A four-year record of the meteorological parameters, radiative and turbulent energy fluxes at the edge of the East Antarctic Ice Sheet, close to Schirmacher Oasis

2013 ◽  
Vol 26 (1) ◽  
pp. 93-103 ◽  
Author(s):  
H.S. Gusain ◽  
V.D. Mishra ◽  
M.K. Arora
Keyword(s):  
Heat Flux ◽  
Heat Source ◽  
Air Temperature ◽  
Meteorological Parameters ◽  
Ice Sheet ◽  
Turbulent Energy ◽  
Energy Fluxes ◽  
Glacier Surface ◽  
Katabatic Winds ◽  
Schirmacher Oasis

AbstractSurface energy fluxes of the ice sheet close to oases (ice-free land regions) are crucial in the case of retreating ice sheet and growing oasis areas. This study presents a four-year record of the meteorological parameters, radiative and turbulent energy fluxes at the edge of the Antarctic ice sheet, close to Schirmacher Oasis in Dronning Maud Land, East Antarctica from March 2007–February 2011. The energy fluxes were analysed for summer season, winter season and transition periods. High katabatic winds were observed during winter (seasonal mean 9.3 m s-1) as compared to other seasons. A high correlation (r2 = 0.89) was observed between the glacier surface temperature and air temperature, and regression relations were obtained for summer, winter and transition periods. The net radiative flux was the main heat source to the glacier during summer (46.8 W m-2) and heat sink during winter (-42.2 W m-2). Sensible heat flux (annual mean 32 W m-2) was the heat source and latent heat flux (annual mean -61 W m-2) was the heat sink to the glacier surface, averaged over all seasons. Comparison with other coastal or dry valley locations in Antarctica show that low humidity (50%), high katabatic winds (8.3 m s-1) and mild surface (-11.4°C) and air temperature (-10.2°C) contribute to high latent heat flux at the present study location.

scholarly journals Comparative study of the radiative and turbulent energy fluxes during summer and winter at the edge of the Antarctic ice sheet in Dronning Maud Land - East Antarctica

MAUSAM ◽  
2021 ◽  
Vol 62 (4) ◽  
pp. 557-566
Author(s):  
H.S. GUSAIN ◽  
V.D. MISHRA ◽  
AVINASH NEGI
Keyword(s):  
Heat Flux ◽  
Solar Radiation ◽  
Heat Source ◽  
Meteorological Parameters ◽  
Turbulent Energy ◽  
East Antarctica ◽  
Energy Fluxes ◽  
Glacier Surface ◽  
Dronning Maud Land ◽  
The Antarctic

Present study compares the estimated radiative and turbulent energy fluxes at the edge of the Antarctic ice sheet during summer and winter in Dronning Maud land, East Antarctica. Hourly snow meteorological parameters were recorded and analysed during winter months (May, June, July and August) of the year 2007 and summer months (November, December, January and February) of the year 2007-08 using Automatic Weather Station (AWS) on the glacier surface. Snow-meteorological parameters air temperature, relative humidity, wind speed, wind direction, incoming solar radiation, outgoing solar radiation, atmospheric pressure and glacier surface temperature were recorded by the AWS. An energy balance model was used to evaluate the surface energy fluxes from measured meteorological quantities for the summer and winter. Net radiative flux was observed the main heat source during summer with seasonal average of 98Wm-2 while sensible heat flux was observed main heat source during winter with seasonal average of 30 Wm-2. Latent heat flux was observed the main heat sink during both the season with seasonal average values of -86.7 Wm-2 for summer and -65.4 Wm-2 during winter. Sublimation was observed high during summer compare to winter.

scholarly journals Response of the Energy Balance on the Margin of the Greenland Ice Sheet to Temperature Changes

1990 ◽  
Vol 36 (123) ◽  
pp. 217-221 ◽  
Author(s):  
Roger J. Braithwaite ◽  
Ole B. Olesen
Keyword(s):  
Heat Flux ◽  
Energy Balance ◽  
Air Temperature ◽  
Sensible Heat Flux ◽  
Ice Sheet ◽  
Temperature Response ◽  
Greenland Ice Sheet ◽  
Energy Balance Model ◽  
Balance Model ◽  
Sensible Heat

