Activities of the summer party of the 27th Japanese Antarctic Research Expedition in 1985-1986

The author reports the operation of the 27th Japanese Antarctic Research Expedition (JARE-27) in the 1985/1986 austral summer season. 50 members of JARE-27 and 4 Japanese observers on board the icebreaker SHIRASE, led by the present author, left Tokyo on November 14,1985. At Fremantle, Australia, we were ordered by the Japanese Government on December 2 to rescue the R/S NELLA DAN which was chartered by the Australian National Antarctic Research Expedition and had been ice-locked off the northwest coast of Enderby Land since the end of October 1985. After completing this new mission on December 16 in spite of hard ice condition, the ship arrived in Breid Bay on December 20. Transportation of 110t cargo and construction of a generator hut at Asuka Camp were carried out, and the ship left Breid Bay for Syowa Station on December 31,leaving the 8-man field party in the Sor Rondane Mountains region. From January 4 1986 to February 6,transportation of 760t cargo, construction work, and other work for preparation for wintering over were conducted at Syowa Station. The ship left Syowa Station on February 7 and arrived in Breid Bay again on February 11 for the pickup of the JARE-26 inland traverse party and the JARE-27 Sor Rondane Mountains field party. The ship came back to Tokyo Port on April 20,1986 via Port Louis in Mauritius and Singapore, carrying out the oceanographic observations en route. The following scientific activities were conducted during the summer operation of the JARE-27 : a) Field work; 1) geological, geomorphological, and geodetic observations in the central part of the Sor Rondane Mountains, 2) terrestrial biological investigations on the Soya Coast, 3) gravimetric survey and geomorphological field work on the Soya Coast; b) Shipboard activities; 1) marine biological research in and near the pack ice zone as part of the International Biological Investigations of Marine Antarctic Systems and Stocks (BIOMASS) program, 2) usual oceanographic observations, 3) sea gravity measurements, 4) ionospheric observations