Article

Calving retreat and proglacial lake growth at Hooker Glacier, Southern Alps, New Zealand

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  • Ministry of Civil Defence and Emergency Management
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Abstract

Hooker Glacier in the central Southern Alps of New Zealand has undergone significant downwasting and recession (∼2.14km) during the last two centuries. High retreat rates (51ma-1 1986-2001, 43ma-1 2001-2011) have produced a large (1.22km2) proglacial lake. We present a retreat scenario for Hooker Glacier. A retreat scenario predicts that the glacier terminus will stabilise >3km up-valley of the current lake outlet after 2028 when ice velocity equals calving rate. © 2013 The Authors. New Zealand Geographer

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... The five lake-terminating glaciers shown in Fig. 4 have experienced substantial terminal zone thinning (shown here and in Bolch et al., 2011;Nuimura et al., 2012), flow acceleration (Fig. 4) and increased longitudinal strain (Table 1), and sustained or accelerating ice front retreat rates over the last 26 years (Fig. 6). We therefore suggest that the set of processes incorporated into the model of Benn et al. (2007) are in operation on some Himalayan lake-terminating glaciers, as has been inferred on laketerminating glaciers in other glacierised regions (Muto and Furaya, 2013;Robertson et al., 2013;Sakakibara and Sugiyama, 2014;Chernos et al., 2016). The variability in cumulative glacier front retreat and glacier front retreat rates we show in Fig. 6, and the broad range of mass balance estimates generated for lake-terminating glaciers by King et al. (2017), likely reflects the variable response of glaciers depending on their topographic setting (i.e. ...
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... Hooker Lake had a greater than predicted volume in 1995 and 2002, but not in 2009. Comparison of 5 glacier terminus position and bathymetric maps in Robertson et al. (2013) indicates that in 1995, the glacier terminus was retreating out of a deep basin. By 2002, the glacier had retreated to the position of a deep notch in the bed profile. ...
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Historical records, including maps, photographs, paintings and written accounts, are used to reconstruct the changing ice levels and terminal positions of the six main valley glaciers in Mt Cook National Park, New Zealand. The historical record, which began in 1862, is compared with the New Zealand climatic record for the same period. Patterns of glacial fluctuation are related to the general trends in climate. Between 1862 and 1888 there was locally important glacier recession. This was followed by a cooler period marked by glacier advance. A glacier stillstand is recorded during the first four decades of the present century and since 1940, a period of general temperature warming, the glaciers have all receded. Ice fronts have retreated up to 5 km from positions reached in 1862 and ice levels have dropped over 100 m.
Article
Melt rates of the dead ice in front of "Imja Glacier Lake' varied between 0.1 and 2.7 m/yr during the period 1989-1994. A maximum in excess of 5.0 m/yr occurred where the ice surface had been submerged by lake water before 1994. The lake level fell from 5022 m asl in 1984 to about 5017 m in 1989, and to about 5007 m in 1994. This decrease is atributed to melt of dead ice along the outflow; thus there is less danger of collapse of the lateral moraines. Instead, the rapid melting is expected to cause the lake to expand westward, that is towards the terminal moraine. Maximum dimensions by the winter of 1992, is due to melting of the glacier at the east (upper) end of the lake. Nevertheless, if the melt rate is sustained the western shoreline could migrate to the edge of the terminal moraine in little more than seven years. Immediate action to lower the lake level below the level of the spillway is needed. -from Authors
Article
Abstract The Tasman Glacier is the largest glacier in New Zealand. Although 20th century warming caused down-wastage, it remained at its Little Ice Age terminus until the late 20th century. Since then, rapid calving retreat (Ur) has occurred, allowing a large (5.96 × 106 m2) proglacial lake to form (maximum depth ∼240 m). From sequential satellite image analysis and echo sounding of Tasman Lake, we document (Ur) from 2000 to 2008. Ur varies temporally, with mean Ur of 54 m/a from 2000 to 2006 and a mean Ur of 144 m/a from 2007 to 2008. Consistent with global data sets, calving rate appears closely associated with lake depth at the calving terminus.
Article
Blocks of ice with the proportions of tabular icebergs have been observed melting in water of different temperatures and salinities. The sub-surface shape adopted by the blocks melting in water of the same salinity as sea-water was typically a ‘bath-tub’ one. The basal and mean-side melt rates were of a similar value. The melt rates obtained in the laboratory for icebergs in water of a low temperature match those inferred from population studies of Antarctic icebergs. The melt rate is proportional to the water temperature above the onset of freezing raised to the power 1.5 and melt rates at 18°C are likely to be greater than one metre per day.
