Little Ice Age advances of Glaciar Perito Moreno, Hielo Patagónico Sur, South America

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1 Bulletin of Glaciological Research -* (,*+,) +2 Japanese Society of Snow and Ice 1 Little Ice Age advances of Glaciar Perito Moreno, Hielo Patagónico Sur, South America Masamu ANIYA and Pedro SKVARCA +, + Professor Emeritus, University of Tsukuba, Ibaraki -*/ 2/1,, Japan, Instituto Antártico Argentino, Cerrito +,2, C+*+* AAZ, Buenos Aires, Argentina (Received October +,,*++; Revised manuscript accepted January ++,,*+,) Abstract, Glaciar Perito Moreno, with an area of,/2 km, is located on the eastern side of the Hielo Patagónico Sur (Southern Patagonia Icefield) at about /*,3 S and 1- * W Currently, it terminates in Lago Argentino, thereby dividing the lake into Canal de los Témpanos to the north and Brazo Rico to the south The glacier has repeatedly made small advances and retreats in the,* th century; + however, it can be regarded as rather stable since the +3,* Based on C dating of,, wood and one organic samples, we inferred that Glaciar Perito Moreno made two Little Ice Age (LIA) advances, one at ca AD +0/* and the other about AD +2,* /* These two dates fit very well into the general framework of the LIA of the HPS Key words: Patagonia Icefield, Glaciar Perito Moreno, Little Ice Age (LIA) advance distinctive vegetation trimline on both sides of the + Introduction glacier, above which has developed a dense forest with trees a few hundred years old or more, while Glaciar Perito Moreno, with its beauty and easy below is a predominantly bare till-covered slope Alaccess, is one of the most well known glaciers in though it is apparent that this prominent vegetation Patagonia, and probably the most-studied glacier trimline was formed during a most recent major glaamong more than seventy outlet glaciers in Patagonia cier advance, there has been no definitive study that Many of these studies documented and discussed the has attempted to determine its age Only Aniya and variation of its terminus in the,* th century ( eg, Sato ( +33/ ) dated one tree killed by a lateral moraine of Reichert, +3+1 ; Heim, +30 ; Nichols and Miller, +3/, ; the advancing Glaciar Perito Moreno to be 2,* 3* yr Ra# o et al, +3/- ; Mercer, +30, ; Liss, +31* ; Aniya and BP (sample NU- -//) Also along the shore of Brazo Skvarca, +33, ; Warren, +33 ), while recent studies Rico, we can see a very distinctive, level vegetation focused more on the glacier dynamics and flow ( eg, trimline, below which many large (Diameter at Breast Naruse et al, +33, ; Naruse et al, +33/ ; Takeuchi et al, Height - DBH up to ca 2* cm) dead yet standing trees +330 ; Skvarca and Naruse, +331 ; Rott et al, +332; Michel as well as fallen trees are scattered on fan deltas and and Rignot, +333 ; Naruse et al,,**+; Stuefer et al, gentle slopes covered with soil, whose sizes are similar,**1; Ciappa et al,,*+*) Glaciar Perito Moreno started to those living trees above the trimline advancing around the turn of the,* th century, and The LIA advances and subsequent recession of since then it has repeatedly made small advances and the Patagonian glaciers have been studied at some retreats, thereby reaching the opposite bank, Pen- outlet glaciers For example, Harrison et al (,**1) reinsula Magallanes, and damming up the southern viewed LIA studies at eleven outlet glaciers of the lake, Brazo Rico (Mercer, +30, ) Based on aerial pho- Hielo Patagónico Norte (HPN; Northern Patagonia Ice tograph analyses and historical documents, the gla- field), concluding that glacier recession from the maxicier is regarded to have been more or less stable since mal positions began in the early +20* s +21* s Masiokas the +3,* s (Aniya and Skvarca, +33, ; Skvarca unpub- et al (,**3) made a comprehensive review of the LIA lished) in Patagonia, both of the HPN and the HPS (Hielo + Mercer ( +302), based on C dating of wood and Patagónico Sur; Southern Patagonia Icefield), thereby peat samples around the glacier, concluded that since pointing out a regional contrast: in the HPN the LIA ca *** yr BP the glacier cannot have been much maximum mostly occurred during the +3th century further forward than it is today There is a very whereas in the HPS it occurred one to three centuries

