Numerical Reconstruction of Three Holocene Glacial Events in Qiangyong Valley, Southern Tibetan Plateau and Their Implication for Holocene Climate Changes

The dating of well-preserved Holocene moraines in the Qiangyong Valley, southern Tibetan Plateau (TP), offers great potential for reconstructing Holocene glacier extents and examining climate changes in the region. Guided by Holocene moraine features, this study used Geographic Information System (GIS) model tools to reconstruct paleo-glacier surfaces and glacier equilibrium line altitude (ELA) depressions for three Holocene glacial stages in the valley. The GIS-based models showed that the Qiangyong Valley contained ice volumes of 8.1 × 108, 6.2 × 108, and 4.6 × 108 m3 during the early Holocene, Neoglacial, and Little Ice Age (LIA) glacial stages, and that the ELA was decreased by ~230 ± 25, ~210 ± 25, and ~165 ± 25 m, respectively, compared to modern conditions. Furthermore, the summer temperatures were estimated to be 1.56–1.79, 1.37–1.64, and 1.29–1.32 °C cooler than present to support the three Holocene glacier extents, based on the evidence that the respective precipitation increased by 20–98, 13–109, and 0.9–11 mm relative to the present, which were derived from the lacustrine pollen data for the southern TP. By comparison, this study found that the amplitudes of the ELA-based summer temperature depressions were much larger than the pollen-based counterparts for the three glacial stages, although the two proxies both showed increasing trends in the reconstructed summer temperatures.

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Climate-induced treeline mortality during the termination of the Little Ice Age in the Greater Yellowstone Ecoregion, USA

The Holocene ◽

10.1177/09596836211011656 ◽

2021 ◽

pp. 095968362110116

Author(s):

Maegen L Rochner ◽

Karen J Heeter ◽

Grant L Harley ◽

Matthew F Bekker ◽

Sally P Horn

Keyword(s):

Climate Change ◽

Tree Ring ◽

Little Ice Age ◽

Climate Changes ◽

Frost Damage ◽

Ice Age ◽

Spatial And Temporal Variability ◽

Whitebark Pine ◽

Engelmann Spruce ◽

Greater Yellowstone

Paleoclimate reconstructions for the western US show spatial variability in the timing, duration, and magnitude of climate changes within the Medieval Climate Anomaly (MCA, ca. 900–1350 CE) and Little Ice Age (LIA, ca. 1350–1850 CE), indicating that additional data are needed to more completely characterize late-Holocene climate change in the region. Here, we use dendrochronology to investigate how climate changes during the MCA and LIA affected a treeline, whitebark pine ( Pinus albicaulis Engelm.) ecosystem in the Greater Yellowstone Ecoregion (GYE). We present two new millennial-length tree-ring chronologies and multiple lines of tree-ring evidence from living and remnant whitebark pine and Engelmann spruce ( Picea engelmannii Parry ex. Engelm.) trees, including patterns of establishment and mortality; changes in tree growth; frost rings; and blue-intensity-based, reconstructed summer temperatures, to highlight the terminus of the LIA as one of the coldest periods of the last millennium for the GYE. Patterns of tree establishment and mortality indicate conditions favorable to recruitment during the latter half of the MCA and climate-induced mortality of trees during the middle-to-late LIA. These patterns correspond with decreased growth, frost damage, and reconstructed cooler temperature anomalies for the 1800–1850 CE period. Results provide important insight into how past climate change affected important GYE ecosystems and highlight the value of using multiple lines of proxy evidence, along with climate reconstructions of high spatial resolution, to better describe spatial and temporal variability in MCA and LIA climate and the ecological influence of climate change.

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Glacier equilibrium line altitude variations during the “Little Ice Age” in the Mediterranean Andes (30◦–37◦ S)

10.5194/cp-2019-37 ◽

2019 ◽

Author(s):

Álvaro González-Reyes ◽

Claudio Bravo ◽

Mathias Vuille ◽

Martin Jacques-Coper ◽

Maisa Rojas ◽

...

