Ólafur Ingólfsson

University of Iceland | HI · Faculty of Earth Sciences

Crevasse-squeeze ridges (CSRs) are landforms that have been unequivocally linked to surge-type glaciers. The formation of CSRs has been discussed since they were first defined in the mid-1980s. Here, we describe geometric CSR networks from the terrestrial glacier forefields of two glaciers in Trygghamna, Western Svalbard. No gla- cier surges have b...

Both modern and palaeo ice streams experience shutdown which has critical implications for their mass balance and influence on relative sea level. Reconstructions of palaeo-ice streams have mainly focused on their phase of active flow and thus less is understood of their shutdown and style of deglaciation. Mapping of streamlined subglacial bedforms...

Drumlins are important bedforms of former glaciated landscapes as they demonstrate past ice‐flow directions and elucidate processes that operated at the ice/bed interface. Recently mapped drumlins and other streamlined subglacial bedforms in northeast Iceland reveal the flow‐sets of cross‐cutting palaeo‐ice streams that were active within the Icela...

Mapping of streamlined subglacial bedforms (SSBs; drumlins and MSGLs) in NE-Iceland reveals cross-cutting flow-sets of palaeo-ice streams within the Iceland Ice Sheet (IIS) during and following the Last Glacial Maximum (LGM). Here we map ridges (transverse and reticular), hummocky topography, glaciofluvial bedforms and raised shorelines in the Bakk...

Recently mapped drumlins and other streamlined subglacial bedforms (SSBs) in NE-Iceland reveal cross-cutting flow sets of palaeo-ice streams that were active during and following the Last Glacial Maximum (LGM). The Bustarfell drumlin field is located within the Vopnafjörður-Jökuldalsheiði flow set in NE-Iceland and consists of 77 drumlins. The inte...

Recently mapped drumlins and other streamlined subglacial bedforms (SSBs) in NE-Iceland reveal cross-cutting flow sets of palaeo-ice streams that were active during and following the Last Glacial Maximum (LGM). The Bustarfell drumlin field is located within the Vopnafjörður-Jökuldalsheiði flow set in NE-Iceland and consists of 77 drumlins. The inte...

The distal deposition of tephra from explosive volcanism has the potential to geochronologically constrain sedi-mentary archives and landforms. With this technique, we constrain a Late Glacial glacier re-advance on Svalbard and suggest that glacioisostatic emergence rates during the Younger Dryas chronozone were at least three times greater than pr...

We present a 500-year history of naturally felled driftwood incursion to northern Svalbard, directly reflecting regional sea ice conditions and Arctic Ocean circulation. Provenance and age determinations by dendrochronology and wood anatomy provide insights into Arctic Ocean currents and climatic conditions at a fine spatial resolution, as crossdat...

Ice streams are thought to have regulated the past Iceland Ice Sheet (IIS) during and following the Last Glacial Maximum (LGM) by discharging ice and sediment from the interior of the ice sheet towards the shelf edge. Previous assessments of ice streams within the IIS have produced contradictory reconstructions of ice sheet dynamics and location of...

Distally deposited tephra from explosive volcanic eruptions can be a powerful tool for precise dating and correlation of sedimentary archives and landforms. However, the morphostratigraphic and chronological potential of ocean-rafted pumice has been under-utilized considering its long observational history and widespread distribution on modern and...

Arctic precipitation is predicted to increase in the coming century, due to a combination of enhanced northward atmospheric moisture transport and local surface evaporation from ice-free seas. However, large model uncertainties, limited long-term observations, and high spatiotemporal variability limit our understanding of these mechanisms, emphasiz...

We synthesize the current understanding of glacier activity on Svalbard from the end of the Late Pleistocene (12,000 yrs. before present) to the end of the Little Ice Age (c. 1920 AD). Our glacier history is derived from the SVALHOLA database, the first compilation of Holocene geochronology for Svalbard and the surrounding waters, including over 1,...

The sediment-landform assemblages at the recently deglaciated forefields in front of Svalbard's glaciers have been of interest for numerous studies of past glacier dynamics and paleoclimate reconstructions. However, few studies have concentrated on comparing the terrestrial and submarine forefields to gain a holistic approach of the environment. De...

Sediment cores from Kløverbladvatna, a threshold lake in Wahlenbergfjorden, Nordaustlandet, Svalbard were used to reconstruct Holocene glacier fluctuations. Meltwater from Etonbreen spills over a threshold to the lake, only when the glacier is significantly larger than at present. Lithological logging, loss-on-ignition, ITRAX scanning and radiocarb...

Knowledge of the glaciation of central East Iceland between 15 and 9 cal. ka BP is important for the understanding of the extent, retreat and dynamics of the Icelandic Ice Sheet. Crucially, it is not known if the key area of Fljótsdalur‐Úthérað carried a fast‐flowing ice stream during the Last Glacial Maximum; the timing and mode of deglaciation is...

We present a tephra stratigraphical and tephrochronological record from eight lakes in Vestfirðir, NW Iceland. About 50 tephra units have been identified, representing nearly 30 eruptive events originating from five volcanic systems: Hekla, Katla, Snæfellsjökull, Grímsvötn and Veiðivötn‐Bárðarbunga. Most of the tephra layers originate from Grímsvöt...

