Bulletin of Glaciological Research,3 ( ,*++ ) ++1ῌ 1 ῌJapanese Society of Snow and Ice Glaciological Research Project in Patagonia,**0ῌ ,**3 : Studies at Glaciar Perito Moreno, Hielo Patagónico Sur, in area of Hielo Patagónico Norte, and along the Pacific Coast Masamu ANIYA+,-. , Pedro SKVARCA , Shin SUGIYAMA , Tatsuto AOKI , Takane MATSUMOTO/0 , Ryo ANMA , Nozomu NAITO 1 , Hiroyuki ENOMOTO 2 , Kazuaki HORI3 , Sebastián MARINSEK , , Keiko KONYA +* , Takayuki NUIMURA ++ , Shun TSUTAKI+, , Kenta TONE +, and Gonzalo BARCAZA +- +Professor Emeritus, University of Tsukuba, Ibaraki -*/ῌ 2/1, , Japan ,Instituto Antártico Argentino, Cerrito +,.2 , C +*+* AAZ, Buenos Aires, Argentina - Institute of Low Temperature Science, Hokkaido University, Sapporo*0*ῌ *2+3 , Japan .College of Natural Sciences, Kanazawa University, Kanazawa 3,*ῌ ++3, , Japan / Centro de Investigación en Ecosistemas de la Patagonia, Coyhaique, Chile 0 Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki-*/ῌ 2/1, , Japan 1 Department of Global Environment Studies, Hiroshima Institute of Technology, Hiroshima1-+ῌ /+3- , Japan 2 Department of Civil Engineering, Kitami Institute of Technology, Kitami*3*ῌ 2/*1 , Japan 3 Department of Environmental Science and Technology, Meijo University, Nagoya.02ῌ 2/*, , Japan +* Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka,-1ῌ **0+ , Japan ++ Graduate Student, Graduate School of Environmental Studies, Nagoya University, Nagoya.0.ῌ 20*+ , Japan +, Graduate Student, Graduate School of Earth Environmental Sciences, Hokkaido University, Sapporo*0*ῌ *2+* , Japan +- Dirección de Aguas, Ministerio de Obras Públicas, Santiago, Chile (Received November+2 , ,*+* ; Revised manuscript accepted February . , ,*++ ) Abstract The Glaciological Research Project in Patagonia (GRPP),**0ῌ ,**3 was carried out with several objectives at Glaciar Perito Moreno of the Hielo Patagónico Sur (HPS), in the area of the Hielo Patagónico Norte (HPN) and along the Pacific coast. At Glaciar Perito Moreno, hot water drilling was carried out at about/ km upstream from the terminus, reaching the glacier bottom at ca./+/ m, in order to monitor subglacial water pressure. Good positive correlations among air temperature, subglacial water pressure and glacier flow speed were found. Based on+. C dating of tree and organic samples, it is proposed that Glaciar Perito Moreno made two Little Ice Age (LIA) advances at AD+0**ῌ +1**and ca. +-*ῌῌ +** y BP (AD +2,* /* ). Fan deltas located at the mouth of big rivers around Lago General Carrera (Buenos Aires) and Lago Cochrane (Pueyrredon), in the area east of the HPN, were investigated to elucidate their development. The variations of,+ outlet glaciers of the HPN elucidated from aerial surveys for ,**. / */ῌ ,**2/ *3 revealed an areal loss of 2 . 01 km, in four years. A general slowing down of retreats was observed with a few exceptions. Meteorological measurements at Glaciar Exploradores of the HPN from,**/ to ,**3 indicate that air temperature ranged from +1 . .῍ῌ῍ to +* . / . The total annual precipitation was about-*** mm. Glacier surface melt was observed at two spots. Sediment and water discharges from the glacier showed that while water discharge fluctuated a lot, suspended sediment concentration was rather stable in summer. A single channel seismic profiling during the JAMSTEC MR*2ῌ *0 cruise identified a probable submerged moraine formed before the last glacial maximum (LGM) in the Golfo de Penas, south of Taitao Peninsula. Piston coring along the Chilean coast further indicates that ice-rafted debris recorded the LGM and earlier Late Pleistocene events of the glacial advance. Key words: Patagonia Icefield, Glaciar Perito Moreno, glacier variation, Glaciar Exploradores, Mirai*2ῌ *0 cruise 2 Bulletin of Glaciological Research countries, Chile and Argentina (Fig.+ ). It stretches +.Introduction over ca./.* km with the width ranging from ca. 2 km to0* km. At present it comprises two separate ice This is a general, summary report of ‘The Glaci- bodies, Hielo Patagónico Norte (Fig., ) with an area of ological Research Project in Patagonia’ (GRPP),**0ῌ ca. -3/* km, (Riveraet al. , ,**1 ) and Hielo Patagónico ,**3(Project No. +2,/+**, ), which was the continuation Sur (Fig. - ) with an area of ca. +,//* km, in ,**3 (P. of the project that started in+32- and has been Skvarca, pers. comm.). Together it is the largest tem- making great contributions to the better understand- perate ice body in the Southern Hemisphere. The ing of the Hielo Patagónico (Patagonia Icefield,i.e. , HPN has,2 outlet glaciers, while the HPS has .2 outlet Nakajima,+32/ , +321 ; Naruse and Aniya, +33, , +33/ ; glaciers. The HPS has the largest glacier in the Ameri- Aniya and Naruse,,**+ a, ,**+ b; Aniyaet al. , ,**/ ; cas, Glaciar Pío XI with an area of ca. +,/* km, . Two Aniyaet al. ,,**1 b). other glaciers, Viedma and Upsala exceed2** km, in In the course of fieldwork, the initial objectives of area. The outlet glaciers have been in general re- the