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Data repository for: Relative sea-level trends in southern Norway during the last millennium
No full textThis dataset contains all supplementary data for: Relative sea-level trends in southern Norway during the last millennium.
It is organized as follows:
- 01 - Tidal data October to December 2023
- 02 - Stable isotopes of surface transect and TV-1
- 03 - Salinity measurements of surface transect
- 04 - Grain size TV-1
- 05 - LOI and DBD TV-2
- 06 - XRF and PCA TV-1
- 07 - Chronology TV-1
- 08 - Accretion rates TV-1
- 09 - All data vs modelled age
- 10 - QAnalySeries inputs and results
- 11 - Quantitative comparison data LOI and PC2Geological reconstructions of relative sea-level (RSL) from southern Norway show falling RSL during the last 7000 cal. a BP, but tide gauge measurements document a slow RSL rise since at least 1960 CE. With an age gap of c. 1400 years between the youngest geologically-reconstructed sea-level index point (SLIP) and the installation of the Tregde tide gauge in southernmost Norway, the exact nature and timing of the onset of RSL rise in southern Norway remains unknown. To fill this gap, we collected peat cores from a salt marsh to reconstruct RSL trends over the past 1000 years using a multiproxy approach, including 210Pb and 14C dating, grain-size analysis, loss-on-ignition (LOI), geochemistry (stable carbon isotopes, carbon/nitrogen ratios and XRF) and diatoms. Our data suggest decreasing tidal current strength and salinity over most of the last millennium, suggesting falling RSL. Sediment geochemistry also appears to vary with wetter and drier climatic periods. An increase in marine-brackish diatoms in combination with an acceleration in sedimentation rates after 1930 CE (1899-1954 CE) suggest that the onset of RSL rise began around this time in southernmost Norway. While most of the proxy data appear to have delayed sensitivity to RSL changes and may be linked to other causal processes, they, nonetheless, provide valuable insight into the environmental response of high-latitude temperate salt marshes to slow rates of RSL change
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Shell deposition and storminess
No full textSom en av konsekvensene fra menneskeskapte klimaendringer, stiger det gjennomsnittlige havnivået i en økende skala. Som en del av QUANTSEA, et større prosjekt med mål om å rekonstruere nylige havnivåendringer i Norge, ser denne oppgaven nærmere på historien av storm og stormflo. I forbindelse med dette prosjektet ble det tatt to sedimentkjerner fra en mikrotidal saltmyr i sør-vestlige Norge. Det ble funnet flere lag med fragmenterte skjell som ble mistenkt for å være knyttet til stormlag deponert fra større stormer. Formålet med denne masteroppgaven er å undersøke om det eksisterer noen konsistente geokjemiske signaturer knyttet til disse fragmenterte skjell-lagene, og hvordan de skiller seg fra resten av stratigrafien i kjernen, som antas å representere de gjennomsnittlige forholdene i Saltatjørna. For å svare på dette ble kjernene skannet med røntgenfluorescens (XRF) og dataen ble deretter behandlet og analysert. I tillegg ble det gjennomført loss-on-ignition (LOI) analyse på deler av kjerneprøven.
Resultatene viser en trend i de analytiske konseptene, der nivåene i de elementære representantene Ca og Sr generelt øker over skjell-lagene. Samtidig synker de andre elementære representantene som ble brukt, Fe, Zr, Cl og Br. LOI analysene viste også mye mindre organisk innhold over skjell-lagene. Sammen med andre observasjoner, CT skanning, historiske fotografier, og målinger av «sill» og «wrack line» konkluderer oppgaven med at det er en korrelasjon. Nivåene av Sr og Ca indikerer marin påvirkning, mens den synkende verdien av Fe er en indikasjon for synkende input av terrigene materialer. Kombinert med kunnskap om tidevann-nivået rundt studieområdet, konkluderes det med at denne marine påvirkningen ikke er et resultat av regelmessig tidevann, men helle sjeldnere, større stormfloer.As one of the consequences of human-caused climate change, average sea levels are rising at an increasing rate. As part of QUANTSEA, a larger project that aims to reconstruct more recent sea level changes in Norway, the focus of this thesis is to look into records of storms and storm surges. For the project, two cores were sampled from a microtidal saltmarsh in south-western Norway. The several shell layers observed in the cores were suspected to be connected to storm layers deposited from bigger storms. The goal of the thesis is to research whether there are any consistent geochemical signatures associated with these distinct fragmented shell layers, and how they differentiate from the rest of the core stratigraphy, which is presumed to represents average conditions in Saltatjørna. In order to answer this, the cores were scanned with X-ray fluorescence (XRF), and the data was then transformed and analyzed. Some samples also underwent a loss-on-ignition (LOI) analysis.
