| 1. |
- Parmentier, Frans Jan W, et al.
(författare)
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A synthesis of the arctic terrestrial and marine carbon cycles under pressure from a dwindling cryosphere
- 2017
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Ingår i: Ambio: a Journal of the Human Environment. - : Springer Science and Business Media LLC. - 0044-7447. ; 46, s. 53-69
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Tidskriftsartikel (refereegranskat)abstract
- The current downturn of the arctic cryosphere, such as the strong loss of sea ice, melting of ice sheets and glaciers, and permafrost thaw, affects the marine and terrestrial carbon cycles in numerous interconnected ways. Nonetheless, processes in the ocean and on land have been too often considered in isolation while it has become increasingly clear that the two environments are strongly connected: Sea ice decline is one of the main causes of the rapid warming of the Arctic, and the flow of carbon from rivers into the Arctic Ocean affects marine processes and the air–sea exchange of CO2. This review, therefore, provides an overview of the current state of knowledge of the arctic terrestrial and marine carbon cycle, connections in between, and how this complex system is affected by climate change and a declining cryosphere. Ultimately, better knowledge of biogeochemical processes combined with improved model representations of ocean–land interactions are essential to accurately predict the development of arctic ecosystems and associated climate feedbacks.
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| 2. |
- Pućko, Monika, et al.
(författare)
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Current use pesticide and legacy organochlorine pesticide dynamics at the ocean-sea ice-atmosphere interface in resolute passage, Canadian Arctic, during winter-summer transition
- 2017
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 580, s. 1460-1469
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Tidskriftsartikel (refereegranskat)abstract
- Here, we present the first detailed analysis of processes by which various current use pesticides (CUPs) and legacy organochlorine pesticides (OCPs) are concentrated in melt ponds that form on Arctic sea ice in the summer, when surface snow is melting and ice eventually breaks up. Four current use pesticides (dacthal, chlorpyrifos, trifluralin, and pentachloronitrobenzene) and one legacy organochlorine pesticide (α-hexachlorocyclohexane) were detected in ponds in Resolute Passage, Canadian Arctic, in 2012. Melt-pond concentrations changed over time as a function of gas exchange, precipitation, and dilution with melting sea ice. Observed increases in melt-pond concentrations for all detected pesticides were associated with precipitation events. Dacthal reached the highest concentration of all current use pesticides in ponds (95 ± 71 pg L− 1), a value exceeding measured concentrations in the under-ice (0 m) and 5 m seawater by > 10 and > 16 times, respectively. Drainage of dacthal-enriched pond water to the ocean during ice break-up provides an important ice-mediated annual delivery route, adding ~ 30% of inventory in the summer Mixed Layer (ML; 10 m) in the Resolute Passage, and a concentrating mechanism with potential implications for exposures to organisms such as ice algae, and phytoplankton.
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| 3. |
- Pućko, Monika, et al.
(författare)
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The delivery of organic contaminants to the Arctic food web : why sea ice matters
- 2015
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 506–507, s. 444-452
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Tidskriftsartikel (refereegranskat)abstract
- For decades sea ice has been perceived as a physical barrier for the loading of contaminants to the Arctic Ocean. We show that sea ice, in fact, facilitates the delivery of organic contaminants to the Arctic marine food web through processes that: 1) are independent of contaminant physical–chemical properties (e.g. 2–3-fold increase in exposure to brine-associated biota), and 2) depend on physical–chemical properties and, therefore, differentiate between contaminants (e.g. atmospheric loading of contaminants to melt ponds over the summer, and their subsequent leakage to the ocean). We estimate the concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in melt pond water in the Beaufort Sea, Canadian High Arctic, in 2008, at near-gas exchange equilibrium based on Henry's law constants (HLCs), air concentrations and exchange dynamics. CUPs currently present the highest risk of increased exposures through melt pond loading and drainage due to the high ratio of melt pond water to seawater concentration (Melt pond Enrichment Factor, MEF), which ranges from 2 for dacthal to 10 for endosulfan I. Melt pond contaminant enrichment can be perceived as a hypothetical ‘pump’ delivering contaminants from the atmosphere to the ocean under ice-covered conditions, with 2–10% of CUPs annually entering the Beaufort Sea via this input route compared to the standing stock in the Polar Mixed Layer of the ocean. The abovementioned processes are strongly favored in first-year ice compared to multi-year ice and, therefore, the dynamic balance between contaminant inventories and contaminant deposition to the surface ocean is being widely affected by the large-scale icescape transition taking place in the Arctic.
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| 4. |
- Rysgaard, Søren, et al.
(författare)
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A mobile observatory powered by sun and wind for near real time measurements of atmospheric, glacial, terrestrial, limnic and coastal oceanic conditions in remote off-grid areas
- 2022
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Ingår i: HardwareX. - : Elsevier BV. - 2468-0672. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Climate change is rapidly altering the Arctic environment. Although long-term environmental observations have been made at a few locations in the Arctic, the incomplete coverage from ground stations is a main limitation to observations in these remote areas. Here we present a wind and sun powered multi-purpose mobile observatory (ARC-MO) that enables near real time measurements of air, ice, land, rivers, and marine parameters in remote off-grid areas. Two test units were constructed and placed in Northeast Greenland where they have collected data from cabled and wireless instruments deployed in the environment since late summer 2021. The two units can communicate locally via WiFi (units placed 25 km apart) and transmit near-real time data globally over satellite. Data are streamed live and accessible from (https://gios.org). The cost of one mobile observatory unit is c. 304.000€. These test units demonstrate the possibility for integrative and automated environmental data collection in remote coastal areas and could serve as models for a proposed global observatory system.
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