Neoglaciation in the Southern Kenai Mountains, Alaska

A preliminary late-Holocene glacial chronology from the west flank of the southern Kenai Mountains, Alaska, is characterized by two major episodes of advance. Outlet glaciers of both the Harding Icefield and the Grewingk-Yalik ice complex were expanding across their present positions at 545 A.D. and again during the Little Ice Age, about 1500 A.D. The earliest of these Neoglacial advances is dated by radiocarbon ages from the outer rings of tree trunks rooted near the margins of Grewingk and Dinglestadt glaciers. Subsequently, ice margins retreated some distance behind their present positions allowing marked soil development before the last readvance through mature forest. Wood preserved in lateral moraines at Grewingk Glacier and from an uprooted stump at Tustemena Glacier date this later ice advance. Tree-ring ages, correlated with lichen diameters, suggest that this last advance was widespread and culminated in its Neoglacial maximum about 1800 A.D.. Since this time, glacier retreat has dominated in the area, punctuated by at least two pauses. Historical accounts and photographs document a mean rate of retreat of 27 m a−1 for the past century with partial control exerted by calving of ice margins into proglacial lakes.

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Temporal Change of Radiocarbon Reservoir Effect in Sugan Lake, Northwest China during the Late Holocene

Radiocarbon ◽

10.1017/s0033822200055909 ◽

2009 ◽

Vol 51 (2) ◽

pp. 529-535 ◽

Cited By ~ 36

Author(s):

Ai-feng Zhou ◽

Fa-hu Chen ◽

Zong-li Wang ◽

Mei-lin Yang ◽

Ming-rui Qiang ◽

...

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Temporal Change ◽

Northwest China ◽

Climatic Changes ◽

Lacustrine Sediment ◽

Ice Age ◽

Reservoir Effect ◽

The Past ◽

Reservoir Age

Many lacustrine chronology records suffer from radiocarbon reservoir effects. A continuous, accurate varve chronology, in conjunction with accelerator mass spectrometry (AMS) 14C dating, was used to determine the age of lacustrine sediment and to quantify the past 14C reservoir effect in Sugan Lake (China). Reservoir age varied from 4340 to 2590 yr due to 14C-depleted water in the late Holocene. However, during the Little Ice Age (LIA), 14C reservoir age was relatively stable. According to this study, 14C reservoir age in the late Holocene may be driven by hydrological and climatic changes of this period. Therefore, special caution should be paid to the correction of the 14C reservoir effect by a unique 14C reservoir age in paleoclimatic and paleolimnological study of northwest China.

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Little ice age advance and retreat of Glaciar Jorge Montt, Chilean Patagonia, recorded in maps, air photographs and dendrochronology

Climate of the Past Discussions ◽

10.5194/cpd-7-3131-2011 ◽

2011 ◽

Vol 7 (5) ◽

pp. 3131-3164 ◽

Cited By ~ 2

Author(s):

A. Rivera ◽

M. Koppes ◽

C. Bravo ◽

J. C. Aravena

Keyword(s):

Little Ice Age ◽

Dynamic Responses ◽

Ice Age ◽

Past Century ◽

Present Position ◽

Tidewater Glaciers ◽

The Past ◽

Chilean Patagonia ◽

Southern Patagonia ◽

Induced Changes

Abstract. Glaciar Jorge Montt (48°20' S/73°30' W), one of the main tidewater glaciers of the Southern Patagonian Icefield (SPI), has experienced the fastest frontal retreat observed in Patagonia during the past century, with a recession of 19.5 km between 1898 and 2011. This record retreat uncovered trees overridden during the Little Ice Age (LIA) advance of the glacier. Samples of these trees were dated using radiocarbon methods, yielding burial ages between 460 and 250 cal yr BP. The dendrochronology and maps indicate that Glaciar Jorge Montt was at its present position before the beginning of the LIA, in concert with several other glaciers in Southern Patagonia, and reached its maximum advance position between 1650 and 1750 AD. The post-LIA retreat is most likely triggered by climatically induced changes during the 20th century, however, Glaciar Jorge Montt has responded more dramatically than its neighbours. The retreat of Jorge Montt opened a new fjord 19.5 km long, and up to 391 m deep, with a varied bathymetry well correlated with glacier retreat rates, suggesting that dynamic responses of the glacier are at least partially connected to near buoyancy conditions at the ice front, resulting in high calving fluxes, accelerating thinning rates and rapid ice velocities.