AbstractDaily ice ablation on two outlet glaciers from the Greenland ice sheet, Nordbogletscher (1979–83) and Qamanârssûp sermia (1980–86), is related to air temperature by a linear regression equation. Analysis of this ablation-temperature equation with the help of a simple energy-balance model shows that sensible-heat flux has the greatest temperature response and accounts for about one-half of the temperature response of ablation. Net radiation accounts for about one-quarter of the temperature response of ablation, and latent-heat flux and errors account for the remainder. The temperature response of sensible-heat flux at QQamanârssûp sermia is greater than at Nordbogletscher mainly due to higher average wind speeds. The association of high winds with high temperatures during Föhn events further increases sensible-heat flux. The energy-balance model shows that ablation from a snow surface is only about half that from an ice surface at the same air temperature.

scholarly journals Comparison of turbulent structures and energy fluxes over exposed and debris-covered glacier ice

2020 ◽  
Vol 66 (258) ◽  
pp. 543-555 ◽  
Author(s):  
Lindsey Nicholson ◽  
Ivana Stiperski
Keyword(s):  
Heat Flux ◽  
Latent Heat ◽  
Similarity Theory ◽  
Sensible Heat Flux ◽  
Heat Fluxes ◽  
Temperature Fields ◽  
Sensible Heat ◽  
Energy Fluxes ◽  
Glacier Surface ◽  
Debris Cover

AbstractWe present the first direct comparison of turbulence conditions measured simultaneously over exposed ice and a 0.08 m thick supraglacial debris cover on Suldenferner, a small glacier in the Italian Alps. Surface roughness, sensible heat fluxes (~20–50 W m−2), latent heat fluxes (~2–10 W m−2), topology and scale of turbulence are similar over both glacier surface types during katabatic and synoptically disturbed conditions. Exceptions are sunny days when buoyant convection becomes significant over debris-covered ice (sensible heat flux ~ −100 W m−2; latent heat flux ~ −30 W m−2) and prevailing katabatic conditions are rapidly broken down even over this thin debris cover. The similarity in turbulent properties implies that both surface types can be treated the same in terms of boundary layer similarity theory. The differences in turbulence between the two surface types on this glacier are dominated by the radiative and thermal contrasts, thus during sunny days debris cover alters both the local surface turbulent energy fluxes and the glacier component of valley circulation. These variations under different flow conditions should be accounted for when distributing temperature fields for modeling applications over partially debris-covered glaciers.

scholarly journals Response of the Energy Balance on the Margin of the Greenland Ice Sheet to Temperature Changes

1990 ◽  
Vol 36 (123) ◽  
pp. 217-221 ◽  
Author(s):  
Roger J. Braithwaite ◽  
Ole B. Olesen
Keyword(s):  
Heat Flux ◽  
Energy Balance ◽  
Air Temperature ◽  
Sensible Heat Flux ◽  
Ice Sheet ◽  
Temperature Response ◽  
Greenland Ice Sheet ◽  
Energy Balance Model ◽  
Balance Model ◽  
Sensible Heat

AbstractDaily ice ablation on two outlet glaciers from the Greenland ice sheet, Nordbogletscher (1979–83) and Qamanârssûp sermia (1980–86), is related to air temperature by a linear regression equation. Analysis of this ablation-temperature equation with the help of a simple energy-balance model shows that sensible-heat flux has the greatest temperature response and accounts for about one-half of the temperature response of ablation. Net radiation accounts for about one-quarter of the temperature response of ablation, and latent-heat flux and errors account for the remainder. The temperature response of sensible-heat flux at QQamanârssûp sermia is greater than at Nordbogletscher mainly due to higher average wind speeds. The association of high winds with high temperatures during Föhn events further increases sensible-heat flux. The energy-balance model shows that ablation from a snow surface is only about half that from an ice surface at the same air temperature.

scholarly journals Analysis of a 3 year meteorological record from the ablation zone of Morteratschgletscher, Switzerland: energy and mass balance

2000 ◽  
Vol 46 (155) ◽  
pp. 571-579 ◽  
Author(s):  
J. Oerlemans
Keyword(s):  
Heat Flux ◽  
Sensible Heat Flux ◽  
Longwave Radiation ◽  
Solar Radiation Pressure ◽  
Turbulent Energy ◽  
Snow Accumulation ◽  
Shortwave Radiation ◽  
Glacier Surface ◽  
The Mean ◽  
Snow Temperature

