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| Titel |
An automatic snow station experiment in Western Dronning Maud Land, Antarctica |
| VerfasserIn |
O. Järvinen, M. Lepparanta |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250058857
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| Zusammenfassung |
| Snow and ice cover 98% of all surfaces in Antarctica and it is one of the principal
components of our global climate system. Snow properties easily respond to changes in
environmental conditions and therefore studying the spatio-temporal variations in the
physical properties of Antarctic snow cover is crucial. We present here results from a snow
station experiment recording the temperature evolution of the snow surface layer over one
year in two stations. The snow stations were installed in December 2009 to measure the snow
temperature at 15 different depths for one year, the deepest sensor being at 4 m at the moment
of installation. The stations were recovered in January 2011 and both were still fully
operational. It was the first time when this kind of experiment was successful in the
western Dronning Maud Land. The stations were located 50 km (station 1) and 10 km
(station 2) from the Finnish research station Aboa (73o 02.5’S, 013o24.4’W), 80
and 130 km south of the ice shelf edge. The temperature data are analyzed for the
annual temperature cycle of surface layer temperature, surface heat budget, and net
snow accumulation. The power spectra of temperature at the depth of 54 cm were
calculated for the whole measurement interval, and separately for the polar night and
polar day seasons. The daily cycle was strong during the polar day but disappeared
when the polar night started. The daily cycle is also seen when looking over the
whole measurement interval. Also physical characterization of the snow stratigraphy
was made at the installation sites at the start and end of the recordings, including
thickness, density, hardness (hand test), and grain size and shape (photographs from
crystals). Also the dielectric constant was measured using the Snow Fork (designed
and manufactured by Toikka Oy) to estimate the liquid water content (wetness). |
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