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The changing extent of marine-terminating glaciers and ice caps in northeastern Svalbard since the ‘Little Ice Age’ from marine-geophysical records

The Holocene ◽

10.1177/0959683619887429 ◽

2019 ◽

Vol 30 (3) ◽

pp. 389-401 ◽

Cited By ~ 3

Author(s):

Julian A Dowdeswell ◽

Dag Ottesen ◽

Valerie K Bellec

Keyword(s):

Little Ice Age ◽

Ice Age ◽

Aerial Photographs ◽

Past Century ◽

Ice Caps ◽

The Past ◽

Covered Area ◽

Data Coverage ◽

Climatic Cooling ◽

Glacial Landforms

Climate warming in Svalbard since the end of the ‘Little Ice Age’ early in the 20th century has reduced glacier extent in the archipelago. Previous attempts to reconstruct ‘Little Ice Age’ glacier limits have encountered problems in specifying the area of tidewater glacier advances because it is difficult to estimate the past positions of their marine termini. Multibeam echo-sounding data are needed to map past glacier extent offshore, especially in open-marine settings where subaerial lateral moraines cannot be used due to the absence of fjord walls. We use the submarine glacial landform record to measure the recent limits of advance of over 30 marine-terminating northeastern Svalbard glaciers and ice caps. Our results demonstrate that previous work has underestimated the ice-covered area relative to today by about 40% for northeastern Svalbard (excluding southeast Austfonna) because marine-geophysical evidence in the form of submarine terminal moraines was not included. We show that the recent ice extent was 1753 km2 larger than today over our full area of multibeam data coverage; about 5% of the total modern ice cover of Svalbard. It has often been assumed that moraine ridges located within a few kilometres of modern ice fronts in Svalbard represent either a ‘Little Ice Age’ maximum or relate to surge activity over the past century or so. In the marine environment of northeastern Svalbard, this timing can often be confirmed by reference to early historical maps and aerial photographs. Assemblages of submarine glacial landforms inshore of recently deposited terminal moraines suggest whether a recent advance may be a result of surging or ‘Little Ice Age’ climatic cooling relative to today. However, older terminal moraines do exist in the archipelago, as shown by radiocarbon and 10Be dating of Holocene moraine ridges.

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Late-Holocene climate response and glacial fluctuations revealed by the sediment record of the monsoon-dominated Chorabari Lake, Central Himalaya

The Holocene ◽

10.1177/0959683620908654 ◽

2020 ◽

Vol 30 (7) ◽

pp. 953-965 ◽

Cited By ~ 1

Author(s):

Tanuj Shukla ◽

Manish Mehta ◽

DP Dobhal ◽

Archna Bohra ◽

Bhanu Pratap ◽

...

Keyword(s):

Late Holocene ◽

Climatic Variability ◽

Ice Age ◽

Lateral Moraine ◽

Central Himalaya ◽

Short Term ◽

The Past ◽

Glacial Chronology ◽

Monsoonal Precipitation ◽

The Himalaya

We studied a periglacial lake situated in the monsoon-dominated Central Himalaya where an interplay of monsoonal precipitation and glacial fluctuations during the late Holocene is well preserved. A major catastrophe occurred on 16–17 June 2013, with heavy rains causing rupturing of the moraine-dammed Chorabari Lake located in the Mandakini basin, Central Himalaya, and exposed 8-m-thick section of the lacustrine strata. We reconstructed the late-Holocene climatic variability in the region using multi-parametric approach including magnetic, mineralogical and chemical (XRF) properties of sediments, paired with grain size and optically simulated luminescence (OSL) dating. The OSL chronology suggests that the lake was formed by a lateral moraine during the deglaciation phase of Chorabari Glacier between 4.2 and 3.9 ka and thereafter the lake deposited about 8-m-thick sediment sequence in the past 2.3 ka. The climatic reconstruction of the lake broadly represents the late-Holocene glacial chronology of the Central Himalaya coupled with many short-term climatic perturbations recorded at a peri-glacial lake setting. The major climatic phases inferred from the study suggests (1) a cold period between 260 BCE and 270 CE, (2) warmer conditions between 900 and 1260 CE for glacial recession and (3) glacial conditions between ~1370 and 1720 CE when the glacier gained volume probably during the ‘Little Ice Age’ (LIA). We suggest a high glacial sensitivity to climatic variability in the monsoon-dominated region of the Himalaya.