AbstractSince 1 October 1995, an automatic weather station has been operated on the tongue of Morteratschgletscher, Switzerland. The station stands freely on the ice, and sinks with the melting glacier surface. It is located at 2100 m a.s.l., and measures air temperature, wind speed and direction, incoming and reflected solar radiation, pressure and snow temperature. A sonic ranger, mounted to stakes drilled into the ice, measures surface height from which melt rates and snow accumulation can be derived. In this paper the data for the period 1 October 1995 to 30 September 1998 are used to evaluate the surface energy balance. The turbulent energy fluxes are calculated with the bulk method. The turbulent exchange coefficient Ch is used as a control parameter. With Ch = 0.00127 the calculated melt equals the observed melt, which is 17.70 m w.e. over the 3 years. When averaged over the time when melting occurs (i.e. 35% of the time), the mean surface heat flux equals 191 W m−2. Net shortwave radiation contributes 177 W m−2, net longwave radiation −25 W m−2, the sensible-heat flux 31 W m−2 and the latent-heat flux 8 W m−2.

scholarly journals Morphology of the Ice-sheet Margin Near Thule, Greenland

1970 ◽  
Vol 9 (57) ◽  
pp. 303-324 ◽  
Author(s):  
Roger Leb. Hooke
Keyword(s):  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Upward Flow ◽  
Negative Mass ◽  
Glacier Surface ◽  
Wind Drift ◽  
Katabatic Winds ◽  
Basal Ice ◽  
Drifting Snow ◽  
Surface Ice

Three types of glacier margin are found along the edge of the Greenland ice sheet near Thule: ice cliffs, ramps and ice-cored moraines. Where the glacier margin is perpendicular to prevailing katabatic winds, drifting snow accumulates along it in stagnant wind-drill ice wedges. Upward flow of active ice behind these wedges causes ice originally near the base of the glacier to rise to the surface. Where this basal ice is free of debris, a gently sloping ramp develops. However, where the basal ice contains sufficient debris, a layer of till accumulates on the glacier surface. Ice beneath the till is insulated and a debris-capped ice ridge or ice-cored moraine forms, Ice cliffs occur where the ice-sheet margin is parallel to prevailing winds and is thus swept clear of drifting snow. Although the ice sheet in the Thule area appears to have had a negative mass balance for many years, all three types of glacier margin are believed to be equilibrium forms that can develop and persist on a glacier with a balanced mass budget.Foliation in wind-drift ice wedges generally dips down-glacier but foliation in active ice dips up-glacier. It is inferred that foliation in the wedges was once sedimentary stratification that has been tipped upward and locally overturned.

scholarly journals Morphology of the Ice-sheet Margin Near Thule, Greenland

1970 ◽  
Vol 9 (57) ◽  
pp. 303-324 ◽  
Author(s):  
Roger Leb. Hooke
Keyword(s):  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Upward Flow ◽  
Negative Mass ◽  
Glacier Surface ◽  
Wind Drift ◽  
Katabatic Winds ◽  
Basal Ice ◽  
Drifting Snow ◽  
Surface Ice

Three types of glacier margin are found along the edge of the Greenland ice sheet near Thule: ice cliffs, ramps and ice-cored moraines. Where the glacier margin is perpendicular to prevailing katabatic winds, drifting snow accumulates along it in stagnant wind-drill ice wedges. Upward flow of active ice behind these wedges causes ice originally near the base of the glacier to rise to the surface. Where this basal ice is free of debris, a gently sloping ramp develops. However, where the basal ice contains sufficient debris, a layer of till accumulates on the glacier surface. Ice beneath the till is insulated and a debris-capped ice ridge or ice-cored moraine forms, Ice cliffs occur where the ice-sheet margin is parallel to prevailing winds and is thus swept clear of drifting snow. Although the ice sheet in the Thule area appears to have had a negative mass balance for many years, all three types of glacier margin are believed to be equilibrium forms that can develop and persist on a glacier with a balanced mass budget.Foliation in wind-drift ice wedges generally dips down-glacier but foliation in active ice dips up-glacier. It is inferred that foliation in the wedges was once sedimentary stratification that has been tipped upward and locally overturned.

SECOND‐GRADE FLUID FLOW WITH POWER‐LAW HEAT FLUX AND A HEAT SOURCE

2013 ◽  
Vol 44 (8) ◽  
pp. 687-702 ◽  
Author(s):  
Tasawar Hayat ◽  
Sabir A. Shehzad ◽  
Muhammad Qasim ◽  
F. Alsaadi ◽  
Ahmed Alsaedi
Keyword(s):  
Heat Flux ◽  
Fluid Flow ◽  
Heat Source ◽  
Power Law ◽  
Second Grade ◽  
Second Grade Fluid ◽  
Grade Fluid ◽  
Power Law Heat Flux
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