Article
Upon initial flooding, the lowermost section of Unteraargletscher, about 800 m long, will float, drift away, and melt. A rough estimate of the heat balance shows that the energy input into the lake would be sufficient to melt this ice within 2-3 years, so that calving and melting will continue at a frontal ice cliff. The main effort of the study was aimed at forecasting this retreat. A pre-existing seismic survey was supplemented by new soundings by radar and seismic reflection, resulting in reliable cross-sections and information about the sub-bottom material. The forecast is based on the existing mass flux and an empirical calving rate relationship with water depth and predicts an equilibrium position of the terminus some 3-4 km further back than today, and a gain of water storage volume of 50 × 106 m3 after 10 years. -from Authors
Article
Moraine-dammed glacial lakes are becoming increasingly common in the Himalaya as a result of glacier mass loss, causing concern about glacier lake outburst flood risk. In addition to extant lakes, the potential exists for many more to form, as more glaciers ablate down to the level of potential moraine dams. In this paper, we document the recent rapid growth of, a moraine-dammed lake on Ngozumpa Glacier, Nepal. Using a combination of ground-based mapping and sonar surveys, aerial photographs (<1 m resolution), and ASTER imagery (15 m resolution), processes and rates of lake expansion have been determined. The lake first formed between 1984 and 1992 when collapse of an englacial conduit allowed water to accumulate at the level of a gap in the lateral moraine, similar to km from the glacier terminus. Lake growth was initially slow, but since 2001 it has undergone exponential growth at an average rate of 10%y(-1). In 2009, the lake area was 300,000 m(2), and its volume was at least 2.2 million m(3). Calving, subaqueous melting, and melting of subaerial ice faces all contribute to the expansion of the lake; but large-scale, full-height slab calving is now the dominant contributor to growth. Comparison with other lakes in the region indicate that lake growth will likely continue unchecked whilst the spillway remains at its current level and may attain a volume of hundreds of millions of cubic metres within the next few decades.
Article
Termini of valley glaciers in the central Southern Alps are undergoing a three-phase sequence of retreat that began in the 1950s. An initial phase of melting and slow downwasting under thickening supraglacial debris mantles is associated with stationary or slowly retreating termini. This is followed by a transitional phase of disruption of insulating debris mantles allowing the rapid growth of shallow thermokarst lakes, the shape and location of which vary according to glacier gradient and marginal topography. A third phase of rapid calving retreat of ice cliffs into deepening proglacial lakes develops from the transitional phase. At no stage are terminal responses simply related to climate. Present transitions to calving retreat are related to the morphology of glacier termini, particularly to large outwash heads. Landform evidence indicates that similar calving phases do not appear to have occurred since Late Pleistocene deglaciation, so that present changes to glacier termini are of great significance in the context of the whole Holocene. At millennial timescales, the melting-calving transition is effectively instantaneous and represents a sharp threshold heralding rapid deglaciation. The commencement of calving is imminent at the stationary terminus of Tasman Glacier which will soon retreat rapidly as a result.
Article
Several ice‐contact lakes have formed in conjunction with twentieth century glacier retreat in Mt Cook National Park. They occupy overdeepened glacial valleys and are dammed by terminal moraines and/or outwash heads. During the autumns of 1994 and 1995, the temperature and bathymetry of “Maud lake”, “Godley lake”, and Hooker Lake were surveyed. The near‐glacier vertical water temperature profiles exhibited greater temperature variation than those at the distal ends of the lakes. Thermal stratification existed in Hooker Lake, whereas both Maud and Godley lakes were thoroughly mixed. Water temperatures in the latter were consistently between 3 and 4.5°C, but most parts of Hooker Lake were cooler than 2°C, with a minimum recorded temperature of 0.2°C. These contrasts are important because melting of submerged parts of glacier termini is significant for ablation rates and for the dynamics of calving termini. All the lakes are steep sided and deep. Maud and Godley lakes approach 100 m in depth, whereas Hooker Lake has a maximum recorded depth of 136 m. Extensive flat floors in Maud and Godley lakes probably reflect rapid sediment accumulation following glacier retreat. Water depth at the termini of iceberg‐calving glaciers is known to correlate strongly with rates of iceberg production and hence the rate of glacier retreat. However, given the substantial water depths through which these glaciers (and also the neighbouring Tasman Glacier) have retreated, they appear to be more stable than comparable glaciers in other countries. The subaqueous geometry of all the glacier termini comprises a projecting ramp of glacier ice. All the lakes are being enlarged by glacier retreat except Maud lake, which has been reduced in size since 1995 by the advance of Maud and Grey Glaciers.
