Swedish Polar Research Secretariat
Not a member yet
76 research outputs found
Sort by
GEOEO North of Greenland 2024 : Expedition Report
No full textThis cruise report describes the background of the GEOEO – North of Greenland 2024 Expedition, logistical operations, data collection methods, and presents the acquired data
Geoengineering Symposium : Science Fiction or Possible Element for a Sustainable Environmental and Climate Future?
No full textGeoengineering represents a set of large-scale technological interventions aimed at mitigating climate change by modifying Earth's natural systems. This report summarizes discussions from the Geoengineering Symposium held in Luleå, Sweden, in collaboration with the Swedish Foundation for Strategic Research and other key institutions. The symposium explored two primary geoengineering approaches: solar radiation management (SRM) and carbon dioxide removal (CDR). Experts assessed the feasibility, potential benefits, and risks associated with these technologies, emphasizing the uncertainties related to regional climate effects, governance challenges, and ethical concerns. Key discussions also addressed the role of international governance, public perception, and the risk of moral hazard in geoengineering deployment. The symposium concluded that while geoengineering should not replace emissions reduction efforts, it may serve as an emergency measure or complement traditional mitigation strategies. Further scientific research, climate modeling, and inclusive policymaking are crucial to evaluating the future role of geoengineering in climate action
Förslag till forskningsstrategi för Antarktis : en integrerad ansats för svensk vetenskap
No full textDen 30 april 2024 levererade Polarforskningssekretariatet ett förslag på forskningsstrategi för Antarktis på uppdrag av utbildningsdepartementet. Förslaget är utarbetat av Polarforskningssekretariatet i samarbete med Center for the Arctic and Antarctic (CAA) vid Luleå tekniska universitet. Målsättningen är att forskningsstrategin ska höja Sveriges ambitionsnivå som aktiv forskningsnation i Antarktis och Södra ishavet, genom att stärka den pågående forskningen samt initiera nya samarbeten och aktiviteter
Quantifying earthworm soil ingestion from changes in vertical bulk density profiles
No full textSoil mixing by earthworms can have a large impact on the fate of nutrients and pollutants and on the soil's ability to sequester carbon. Nevertheless, methods to quantify earthworm ingestion and egestion under field conditions are largely lacking. Soils of the Fennoscandian tundra offer a special possibility for such quantifications, as these soils commonly lack burrowing macrofauna and exhibit a well-defined O horizon with low bulk density on top of a mineral soil with higher density. Since ingestion-egestion mixes the two soil layers, the temporal changes in the bulk density profile of such soils may be useful for estimating field ingestion rates. In this study, we applied a model for earthworm burrowing through soil ingestion to observed changes in soil densities occurring in a mesocosm experiment carried out in the arctic during four summers with intact soil. The earthworms present in the mesocosms were Aporrectodea trapezoides, Aporrectodea tuberculata, Aporrectodea rosea, Lumbricus rubellus and Lumbricus Terrestris (fourth season only). We show that changes in soil density profiles can indeed be used to infer earthworm ingestion rates that are realistic in comparison to literature values. Although uncertainties in parameter values were sometimes large, the results from this study suggest that soil turnover rates and endogeic earthworm soil ingestion rates in tundra heath and meadow soils may be as high as those reported for temperate conditions. Such large ingestion rates can explain observed large morphological changes in arctic soils where dispersing earthworms have resulted in complete inmixing of the organic layer into the mineral soil. Our approach is applicable to soil profiles with marked vertical differences in bulk density such as the soils of the Fennoscandian tundra where earthworms are currently dispersing into new areas and to layered repacked soil samples that are incubated in the field
Higher vascular plant abundance associated with decreased ecosystem respiration after 20 years of warming in the forest–tundra ecotone
No full textThe on-going climate warming is promoting shrub abundance in high latitudes, but the effect of this phenomenon on ecosystem functioning is expected to depend on whether deciduous or evergreen species increase in response to warming. To explore effects of long-term warming on shrubs and further on ecosystem functioning, we analysed vegetation and ecosystem CO2 exchange after 20 years of warming in the forest–tundra ecotone in subarctic Sweden. A previous study conducted 9 years earlier had found increased evergreen Empetrum nigrum ssp. hermaphroditum in the forest and increased deciduous Betula nana in the tundra. Following current understanding, we expected continued increase in shrub abundance that would be stronger in tundra than in forest. We expected warming to increase ecosystem respiration (Re) and gross primary productivity (GPP), with a greater increase in Re in tundra due to increased deciduous shrub abundance, leading to a less negative net ecosystem exchange and reduced ecosystem C sink strength. As predicted, vascular plant abundances were higher in the warmed plots with a stronger response in tundra than in forest. However, whereas B. nana had increased in abundance since the last survey, E. hermaphroditum abundance had declined due to several moth and rodent outbreaks during the past decade. In contrast to predictions, Re was significantly lower in the warmed plots irrespective of habitat, and GPP increased marginally only in the forest. The lower Re and a higher GPP under warming in the forest together led to increased net C sink. Re was negatively associated with the total vascular plant abundance. Our results highlight the importance of disturbance regimes for vegetation responses to warming. Climate warming may promote species with both a high capacity to grow under warmer conditions and a resilience towards herbivore outbreaks. Negative correlation between Re and total vascular plant abundance further indicate that the indirect impacts of increased plants on soil microclimate may become increasingly important for ecosystem CO2 exchange in the long run, which adds to the different mechanisms that link warming and CO2 fluxes in northern ecosystems. Read the free Plain Language Summary for this article on the Journal blog