2 2 Bulletin of Glaciological Research earlier Some glaciers made two or more LIA advances before the,+st century (e g, Nichols and Miller, +3/+; Mercer, +30/; Marden and Clapperton, +33/; Aniya, +33/, +330; Aniya and Naruse, +333; Harrison and Winchester,,***; Aniya and Shibata,,**+; Aniya et al,,**1) However, we still need more studies at individual glaciers before a complete picture of the LIA advances in Patagonia can be established It is the purpose of this study to determine the age of the vegetation trimline and infer the LIA advance (s) of Glaciar Perito Moreno We took a total of,samples for +C dating, mostly wood pieces from standing or uprooted (in situ) trees that were killed directly or indirectly by the advancing glacier The conventional radiocarbon age was converted to AD using a calibration curve Telford et al (,**) criticized the use of the mean only for the interception method with a calibration curve to obtain a single date, quoting an example from -***ῌ/*** +C yr BP, because a calibration curve is often multimodal (resulting in multiple interceptions) and the method does not consider the standard deviation However, when we have many samples from the same area with the similar dates, they can be regarded pointing the same event that directly or indirectly caused sample s occurrence When there are multiple intercepts, we adopted a date that is similar or close to the others with singular dates, because since they are located very close to each other, it is very probable that they were killed by the same event at a similar time, Study Area: Hielo Patagónico and Glaciar Perito Moreno The Hielo Patagónico is located at the southwestern end of South America, between the latitudes 0ῌ-*ῌ and /+ῌ-*ῌS along the longitude 1-ῌ-*ῌW (Fig +, inset) It stretches over ca /* km with the width ranging from ca 2 km to 0* km At present it comprises two separate ice bodies, HPN with an area of ca -3/* km, (Rivera et al,,**1) and HPS with an area of ca +,//* km, in,**3 (Skvarca, unpublished) Together it is the largest temperate ice body in the Southern Hemisphere On the east side of the HPS at around /*ῌ,3ῌS and 1-ῌ*ῌW is located Glaciar Perito Moreno (Fig +), with an area of,/2 km, and an AAR (Accumulation Area Ratio) of *1- (Aniya et al, +330) Currently it has two calving fronts in Lago Argentino, one in Brazo Rico to the south and the other in Canal de los Témpanos to the north (Fig,) The behavior of Glaciar Perito Moreno with the repeated advances and subsequent snout collapses during the,*th and,+st centuries (eg, Mercer, +30,; Aniya and Skvarca, +33,; Stuefer et al,,**1) contrasts strongly with that of Glaciar Ameghino (GA in Fig,), a neighboring glacier to the immediate north, which has been steadily retreating although the accumulation area is situated in the same topo- Fig + Landsat TM mosaic of Hielo Patagónico Sur (March +,,,**+) and the location of Glaciar Perito Moreno (GMP), with an inset indicating the location of Hielo Patagónico (Patagonia Icefield) The extent of Fig, is indicated GF: Glaciar Frias LA: Lago Argentino Fig, Study area: Glaciar Perito Moreno, indicated on part of the Landsat TM mosaic of Hielo Patagónico Sur (March +,,,**+) GA: Glaciar Ameghino PM: Península Magallanes BS: Bajo de las Sombras BC: Bahía Catalana

