Dome F

Japanese Antarctica Stations

Valkyrie Dome, also known as Dome Fuji (ドームふじ Dōmu Fuji), Dome F, or Valkyrjedomen, is located in the eastern part of Queen Maud Land at 77°30′S 37°30′E / 77.500°S 37.500°E / -77.500; 37.500. With an altitude of 3,810 m or 12,500 ft above sea level, it is the second-highest summit or ice dome of the East Antarctic ice sheet and represents an ice divide. Dome F is the site of Dome Fuji Station, a research station operated by Japan.

Discovery and naming

Valkyrie Dome is an ice dome rising to about 3,700 m in the eastern part of Queen Maud Land. In 1963-64, a Soviet Antarctic Expedition oversnow traverse crossed the north part of the dome at an elevation of over 3,600 meters. The feature was delineated by the SPRI-NSF-TUD airborne radio-echo sounding program, 1967-79. It was named Valkyrie Dome after the three Valkyrie of Norse mythology, who carried those that had fallen in battle to Valhalla.

Environment

Owing to its location on the Antarctic plateau and the high elevation, Valkyrie Dome is one of the coldest places on Earth. Temperatures rarely rise above -30°C in summer and can drop to -80°C in winter. The annual average air temperature is -54.3°C. The climate is that of a cold desert, with very dry conditions and an annual precipitation of about 25 millimeters of water equivalent, which falls entirely as ice crystals.[1]

Dome Fuji Station

Dome Fuji Station (ドームふじ基地 Dōmu Fuji Kichi) was established as "Dome Fuji observation base" (ドームふじ観測拠点 Dōmu Fuji Kansoku Kyoten) in January 1995. Its name was changed to "Dome Fuji Station " on April 1, 2004. Located at 77°19′S 39°42′E / 77.317°S 39.700°E / -77.317; 39.700, it is separated from Showa Station by about 1,000 km.

Glaciology

Deep ice core drilling at Valkyrie Dome was started in August 1995, and in December 1996 a depth of 2503 m was reached. This first core covers a period back to 340,000 years.[2][3]

The core quality from the Dome Fuji station, East Antarctica, is excellent even in the brittle zone from 500 to 860 m deep, where the ice is fragile during the 'in situ' core-cutting procedure.[4]

A second deep core was started in 2003. Drilling was carried out during four subsequent austral summers from 2003/2004 until 2006/2007, and by then a depth of 3035.22 m was reached. The drill did not hit the bedrock, but rock particles and refrozen water have been found in the deepest ice, indicating that the bedrock is very close to the bottom of the borehole. This core greatly extends the climatic record of the first core, and, according to a first, preliminary dating, it reaches back until 720,000 years.[5] The ice of the second Valkyrie Dome core is therefore the second-oldest ice ever recovered, only outranged by the EPICA Dome C core.

See also

References

  1. ↑ Watanabe, O.; and 11 others (2003). "General tendencies of stable isotopes and major chemical constituents of the Dome Fuji deep ice core". Global scale climate and environmental study through polar deep ice cores. Tokyo, Japan: National Institute of Polar Research. pp. 1–24.
  2. ↑ Dome-F Deep Coring Group (1998). "Deep ice-core drilling at Dome Fuji and glaciological studies in east Dronning Maud Land, Antarctica". Annals of Glaciology 27: 333–337.
  3. ↑ Kawamura, K.; and 17 others (2007). "Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years". Nature 448 (7156): 912–916. doi:10.1038/nature06015. PMID 17713531.
  4. ↑ Watanabe O, Kamiyama K, Motoyama H, Fujii Y, Shoji H, Satow K (Jun 1999). "The paleoclimate record in the ice core at Dome Fuji station, East Antarctica". Annu Glac. 29 (1): 176–8. doi:10.3189/172756499781821553.
  5. ↑ Motoyama, H. (2007). "The second deep ice coring project at Dome Fuji, Antarctica". Scientific Drilling 5: 41–43. doi:10.5194/sd-5-41-2007.

External links

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