地震前後におけるアルゴフロートを用いた海洋物理データ収集の研究

Tohoku region Pacific Ocean earthquake that occurred on March 11, 2011, resulted in extensive damage to vast areas rangingfrom the Tohoku to Kanto. However, at the time of an earthquake occurrence, the research vessel which was researching aboutmarine in earthquake hypocenter area adjacent seas is not confirmed, and ocean physical data like water temperature or salinityincluding ocean sound speed data required for echo sounder etc. cannot be acquired. Therefore, paying attention to the oceanautomatic profiling system (Argo system) in this study. Currently, Argo float has deployed about 3600 units in all the worldocean. Thus, it does not require large-scale observation system by research ship or tethered buoy. And we became able to graspthe marine structure of the scale of the earth immediately and easily.In this study, tried the acquisition of ocean physical data from the Argo data (water temperature, salinity, pressure) which unfolded before and after an earthquake near the focal area. As a result, In this earthquakes associated with the huge tsunami,rapid water temperature change has been confirmed in the vicinity of the sea after the earthquake.In addition, we analyzed about Sumatra offing earthquake accompanied by a similar huge Tsunami. Data was acquired fromtwo Argo floats which was observation in the seismic center area of ocean in 2005. As a result, a few days after the tsunamioccurrence, the thing by which the ocean physical data indicates a profile different from usual was suggested. Thus, to variationsin sudden marine environment, Argo system has been shown to be one of the effective database.SSS02-04発表要旨 / 日本地球惑星科学連合2015年大会（2014年5月24日～5月28日, 幕張メッセ国際会議場） / 日本惑星科学連合の許諾に基づき本文ファイルを掲

南極海における長距離音波伝播の越冬観測

In this paper, long-term observation in the AntarcticOcean using newly developed profiling float for deep sea"Deep NINJA", it succeeded in the deep sea profilingobservation under the winter sea ice for in about sixmonths for the first time in the world. From the dataobtained by this, it was analyzed for ocean soundthat depth of up 4,000 m in under winter ice inthe Antarctic Ocean. In the place deeper than2,000m that was not observed by the Argo float,it was found that variations in salinity and watertemperature is small, and does not affect thesound speed changes therefore. Moreover, in thesea surface, it succeeded in capturing clearseasonal variation in the freezing season and thethawing season. Therefore, the possibility thatthe sound propagation path and the signal levelis different depending on the season was found inthe shallow sea area of Antarctic Ocean. Fromthis, the possibility to affect the predation actionsof passive sonar or marine mammals is thought about.Poster 3P6-1, The 35th Symposium on Ultrasonic Electronics (3-5 December 2014, Meiji University, http://www.use-jp.org/j/) / 第35回超音波エレクトロニクスの基礎と応用に関するシンポジウ

結氷下の南極域における音速変化について

http://www.godac.jamstec.go.jp/darwin/cruise/mirai/mr12-05_leg2/

Overwintering observation of the long-distance sound wave propagation overwintering in the Antarctic Ocean

http://www.godac.jamstec.go.jp/darwin/cruise/mirai/mr12-05_leg2/