3 Aniya et al 3 graphic setting as Glaciar Perito Moreno The contrasting behaviors of Glaciar Perito Moreno and Glaciar Ameghino have been noted by Nichols and Miller (+3/,) and Warren (+33) We do not know, however, the reason or cause for such contrasting behaviors, because there is no field measurement at the accumulation areas of these glaciers - Vegetation Trimline around Brazo Rico and Glaciar Perito Moreno Since we started sampling on the shore of Brazo Rico rather than at the glacier, we describe the trimline around Brazo Rico first The prominent vegetation trimline along the shore of Brazo Rico, located at ca,-/ m higher than the normal lake level (Fig -), was formed during the higher water caused by damming of advancing Glaciar Perito Moreno The vegetation above the trimline is the wood mainly composed of Nothofagus (Coigüe and Lenga) with a DBH larger than /* cm, some even reaching around 2* cm The soil is mostly of eolian origin deposited during the Holocene and ca -* ῌ* cm thick on the glaciated bedrock Because the area below the vegetation trimline is still largely devoid of vegetation, often of bare bedrock, the water must have stayed high for a prolonged time Although the trimline has probably existed for a long time, its present level was formed during the +3/ῌ/0 damming event when the lake level was highest, which was revealed by a comparison of the +31 and +302 aerial photographs taken by the Instituto Geográfico Militar (IGM) of Argentina In some areas below the vegetation trimline where the shore slope is gentle with soil, there are many large dead yet standing trees as well as fallen large tree trunks that were killed by water submersion during the high water Fig - Vegetation trimline on the southern shore of Brazo Rico and a fan delta where seven samples (#+,,, -,, +,, +- and +/) were taken from five dead standing trees Also shown is the tree of sample #2 (Photo taken from helicopter on Feb,/,,*+*) Fig The right valley slope of Glaciar Perito Moreno, showing a prominent vegetation trimline (Photo, Jan -,,**3) The dotted white line roughly indicates the boundary between the older and younger moraines Fig / Vegetation trimline on the right valley slope of Glaciar Perito Moreno Looking down the area toward Brazo Rico (Photo, Jan -,,**3) Some sampling sites with dates are shown with arrows The two sets of lateral moraines with di#erent materials can be clearly recognized The lower (younger) one looks young and soft; however, it is weakly indurated, implying its antiquity (crest is indicated with a dotted line) Fig 0 Another vegetation (grass) trimline (indicated with dotted red line) located below the prominent vegetation trimline, on the right valley side of Glaciar Perito Moreno, about 0 km up from the snout (Photo, Dec,0,,**1)

4 4 Bulletin of Glaciological Research On the valley slope of Glaciar Perito Moreno, trees (DHB, up to 2* cm) are still standing among there is one distinctive trimline located only several many fallen trees of a similar or larger size (Fig 1) tens of meters above the present glacier surface (Fig Four samples were taken in,**1 from dead yet still ) Another, younger lateral moraine can be clearly standing trees with DBH 2* cm Three samples (# +, recognized on the ground that is mostly composed of #- and #: sample numbers correspond to those in sand/silt/clay, rather than gravel/boulder of the Table + ) out of the four yielded an identical calibrated older lateral moraine which produced the trimline age, Cal AD +0/* (Table + ), while one sample (#,) (Fig /) The wood above the trimline is very similar yielded an anomalous age [later sampled again (# +/ ), to that of Brazo Rico About 0 km up from the termi- with Cal AD +00* ] The three identical ages suggest nus, another trimline, although sporadic, can be dis- that these trees were killed by the same event, that is, cerned, which is marked with grasses at ca,* m be- water submersion due to high water caused by damlow the distinctive one (Fig 0) Thus, there are two ming of advancing Glaciar Perito Moreno Later, in trimlines On the right valley slope near the lake February,*+*, two more samples were taken from one shore where the glacier flows into the lake, we can tree on this fan delta: one (# +, ) from the core of the recognize two types of tills with the di# erent degree tree and the other (# +-) from the surface Both of weathering or freshness These two trimlines, two yielded the same age, Cal AD +0/* A tree (# 2) on the sets of lateral moraines in general, and the two types lake shore covered with till near the glacier, which of tills indicate two recent advances was killed by water submersion, is Cal AD +02* (see Fig -) Radiocarbon Dating In order to check these ages, five samples were taken from the northern shore of Brazo Rico in December + Brazo Rico Shore,*+* Two samples were collected from dead The first sampling was carried out on a fan delta trees at Bajo de las Sombras (see Fig,): the sample below the vegetation trimline, where many large dead # +3 (DBH /* cm) with Cal AD +0/* is about / m higher Table + Radiocarbon measurements