Keyword(s):

Little Ice Age ◽

Pearson Correlation ◽

Temporal Changes ◽

Global Climate Models ◽

Ice Age ◽

Equilibrium Line ◽

Equilibrium Line Altitude ◽

Mountainous Regions ◽

The Mean ◽

The Mediterranean

Abstract. The "Little Ice Age" (LIA; 1500–1850 Common Era (CE)), has long been recognized as the last period when mountain glaciers in many regions of the Northern Hemisphere (NH) recorded extensive growth intervals in terms of their ice mass and frontal position. The knowledge about this relevant paleoclimatic interval is vast in mountainous regions such as the Alps and Rocky Mountains in North America. However, in extra-tropical Andean sub-regions such as the Mediterranean Andes of Chile and Argentina (MA; 30º–37º S), the LIA has been poorly documented. Paradoxically, the few climate reconstructions performed in the MA based on lake sediments and tree rings do not show clear evidence of a LIA climate anomaly as observed in the NH. In addition, recent studies have demonstrated temporal differences between mean air temperature variations across the last millennium between both hemispheres. This motivates our hypothesis that the LIA period was not associated with a significant climate perturbation in the MA region. Considering this background, we performed an experiment using daily climatic variables from three Global Climate Models (GCMs) to force a novel glaciological model. In this way, we simulated temporal variations of the glacier equilibrium-line altitude (ELA) to evaluate the glacier response during the period 1500–1848 CE. Overall, each GCM shows temporal changes in annual ELA, with anomalously low elevations during 1640–1670 and 1800–1848 CE. An interval with high ELA values was identified during 1550–1575 CE. The spectral properties of the mean annual ELA in each GCM present significant periodicities between 2–7 years, and also significant decadal to multi-decadal signals. In addition, significant and coherent cycles at interannual to multi-decadal scales were detected between modeled mean annual ELAs and the first EOF1 extracted from Sea Surface Temperature (SST) within the El Niño 3.4 of each GCM. Finally, significant Pearson correlation coefficients were obtained between the mean annual ELA and Pacific SST on interannual to multi-decadal timescales. According to our findings, we propose that Pacific SST variability was the main modulator of temporal changes of the ELA in the MA region of South America during 1500–1848 CE.

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Recent, rapid and profound changes to glacier morphology and dynamics, Juneau Icefield, Alaska

10.5194/egusphere-egu21-1539 ◽

2021 ◽

Author(s):

Bethan Davies ◽

Jacob Bendle ◽

Robert McNabb ◽

Jonathan Carrivick ◽

Christopher McNeil ◽

...

Keyword(s):

Little Ice Age ◽

Ice Age ◽

Aerial Photographs ◽

Equilibrium Line Altitude ◽

Regional Warming ◽

Geomorphological Mapping ◽

Glacier Recession ◽

Digital Elevation ◽

High Resolution Satellite Imagery ◽

Global Sea Level

The Alaskan region (comprising glaciers in Alaska, British Columbia and Yukon) contains the third largest ice volume outside of the Greenland and Antarctic ice sheets, and contributes more to global sea level rise than any other glacierised region defined by the Randolph Glacier Inventory. However, ice loss in this area is not linear, but in part controlled by glacier hypsometry as valley and outlet glaciers are at risk of becoming detached from their accumulation areas during thinning. Plateau icefields, such as Juneau Icefield in Alaska, are very sensitive to changes in Equilibrium Line Altitude (ELA) as this can result in rapidly shrinking accumulation areas. Here, we present detailed geomorphological mapping around Juneau Icefield and use this data to reconstruct the icefield during the &#8220;Little Ice Age&#8221;. We use topographic maps, archival aerial photographs, high-resolution satellite imagery and digital elevation models to map glacier lake and glacier area and volume change from the Little Ice Age to the present day (1770, 1948, 1979, 1990, 2005, 2015 and 2019 AD). Structural glaciological mapping (1979 and 2019) highlights structural and topographic controls on non-linear glacier recession.&#160; Our data shows pronounced glacier thinning and recession in response to widespread detachment of outlet glaciers from their plateau accumulation areas. Glacier detachments became common after 2005, and occurred with increasing frequency since then. Total summed rates of area change increased eightfold from 1770-1948 (-6.14 km2 a-1) to 2015-2019 (-45.23 km2 a-1). Total rates of recession were consistent from 1770 to 1990 AD, and grew increasingly rapid after 2005, in line with regional warming.

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Glacier changes since the Little Ice Age maximum in the western Qilian Shan, northwest China, and consequences of glacier runoff for water supply

Journal of Glaciology ◽

10.3189/172756503781830926 ◽

2003 ◽

Vol 49 (164) ◽

pp. 117-124 ◽

Cited By ~ 120

Author(s):

Liu Shiyin ◽

Sun Wenxin ◽

Shen Yongping ◽

Li Gang

Keyword(s):

