Holocene alluvial stratigraphy and response to climate change in the Roaring River valley, Front Range, Colorado, USA

AbstractStratigraphic analyses and radiocarbon geochronology of alluvial deposits exposed along the Roaring River, Colorado, lead to three principal conclusions: (1) the opinion that stream channels in the higher parts of the Front Range are relics of the Pleistocene and nonalluvial under the present climate, as argued in a water-rights trial USA v. Colorado, is untenable, (2) beds of clast-supported gravel alternate in vertical succession with beds of fine-grained sediment (sand, mud, and peat) in response to centennial-scale changes in snowmelt-driven peak discharges, and (3) alluvial strata provide information about Holocene climate history that complements the history provided by cirque moraines, periglacial deposits, and paleontological data. Most alluvial strata are of late Holocene age and record, among other things, that: (1) the largest peak flows since the end of the Pleistocene occurred during the late Holocene; (2) the occurrence of a mid- to late Holocene interval (~ 2450–1630(?) cal yr BP) of warmer climate, which is not clearly identified in palynological records; and (3) the Little Ice Age climate seems to have had little impact on stream channels, except perhaps for minor (~ 1 m) incision.

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Signals of Medieval Warm Period and Little Ice Age from southwestern Madhya Pradesh (India): A pollen-inferred Late-Holocene vegetation and climate change

Quaternary International ◽

10.1016/j.quaint.2013.07.011 ◽

2014 ◽

Vol 325 ◽

pp. 74-82 ◽

Cited By ~ 30

Author(s):

M.F. Quamar ◽

M.S. Chauhan

Keyword(s):

Climate Change ◽

Little Ice Age ◽

Late Holocene ◽

Medieval Warm Period ◽

Madhya Pradesh ◽

Warm Period ◽

Ice Age ◽

Vegetation And Climate

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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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Application of the Handysurf E-35B electronic profilometer for the study of weathering micro-relief in glacier forelands in SE Iceland

Acta Geologica Polonica ◽

10.1515/agp-2015-0018 ◽

2015 ◽

Vol 65 (3) ◽

pp. 389-401 ◽

Cited By ~ 4

Author(s):

Maciej Dąbski

Keyword(s):

Time Scales ◽

Little Ice Age ◽

Major Change ◽

Limited Range ◽

Ice Age ◽

Rock Surface ◽

Schmidt Hammer ◽

Fine Grained ◽

Relative Dating ◽

Roughness Measurements

AbstractThis article presents the results of weathering micro-roughness measurements performed with the use of a Handy-surf E-35B electronic profilometer, a new tool in geomorphological studies. Measurements were performed on glacially abraded basaltic surfaces within the Little Ice Age (LIA) glacial forelands of Hoffelsjökull, Fláajökull, Skálafellsjökull and Virkisjökull in Iceland. Results show a statistical increase in micro-roughness in a direction from the glacial termini to LIA moraines. However, a major change in the micro-roughness of basaltic surfaces only occurs during the first 80 to 100 years since the onset of subaerial weathering. Increase in rock surface micro-roughness is accompanied by an increase in weathering rind thickness and a decrease in Schmidt hammer R-values. Micro-roughness measurements with the use of the Handysurf E-35B can provide insights into initial rates of rock surface micro-relief development. The use of this instrument as a relative dating technique is limited to fine-grained rocks and decadal time-scales of weathering because of the limited range of measureable micro-relief amplitude.

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The Norse in Greenland and late Holocene sea-level change

Polar Record ◽

10.1017/s0032247407006948 ◽

2008 ◽

Vol 44 (1) ◽

pp. 45-50 ◽

Cited By ~ 17

Author(s):

Naja Mikkelsen ◽

Antoon Kuijpers ◽

Jette Arneborg

Keyword(s):

Sea Level ◽

Little Ice Age ◽

Late Holocene ◽

Ice Age ◽

Documentary Evidence ◽

Sea Level Changes ◽

Middle Holocene ◽

Level Change ◽

Farming Community ◽

Holocene Sea Level

ABSTRACTNorse immigrants from Europe settled in southern Greenland in around AD 985 and managed to create a farming community during the Medieval Warm Period. The Norse vanished after approximately 500 years of existence in Greenland leaving no documentary evidence concerning why their culture foundered. The flooding of fertile grassland caused by late Holocene sea-level changes may be one of the factors that affected the Norse community. Holocene sea-level changes in Greenland are closely connected with the isostatic response of the Earth's crust to the behaviour of the Greenlandic ice sheet. An early Holocene regressive phase in south and west Greenland was reversed during the middle Holocene, and evidence is found for transgression and drowning of early-middle Holocene coast lines. This drowning started between 8 and 7ka BP in southern Greenland and continued during the Norse era to the present. An average late Holocene sea level rise in the order of 2–3 m/1000 years may be one of the factors that negatively affected the life of the Norse Greenlanders, and combined with other both socio-economic and environmental problems, such as increasing wind and sea ice expansion at the transition to the Little Ice Age, may eventually have led to the end of the Norse culture in Greenland.