Article
An investigation of 127 glaciers of the New Zealand Southern Alps shows the losses that have occurred since the end of the Little Ice Age. On average they have shortened by 38% and lost 25% in area. The great variability within the measurements emphasises the need to consider response times and climate sensitivity when analysing glacier fluctuations. The upward shift of glacier mean elevation with this century of change is approximately equivalent to a temperature rise of 0.6°C. Extensive debris cover on many glaciers is significant in damping the climate signal, and proglacial lake formation may decouple a glacier from the climate signal.
Based on a review of observations on different types of calving glaciers, a simple calving model is proposed. Glaciers that exist in a sufficiently cold climate can form floating ice shelves and ice tongues that typically do not extend beyond confinements such as lateral fjord walls or mountains, and ice rises. If the local climate exceeds the thermal limit of ice shelf viability, as is the case for temperate glaciers, no floating tongue can be maintained and the position of the terminus is determined by the thickness in excess of flotation. If the snout is sufficiently thick, a stable terminus position at the mouth of the confining fjord - usually marked by a terminal shoal - can be maintained. Further advance is not possible because of increasing sea-floor depth and diverging flow resulting from lack of lateral constraints. If a mass balance deficiency causes the terminal region to thin, retreat is initiated with the calving front retreating to where the thickness is slightly in excess of flotation. In that case, the calving rate is determined by glacier speed and thickness change at the glacier snout. Advance or retreat of the calving front is not driven by changes in the calving rate, but by flow-induced changes in the geometry of the terminal region. This model is essentially different from prior suggestions in which some empirical relation - most commonly the water-depth model - is used to calculate calving, rate and the rate of retreat or advance of the terminus.
Article
Ablation of debris-mantled glaciers in Nepal has resulted in the formation of several potentially unstable moraine-dammed lakes, some of which constitute serious hazards. Ngozumpa Glacier, Khumbu Himal, has undergone significant downwasting in recent decades, and is believed to lie close to the threshold for moraine-dammed lake formation. The debris-mantled ablation area of the glacier is studded with numerous supraglacial lakes, the majority of which occupy closed basins with no perennial connections to the englacial drainage system ("perched lakes''). Perched lakes can undergo rapid growth by subaerial and water-line melting of exposed ice faces, and calving. Subaerial and subaqueous melting beneath thick(>1m) debris mantles is comparatively insignificant. Although lake expansion can contribute substantially to ablation of the glacier, perched lakes cannot continue to grow indefinitely, but are subject to rapid drainage once a connection is made to englacial conduits. The level of one of the lakes on the Ngozumpa, however, is controlled by the altitude of a spillway through the lateral moraine of the glacier. This lake underwent only limited growth in the period 1998-2000, but is likely to experience monotonic growth if glacier mass balance continues to be negative.
Article
Calving speeds and calving mechanisms in fresh water contrast with those in tidewater. We obtained calving speeds for six lake-calving glaciers in New Zealand's Southern Alps, and surveyed the depths and temperatures of their ice-contact lakes. The glaciers are temperate, grounded in shallow (≤20 m) water, and exhibit compressive flow at their termini. These data increase the global dataset of fresh-water calving statistics by 40%, bringing the total to 21glaciers. For this dataset, calving rates (uc) correlate positively with water depths (hw) (r2 = 0.83), the relationship being expressed by: uc = 17.4 + 2.3hw. This is an order of magnitude lower than values of uc at temperate tide-water glaciers. For a subset of 10 glaciers for which ice-proximal water temperature (tw) data are available, uc also correlates positively with tw, supporting a physical relation between calving and melting at and below the water-line. Fluctuations of New Zealand lake-calving glaciers in the period 1958-97 show that although the transition from non-calving to calving dramatically increases frontal retreat rates, the onset of calving does not isolate terminus change from climatic forcing. In terms of climatic sensitivity, lake-calving glaciers occupy an intermediate position between tidewater glaciers (least sensitive) and non-calving glaciers (most sensitive).
