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An end moraine (Vassryggen) and associated sandur, described by Jens Esmark as early as 1824, was the first pre-Neoglacial glacigenic landform association to be recognised as such. It forms the most important element of a range of evidence used by Esmark in support of his continental-scale glaciation hypothesis. The career of Esmark, who became a f...
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... rationale of undertaking the translation is of special relevance to the historical development of the glacial theory in Britain. It arose through the initiative of Robert Jameson , who occupied the chair of Regius Professor of Natural History in the University of Edinburgh from 1804 to 1854 (Fig. 7). Jameson, like Esmark, had attended classes given by Abraham Werner at the Freiberg Mining Academy. In his case it was from 1800 only to 1802, when the death of his father forced his return to Scotland. During his time at Freiberg he was converted into Neptunism's most devoted and ardent disciple (Davis, 1969: p147). On March 3rd 1808 ...
Citations
... near the moraine to 35 m a.s.l. on top of another glaciomarine delta close to the sea and located about 33-35 m a. s.l. (Bergstrøm et al., 2010;Karlsen, 2016;Worsley, 2006). Prior work also has shown that this latter delta, which now has been largely removed by gravel mining, was fed by meltwater rivers from the Esmark and Lysefjorden moraines and form the Marine Limit, corresponding with the peak level of a sea-level rise near the end of the Younger Dryas (Anundsen, 1985). ...
... Given Otto Tank's exclamation, I have found it appropriate to name this moraine at Rauddalsbreen Otto Tank's Moraine in honour and memory of Esmark's enthusiastic young student (Hestmark 2017(Hestmark , 2018 (Fig. 7). The big gravel ridge at Forsand has been known informally as the Esmark Moraine for many years, and is now considered to have been deposited by an enormous valley glacier tongue at the end of the cold Younger Dryas, c. 11 500 years ago, at the end of the last Ice Age (Weichselian) (Andersen 1954(Andersen , 1992Worsley 2006;Briner et al. 2014). ...
The discovery of Ice Ages is one of the most revolutionary advances ever made in the Earth sciences. In Norway this discovery was made by Danish-Norwegian geoscientist Jens Esmark and his young student Niels Otto Tank, who on a mountain traverse in early september 1823 observed a number of geomorphological features produced by an extant glacier, and compared these to similar features they had previously noted where glaciers today are absent. Seing a recent moraine pushed up by an extant glacier they suddenly realized that a big ridge of gravel they had earlier seen at sea level in Southern Norway had to be an ancient moraine, deposited by a big glacier at a time when the climate was substantially colder than today. The brevity of Esmark's account made the precise location of the site of enlightenment remained a mystery for almost two hundred years until it was rediscovered by the author in 2008. This paper describes the crucial site and its lessons.
... • That along the coast Esmark and his companions observed several traces and deposits close to sea level and far from glaciers, and that at some point they realised that these indicated the former presence of large glaciers down to sea level: (i) at Forsand, close to Stavanger and the entrance of spectacular Lysefjord, they observed a long rampart across a valley, consisting of an unsorted mixture of sand, gravel and big boulders. This ridge is locally known as Vassrygg and was later named the Esmark Moraine (Andersen 1954;Worsley 2006;Briner et al. 2014); and (ii) at the Sula archipelago at the entrance of the Sognefjord a presumably glacier-polished conglomerate cliff (Hestmark 2009a It has often been assumed that Esmark, faced with the curious Vassryggen at Forsand, there and then realised that it was an ancient moraine, and on the spot developed his vision of former large scale glaciations down to sea level (e.g. Engen 1985). ...
... While much has been made of the significance of the Esmark Moraine in previous analyses of Esmark 's discovery (e.g. Strøm 1950;Andersen 1992;Worsley 2006), it has been largely overlooked that Esmark puts equal weight on the sandur in front of the moraine. The outwash plain east of Otto Tank's Moraine is indeed a beautiful example of this feature created by glacial streams, with braided rivers depositing their light particles in the aptly named Ytste Leivatnet (Upper Clay Lake) at 1015 m a.s.l. ...