Small molecules dominate organic phosphorus in NaOH-EDTA extracts of soils as determined by 31P NMR
No full textUnderstanding the composition of organic phosphorus (P) in soils is relevant to various disciplines, from agricultural sciences to ecology. Despite past efforts, the precise nature of soil organic P remains an enigma, especially that of the orthophosphate monoesters, which dominate 31P NMR spectra of NaOH-EDTA extracts of soils worldwide. The monoester region often exhibits an unidentified, broad background believed to represent high molecular weight (MW) P. We investigated this monoester background using 1D 31P NMR and 2D 1H[sbnd]31P NMR, as well as 31P transverse relaxation (T2) measurements to calculate its intrinsic linewidth and relate it to MW. Analyzing seven soils from different ecosystems, we observed linewidths of 0.5 to 3 Hz for resolved monoester signals and the background, indicating that it consists of many, possibly >100, sharp signals associated with small (<1.5 kDa) organic P molecules. This result was further supported by 2D 1H[sbnd]31P NMR spectra revealing signals not resolved in the 1D spectra. Our findings align with 31P NMR studies detecting background signals in soil-free samples and modern evidence that alkali-soluble soil organic matter consists of self-assemblies of small organic compounds mimicking large molecules
Genomic variation in montane bumblebees in Scandinavia : High levels of intraspecific diversity despite population vulnerability
No full textPopulations of many bumblebee species are declining, with distributions shifting northwards to track suitable climates. Climate change is considered a major contributing factor. Arctic species are particularly vulnerable as they cannot shift further north, making assessment of their population viability important. Analysis of levels of whole-genome variation is a powerful way to analyse population declines and fragmentation. Here, we use genome sequencing to analyse genetic variation in seven species of bumblebee from the Scandinavian mountains, including two classified as vulnerable. We sequenced 333 samples from across the ranges of these species in Sweden. Estimates of effective population size (NE) vary from ~55,000 for species with restricted high alpine distributions to 220,000 for more widespread species. Population fragmentation is generally very low or undetectable over large distances in the mountains, suggesting an absence of barriers to gene flow. The relatively high NE and low population structure indicate that none of the species are at immediate risk of negative genetic effects caused by high levels of genetic drift. However, reconstruction of historical fluctuations in NE indicates that the arctic specialist species Bombus hyperboreus has experienced population declines since the last ice age and we detected one highly inbred diploid male of this species close to the southern limit of its range, potentially indicating elevated genetic load. Although the levels of genetic variation in montane bumblebee populations are currently relatively high, their ranges are predicted to shrink drastically due to the effects of climate change and monitoring is essential to detect future population declines
Lufttemperaturens, vindens och snödjupets inverkan på utveckling av laviner i Abisko/Riksgränsen under 2021
No full textDet huvudsakliga syftet med denna studie är att studera möjligheten att koppla rapporterade väderdata till antalet rapporterade laviner inom samma område och undersöka i vilken utsträckning rapporterad temperatur, snödjup och vindhastighet påverkar utvecklingen av laviner. I arbetet studeras väderdata kopplat till lavinrapportering inom området Abisko/Riksgränsen. Studien fokuserar på spontant utlösta laviner, det vill säga laviner som utlösts av naturliga väderfenomen utan mänsklig påverkan.Studien bygger på väderdata från endast en väderstation, Katterjåkk, som således får representera hela lavinprognosområdet Abisko/Riksgränsen. Trots att vädret kan uppvisa lokala variationer inom det valda området, tyder resultaten på att det finns ett klart samband mellan å ena sidan väderförhållandena (förändringar i snödjup, vindstyrka och temperatur) och antalet spontant utlösta laviner.Studien visar att väderdata kan användas för att undersöka lavinutveckling i området, och att mer eller mindre ökande snödjup i kombination med vindhastighet verkar vara den huvudsakliga orsaken bakom lavinerna. Många laviner under senare vår verkar också kunna initieras av snabba temperaturförändringar
Expedition Report SWEDARCTIC : Synoptic Arctic Survey 2021 with icebreaker Oden