project had to be slightly modified and the final treating since+3./ , with two exceptions in the HPS. objectives became as follows: Glaciar Pío XI has been more or less advancing, and (+ ) Mechanism of short-term flow speed variation of Glaciar Perito Moreno has been stable (Aniyaet al. , Glaciar Perito Moreno, Hielo Patagónico Sur (HPS,+331 ). Southern Patagonia Icefield), The variation of,+ major outlet glaciers of the (, ) Little Ice Age (LIA) advance of Glaciar Perito HPN has been closely monitored since+3./ (i.e. , Aniya Moreno,+33, , ,**+ , ,**1 ; Aniya and Wakao, +331 ) and varia- (- ) Lake-level changes and fan delta evolution of tions were updated to,**2 / *3 from aerial surveys in glacial lakes in the area of the Hielo Patagónico Norte this project. The variations of.2 outlet glaciers of (HPN, Northern Patagonia Icefield), the HPS were elucidated using a Landsat mosaic and (. ) Continued monitoring of glacier variations of the aerial photographs for+3./ῌ +320 by Aniyaet al. ( +331 ), HPN, and and some of them have been updated using satellite (/ ) Late Pleistocene glacial advances in Patagonia images such as Radarsat (Aniyaet al. ,,*** ), Landsat recorded in the ice-rafted debris from o# shore piston (Skvarca and De Angelis, ,**, ), and ALOS (Aniya coring along the Chilean coast.et al. ,,**2 , ,**3 ). In the original proposal, we listed another objec- tive: ‘A mass balance study at Glaciar Ste# en of the ,,. Glaciar Perito Moreno, HPS HPN’, through ice coring, flow velocity and ice thick- Glaciar Perito Moreno is located at/*ῌ -*ῌ S and ness measurements and meteorological observations.1-ῌ W on the east side of the HPS (see Fig. - ), with an A mass balance study at an outlet glacier of the area of,/2 km, and an AAR (Accumulation Area Ra- Patagonia Icefield is one of the major topics that still remain to be challenged, because due to the harsh environment and di$ cult access, the continuous field measurements of snowfall/ablation in the accumula- tion area have not been carried out yet. The source area of Glaciar Ste# en, the third largest in the HPN, lies to the west of Cerro Colonia (--0/ m), the second highest mountain in the HPN. However, due to many unforeseen di$ culties, we had to regrettably give up this objective. On the other hand, a project of o# shore piston coring, SeaBeam and single-channel seismic profilings along the Chilean Patagonia coast was added because this project, which one of the CIs, Anma, proposed to the JAMSTEC (Japan Agency of Marine-Earth Sci- ence and Technology) using Research Vessel ‘Mirai’ , was approved for,**2ῌ ,**3 . ,. Study Area ,+. Hielo Patagónico The Hielo Patagónico is located at the southwest- ern end of South America, between latitudes .0ῌ -*ῌ and/+ῌῌ -*ῌῌ S along longitude 1- -* W, straddling two Fig.+ . Location of Hielos Patagónicos, South America. ANIYA et al. 3 Fig., . Satellite image of the Hielo Patagónico Norte, with glacier names (Landsat TM mosaic, March+, , ,**+). A rectangle indicates the area of Glaciar Exploradores where meteorological and hydrolog- ical measurements were carried out. Fig.- . Hielo Patagónico Sur (Landsat TM mosaic, March+, , ,**+ ), with the study area, Glaciar Perito Moreno indicated. tio) of* . 1- (Aniyaet al. , +330 ). It terminates in Lago Argentino with two calving fronts, one in Brazo Rico to the south and the other in Canal de los Témpanos to tion, extensive glaciological and geophysical studies the north. The glacier is known for repeated ad- were carried out on glacier dynamics and mass bal- vances and subsequent snout collapses that started ance (e.g. , Rott et al. ,+332 ; Stuefer, +333 ; Stuefer et al. , around the turn of the,*th century (e.g. , Mercer, +30, ; ,**1 ), as well as glacier flow by radar interferometry Aniya and Skvarca,+33, ). Since a neighboring gla- (Michel and Rignot, +333 ). The contrasting behavior cier to the north, Glaciar Ameghino, whose accumula- of Glaciar Perito Moreno and Glaciar Ameghino was tion area is situated in the same topographic setting discussed (e.g. , Nichols and Miller,+3/, ; Warren, +33. ). as Glaciar Perito Moreno, has been retreating, we do not know thoroughly yet the causes and mechanisms ,-. Glaciar Exploradores, HPN of rapid, repeating advances and retreats (i.e. , Nichols Glaciar Exploradores is located at.0ῌ -*ῌ S and and Miller,+3/, ; Aniyaet al. , +331 ) 1-ῌ +*ῌ W on the north edge of the HPN (see Fig. , ). Since the access to Glaciar Perito Moreno is rela- The accumulation area lies on the north wall of Monte tively easy, many studies were carried out at this San Valentin, the highest mountain in Patagonia with glacier, and the GRPP has been carrying out research-3+* m, and hence it is not directly connected to the here since+33* , in order to understand the mechanism icefield. The area is ca.+,+ km, with an AAR of * . 00 of the repeated advances and retreats (e.g. , Aniya and (Aniya,+322 ). The snout is heavily covered with debris Skvarca,+33, ; Naruseet al. , +33, ; Naruse et al.