOW *HEAT FLUX *SEA ICE TRANSFER FUNCTIONS AIR INTERFACES ATMOSPHERIC TEMPERATURE SURFACE ROUGHNESS TURBULENCE LATENT HEAT MATHEMATICAL PREDICTION COEFFICIENTS LENGTH DIFFUSION COEFFICIENT SCALAR FUNCTIONS MOISTURE DRAG ENTHALPY EXCHANGE ATMOSPHERE MODELS WATER VAPOR HEAT TRANSFER COEFFICIENTS Roughness length Heat exchange Moisture exchange Heat budget Air ice interfaces PE61102A AST24 WU002 |
spellingShingle |
Atmospheric Physics Snow Ice and Permafrost Thermodynamics *SNOW *HEAT FLUX *SEA ICE TRANSFER FUNCTIONS AIR INTERFACES ATMOSPHERIC TEMPERATURE SURFACE ROUGHNESS TURBULENCE LATENT HEAT MATHEMATICAL PREDICTION COEFFICIENTS LENGTH DIFFUSION COEFFICIENT SCALAR FUNCTIONS MOISTURE DRAG ENTHALPY EXCHANGE ATMOSPHERE MODELS WATER VAPOR HEAT TRANSFER COEFFICIENTS Roughness length Heat exchange Moisture exchange Heat budget Air ice interfaces PE61102A AST24 WU002 Andreas,Edgar L A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
topic_facet |
Atmospheric Physics Snow Ice and Permafrost Thermodynamics *SNOW *HEAT FLUX *SEA ICE TRANSFER FUNCTIONS AIR INTERFACES ATMOSPHERIC TEMPERATURE SURFACE ROUGHNESS TURBULENCE LATENT HEAT MATHEMATICAL PREDICTION COEFFICIENTS LENGTH DIFFUSION COEFFICIENT SCALAR FUNCTIONS MOISTURE DRAG ENTHALPY EXCHANGE ATMOSPHERE MODELS WATER VAPOR HEAT TRANSFER COEFFICIENTS Roughness length Heat exchange Moisture exchange Heat budget Air ice interfaces PE61102A AST24 WU002 |
description |
The bulk aerodynamic transfer coefficients for sensible (C sub H) and latent (C sub E) heat over snow and sea ice surfaces are necessary for accurately modeling the surface energy budget but are very difficult to measure. This report therefore presents a theory that predicts C sub H and C sub E as functions of the wind speed and a surface roughness parameter. The crux of the model is establishing the interfacial sublayer profiles of the scalars, temperature and water vapor, over aerodynamically smooth and rough surfaces. These interfacial sublayer profiles are delivered from surface-renewal model in which turbulent eddies continually sweep down to the surface, transfer scalar contaminants across the interface by molecular diffusion, and then burst away. Matching the interfacial sublayer profiles with the usual semilogarithmic inertial sublayer profiles yields the roughness lengths for temperature and water vapor. With these and a model for the drag coefficient over snow and sea ice based on actual measurements, the transfer coefficients are predicted. C sub E is always a few percent larger than C and H. Both decrease monotonically with increasing wind speed for speeds above 1 m/s, both increase at all winds speeds as the surface gets rougher. Both, nevertheless, are almost between 0.0010 and 0.0015. |
author2 |
COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH |
format |
Text |
author |
Andreas,Edgar L |
author_facet |
Andreas,Edgar L |
author_sort |
Andreas,Edgar L |
title |
A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
title_short |
A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
title_full |
A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
title_fullStr |
A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
title_full_unstemmed |
A Theory for the Scalar Roughness and the Scalar Transfer Coefficients over Snow and Sea Ice |
title_sort |
theory for the scalar roughness and the scalar transfer coefficients over snow and sea ice |
publishDate |
1986 |
url |
http://www.dtic.mil/docs/citations/ADA174089 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA174089 |
genre |
Ice permafrost Sea ice |
genre_facet |
Ice permafrost Sea ice |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA174089 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766027791380250624 |