The discovery of Ice Ages is one of the most revolutionary advances made in the Earth sciences. In 1824 Danish-Norwegian geoscientist Jens Esmark published a paper stating that there was indisputable evidence that Norway and other parts of Europe had previously been covered by enormous glaciers carving out valleys and fjords, in a cold climate caused by changes in the eccentricity of Earth's orbit. Esmark and his travel companion Otto Tank arrived at this insight by analogous reasoning: enigmatic landscape features they observed close to sea level along the Norwegian coast strongly resembled features they observed in the front of a retreating glacier during a mountain traverse in the summer of 1823. Which glacier they observed up close has however remained a mystery, and thus an essential piece of information in the story of this discovery has been missing. Based on previously unknown archive sources, supplemented by field study, I here identify the key locality as the glacier Rauddalsbreen. This is the northernmost outlet glacier from Jostedalsbreen, the largest glacier in mainland Europe. Here the foreland exposed by glacier retreat since the Little Ice Age maximum around AD 1750 contains a rich collection of glacial deposits and erosional forms. The point of enlightenment is more precisely identified to be a specific moraine and its distal sandur at 61°53′26″N, 7°26′43″E. In memory of Esmark's travel companion who possibly was the first to realise the analogy, it is proposed to name this moraine Otto Tank's Moraine, a pendant to the already famous Esmark Moraine at Forsand by the sea.
... Esmark is today mostly remembered for his pioneer ascents of many of Norway's highest peaks (Esmark, 1802(Esmark, , 1812Hestmark, 2009), his discovery of ice ages, and his astronomical explanation of such dramatic climate change as caused by variations in the eccentricity of the orbit of the Earth, a hypothesis now recognized as a precursor of the theories of James Croll andMilutin Milankovich (Esmark, 1824, 1826;Andersen, 1992;Worsley, 2006;Rudwick, 2008;Berger, 2012;Krüger, 2013). In his own lifetime he was primarily known as a skilful mineralogist and geologist. ...
In 2010 we rediscovered the complete set of meteorological observation protocols made by Jens Esmark (1762–1839) during his years of residence in the Norwegian capital of Oslo (then Christiania). From 1 January 1816 to 25 January 1839, Esmark at his house in Øvre Voldgate in the morning, early afternoon and late evening recorded air temperature with state-of-the-art thermometers. He also noted air pressure, cloud cover, precipitation and wind directions, and experimented with rain gauges and hygrometers. From 1818 to the end of 1838 he twice a month provided weather tables to the official newspaper Den Norske Rigstidende, and thus acquired a semi-official status as the first Norwegian state meteorologist. This paper evaluates the quality of Esmark's temperature observations and presents new metadata, new homogenization and analysis of monthly means. Three significant shifts in the measurement series were detected, and suitable corrections are proposed. The air temperature in Oslo during this period is shown to exhibit a slow rise from 1816 towards 1825, followed by a slighter fall again towards 1838.
... Our rediscovery in 2010 of Esmark's original meteorological observation protocols has provided an opportunity to digitize, homogenize and analyse his data with modern methods. Esmark is today mostly remembered for his pioneer ascents of many of Norway's highest peaks (Esmark, 1802Esmark, , 1812 Hestmark, 2009), his discovery of ice ages, and his astronomical explanation of such dramatic climate change as caused by variations in the eccentricity of the orbit of the Earth, a hypothesis now recognized as a precursor of the theories of James Croll and Milutin Milankovich ( Andersen, 1992; Worsley, 2006; Rudwick, 2008; Berger, 2012; Krüger, 2013). In his own lifetime he was primarily known as a skilful mineralogist and geologist. ...
... The first coupling between sediment ridges and former glacier extent was in 1824 when Jens Esmark described a 15 m high gravelly ridge in Norway as emplaced by a former glacier (Esmark, 1824(Esmark, , 1826, and developed his hypothesis on continental glaciations (Andersen, 1992). Although the idea was met by skepticism, it was acknowledged by Buckland (1840), and included in the Ice Age Theory of Agassiz (1840-1) (see Worsley, 2006). The ridge was referred as The Esmark Moraine as early as the 1860s, and this observation denoted the start of a tradition whereby sediment morphology attributed to changing glacier extent was used to reconstruct the paleoclimate (see Ing olfsson and Landvik, 2013). ...