Little Ice Age ◽

Image Data ◽

Northwest China ◽

Ice Age ◽

Aerial Photographs ◽

Equilibrium Line Altitude ◽

North West ◽

Glacier Changes ◽

Glacier Runoff ◽

Topographical Maps

AbstractBased on aerial photographs, topographical maps and the Landsat-5 image data, we have analyzed fluctuations of glaciers in the western Qilian Shan, north-west China, from the Little Ice Age (LIA) to 1990. The areas and volumes of glaciers in the whole considered region decreased 15% and 18%, respectively, from the LIA maximum to 1956. This trend of glacier shrinkage continued and accelerated between 1956 and 1990. These latest decreases in area and volume were about 10% in 34 years. The recent shrinkage may be due either to a combination of higher temperatures and lower precipitation during the period 1956–66, or to continuous warming in the high glacierized mountains from 1956 to 1990. As a consequence, glacier runoff from ice wastage between 1956 and 1990 has increased river runoff by 6.2 km3 in the four river basins under consideration. Besides, the equilibrium-line altitude (ELA) rise estimated from the mean terminus retreat of small glaciers <1 km long is 46 m, which corresponds to a 0.3°C increase of mean temperatures in warm seasons from the LIA to the 1950s.

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Exposure dating of a pronounced glacier advance at the onset of the late-Holocene in the central Tyrolean Alps

The Holocene ◽

10.1177/0959683617690589 ◽

2017 ◽

Vol 27 (9) ◽

pp. 1350-1358 ◽

Cited By ~ 7

Author(s):

Andrew P Moran ◽

Susan Ivy Ochs ◽

Marcus Christl ◽

Hanns Kerschner

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Ice Age ◽

Similar Reaction ◽

Equilibrium Line Altitude ◽

Alpine Valley ◽

Modern Times ◽

Exposure Dating ◽

Glacier Advance ◽

Accumulation Area Ratio

A two-phased moraine system in the high Alpine valley of Lisenser Längental in the Stubai Alps of western Austria is located in an intermediate morphostratigraphic position constrained by ‘Egesen Stadial’ (Younger Dryas) moraines down valley and ‘Little Ice Age’ (‘LIA’) positions (modern times) up valley. The equilibrium line altitude (ELA) was about 50 m lower than during the ‘LIA’ when applying an accumulation area ratio of 0.67. Exposure dating of boulders with 10Be yields a mean age of 3750 ± 330 years for the more extensive outer moraine system and a single age of 3140 ± 280 years for the inner one. The ages correspond well to the ‘Loebben oscillation’, a sequence of multi-decadal to multi-centennial cooling phases at the onset of the late-Holocene, also recognized in other Alpine records. The climatic downturn was severe enough to cause small to medium-sized Alpine glaciers in the central Alps to advance significantly beyond their ‘LIA’ extent, but too short to trigger a similar reaction with large glaciers.

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Tree ring-dated fluctuation history of Midui glacier since the little ice age in the southeastern Tibetan plateau

Science China Earth Sciences ◽

10.1007/s11430-011-4338-3 ◽

2012 ◽

Vol 55 (4) ◽

pp. 521-529 ◽

Cited By ~ 24

Author(s):

Peng Xu ◽

HaiFeng Zhu ◽

XueMei Shao ◽

ZhiYong Yin

Keyword(s):

Tibetan Plateau ◽

Tree Ring ◽

Little Ice Age ◽

Ice Age ◽

Southeastern Tibetan Plateau ◽

History Of

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Extension of Glacier de Saint-Sorlin, French Alps, and equilibrium-line altitude during the Little Ice Age

Journal of Glaciology ◽

10.3189/172756502781831548 ◽

2002 ◽

Vol 48 (160) ◽

pp. 118-124 ◽

Cited By ~ 6

Author(s):

Louis Lliboutry

Keyword(s):

Little Ice Age ◽

Meteorological Data ◽

Vertical Gradient ◽

Winter Precipitation ◽

Ice Age ◽

Equilibrium Line ◽

Equilibrium Line Altitude ◽

French Alps ◽

The Mean ◽

Accumulation Area Ratio

AbstractGlacier de Saint-Sorlin, French Alps, left terminal moraines at 1.3, 2.9 and 3.7 km ahead of the present terminus. According to proxy data and to historical maps, these were formed in the 19th, 18th and 17th centuries, respectively. A plateau at 2700–2625 m was then surrounded by ice but never became an accumulation area. This fact shows that the equilibrium-line altitude (ELA) on the glacier never dropped below 2300 m. The following simple models apply sufficiently to yield reliable estimations of past ELA: (1) a uniform and constant vertical gradient of the mass balance, down to the terminus; and (2) a plane bed, with a slope of 8.5° and a uniform width. Then in a steady situation the accumulation–area ratio is 1/2. Compared to the mean for 1956–72, at the onset of the Little Ice Age the balances were higher by 3.75 m ice a−1, and the ELA was 400 m lower. Correlations between 1956–72 balances and meteorological data suggest that during the melting season the 0°C isotherm was about 800 m lower, while the winter precipitation at low altitudes did not change. These correlations may have been different in the past, but an equal lowering of the ELA and of the 0°C isotherm, as assumed by several authors, seems excluded.