Despite warming regional conditions and our general understanding of the deglaciation, a variety of data suggest glaciers re-advanced on Svalbard during the Lateglacial–early Holocene (LGEH). We present the first well-dated end moraine formed during the LGEH in De Geerbukta, NE Spitsbergen. This landform was deposited by an outlet glacier re-advanc...

The study of glacial landforms is important for understanding past subglacial processes and dynamics. The Nordenskiöldbreen forefield hosts numerous streamlined landforms resulting from a late Holocene glacier advance. Here, we present a geomorphological map constructed from remotely sensed imagery of both the marine and terrestrial environments. S...

GRANTISM (GReenland and ANTarctic Ice Sheet Model) is an educational Excel™ model introduced by Pattyn (2006). Here, GRANTISM is amended to simulate the Svalbard-Barents-Sea Ice Sheet during the Last Glacial Maximum, an analogue for the contemporary West Antarctic Ice Sheet. A new name, “GRANTSISM,” is suggested; the added S represents Svalbard. GR...

Evidence of a dynamic Holocene glacial history is preserved in the terrestrial and marine archives of St. Jonsfjorden, a small fjord-system on the west coast of Spitsbergen, Svalbard. High-resolution, remotely sensed imagery from marine and terrestrial environments was used to construct geomorphological maps that highlight an intricate glacial hist...

• Digital Elevation Models produced to quantify glacier surges of Drangajökull ice cap. • The surges of Drangajökull are in contrast to the bigger ice caps in Iceland. • Development of Drangajökull surges resemble Svalbard surge-type. • Environmental conditions might explain proceeding of Drangajökull surges. Surface elevation and volume changes o...

A new and improved Holocene tephra stratigraphy and tephrochronological framework for eastern and northern Iceland is presented. Investigations of a sediment sequence from Lake L€ ogurinn have revealed a comprehensive tephra record spanning the last 10.200 years. A total of 157 tephra layers have been identified, whereof 149 tephra layers have been...

The drumlin field at Múlajökull, Iceland, is considered to be an active field in that partly and fully ice-covered drumlins are being shaped by the current glacier regime. We test the hypothesis that the drumlins form by a combination of erosion and deposition during successive surge cycles. We mapped and measured 143 drumlins and studied their str...

Stratigraphic and morphologic data previously collected from the forefield of Múlaj€ okull, Iceland, suggest that its recent surge cycles are responsible for the formation of drumlins there and that their relief reflects both deposition on drumlins and erosion between them. We have tested these ideas and aspects of leading models of drumlin formati...

Most glaciers and ice caps in Iceland experienced rapid deglaciation in the early Holocene, reaching a minimum extent during the Holocene Thermal Maximum. Here we present evidence of the Holocene glacial history from lake sediment cores retrieved from seven threshold lakes around the Drangajökull ice cap in the Vestfirðir peninsula, NW Iceland. The...

Fláajökull is a non-surging outlet glacier draining the south-eastern part of the Vatnajökull, southeast Iceland. Fláajökull was stationary or advanced slightly between 1966 and 1995 and formed a prominent end moraine. Glacial retreat since then has revealed a cluster of 15 drumlins. This study focuses on the morphology and sedimentology of the dru...

Surging glaciers are potential analogues for land-terminating palaeo-ice streams and surging ice sheet lobes, and research on surge-type glaciers is important for understanding the causal mechanisms of modern and past ice sheet instabilities. The geomorphic signatures left by the Icelandic surge-type glaciers vary and range from glaciotectonic end...

The deglaciation of the Late Weichselian Icelandic ice sheet was extremely rapid, and marked by a collapse of its marine-based sections between 15.0 and 14.7 ka BP. We present a conceptual two-dimensional glacio-isostatic equilibrium model that describes the effect of simultaneous glacio-isostatic responses to changes in glacier load on the crust a...

We present twenty-four new cosmogenic isotope (³⁶Cl) surface exposure ages from erratic boulders, moraine boulders and glacially eroded bedrock that constrain the late Weichselian to Holocene glacial history of the Drangajökull region, northwest Iceland. The results suggest a topographically controlled ice sheet over the Vestfirðir (Westfjords) pen...

Time-series of digital elevation models (DEMs) of the forefield of the Brúarjökull surge-type glacier in Iceland were used to quantify the volume of material that was mobilized by the 1963-1964 surge. The DEMs were produced by stereophotogrammetry on aerial photographs from before the surge (1961) and after (1988 and 2003). The analysis was perform...

The internal architecture and structural evolution of the Arnarfellsmúlar terminal moraine at Múlajökull, a surge-type glacier in central Iceland, is described in order to demonstrate submarginal and proglacial glaciotectonic processes during glacier surging, as well as constraining the age of the maximum extent of the glacier. The moraine is 4–7 m...

Over the last 300 years, each of the three surge-type outlet glaciers of the Drangajökull ice cap in northwest Iceland has surged 2-4 times. There is valuable historical information available on the surge frequencies since the ‘Little Ice Age’ (LIA) maximum because of the proximity of the surging outlets, Reykjarfjarðarjökull, Leirufjarðarjökull an...