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Little Ice Age advance and retreat of Glaciar Jorge Montt, Chilean Patagonia

Climate of the Past ◽

10.5194/cp-8-403-2012 ◽

2012 ◽

Vol 8 (2) ◽

pp. 403-414 ◽

Cited By ~ 28

Author(s):

A. Rivera ◽

M. Koppes ◽

C. Bravo ◽

J. C. Aravena

Keyword(s):

Little Ice Age ◽

Dynamic Responses ◽

Ice Age ◽

Past Century ◽

Present Position ◽

Tidewater Glaciers ◽

The Past ◽

Old Growth Forest ◽

Chilean Patagonia ◽

Induced Changes

Abstract. Glaciar Jorge Montt (48°20' S/73°30' W), one of the main tidewater glaciers of the Southern Patagonian Icefield (SPI), has experienced the greatest terminal retreat observed in Patagonia during the past century, with a recession of 19.5 km between 1898 and 2011. This retreat has revealed trees laying subglacially until 2003. These trees were dated using radiocarbon, yielding burial ages between 460 and 250 cal yrs BP. The presence of old growth forest during those dates indicates that Glaciar Jorge Montt was upvalley of its present position before the commonly recognized Little Ice Age (LIA) period in Patagonia. The post-LIA retreat was most likely triggered by climatically induced changes during the 20th century; however, Glaciar Jorge Montt has responded more dramatically than its neighbours. The retreat of Jorge Montt opened a 19.5 km long fjord since 1898, which reaches depths in excess of 390 m. The bathymetry is well correlated with glacier retreat rates, suggesting that dynamic responses of the glacier are at least partially connected to near buoyancy conditions at the ice front, resulting in high calving fluxes, accelerating thinning rates and rapid ice velocities.

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Multiproxy paleoecological evidence of Holocene climatic changes on the Boothia Peninsula, Canadian Arctic

Quaternary Research ◽

10.1016/j.yqres.2016.02.003 ◽

2016 ◽

Vol 85 (3) ◽

pp. 347-357 ◽

Cited By ~ 2

Author(s):

Marie-Claude Fortin ◽

Konrad Gajewski

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Canadian Arctic ◽

Ice Age ◽

The Arctic ◽

Biological Production ◽

The Past ◽

Air Temperatures ◽

Ecosystem Level ◽

Rate Of Cooling

A study of chironomid remains in the sediments of Lake JR01 on the Boothia Peninsula in the Central Canadian Arctic provides a high-resolution record of mean July air temperatures for the last 6.9 ka. Diatom and pollen studies have previously been published from this core. Peak Holocene temperatures occurred prior to 5.0 ka, a time when overall aquatic and terrestrial biological production was high. Chironomid-inferred summer air temperatures reached up to 7.5°C during this period. The region of Lake JR01 cooled over the mid- to late-Holocene, with high biological production between 6.1 and 5.4 ka. Biological production decreased again at ∼2 ka and the rate of cooling increased in the past 2 ka, with coolest temperatures occurring between 0.46 and 0.36 ka, coinciding with the Little Ice Age. Although biological production increased in the last 150 yr, the reconstructed temperatures do not indicate a warming during this time. During transitions, either warming or cooling, chironomid production increases, suggesting an ecosystem-level response to climate variability, seen at a number of lakes across the Arctic.

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Sensitivity of wetland hydrology to external climate forcing in central Florida

Quaternary Research ◽

10.1016/j.yqres.2015.09.003 ◽

2015 ◽

Vol 84 (3) ◽

pp. 287-300 ◽

Cited By ~ 2

Author(s):

Emmy I. Lammertsma ◽

Timme H. Donders ◽

Christof Pearce ◽

Holger Cremer ◽

Evelyn E. Gaiser ◽

...

