Monitoring of glacial dynamics in Johnson Dock (Livingston Island)
Entry ID: CNDA-ESP_ANT95-1628-E

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Summary
Abstract: In English:

The techiniques used to extrapolate seasonal behaviour to annual behaviour,
were:
- A Geodolite 504 to measure the position of each stake and 3 new
stakes were installed to obtain measurements along a hypothetical
ice flow device, which were deduced from data collected so far.
-To collect new samples of ash layers.
-To take pictures of the ice cliffs using the same photogrammetric camera
from fixed points with well-known coordinates, one year later. A
photogrammetric model has been elaborated to obtain the thickness and ice front
position from these stereoscopic pictures.The data collected throughout these
campaigns have contributed to the knowledge of the annual and seasonal ice
flow, and their relationship between the ice dynamic and parameters such as the
equilibrium line, the snow line or the mass balance of Johnson glacier.

The main results are: A sharp increase of ice flow from ice device to ice
front, with annual velocities between 0.19 cm/day and 7.38 cm/day (28 m.), and
values of the ratio V.Seasonal/V.Annual between 0.68 and 9.67. About the mass
balance: the great ablation rate during the austral summer and the importance
of the snow drift by the wind as a mechanism of balance. The analysis of the
stereoscopic pictures by using the photogrammetric model will promote
knowledge of the glacier mechanism, calving, and also the seasonal and annual
changes in glacier geometry.

En Espanol:

Las experiencias para alargar el comportamiento estacional a comportamiento
anual fueron:
-Uso de un teodolito 504 para medir la posicion de cada estaca e instalacion
de
3 nuevas estacas con lo que se pudieron obtener medidas a lo largo de un
hipotetico dispositivo de flujo de hielo, deducido a partir de la recoleccion
de datos.
-Recoleccion de nuevas muestras de capas de cenizas.
-Fotografias de grietas de hielo usando la camara fotogrametrica desde puntos
fijos con coordenadas bien conocidas, un ano despues. Se ha elaborado un modelo
fotogrametrico para obtener el espesor y la posicion del frente de hielo a
partir de estas fotografias estereoscopicas.

Los datos tomados a lo largo de estas campanas han permito conocer el flujo
anual y estacional, y las relaciones entre la dinamica del hielo y los
parametros como la linea de equilibrio, la linea de nieve o el balance de masas
del glaciar Jonhson.Los principales resultados son: Un preciso incremento del
flujo de hielo desde el dispositivo al frente de hielo, con velocidades anuales
entre 0,19 cm/dia y 7,38 cm/dia (28m) y valores proporcionales velocidad
estacional/anual entre 0,68 y 9,67. Sobre el balance de masas: el gran indice
de ablacion durante el verano austral y la importancia de las ventiscas de
nieve como mecanismo de equilibrio. El analisis de las fotografias
estereoscopicas usando el modelo fotogrametrico permitira conocer el mecanismo
de desprendimientos del glaciar y tambien los cambios anuales y estacionales en
la geometria del glaciar.

Geographic Coverage
 N: -62.0 S: -63.0  E: -60.0  W: -62.0

Temporal Coverage
Start Date: 1995-02-15
Stop Date: 1996-02-15


Location Keywords
CONTINENT > ANTARCTICA > Antarctic Peninsula > Scotia Sea > South Shetland Islands > Livingston Island
GEOGRAPHIC REGION > POLAR


Data Resolution


Science Keywords
CRYOSPHERE >GLACIERS/ICE SHEETS >GLACIERS    [Definition]
CRYOSPHERE >SNOW/ICE >ICE DEPTH/THICKNESS    [Definition]
CRYOSPHERE >SNOW/ICE >ICE GROWTH/MELT    [Definition]
CRYOSPHERE >SNOW/ICE >ICE MOTION    [Definition]
CRYOSPHERE >SNOW/ICE >ICE VELOCITY    [Definition]
PALEOCLIMATE >ICE CORE RECORDS >ISOTOPES    [Definition]
PALEOCLIMATE >ICE CORE RECORDS >VOLCANIC DEPOSITS    [Definition]
CRYOSPHERE >GLACIERS/ICE SHEETS >ABLATION ZONES/ACCUMULATION ZONES    [Definition]


ISO Topic Category
CLIMATOLOGY/METEOROLOGY/ATMOSPHERE
GEOSCIENTIFIC INFORMATION
INLAND WATERS


Platform
ERS-1 >European Remote Sensing Satellite-1    [Information]
LANDSAT    [Information]
SPOT-1 >Systeme Probatoire Pour l'Observation de la Terre-1    [Information]
STEREOGRAPHIC PHOTOGRAPHS    [Information]


Instrument
CAMERAS    [Information]
THEODOLITE    [Information]
GAMMA RADIATION DETECTOR    [Information]


Keywords
MONIOTORING
GLACIER DYNAMICS
MASS BALANCE
PHOTOGRAMMETRIC CAMERAS
STAKES
GEODOLITES


Originating Center


Data Center
Departamento Geodinimica y Geofisica, Facultat de Geologia, Universidad de Barcelona    [Information]
Data Center URL: http://www.ub.es/geodgf/

Data Center Personnel
Name: JAUME CALVET
Phone: +3493402137
Fax: +34934021340
Email: calvetj at natura.geo.ub.es
Contact Address:
Dpto. Geodinamica y Geofisica
Facultad de Geologia
Universidad de Barcelona
c/ Marti Franquest s/n
City: Barcelona
Postal Code: 08028
Country: Spain



Distribution
Distribution_Media: CD-ROM;DAT
Distribution_Format: ASCII;BINARY


Personnel
ANTONIO BARRAGAN SANABRIA
Role: DIF AUTHOR
Phone: +34913495731
Fax: +34913495929
Email: a.barragan at igme.es
Contact Address:
Centro Nacional de Datos Antarticos
Instituto Geologico y Minero de Espana
c/Rios Rosas 23
City: Madrid
Postal Code: 28003
Country: SPAIN


JAUME CALVET
Role: TECHNICAL CONTACT
Role: INVESTIGATOR
Phone: +3493402137
Fax: +34934021340
Email: calvetj at natura.geo.ub.es
Contact Address:
Dpto. Geodinamica y Geofisica
Facultad de Geologia
Universidad de Barcelona
c/ Marti Franquest s/n
City: Barcelona
Postal Code: 08028
Country: Spain



Creation and Review Dates
DIF Creation Date: 2003-04-21
Last DIF Revision Date: 2008-07-24

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