At the Last Glacial Maximum, Iceland was covered by an ice sheet more than 2000 m thick reaching as far as the shelf break. Rapid deglaciation, controlled by rising global sea level, started between 18.6 and 15.0 cal kyrs BP. In Bølling times, between 15.0 and 14.7 cal kyrs BP, the marine based part of the ice sheet collapsed and glaciers retreated...

While there are numerous hypotheses concerning glacial–interglacial environmental and climatic regime shifts in the Arctic Ocean, a holistic view on the Northern Hemisphere's late Quaternary ice-sheet extent and their impact on ocean and sea-ice dynamics remains to be established. Here we aim to provide a step in this direction by presenting an ove...

To better understand Pleistocene climatic changes in the Arctic, integrated palaeoenvironmental and palaeoclimatic signals from a variety of marine and terrestrial geological records as well as geochronologic age control are required, not least for correlation to extra-Arctic records. In this paper we discuss, from an Arctic perspective, methods an...

The behaviour of ice sheets and their geologic imprints in fjord regions are often multifaceted. Fjords, which were temporarily occupied by fast flowing ice-streams during major glaciations, and inter-fjord areas, which were covered by less active ice, show different signatures of past glaciations. The land and marine records of glaciations over th...

Research campaigns over the last decade have yielded a growing stream of data that highlight the dynamic nature of Arctic cryosphere and climate change over a range of time scales. As a consequence, rather than seeing the Arctic as a near static environment in which large scale changes occur slowly, we now view the Arctic as a system that is typifi...

Supplemantary data with the paper The drumlin field and the geomorphology of the Múlajökull surge-type glacier, central Iceland.

While there are numerous hypotheses concerning glacialeinterglacial environmental and climatic regime shifts in the Arctic Ocean, a holistic view on the Northern Hemisphere's late Quaternary ice-sheet extent and their impact on ocean and sea-ice dynamics remains to be established. Here we aim to provide a step in this direction by presenting an ove...

While there are numerous hypotheses concerning glacialeinterglacial environmental and climatic regime shifts in the Arctic Ocean, a holistic view on the Northern Hemisphere's late Quaternary ice-sheet extent and their impact on ocean and sea-ice dynamics remains to be established. Here we aim to provide a step in this direction by presenting an ove...

The recent discovery of a subfossil polar bear (Ursus maritimus) jawbone in the Poolepynten coastal cliff sequence, western Svalbard, and its implications for the natural history of the polar bear motivated an effort to better constrain the environmental history and age envelope of the Poolepynten sediment sequence. The focus of the present study i...

Twenty six Icelandic outlet glaciers, ranging from 0.5-1.500 km2, are known to surge, with terminal advances ranging from of few tens of meters to about 10 km. The geomorphic signatures of surges vary, from large-scale folded and thrusted end moraine systems, extensive dead-ice fields and drumlinized forefields to drift sheets where fast ice-flow i...

The history of research on the Late Quaternary SvalbardeBarents Sea ice sheet mirrors the developments of ideas and the shifts of paradigms in glacial theory over the past 150 years. Since the onset of scientific research there in the early 19th Century, Svalbard has been a natural laboratory where ideas and concepts have been tested, and played an...

Stratigraphic boundaries are ideally defined by distinct lithological, geochemical, and palaeobiological signa-tures, to which a chronological framework can be applied. We present a range of observations that illustrate how the Holocene–Anthropocene transition meets these criteria in its expression in sediments from remote arctic and alpine lakes,...

Hybridization is a widespread evolutionary phenomenon that can play a role in diversification, especially among closely related taxa. Whereas hybridization is well known in plants, natural animal hybrids are considered much less common, although recent genome-wide investigations of canids and hominids suggest that admixture may have shaped the evol...

Abstract – The geomorphology and sedimentology of the Teigarjökull and Búrfellsjökull, two small surge-type cirque glaciers at the Tröllaskagi peninsula, northern Iceland was explored for improved understanding of their surge imprints. Geomorphological, geological and remote sensing data on sediments and landforms were used for developing a geomorp...

Glaciers and ice sheets have existed in Antarctica for more than 30My, and it is the most stable cryospheric system on Earth. This article starts with a very brief overview of the pre-Quaternary glacial history of Antarctica. The Pleistocene history of the Antarctic Ice Sheet is outlined, and the glacial history of Antarctica since the Last Glacial...

While glaciation of Antarctica began as early as the Oligocene, glaciation of South America and Greenland started only some 14. Ma. Continental-scale glaciation of the Northern Hemisphere began only some 1. Ma in the Late Matuyama Chron, although smaller-scale glaciation was established in Greenland and Iceland at the beginning of the Quaternary. S...

Glaciers and ice sheets have existed in Antarctica for more than 30My, and it is the most stable cryospheric system on Earth. This article starts with a very brief overview of the pre-Quaternary glacial history of Antarctica. The Pleistocene history of the Antarctic Ice Sheet is outlined, and the glacial history of Antarctica since the Last Glacial...