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Wetland Hydrology ◽

Ice Age ◽

Climate Forcing ◽

Central Florida ◽

The Past ◽

Proxy Records ◽

Hydrological Changes ◽

Multiple Cores

Available proxy records from the Florida peninsula give a varying view on hydrological changes during the late Holocene. Here we evaluate the consistency and sensitivity of local wetland records in relation to hydrological changes over the past ~ 5 ka based on pollen and diatom proxies from peat cores in Highlands Hammock State Park, central Florida. Around 5 cal ka BP, a dynamic floodplain environment is present. Subsequently, a wetland forest establishes, followed by a change to persistent wet conditions between ~ 2.5 and 2.0 ka. Long hydroperiods remain despite gradual succession and basin infilling with maximum wet conditions between ~ 1.3 and 1.0 ka. The wet phase and subsequent strong drying over the last millennium, as indicated by shifts in both pollen and diatom assemblages, can be linked to the early Medieval Warm Period and Little Ice Age, respectively, driven by regionally higher sea-surface temperatures and a temporary northward migration of the Intertropical Convergence Zone. Changes during the 20th century are the result of constructions intended to protect the Highlands Hammock State Park from wildfires. The multiple cores and proxies allow distinguishing local and regional hydrological changes. The peat records reflect relatively subtle climatic changes that are not evident from regional pollen records from lakes.

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Trends in Chesapeake Bay Sedimentation Rates during the Late Holocene

Quaternary Research ◽

10.1016/0033-5894(90)90071-r ◽

1990 ◽

Vol 34 (1) ◽

pp. 33-46 ◽

Cited By ~ 6

Author(s):

Joseph F. Donoghue

Keyword(s):

Sea Level Rise ◽

Chesapeake Bay ◽

Sea Level ◽

Late Holocene ◽

Tide Gauge ◽

Past Century ◽

Sedimentation Rates ◽

Relative Sea Level ◽

The Past ◽

Relative Sea Level Rise

AbstractTrends are discernible in the estimates of late Holocene rates of sedimentation and sea-level rise for the Chesapeake Bay. During most of the Holocene Epoch sedimentation rates and relative sea-level rise were equal, within the limits of measurement, at approximately 1 mm yr−1. Sedimentation rates measured over the past century, however, are nearly an order of magnitude higher, while the rate of relative sea-level rise for the Chesapeake Bay now averages 3.3 mm yr−1, as measured on long-term tide gauge records. When the acceleration in these rates occurred is uncertain, but it appears to have been confined to the past millennium, and probably to the past few centuries. The rapid sedimentation rates recorded during historic time may be a temporary disequilibrium that has resulted from a recent acceleration in the rate of relative sea-level rise.

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Glacier fluctuations during the past millennium in Garibaldi Provincial Park, southern Coast Mountains, British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e07-019 ◽

2007 ◽

Vol 44 (9) ◽

pp. 1215-1233 ◽

Cited By ~ 34

Author(s):

Johannes Koch ◽

John J Clague ◽

Gerald D Osborn

Keyword(s):

British Columbia ◽

Little Ice Age ◽

Ice Age ◽

Southern Coast ◽

Coast Mountains ◽

The Past ◽

Glacier Fluctuations ◽

Garibaldi Provincial Park ◽

Provincial Park ◽

Past Millennium

The Little Ice Age glacier history in Garibaldi Provincial Park (southern Coast Mountains, British Columbia) was reconstructed using geomorphic mapping, radiocarbon ages on fossil wood in glacier forefields, dendrochronology, and lichenometry. The Little Ice Age began in the 11th century. Glaciers reached their first maximum of the past millennium in the 12th century. They were only slightly more extensive than today in the 13th century, but advanced at least twice in the 14th and 15th centuries to near their maximum Little Ice Age positions. Glaciers probably fluctuated around these advanced positions from the 15th century to the beginning of the 18th century. They achieved their greatest extent between A.D. 1690 and 1720. Moraines were deposited at positions beyond present-day ice limits throughout the 19th and early 20th centuries. Glacier fluctuations appear to be synchronous throughout Garibaldi Park. This chronology agrees well with similar records from other mountain ranges and with reconstructed Northern Hemisphere temperature series, indicating global forcing of glacier fluctuations in the past millennium. It also corresponds with sunspot minima, indicating that solar irradiance plays an important role in late Holocene climate change.

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