Svalbard is a key area for the investigation of glacial surges, and almost two centuries worth of field observations exists from this region. Studies have shown that the course of a surge and the associated formation of landforms are strongly influenced by basinal factors, and that the broad range of variables involved can hamper interpretations and comparisons. Based on a review of surges in Svalbard, a new concept for glacial geological investigations has been developed that combines ice-flows, ice-front movements, and morphostratigraphy. The concept is comprised of the following four elements: 1) classification based on the configuration and characteristics of the receiving basin, 2) division of the surge cycle into six stages, 3) guidelines for morphological mapping, and 4) use of an allostratigraphic approach for interpreting ice-front movements. In this context, delineation of the active phase is critical, which include the history of terminus movements, and four main categories of receiving basins are recognized. These are (A) terrestrial basins with deformable substrates, (B) terrestrial basins with poorly deformable substrates, (C) shallow water basins, and (D) deep water basins. The ice-front movement history is reconstructed by coupling information from the proglacial moraines (syn-surge), the supraglacial moraines (post-surge), and the associated traces of meltwater to the surge stages (I-VI). This approach has revealed a critical relationship between the termination of the active phase and three morphological elements, namely, the maximum ice-front position, the maximum moraine extent and the youngest proglacial moraine, which are unique for each of the basins A-D. The concept is thus a novel and more precise approach for mapping the active phase and the active phase duration, as shown by the ~12-year long surge of Fridtjovbreen, where stage I was 30 months (inception), stage II was 54 months (ice-front advance), stage III was 12 months (stillstand), and stage IV was 48 months (retreat during active flow). The glacier has been in quiescent phase (stages V/VI) since 2002.
... We sampled bedrock and erratic boulders from a bedrock hill $100 m above sea level (a.s.l.) and $3.5 km beyond (north-west of) the Lysefjorden Moraine at the mouth of the fjord (Fig. 3). We also collected a sample from striated bedrock immediately inboard of the Lysefjorden Moraine at the fjord mouth, not far from the classic Esmark (Vassryggen) Moraine (Worsley, 2006). We also collected samples of iceeroded bedrock from 9 and 24 km up fjord. ...
We present 34 new cosmogenic 10Be exposure ages that constrain the Lateglacial (Bølling–Preboreal) history of the Scandinavian Ice Sheet in the Lysefjorden region, south-western Norway. We find that the classical Lysefjorden moraines, earlier thought to be entirely of Younger Dryas age, encompass three adjacent moraines attributed to at least two ice sheet advances of distinctly different ages. The 10Be age of the outermost moraine (14.0 ± 0.6 ka; n = 4) suggests that the first advance is of Older Dryas age. The innermost moraine is at least 2000 years younger and was deposited near the end of the Younger Dryas (11.4 ± 0.4 ka; n = 7). After abandonment of the innermost Lysefjorden Moraine, the ice front receded quickly towards the head of the fjord, where recession was interrupted by an advance that deposited the Trollgaren Moraine at 11.3 ± 0.9 ka (n = 5). 10Be ages from the inboard side of the Trollgaren Moraine suggest final retreat by 10.7 ± 0.3 ka (n = 7). The late culmination of the Younger Dryas advance contrasts with other sectors of the Scandinavian Ice Sheet where the margin appears to have culminated earlier during the Younger Dryas stadial, followed by retreat during the middle and late part of the Younger Dryas.
... Esmark is today mostly remembered for his pioneer ascents of many of Norway's highest peaks (Esmark, 1802(Esmark, , 1812Hestmark, 2009), his discovery of ice ages, and his astronomical explanation of such dramatic climate change as caused by variations in the eccentricity of the orbit of the Earth, a hypothesis now recognized as a precursor of the theories of James Croll andMilutin Milankovich (Esmark, 1824, 1826;Andersen, 1992;Worsley, 2006;Rudwick, 2008;Berger, 2012;Krüger, 2013). In his own lifetime he was primarily known as a skilful mineralogist and geologist. ...