5 Aniya et al than the present water surface, while the sample #,* (DBHῌ2* cm) with Cal AD +0* is +0 m higher than the sample #+3 A tree located higher yielded an age +* years older than that located lower, when both were killed by the rising water: however the di#erence is well within the error margin Three samples were collected from the Bahía Catalana and its saddle area, a longitudinal shallow valley leading to Canal de los Témpanos and separating Península Magallanes from the main land (Fig 2) The sample #,- (Cal AD +03*) is a large tree stump (DBH ῌ0* cm) located below the trimline at the Bahía Catalana, where numerous small dead trees that were killed during the +3/ῌ/0 damming are still standing The sample #,+ (Cal AD +0-*) was taken from a standing tree (DBH ῌ,/ cm) between bogs in the Bahía Catalana saddle, while the sample #,, (Cal AD +0/*) was taken from a fallen tree (DBH ῌ2* cm) at the highest point of the Bahía Catalana saddle From these ages, it appears reasonable to conclude that water became high ca AD +0/* for the first time in several hundreds of years during which a mature wood had developed, thereby killing large trees by water submersion Fig 1 Sampled standing trees on a fan delta below the vegetation trimline (Photo, Dec,/,,**1) Samples #, and #+/ were taken from the similar part of the same tree Samples #+, and #+- were taken from the same tree, but #+, from the core while #+- from the surface Ages are also indicated Fig 3 An example of sample (#3, AD +02*) and sampling site (Photo, Dec -+,,**2) The pond was formed by a lateral moraine that dammed a stream from the hillside Some trees are still standing in water On the left side, there is a younger moraine 5, Trimlines of Glaciar Perito Moreno Subsequently, based on the,**1 finding, many more samples were collected in December,**2 and February,*+* to determine the age of the trimline on the right bank of the glacier from those associated with the glacier advance They are three types (I) Trees uprooted (in situ) by lateral moraines formed by an advancing glacier, yielded Cal AD +0/* (sample #1), AD +1+* (#++) and AD +02* (#+) The tree stump of the sample #+ was originally sampled in +33*, from which an age of 2,*ῌ3* yr BP was obtained (NU-//, Aniya and Sato, +33/: Cal AD +,-*ῌ1*) We have no idea why there is a wide di#erence of more than ** Fig 2 Map showing the Bahía Catalana saddle area and sampling points with dates and sampling number in parentheses (map taken from +: +**,*** topographic map Glaciar Perito Moreno, published by Argentinean IGM in +323) Contours in meters The lake level, +2/ m, is given by an Argentinean company for water resources, EVARSA PM: Península Magallanes Sample #,, is located at the highest point of the saddle area (elev ῌ,,1 m) The wide red line is the road

6 6 Bulletin of Glaciological Research years between these two dating results, which exceeds even a range of, s In addition, conventional radiocarbon ages of +*, yr BP (#0) and +,1 yr BP (#+0) were obtained (II) Water-submerged tree in a pond that was formed by damming of a stream from the hillslope by newly formed lateral moraine, yielded Cal AD +02* (#3, Figs 3 & /) (III) Organic matter deposited and wood piece embedded in ponds that were formed by younger lateral moraines, yielded conventional radiocarbon ages of ++* yr BP (#+*) and +++ yr BP (#/, Figs +* & /), respectively Two wood pieces were collected from scattered tree litters on a lateral moraine right next to the glacier surface, about / km up from the terminus, which were brought to the surface and deposited by Fig +* Another example of sample (#/, +++ yr BP) and sampling site (Photo, Dec -+,,**2), an organic matter collected from a sediment-filled flat on the younger moraine thrusting from the glacier bed Because the tree litters here are very extensive, they were probably killed en masse by the advancing glacier and subsequently incorporated into the glacier body and trans ported sub/en-glacially to the present site before emerging onto the surface by thrusting Their ages are Cal AD +00* (#+1) and Cal AD +/* (#+2) / Discussion and Conclusions We have obtained two general ages for the trimlines and lateral moraines of Glaciar Perito Moreno (Fig ++ and Table +), Cal AD +0/*ῌ+1+* and +*,ῌ+,1 yr BP (probably equivalent to AD +2,-ῌ+22) From many of the samples taken on the lake shore we obtained the age of Cal AD +0/*, which is the same as the older age of the glacier trimlines Since killing of trees by water submersion is rather uniform in timing while uprooting of trees by lateral moraine formation occurs at di#erent times with unknown time lags, it appears reasonable to take Cal AD +0/* as the time of a LIA advance of the glacier Since we have two trimlines, two sets of lateral moraines, and two types of tills along the glacier, the two ages we obtained are congruent with the field evidences At the neighboring Glaciar Ameghino, Nichols and Miller (+3/+) first identified a LIA advance from the tree ring analysis at AD +21*ῌ2* Then, Aniya (+330) identified two rows of terminal moraines that are damming a proglacial lake, Laguna Ameghino and dated the older one to be -,*ῌ2* y BP (NU-0/3), concluding that an earlier LIA occurred around AD +0**ῌ Fig ++ Location of +C samplings at and around Glaciar Perito Moreno, with ages (conventional radiocarbon age indicated with y BP) Circles indicate samples taken in Dec,**1, triangles (red) those in Dec,**2, squares those in Feb,*+* and diamonds those in Dec,*+* (Satellite image, ALOS PRISM, March,2,,**2, courtesy of JAXA) The number in bracket after the age corresponds to that in Table +

7 Aniya et al 7 +1** This age was calibrated using Calib 0 * (Stuiver on the shores of Brazo Rico? We could interpret that and Reimer, +33- : http: //calibqubacuk/calib/calib the bog from which the sample #,+ was taken was cgi); thereby, Cal AD +0* was obtained from the cali- formed during the LIA, although we do not know bration curve This age agrees very well with the how; but the sample #,, was taken from the highest older age obtained for Glaciar Perito Moreno in this place, which could not have become a pond/bog If study The younger age, ca AD +2,* +2/* at Glaciar we can identify the cause of their death, a new inter- Perito Moreno is a little earlier than that at Glaciar pretation might emerge for the environment of Brazo Ameghino; however, if we consider the current di# er- Rico and the surrounding area during the +1th cenent behavior of each glacier, this amount of the time tury, and nature of the LIA advance of Glaciar Perito lag is quite plausible Moreno The sample #,- taken below the vegetation Glaciar Frías, which is located immediately south trimline at the Bahía Catalana yielded a Cal AD +03*, of Glaciar Perito Moreno (see Fig + ), has three rows of which is later than those located at higher grounds recent terminal moraines within + km of the ice front (#,+ and,,) or those located at Bajo de las Sombras (Mercer, +302 ) From the ages of trees given by Mercer (# +3 and,*), but the di# erence of * 0* years is within ( +302 ), Masiokas et al (,**3) estimated the formation the error margin of these three moraines as the mid-+3 th, early +3th and We conclude that Glaciar Perito Moreno made mid-+1 th centuries Of these, the early +3 th and the two LIA advances, at ca AD +0/* and AD +2,* /*, and mid-+1th century advances coincide with those at the environment of the Peninsula Magallanes and the Perito Moreno Bahía Catalana saddle area was probably much more The dates we obtained at the Bahía Catalana sad- complex than previously thought dle raise some interesting, but very enigmatic issues about the nature of environment during the LIA Acknowledgments Mercer ( +302) asserted that