Article
Controls on glacier calving rates are receiving increased scientific interest. At fresh-water-calving glaciers, limnological factors might be more important than glaciological ones. Measurements of thermo-erosional notch development at the calving ice cliff of Tasman Glacier, New Zealand, suggest that the calving rates at this glacier are directly controlled by the rate of thermal undercutting. Notch formation rates typically vary between 10 and 30 cm d−1 (maximum rate 65 cm d−1) in summer, corresponding to an average calving rate of 34 m a−1. Notch formation is slower than waterline melt and is controlled by water temperatures and circulation, cliff geometry, debris supply and water-level fluctuations. The latter shift the position of undercutting, resetting the level of the notch formation process and thereby slowing it. The geometry of the notch and the debris supply determine the extent of influence of the lake on notch water temperatures and circulation. Hence, water temperatures in the lake are not necessarily indicative of the rate of notch formation. The prediction of rate of notch formation from far-field variables is hampered by the complex interaction of the influencing factors. The significance of thermal undercutting as a calving rate-controlling process decreases with increasing ice velocities, calving rates and surface gradients.
Article
Despite their relatively small total ice volume, mid-latitude valley glaciers are expected to make a significant contribution to global sea-level rise over the next century due to the sensitivity of their mass-balance systems to small changes in climate. Here we use a degree-day model to reconstruct the past century of mass-balance variation at 'Ka Roimata o Hine Hukatere' Franz Josef Glacier, New Zealand, and to predict how mass balance may change over the next century. Analysis of the relationship between temperature, precipitation and mass balance indicates that temperature is a stronger control than precipitation on the mass balance of Franz Josef Glacier. The glacier's mass balance, relative to its 1986 geometry, has decreased at a mean annual rate of 0.02 ma−1 w.e. between 1894 and 2005. We compare this reduction to observations of terminus advance and retreat, of which Franz Josef Glacier has the best record in the Southern Hemisphere. For the years 2000-05 the relative mass balance ranged from −0.75 to +1.50 ma−1 w.e., with 2000/01 the only year showing a negative mass balance. In a regionally downscaled Intergovernmental Panel on Climate Change mean warming scenario, the annual relative mass balance will continue to decrease at 0.02 ma−1 w.e. through the next century.
Article
Glaciar Nef, a 164 km2eastern outlet of Hielo Patagónico Norte (the northern Patagonia icefield), terminates in a proglacial lake that has formed in conjunction with 20th-century glacier retreat. The terminus is inferred to be transiently afloat. A hinge-calving mechanism is proposed in which buoyant forces impose a torque on the glacier tongue, resulting in the release of coherent sections of the glacier tongue as "tabular" ice-bergs. A simple model shows how torque and tensile stress reach a maximum at the up-glacier limit of the buoyant zone, and that glacier thinning causes this point to migrate up-glacier. Empirical evidence supporting this model includes elevated thermo-erosional notches ≤6.5 m above lake level, and the ubiquitous presence since 1975 of "tabular" ice- bergs with surface areas ≤0.3 km2. Flow speeds of 1.2−1.3 m d−1 were measured near the terminus in February 1998. Extrapolations from these short-term data yield a calvingrate of 785−835 m a−1 and a calvingflux of 232 × 106 m3 a−1 or 0.2 km3 a−1. The calculated mean water depth at the terminus is 190 m. This calvingrate is higher than at grounded temperate glaciers calving in fresh water, but is nevertheless almost an order of magnitude less than calvingrates at both grounded and floatingtidewater glaciers.
Article
The rates and processes of freshwater calving at Miage Glacier (Mont Blanc Massif, Italy) are described. Calving at Miage Glacier has occurred for two centuries on its right-lateral side, into a small ice-marginal lake (Miage Lake). Field surveys identified the main processes leading to iceberg production and quantified the calving losses over a summer season. Calving losses were compared (1) with the surface ablation of the debris-covered tongue, evaluated through a simple model based on measured ablation rates at different altitudes and debris cover thicknesses, and (2) with other inputs to the lake (stream inflow discharge) and with the lake volume. Results show that thermal undercutting by warmer surface water plays an important role in driving ice-cliff evolution. Thermal notches grow at ∼30–35m year−1 and cause a similar amount of cliff retreat. Calving contributes ∼2% of the estimated summer runoff from the debris-covered part of the ablation zone, but this is equivalent to ∼38% of the lake volume, and is of the same magnitude as the mean discharge from the inflow streams. These data indicate that calving of the ice cliff is one of the main water sources for maintaining the lake at the maximum summer volume, with the surface at the level of the subaerial outlet stream. A survey of Italian calving glaciers shows that calving is becoming more widespread, and that debris covers are present at all calving ice margins. The lake–ice interactions described in this study can, therefore, be considered to have wider representativeness. Copyright © 2006 John Wiley & Sons, Ltd.