The Arctic land areas have experienced greater warming over the last
three decades than elsewhere in the world. In Europe the Svalbard
archipelago (located in the North Atlantic sector of the Arctic Ocean
from 74° to 81°N and 10° to 35°E) have experienced the
greatest temperature change during this period. At Svalbard airport the
mean annual air temperature has increased by approximately 4 °C
since 1980. Air temperatures on Svalbard are highly sensitive to the
coupled sea ice-ocean-atmosphere system and recent studies suggest that
the shrinkage in Arctic sea-ice cover is the most important factor for
the record high temperatures. Continuous temperature series from two
instrumented permafrost boreholes (102 m and 15 m deep) on
Janssonhaugen, Svalbard, provide main data for the present analysis. The
boreholes are located 23 km from Svalbard Airport and were established
in 1998 within the EU-funded PACE project and are designed for long-term
temperature monitoring. In this study we examine the impact of the
recent atmospheric warming on the permafrost in Svalbard. Trends and
variability in permafrost temperatures at different depths are compared
to trends in air temperature and ground surface temperatures. Although
Janssonhaugen is representative for exposed sites where snow cover
typically is thin or absent, the altered effect of a thin snow cover on
subsurface thermal regime has not been analysed in detail so far. The
effect of variability in snow cover on ground temperatures is studied
and quantified by combined use of snow cover modeling, 1-D transient
heat flow modeling and advanced time-series analyses. The study gives
new insights into permafrost response and sensitivity to climate change,
including effects of more frequent anomalous weather events.
... Some of the earliest steps in the history of British glacial theory are recently reviewed in this journal, (Worsley 2006). One perplexing aftermath of Louis Agassiz's famed visit in 1840, is that after a short euphoric phase, when senior geologists such as William Buckland and Charles Lyell declared their conversion to the land ice hypothesis, very serious doubts started to reassert themselves. ...
... Further retreat freed many of the fjords, but during the subsequent Younger Dryas climatic deterioration a widespread glacier resurgence was induced and some recently abandoned cirques were reoccupied. This is the same re-advance event which led to the construction of the Vassrygg end moraine in S W Norway (Worsley 2006). This Younger Dryas readvance is often delineated by a chain of prominent moraine ridges, especially in the fjords, with Holandsfjord and the Bergsfjord Peninsula being no exceptions to this model. ...
During the two decades after 1841, the Glacial Theory was, at best, quiescent in Britain. The 1865 expedition arose from a progressive resurgence of interest in glacigenic sediments. The members were three young Geological Survey officers, Archibald and James Geikie and William Whitaker, all with recent drift mapping experience. Their objectives included making 'actualistic' observations of modern glaciers, comparing Norwegian and Scottish glacial features, and better comprehending glacial deposits, both ancient and modern. Field investigations were focused on two areas of Arctic Norway - Holandsfjord (Nordland) and Bergsfjord Peninsula (Tromsø-Finnmark). Their work produced the earliest known detailed glacial geological analysis (including accurate drawings, sketches, maps and cross sections) of any Scandinavian ice-marginal environments. These data permit a comparison of ice marginal and proglacial environmental changes between 1865 and the present day associated with the key Holandsfjord glaciers-Engabreen and Fondalsbreen. The characters of the ice margins in 1865 and 2005 are compared and, in conjunction with other observations, yield one of the most comprehensive records of Neoglaciation anywhere. In the Bergsfjord Peninsula, the 1865 details are more sparse, except for the Jøkulfjord regenerated glacier. The impact of the 1865 work on the Glacial Theory and subsequent careers of the participants was clearly significant.
... Esmark is today mostly remembered for his pioneer ascents of many of Norway's highest peaks (Esmark, 1802(Esmark, , 1812Hestmark, 2009), his discovery of ice ages, and his astronomical explanation of such dramatic climate change as caused by variations in the eccentricity of the orbit of the Earth, a hypothesis now recognized as a precursor of the theories of James Croll andMilutin Milankovich (Esmark, 1824, 1826;Andersen, 1992;Worsley, 2006;Rudwick, 2008;Berger, 2012;Krüger, 2013). In his own lifetime he was primarily known as a skilful mineralogist and geologist. ...