Glaciar Perito Moreno could not have been much larger than today, at least The comments made by an anonymous reviewer during the last *** years, based on the age -2-* ++/ are gratefully acknowledged This research was funded yr BP of the basal peat in a bog on the Bahía Catalana by the Japanese Ministry of Education, Science, saddle Since the basal peat has not been disturbed, Sports and Culture, Grant-in-Aid for Scientific Rehe concluded that this area has not been occupied as search (A) (Project No +2,/+**,, PI: M Aniya) and (B) spillway The bog from which Mercer ( +302 ) recov- (No,,*+**-, PI: M Aniya) Dr Shun Tsutaki, then a ered the peat sample has been drying up since then doctoral student at the Institute of Low Temperature and has now divided into two, and the sample #,+ Science, Hokkaido University, Japan, assisted in col- (DBH,/ cm, see Fig 2 ) is one of many dead trees still lecting samples in,**2 Hielo y Aventura S A kindstanding between these separated bogs, yielding a Cal ly o# ered the logistic support during the field activ- AD +0-* The sample #,, with a Cal AD +0/* is a ity at Glaciar Perito Moreno The authors are also fallen large tree (DBH 2* cm) at the highest point of very grateful to Paula Pera and Flavio Renzacchi for the Bahía Catalana saddle These two dates indicate measuring the height di# erences between Canal de that they were killed at the same time as those on the los Témpanos, the saddle and Bahía Catalana northern and southern shores of Brazo Rico Therefore, it is probable that the cause of death of those References trees located at the saddle was the water submersion Due to the topography of the saddle area, the water submersion could only have been possible if the water of Brazo Rico spilled through to Canal de los Témpanos Aniya, M ( +33/ ): Holocene glacial chronology in Patagonia: Tyndall and Upsala Glaciers Arct Alp Res,,1, -++ -,, Aniya, M ( +330): Holocene variations of Ameghino Glacier, when the water level was high due to ice dam- Southern Patagonia The Holocene, 0,,1,/, Aniya, M and Naruse, R ( +333): Late-Holocene glacial advances at Glaciar Soler, Hielo Patagónico Norte, South ming by advancing Glaciar Perito Moreno We checked the elevation figures of the area America Trans Japanese Geomorph Union,,*, given by Mercer ( +302 ), and the height di# erence from Aniya, M and Sato, H ( +33/ ): Holocene glacier variations at Tyndall Glacier area, southern Patagonia Bull Glacier the mean lake level to the saddle area of, m was Res, +-, 31 +*3 confirmed by the recent measurements The water Aniya, M and Shibata, Y (,**+): The Holocene glacial chronology level of a dammed Brazo Rico could not have risen of Río Soler valley, Hielo Patagónico Norte, Chile In Aniya, M and Naruse, R (eds), Glaciological and Geomorphological Studies in Patagonia, +332 and +333, area during the LIA, because a) the vegetation trim- Aniya, M and Skvarca, P ( +33, ): Characteristics and varia- more than, m in order to spill through the saddle line along the glacier margin is not that high, and b), if tions of Upsala and Moreno glaciers, southern Patagonia the water level had risen more than -+ m the water Bull Glacier Res, +*, -3 /- Aniya, M, Sato, H, Naruse, R, Skvarca, P, and Casassa, G would have spilled to Lago Argentino over the other ( +330): Remote sensing application to inventorying glaciers in a large, remote area - Southern Patagonia Ice- (east) end (Ra# o et al, +3/-) Then, why the trees on the saddle area were killed at the same time as those field Photogramm Eng Remote Sensing, 0,,