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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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Late Glacial and Late Holocene Moraines in the Cerros Cuchpanga, Central Peru

Quaternary Research ◽

10.1016/0033-5894(84)90068-1 ◽

1984 ◽

Vol 21 (3) ◽

pp. 275-285 ◽

Cited By ~ 44

Author(s):

H.E. Wright

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Late Glacial ◽

Ice Age ◽

Recent Past ◽

Valley Bottom ◽

Radiocarbon Dates ◽

Western Cordillera ◽

Limestone Bedrock ◽

Ice Field

Small ice fields on the western cordillera northeast of Lima were expanded to three times their present size in the recent past, and the regional snow line was probably about 100 m lower than it is today. Outwash from the expanded glaciers formed deltas of silt in valley-bottom lakes. When the ice lobes retreated, the reduced outwash was trapped behind recessional moraines, and the clear meltwater infiltrated into the limestone bedrock and emerged at the heads of the deltas in spring pools. The delta surfaces then became covered with peat, and radiocarbon dates for the base of the peat (1100 ± 70 and 430 ± 70 yr B.P. for two different deltas) indicate that the maximum ice advance was older than those dates and, thus, older than the Little Ice Age of many north-temperate regions. Much older moraines date from expansion of the same local summit glaciers to even lower levels in the main valleys, which had previously been inundated by the cordilleran ice field. The cordilleran deglaciation and this expansion of local glaciers probably occurred between 12,000 and 10,000 yr ago, on the basis of slightly contradictory radiocarbon dates.

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Late Holocene climate variability in the southwestern Mediterranean region: an integrated marine and terrestrial geochemical approach

Climate of the Past Discussions ◽

10.5194/cpd-6-1655-2010 ◽

2010 ◽

Vol 6 (5) ◽

pp. 1655-1683 ◽

Cited By ~ 8

Author(s):

C. Martín-Puertas ◽

F. Jiménez-Espejo ◽

F. Martínez-Ruiz ◽

V. Nieto-Moreno ◽

M. Rodrigo ◽

...

Keyword(s):

Climate Variability ◽

North Atlantic ◽

Little Ice Age ◽

Mediterranean Region ◽

Late Holocene ◽

Western Mediterranean ◽

Warm Period ◽

Ice Age ◽

The North ◽

The North Atlantic

Abstract. A combination of marine (Alboran Sea cores, ODP 976 and TTR 300 G) and terrestrial (Zoñar Lake, Andalucia, Spain) paleoclimate information using geochemical proxies provides a high resolution reconstruction of climate variability and human influence in southwestern Mediterranean region for the last 4000 years at inter-centennial resolution. Proxies respond to changes in precipitation rather than temperature alone. Our archive documents a succession of dry and wet periods coherent with the North Atlantic climate signal. Drier stages occurred prior to 2.7 cal ka BP, well-correlated with the global aridity crisis of the third-millennium BC, and during the Medieval Warm Period (1.4–0.7 cal ka BP). Wetter conditions prevailed from 2.7 to 1.4 cal ka BP and after the Medieval Warm Period and the onset of the Little Ice Age. Hydrological signatures during the Little Ice Age are highly variable but consistent with more humidity that the period before. Additionally, Pb anomalies in sediments at the end of Bronze Age suggest anthropogenic pollution earlier than the Roman Empire development in the Iberian Peninsula. The evolution of the climate in the study area during the Late Holocene confirms the see-saw pattern previously shown between eastern and western Mediterranean regions and suggests a higher influence of the North Atlantic dynamics in the western Mediterranean.

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Neoglaciation in the Southern Kenai Mountains, Alaska

Annals of Glaciology ◽

10.1017/s0260305500008831 ◽

1990 ◽

Vol 14 ◽

pp. 319-322 ◽

Cited By ~ 8

Author(s):

Gregory C. Wiles ◽

Parker E. Calkin

Keyword(s):

Little Ice Age ◽

Late Holocene ◽

Ice Age ◽

Past Century ◽

Partial Control ◽

The Past ◽

Proglacial Lakes ◽

Glacial Chronology ◽

Historical Accounts ◽

Ice Complex

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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