Article
Mendenhall Glacier is a lake-calving glacier in southeastern Alaska, USA, that is experiencing substantial thinning and increasingly rapid recession. Long-term mass wastage linked to climatic trends is responsible for thinning of the lower glacier and leaving the terminus vulnerable to buoyancy-driven calving and accelerated retreat. Bedrock topography has played a major role in stabilizing the terminus between periods of rapid calving and retreat. Lake-terminating glaciers form a population distinct from both tidewater glaciers and polar ice tongues, with some similarities to both groups. Lacustrine termini experience fewer perturbations (e.g. tidal flexure, high subaqueous melt rates) and are therefore inherently more stable than tidewater termini. At Mendenhall, rapid thinning and simultaneous retreat into a deeper basin led to flotation conditions along approximately 50% of the calving front. This unstable terminus geometry lasted for approximately 2 years and culminated in large-scale calving and terminus collapse during summer 2004. Buoyancy-driven calving events and terminus break-up can result from small, rapidly applied perturbations in lake level.
Article
The interpretation of climate change based on the behavior of small cirque glaciers is not always straightforward or unique. In this study of Sperry Glacier, Glacier National Park, Montana, we model future change of the glacier under 11 different warming scenarios. The scenarios vary from no warming from present conditions to warming at a linear rate of 10 °C/century. We assume constant precipitation and only consider change invoked by warming. Our cellular automata model is based on simple rules that account for mass balance gradient, aspect, avalanching, and the flow of ice to redistribute mass. We constrain the model with glaciological data including georadar-measured ice depth, field-measured surface mass balance, and field-mapped ice surface topography. Under the most probable temperature increase based on downscaled OA-GCM output for the IPCC A1B scenario, we conservatively estimate the glacier persisting through at least 2080. By comparing glacier volume responses to different warming scenarios we elucidate a relationship between the magnitude of temperature change and the sensitivity of the glacier to small variations in the temperature increase. We find that the greater the magnitude of the temperature increase, the less sensitive the glacier area and volume become to slight differences in the warming rate. If we generalize this relationship to the region, we expect that a small change in climate will produce varying responses for glaciers throughout the region, whereas the glacier response to a large change in climate will likely be very similar over the entire region.
Article
Norway and New Zealand both experienced recent glacial advances, commencing in the early 1980s and ceasing around 2000, which were more extensive than any other since the end of the Little Ice Age. Common to both countries, the positive glacier balances are associated with an increase in the strength of westerly atmospheric circulation which brought increased precipitation. In Norway, the changes are also associated with lower ablation season temperatures. In New Zealand, where the positive balances were distributed uniformly throughout the Southern Alps, the period of increased mass balance was coincident with a change in the Interdecadal Pacific Oscillation and an associated increase in El Niño/Southern Oscillation events. In Norway, the positive balances occurred across a strong west-east gradient with no balance increases to the continental glaciers of Scandinavia. The Norwegian advances are linked to strongly positive North Atlantic Oscillation events which caused an overall increase of precipitation in the winter accumulation season and a general shift of maximum precipitation from autumn towards winter. These cases both show the influence of atmospheric circulation on maritime glaciers.
Article
The nature and rate of the transition from a thinning, melting ablation zone to a retreating, calving terminus is examined at the debris-mantled Tasman Glacier. The debris mantle has existed since the earliest glaciological observations were made in 1863, indicating that debris cover is the normal glaciological state regardless of historic mass-balance change. The relationship between debris thickness and ablation rate has been derived from short-term heat flow calculations. Extrapolation over time and space indicate that the thermal effect of the debris mantle has resulted in a post-1890 reduction in glacier surface gradient which, through positive feedback involving ablation rate, ice velocity and particle emergence paths, has caused upglacier spread of supraglacial debris and upstream migration of the locus of maximum ablation. This has lead to the preservation of a long ice tongue at low gradient while preventing terminus retreat from the outwash head, and has made the glacier vulnerable to calving. Since the late 1970s, thermokarst melting has formed an ice-contact proglacial lake in which water depths now exceed ca. 130 m against the ice front. Since 1994, evidence of extending and accelerating flow may indicate the imminent onset of rapid calving. Predicted retreat scenarios suggest a rapid retreat of at least 10 km will probably cause major (possibly catastrophic) rock and debris avalanches into the enlarging proglacial lake as debuttressing of mountainsides progresses.
