English
norskBlar i forfatter "Kjellman, Sofia Elisabeth"
Viser treff 1-12 av 12
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Ancient sedimentary DNA shows rapid post-glacial colonisation of Iceland followed by relatively stable vegetation until the Norse settlement (Landnám) AD 870
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-08)Understanding patterns of colonisation is important for explaining both the distribution of single species and anticipating how ecosystems may respond to global warming. Insular flora may be especially vulnerable because oceans represent severe dispersal barriers. Here we analyse two lake sediment cores from Iceland for ancient sedimentary DNA to infer patterns of colonisation and Holocene vegetation ... -
Arctic and sub-Arctic lake water δ2H and δ18O along a coastal-inland transect: Implications for interpreting water isotope proxy records
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-04)High-latitude lakes are sensitive to climate change and store information about large-scale circulation changes and catchment-integrated processes. Lakes are mainly recharged by meteoric water, meaning that some lake sediment proxies may indirectly archive the stable isotopic composition of hydrogen (δ<sup>2</sup> H) and oxygen (δ<sup>18</sup>O) of past precipitation. Yet, despite similar ... -
Climatic impacts on an Arctic lake since 1300 AD: a multi-proxy lake sediment reconstruction from Prins Karls Forland, Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-10-31)On the remote Arctic archipelago of Svalbard, there is increasing evidence of environmental impacts from climate change. The analysis of lake sedimentary records can be used to assess how strongly these recent changes have altered lake ecosystems. Sediments deposited during the last millennium from Lake Blokkvatnet, Prins Karls Forland, were analysed using a multiproxy approach, including stable ... -
A complete Holocene lake sediment ancient DNA record reveals long-standing high Arctic plant diversity hotspot in northern Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-09)Arctic hotspots, local areas of high biodiversity, are potential key sites for conservation of Arctic biodiversity. However, there is a need for improved understanding of their long-term resilience. The Arctic hotspot of Ringhorndalen has the highest registered diversity of vascular plants in the Svalbard archipelago, including several remarkable and isolated plant populations located far north of ... -
Evolution and temporal constraints of a multiphase postglacial rock slope failure
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-05)Large rock slope failures are temporal processes which act to modify the landscape after glacial retreat. The slope failure process often shows a lag time of thousands of years after deglaciation, with multiple failure events possible. While global datasets constrain this lag time from extensive mapping and dating of paraglacial rock avalanches, the timeline is poorly refined in northern Norway. We ... -
Geomorphology and surficial geology of the Femmilsjøen area, northern Spitsbergen
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-09)Climate change is amplified in the Arctic, and establishing baseline data for its current character is important. Here we present a map of the geomorphology of the Femmilsjøen area, Spitsbergen, northern Svalbard. The regional physiography is characterised by a low-relief, high elevation mountain plateau, its high-relief steep slopes, and low-relief coastal lowlands. The results indicate that glaciers ... -
Glacial history of the Åsgardfonna Ice Cap, NE Spitsbergen, since the last glaciation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-30)The response of glaciers and ice caps to past climate change provides important insight into how they will react to ongoing and future global warming. In Svalbard, the Holocene glacial history has been studied for many cirque and valley glaciers. However, little is known about how the larger ice caps in Svalbard responded to Late Glacial and Holocene climate changes. Here we use lake sediment cores ... -
Holocene precipitation seasonality in northern Svalbard: Influence of sea ice and regional ocean surface conditions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-13)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, emphasizing the need for paleoclimate records of precipitation ... -
Holocene precipitation seasonality on Svalbard and in Northern Fennoscandia reconstructed using organic geochemical and stable isotope proxies
(Doctoral thesis; Doktorgradsavhandling, 2022-09-23)The Arctic experiences faster climate change than the global average. Feedback mechanisms between the atmosphere, cryosphere and the oceans amplify the warming, and intensify the water cycle. Arctic precipitation is projected to increase because of enhanced winter evaporation due to diminishing sea ice, increased poleward moisture transport in summer, and increased atmospheric moisture content in ... -
Late Quaternary glacier and sea-ice history of northern Wijdefjorden, Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-10)The deglaciation history and Holocene environmental evolution of northern Wijdefjorden, Svalbard, are reconstructed using sediment cores and acoustic data (multibeam swath bathymetry and sub‐bottom profiler data). Results reveal that the fjord mouth was deglaciated prior to 14.5±0.3 cal. ka BP and deglaciation occurred stepwise. Biomarker analyses show rapid variations in water temperature and sea ... -
Persistence of Holocene ice cap in northeast Svalbard aided by glacio-isostatic rebound
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-29)The deglaciation of the Svalbard-Barents Sea Ice Sheet was driven by relative sea-level rise, the incursion of North Atlantic waters around Spitsbergen, and increasing summer insolation. However, ice retreat was inter rupted by asynchronous re-advances that occurred into high relative seas, during a period associated with warm regional waters and elevated summer temperatures. Better understanding ... -
Postglacial relative sea level change and glacier activity in the early and late Holocene: Wahlenbergfjorden, Nordaustlandet, Svalbard
(Journal article; Peer reviewed, 2019-05-01)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 radiocarbon dating of the cores show that Kløverbladvatna ...