8 8 Bulletin of Glaciological Research Aniya, M, Barcaza, G and Iwasaki, S (,**1): Recent glacier Naruse, R, Skvarca, P and Kobayashi, S (,**+): Measureadvances at Glaciar Exploradores, Hielo Patagónico ments of surface height and flow velocity at the calving Norte, Chile Bull Glaciol Res,,, 3 /1 terminus of Perito Moreno Glacier, southern Patagonia, Ciappa A, Pietranera, L and Battazza, F (,*+*): Perito Mo- in December +333 In Aniya, M and Naruse, R (eds), reno Glacier (Argentina) flow estimation by COSMO SkyMed sequence of high-resolution SAR-X imagery Glaciological and Geomorphological Studies in Patagonia +332 and +333, ++ + Remote Sensing of Environ, ++ ( 3 ),,*22,*30 Nichols, R L and Miller, M M ( +3/+ ): Glacial geology of Harrison, S and Winchester, V (,***): Nineteenth and twen- Ameghino valley, Lago Argentino, Patagonia Geogr tieth-century glacier fluctuation and climatic implica- Rev, +,,1,3 tions in the Arco and Colonia Valleys, Hielo Patagonico Nichols, R L and Miller, M M ( +3/, ): The Moreno Glacier, Norte, Chile Arct Antarc Alp Res, -,, // 0- Lago Argentino, Patagonia: advancing glaciers and near- Harrison, S Winchester, V and Glasser, N (,**1): The timing by simultaneously retreating glaciers J Glaciol,,, and nature of recession of outlet glaciers of Hielo Pata- + 0 gónico Norte, Chile, from their Neoglacial IV (Little Ice Ra# o, J M, Colqui, B S and Madejski, M E ( +3/-): Glaciar Age) maximum positions Global and Planetary Changes, Moreno Dirección General del Servicio Meteorológico /3, Nacional, Buenos Aires, Serie Hidrometeorológica Publi- Heim, A ( +30 ): Informe sobre un estudio glaciológico en el cación, No 3,,3- -+ Parque Nacional Los Glaciares Administracíon General Reichert, F ( +3+1): Vorläufiger Bericht über das Ergebnis der de Parques Nacionales, Buenos Aires, +* p Expedition nach dem sogennant Patagonischen Inland- Liss, Von C C ( +31* ): Der Morenogletscher in der Pata- eis und dem Bismarckgletscher Zeitschrift für Gletscherkunde, gonischen Kordillere: sein ungewöhnliches verhalten +*,,,/,-* seit +233 und der eisdamm durchbruch des jahres +300 Rivera, A, Benham, T, Casassa, G, Bamber, J and Dowdeswell, Zeitschrift für Gletscherkunde and Glazialgeologie, VI ( + J (,**1): Ice elevation and areal changes of glaciers from,), * the Northern Patagonia Icefield, Chile Global and Planetary Marden, C J and Clapperton, C M ( +33/ ): Fluctuations of the Change, /3, +,0 +-1 southern Patagonia Icefield during the last glaciation Rott, H, Stuefer, M, Siegel, A, Skvarca, P and Eckstaller, A and the Holocene J Quat Sci, +*, +31,+* ( +332): Mass fluxes and dynamics of Moreno Glacier, Sou Masiokas, M H, Rivera, A, Espizua, L E, Villalba, R, Delgado, thern Patagonia Icefield Geophys Res Lett,,/ ( 3 ), +*1 S and Aravena, J C (,**3): Glacier fluctuations in extra ++* tropical South America during the past +*** years Palaeogeography, Skvarca, P and Naruse, R ( +331): Dynamic behavior of Gla- Palaeoclimatology, Palaeoecology,,2+,,,,02 ciar Perito Moreno, southern Patagonia Ann Glaciol,,, Mercer, J H ( +30, ): Glacier variations in the Andes Glaciol,02,1+ Note, +,, 3-+ Stuefer, M, Rott, H and Skvarca, P (,**1): Glaciar Perito Mercer, J H ( +30/ ): Glacier variations in Southern Patagonia Moreno, Patagonia: Climate sensitivities and glacier char- Geogr Rev, //, -3* +- acteristics preceding the,**-/* and,**//*0 damming Mercer, J H ( +302 ): Variations of some Patagonian glaciers events J Glaciol, /- ( +2* ), - +0 since the Late-Glacial Am J Sci,,00, 3+ +*3 + Stuiver, M and Reimer, P J ( +33-): Extended C database Michel, R and Rignot, E ( +333): Flow of Glaciar Moreno, and revised CALIB radiocarbon calibration program Radiocarbon, Argentina, from repeat-pass Shuttle Imaging Radar images: -/,,+/,-* comparison of the phase correlation method with Takeuchi, Y, Naruse, R and Skvarca, P ( +330): Annual airradar interferometry J Glaciol, / ( +3), 3- +** temperature measurement and ablation estimate at Mo- Naruse, R, Skvarca, P, Kadota, T and Koizumi, K ( +33, ): reno Glacier, Patagonia Bull Glacier Res, +,,-,2 Flow of Upsala and Moreno glaciers, southern Patago- Telford, R J, Heegaard, E and Birks, H J B (,**): The nia Bull Glacier Res, +*, // 0, intercept is a poor estimate of a calibrated radiocarbon Naruse, R, Skvarca, P, Satow, K, Takeuchi, Y and Nishida, age The Holocene, +,,30,32 K ( +33/ ): Thickness change and short-term flow varia- Warren, C R ( +33 ): Freshwater calving and anomalous glacier tion of Moreno Glacier, Patagonia Bull Glacier Res, +-, oscillations: recent behaviour of Moreno and Ame-,+,2 ghino glaciers, Patagonia The Holocene,,,,,3