No full textThe SAS-Oden 2021 expedition (SO21) with icebreaker Oden (IB Oden) is the Swedish contribution to the international scientist-driven initiative ”Synoptic Arctic Survey” (SAS). SAS will collect primary ecosystem data in the Arctic Ocean in 2020-2022 from both icebreaking and non-icebreaking research vessels. The goal of SAS is to generate a comprehensive dataset that allows for an improved characterisation of the Arctic Ocean with respect to its (1) physical oceanography, (2) marine ecosystems and (3) carbon cycle. The complete SAS dataset will provide a unique baseline that will allow for tracking climate change and its impacts as they unfold in the Arctic region over the coming years, decades and centuries.The marine ecosystems of the Arctic Ocean are experiencing rapid change. This includes the Large Marine Ecosystem (LME) in the middle, the Central Arctic Ocean (CAO) as defined by the Arctic Council, i.e., the deep basins and ridges around the North Pole that until recently were permanently covered by 2-3 m thick sea ice. In the past two decades, up to 40% of the 3.3. km2 large CAO has been ice-free for a short period in September. This reduction in sea-ice coverage of the CAO is transforming a basically inaccessible marine ecosystem into a new type of ecosystem with seasonal changes in sea ice cover. The CAO is a poorly investigated corner of the World Ocean, especially from an ecosystem perspective, i.e., integrating biological, chemical and physical data. Since the SAS-Oden 2021 expedition was designed as a joint ecosystem study with data collection in an integrated way, the results from this expedition will contribute significantly to the knowledge on ecological baselines of the CAO as well as on ecosystem change. The latter is achieved by comparing areas along the expedition route with different types of sea ice, including both steady and heavily melting multi-year ice.The SAS-Oden 2021 expedition reached further west on the Greenland shelf than any other research expedition has ever done before. Closest was the geological Lomrog III expedition with IB Oden in 2007, but then ice-breaking assistance was needed from the accompanying Russian atomic-driven icebreaker “50 Let Pobedy” to get this far west. Between SO21 stations 42 and 53 (Figure 1.1), the SAS-Oden 2021 expedition was in a completely unexplored area. This is, a.o., illustrated by the fact that the seabed map of this area now needs revision; in one place we recorded 900 m depth instead of 300 m on the existing map while in another place it was 1200 m shallower than indicated on the map. We now have the first on-site measurements of physical environment, carbon cycle and nutrients combined with prokaryote, photosynthetic, zooplankton and fish production and diversity, as well as many other ecosystem parameters, from the area between SO21 stations 30 and 53. The SO21 omics samples form the basis for a unique biodiversity dataset, covering water column, ice habitats, and sediments. These samples include the metagenomes and metatranscriptomes of viruses, archaea, bacteria, protists, and eDNA of multicellular organisms such as zooplankton, fish, squid and mammals.The SO21 joint ecosystem study was carried out by 38 scientists assisted by 15 persons from the Swedish Polar Research Secretariat (SPRS) and the 22-person IB Oden crew. Altogether, the expedition visited 60 sampling stations, of which 36 were ship stations and 24 were ice stations accessed by helicopter (Figure 1.1, Table 1.1). Since the main research project on board (EFICA) included nine “EFICA Master Stations”, lasting for on average 33 hours during which the ship was lying still, there were ample possibilities for ice work from the ship as well.SAS 2021 - Meteorologiska och oceanografiska data, samt skeppsdata, insamlade på isbrytaren Oden. Svensk nationell datatjänst. Version 1. https://doi.org/10.48515/0v1w-8958</p
Do bumblebees patition an elevational gradient by body size?
No full textAs the climate warms, Arctic bumblebee species face the loss of habitat and must deal with increased competition from southern species tracking their thermal and habitat niches north, for example Bombus terrestris. Previous studies demonstrate that bumblebees follow Bergmann’s rule, i.e., larger body sizes at higher latitudes, despite bumblebees not being considered truly ectothermic, as they can generate heat through muscular activity (i.e., beating their wings). This study seeks to confirm and understand the relationship between body size and temperature using an elevational gradient as a proxy for climate. In this study, I examined 13 plots (420-1164 m.a.s.l.) set along the 3.4 km transect up the slope of Mt. Nuolja in Abisko National Park, Sweden. For body size, I chose to use the commonly accepted proxy distance between the base of the wings (i.e., intertegular distance). For temperature, I chose the mean temperature at time of visitation. Results show that climate is a significant explanatory variable for bumblebee body size, with an overall increasing body size with increasing elevation (i.e., colder climate), although most of the variance is explained by caste, i.e., queens having a larger body size than workers. Body size also shows some correlation with day of capture, which can be explained by changes in environmental conditions (e.g., temperature, flowering plant species) during the growing season experienced by the different emerging times for the castes. Given that caste was the most useful explanatory variable for body size, future studies could look at a larger environmental gradient, for example, by sampling at multiple locations along the entire Scandes mountain range to see if the effects found are localized. Further, specific habitat and specific traits of preferred plants may also help to elucidate body-size differences between species and castes. For example, many bumblebee species’ castes emerge at a specific time of year when only certain flowering plant species in specific habitats are available. This important research would also help to illuminate whether bumblebees and the species of plants they pollinate remain synchronous as climate warming accelerates. Nevertheless, my results show an overall positive relationship between bumblebee body size and elevation, indicating that a warming climate will result in reduced body sizes among bumble bee species. Future studies will have to investigate what consequences this will have for Arctic bumblebee populations – and for the plants that rely on bumblebee visits for their pollination