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Little Ice Age glacier fluctuations reconstructed for the southeastern Tibetan Plateau using tree rings

Quaternary International ◽

10.1016/j.quaint.2012.04.011 ◽

2013 ◽

Vol 283 ◽

pp. 134-138 ◽

Cited By ~ 27

Author(s):

Haifeng Zhu ◽

Peng Xu ◽

Xuemei Shao ◽

Haijiang Luo

Keyword(s):

Tibetan Plateau ◽

Tree Rings ◽

Little Ice Age ◽

Ice Age ◽

Southeastern Tibetan Plateau ◽

Glacier Fluctuations

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Paleoclimatic reconstruction during the Little Ice Age in the Llanganuco basin, Cordillera Blanca (Peru)

10.5194/egusphere-egu2020-1726 ◽

2020 ◽

Author(s):

Joshua Er Addi Iparraguirre Ayala ◽

Jose Úbeda Palenque ◽

Ronald Fernando Concha Niño de Guzmán ◽

Ramón Pellitero Ondicol ◽

Francisco Javier De Marcos García-Blanco ◽

...

Keyword(s):

3D Reconstruction ◽

Air Temperature ◽

Little Ice Age ◽

Ice Age ◽

Lapse Rate ◽

Ratio Method ◽

Equilibrium Line Altitude ◽

Paleoclimatic Reconstruction ◽

High Resolution Satellite Images ◽

The Impact

The Equilibrium Line Altitude (ELA, m) is a good indicator for the impact of climate change on tropical glaciers , because it varies in time and space depending on changes in temperature and/or precipitation.The estimation of the ELA and paleoELA using the Area x Altitude Balance Ratio method (AABR; Osmaston, 2005) requires knowing the surface and hypsometry of glaciers or paleoglaciers (Benn et al. 2005) and the Balance Ratio (BR) correct (Rea, 2009).In the Llanganuco basin (~ 9&#176;3&#180;S; 77&#176;37&#180;W) there are very well preserved moraines near the current glaciers front. These deposits provide information to reconstruct the extent of paleoglaciers since the Little Ice Age (LIA) and deduce some paleo-climatic variables.The goal of this work has been to reconstruct the paleotemperature (&#176;C) during LIA, deduced from the difference between ELA AABR2016 and paleoELA AABRLIA.The paleoclimatic reconstruction was carried out in 6 phases: Phase 1) Development of a detailed geomorphological map (scale 1/10,000), in order to&#160; identify glacial landforms (advance moraines and polished rocks) which, due to their geomorphological context, can be considered of LIA, so palaeoglaciers can be delimited. Current glacial extension was done using dry season, high resolution satellite images. Phase 2) Glacial bedrock Reconstruction from glacier surface following the GLABTOP methodology (Linsbauer et al 2009). Phase 3) 3D reconstruction of paleoglacial surface using GLARE tool, based on bed topography and flow lines for each defined paleoglacial (Pellitero et al., 2016). As perfect plasticity model does not reflect the tension generated by the side walls of the valley, form factors were calculated based on the glacier thickness, lateral moraines and the geometry of the valley following the equation proposed by Nye (1952), adjusting the thicknesses generated in the paleoglacial front. Phase 4) Calculation of BR in a reference glacier (Artesonraju; 8&#176; 56&#8217;S; 77&#186;38&#8217;W), near to the study area, using the product BR = b &#8226; z &#8226; s, where BR= Balance Ratio; b= mass balance measured in fieldwork 2004-2014 (m); z= average altitude (meters) and s= surface (m2) of each altitude band of the glacier (with intervals of 100 m altitude). A value BR = 2.3 was estimated. Phase 5) Automatic reconstruction of the ELA &#160;AABR2016 and paleoELA AABRLIA using ELA Calculation tool (Pellitero et al. 2015) after 3D reconstruction of the glacial and paleoglacial surface in phases 2 and 3. Phase 6) Estimation of paleotemperature during LIA by solving the equation of Porter et al. (1995): &#8710;T (&#176;C)= &#8710;ELA &#8226; ATLR, where &#8710;T= air temperature depression (&#186;C); &#8710;ELA = variation of ELA AABR 2016-LIA and ATLR = Air Temperature Lapse Rate, using the average global value of the Earth (0.0065 &#176;C/m), considered valid for tropics.The results obtained were: ELA AABR2016= 5260m, paleoELA AABRLIA= 5084m, and &#8710;T = 1.1 &#176;C. The reconstruction of air paleotemperature is consistent with different studies that have estimated values between 1&#8211;2 &#176;C colder than the present, with intense rainfall (Matthews & Briffa, 2005; Malone et al., 2015).

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