Article
This paper presents data concerning recent (1990–2007) surface morphological and ice-dynamical changes on the Tasman Glacier, New Zealand. We use remote-sensing data to derive rates of lake growth, glacier velocities and rates of glacier surface lowering. Between 1990 and 2007, the glacier terminus receded ~ 3.5 km and a large ice-contact proglacial lake developed behind the outwash head. By 2007 the lake area was ~ 6 km2 and had replaced the majority of the lowermost 4 km of the glacier tongue. There is evidence that lake growth is proceeding at increasing rates — the lake area doubled between 2000 and 2007 alone. Measured horizontal glacier velocities decline from 150 m a− 1 in the upper glacier catchment to almost zero at the glacier terminus and there is a consequent down-glacier increase in surface debris cover. Surface debris mapping shows that a large catastrophic rockfall onto the glacier surface in 1991 is still evident as a series of arcuate debris ridges below the Hochstetter icefall. Calculated glacier surface lowering is most clearly pronounced around the terminal area of the glacier tongue, with down-wasting rates of 4.2 ± 1.4 m a− 1 in areas adjacent to the lateral moraine ridges outside of the current lake extent. Surface lowering rates of approximately 1.9 ± 1.4 m a− 1 are common in the upper areas of the glacier. Calculations of future lake expansion are dependent on accurate bathymetric and bed topography surveys, but published data indicate that a further 8–10 km of the glacier is susceptible to calving and further lake development in the future.
Article
Oblique aerial photography of 111 glaciers during the past 2 decades has recorded a reversal of the past century glacier-recession trend. Cirque glaciers show little response to the recent mass balance increase; mountain glaciers show visible advances. Some valley glaciers have advanced, some have thickened in the upper trunk, and the larger ones and those with proglacial lakes continue to recede. The shift to advance is driven by an average lowering of snowlines of 67 m, equivalent to a cooling of 0.47°C if other factors are held constant.
Article
After a long period of general retreat, the Franz Josef Glacier on the western flanks of the Southern Alps of New Zealand has undergone a major advance, beginning about 1982. Key climatic variables, atmospheric circulation patterns over the Southwest Pacific, and the Southern Oscillation Index (SOI), are compared for two 20-year periods that represent advance and retreat phases of the Franz Josef Glacier. The results show strong links between atmospheric circulation changes, climate variables and glacier behaviour. The retreat phase is characterised by slightly warmer temperatures and markedly lower precipitation in the ablation season, a high pressure anomaly over New Zealand, and a southward shift in the subtropical high pressure zone. In contrast, the advance phase is characterised by anomalous southwest airflow, especially during the ablation season, and higher precipitation. The high pressure anomaly is shifted westward by about 55° of longitude so as to lie south of Australia. The advance phase is also related to a higher frequency of El Niño events.
Article
I constructed a temperature history for different parts of the world from 169 glacier length records. Using a first-order theory of glacier dynamics, I related changes in glacier length to changes in temperature. The derived temperature histories are fully independent of proxy and instrumental data used in earlier reconstructions. Moderate global warming started in the middle of the 19th century. The reconstructed warming in the first half of the 20th century is 0.5 kelvin. This warming was notably coherent over the globe. The warming signals from glaciers at low and high elevations appear to be very similar.
Glacier response to climate change
  • J Salinger
  • Tjh Chinn
  • A Willsman
  • B Fitzharris
Salinger J, Chinn TJH, Willsman A, Fitzharris B (2008). Glacier response to climate change. Water & Atmosphere 16, 16-7.
Columbia Glacier during rapid retreat: interactions between glacier flow and iceberg calving dynamics
  • Mf Meier
Meier MF (1994). Columbia Glacier during rapid retreat: interactions between glacier flow and iceberg calving dynamics. In: Reeh N, ed. Workshop on the Calving Rate of West Greenland Glaciers in Response to Climate Change. Danish Polar Center Report, Copenhagen, p. 171.