The results show a trend in the analytical concepts, were the levels of the elemental proxies Ca and Sr generally increased over the shell layers, while the other proxies used, Fe, Zr, Cl and Br, all decreased. The LOI also showed much less organic content over the shell layers. Together with other observations, such as CT scans, historical photographs, and measurements of the sill elevation and wrack line, the thesis concludes that there is a correlation. The Sr and Ca levels indicate marine influence, whereas the decreasing Fe is a proxy for decreasing terrigenous materials. Combined with knowledge of the tidal range around the study area, it is concluded that this marine influence is not the result of regular tides, but rather rarer, larger storm surges
Assessing the influence of relative sea level rise on carbon storage and sedimentation dynamics in an arctic salt marsh
Get PDFBasert på fremtidige prognoser, kan den høyeste prosjekterte havnivåstigningen, som er RCP8.5, nå ~6 mm/år innen 2100 (Simpson et al., 2015). Norge opplever fortsatt landheving på grunn av glasial isostasi, men i kystområdene er landhevingen lavere siden disse områdene hadde mindre isdekke, noe som igjen gjør at havnivåstigningen har større innvirkning på disse områdene i Norge (Framtidig havnivå langs Norskekysten, 2024). Denne oppgaven har som mål å fylle kunnskapshull om arktiske saltmyrer. Det primære målet med oppgaven er å se på hvilke prosesser som driver endringer i organisk materiale i sedimentene i arktiske saltmyrer, og hvordan disse endringene påvirker saltmyrene sin motstandsdyktighet på grunn av havnivåstigningen, samtidig som å se på hvordan havnivåstigningen vil påvirke karbonlagringen og sedimentasjonsrater i en liten arktisk saltmyr nær Kongsfjorden, Norge.
Kjerner samlet fra Kongsfjorden saltmyr er analysert for δ13C, C/N, kornstørrelse, totalt organisk karbon (TOC), og glødetapsanalyse (LOI) for å se på sediment akkumuleringen og avsetningen av organisk materiale over tid. Sedimentkjernene illustrerer endringer, men de reflekterer ikke den havnivåstigningen vi opplever nå. Imidlertid indikerer de at saltmyren har gjennomgått en lignende forandring tidligere som den vi opplever med havnivåstigning nå. Med havnivåstigning forventes det en økning i akkumulering av organisk materiale. Sedimentasjons- og karbonakkumuleringsratene indikerer en lav akkumulerings rate, men tar ikke hensyn til andre faktorer som kan påvirke akkumuleringen av organisk materiale. I kjernene kan vi tydelig se høye verdier av organisk materiale i den øverste delen av kjernene, noe som indikerer gode forhold for akkumulering, sekvestrering og bevaring av organisk materiale. Sammen med δ13C, C/N, TOC, LOI, og kornstørrelse ser kjernene ut til å ha motstått endringer i miljø, forårsaket av enten havnivå, stormflo, endringer i tidevannsregimet og havis, noe som gjør dem verdifulle som motstandsdyktige kystøkosystem mot klimaendringer. De nåværende sedimentasjonsratene som er observert, er utilstrekkelige til å holde tritt med den nåværende havnivåstigningen, men med havnivåstigning vil vi også oppleve en økning i sedimentasjonsraten. Saltmyren viser dynamiske endringer på tidligere havnivåendringer gjennom økt sedimentasjon og akkumulering av organisk materiale, som er avgjørende for stabiliteten til saltmyr systemet. Disse funnene understreker viktigheten av å begrense klimaendringene og forvalte kystøkosystemer for å beskytte disse verdifulle habitatene.Based on future projections, the highest projected RSLR, which follows RCP8.5, might reach ~6 mm/yr by 2100 (Simpson et al., 2015). Norway are still experiencing uplift due to GIA, however in coastal areas the rate of uplift are lower since these areas had less ice covering the area, which again causes the RSLR to have a greater impact on these areas in Norway (Framtidig havnivå langs Norskekysten, 2024). This thesis aims to fill in gaps in knowledge on arctic salt marshes. The primary aim of the thesis is to look at what processes drives shifts in organic matter within arctic salt marsh sediments, and how these changes affect the resilience of salt marshes due to RSLR, and to determine how the RSLR will impact the carbon storage and sedimentation rates of a small arctic salt marsh near Kongsfjorden, Norway.
Cores collected from the Kongsfjorden salt marsh are analysed for δ13C, C/N, grain size, total organic carbon (TOC), and loss on ignition (LOI) to interpret sediment accumulation and organic matter deposition over time. The sediment cores illustrate changes, but it does not reflect the RSLR we are experiencing now. However, it does indicate that the salt marsh has been through a similar transition that we are experiencing now with RSLR in the past. With RSLR it is expected that we get an increase in the accumulation of organic matter. The sedimentation and CAR rates indicate a low rate of accumulation but does not take into account other factors that might influence the accumulation of organic matter. In the cores, we can clearly see high values of organic matter in the uppermost part of the cores, which indicate good conditions for organic matter accumulation, sequestration, and preservation. Alongside with the δ13C, C/N, TOC, LOI, and grain size the cores seems to have withstand changes in the environmental conditions, caused by either RSL, storm surges, changes in the tidal regime and sea-ice push, making them hold value as resilience to environmental changes. The current sedimentation rates observed are insufficient to keep pace with the current RSLR, however with RSLR we will also experience an increase in the sedimentation rate. The marsh shows dynamic responses to past sea level changes through increased sedimentation and organic matter accumulation, which are crucial for the stability of the marsh system. These findings highlight the importance of mitigating climate change and managing coastal ecosystems to protect these valuable habitats
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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