富士山高標高域における浅部地温の通年観測
スポンサーリンク
概要
- 論文の詳細を見る
On September 2010, the Japanese mass media reported that permafrost had disappeared throughout the altitudes of 3300–3600 m asl. on the south-facing slope of Mt. Fuji (3776 m asl.) within 12 years because of climatic warming. However, no evidence (data and analyses) has been published in scientific journals. In this paper, we show ground freeze-thaw patterns above the tree line of Mt. Fuji based on recent year-round records of temperatures at shallow depths at 22 sites. The shallow ground temperatures became significantly warmer from the 2008–2009 period to the 2009–2010 period because the latter period had irregular snow accumulation at several sites and extremely sunny hot summer. The snow cover on Mt. Fuji generally prevented the ground from cooling rather than from warming. In addition, records for some locations show rapid ground warming in late summer, which accompanied heavy rainfall events. The mean annual temperatures at the ground surface on the south-facing slope were 1.5 to 3°C higher than those on the north-facing slope at the same altitude. Considering these characteristics, we interpret that the presence of permafrost is probable only at 5 sites on north- to west-facing windy locations above 3500 m asl., although studies in the 1970s suggest that the lower boundary lay at around 3000 m asl. on both north- and south-facing slopes. However, it is clear that, in the 1970s, the estimation of permafrost distribution on Mt. Fuji was based not on thaw depths at the end of thawing period (late September to mid October), but on those in the middle of thawing period (late July to August). The resulting overestimation of the permafrost distribution may have led to tales of extremely rapid permafrost degradation. Permafrost research on Mt. Fuji is still at its initial stage and long-term monitoring of ground temperatures is required to evaluate the impacts of changes of climate and volcanic activity on the surrounding environment.
著者
-
岩花 剛
北海道大学低温科学研究所
-
池田 敦
筑波大学生命環境科学研究科地球環境科学専攻
-
岩花 剛
北海道大学地球環境科学研究院
-
池田 敦
筑波大学生命環境系
-
末吉 哲雄
独立行政法人海洋研究開発機構地球環境変動領域
関連論文
- 2007年11月に北海道上ホロカメットク山で連続発生した雪崩
- ロシア北東域における異なる植生型から得られた表層花粉群 : 古植生復元の基礎資料として
- 東シベリア・ヤクーツク近郊のカラマツ林および森林攪乱地における活動層の熱・水収支特性
- レーザー距離計とディファレンシャルGPSを用いた地形測量データの精度検証 : スイスアルプスの岩石氷河を例に
- 凍土学の本場リポート : モスクワ大学地質学部地球雪氷学科における在外研究
- 富士山頂の凍土融解過程の検討 : ―永久凍土の長期変動に関する予察的研究―
- 永久凍土と活動層のリモートセンシング
- 富士山頂における3m深地温測定 (2008-2010年) : 永久凍土の存在確認と長期変化把握に向けて
- 赤石山脈三峰岳周辺の岩石氷河の^C年代
- 周氷河地形プロセス研究最前線
- 特集号「地球寒冷圏の地表変動―成果と課題―」
- 富士山頂の凍土融解過程の検討 : 永久凍土の長期変動に関する予察的研究
- 富士山高標高域における浅部地温の通年観測
- 大雪山系の風衝地における微気象観測
- 特集号「地球寒冷圏の地表変動-成果と課題-」 : 序説
- 富士山高標高域における浅部地温の通年観測 : 永久凍土急激融解説の評価も含めて
- 周氷河地形プロセス研究最前線
- 岩石氷河のかたち