| 1. |
- Messias, M. J, et al.
(författare)
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The Greenland Sea tracer experiment 1996–2002: Horizontal mixing and transport of Greenland Sea Intermediate Water
- 2008
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Ingår i: Progress In Oceanography. - : Elsevier BV. - 0079-6611. ; 78:1, s. 85-105
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Tidskriftsartikel (refereegranskat)abstract
- In summer 1996, a tracer release experiment using sulphur hexafluoride (SF6) was launched in the intermediate-depth waters of the central Greenland Sea (GS), to study the mixing and ventilation processes in the region and its role in the northern limb of the Atlantic overturning circulation. Here we describe the hydrographic context of the experiment, the methods adopted and the results from the monitoring of the horizontal tracer spread for the 1996–2002 period documented by 10 shipboard surveys. The tracer marked “Greenland Sea Arctic Intermediate Water” (GSAIW). This was redistributed in the gyre by variable winter convection penetrating only to mid-depths, reaching at most 1800 m depth during the strongest event observed in 2002. For the first 18 months, the tracer remained mainly in the Greenland Sea. Vigorous horizontal mixing within the Greenland Sea gyre and a tight circulation of the gyre interacting slowly with the other basins under strong topographic influences were identified. We use the tracer distributions to derive the horizontal shear at the scale of the Greenland Sea gyre, and rates of horizontal mixing at 10 and 300 km scales. Mixing rates at small scale are high, several times those observed at comparable depths at lower latitudes. Horizontal stirring at the sub-gyre scale is mediated by numerous and vigorous eddies. Evidence obtained during the tracer release suggests that these play an important role in mixing water masses to form the intermediate waters of the central Greenland Sea. By year two, the tracer had entered the surrounding current systems at intermediate depths and small concentrations were in proximity to the overflows into the North Atlantic. After 3 years, the tracer had spread over the Nordic Seas basins. Finally by year six, an intensive large survey provided an overall synoptic documentation of the spreading of the tagged GSAIW in the Nordic Seas. A circulation scheme of the tagged water originating from the centre of the GS is deduced from the horizontal spread of the tracer. We present this circulation and evaluate the transport budgets of the tracer between the GS and the surroundings basins. The overall residence time for the tagged GSAIW in the Greenland Sea was about 2.5 years. We infer an export of intermediate water of GSAIW from the GS of 1 to 1.85 Sv (1 Sv = 106 m3 s−1) for the period from September 1998 to June 2002 based on the evolution of the amount of tracer leaving the GS gyre. There is strong exchange between the Greenland Sea and Arctic Ocean via Fram Strait, but the contribution of the Greenland Sea to the Denmark Strait and Iceland Scotland overflows is modest, probably not exceeding 6% during the period under study.
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| 2. |
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| 3. |
- Nash, David, et al.
(författare)
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Profile of the oral healthcare team in countries with emerging economies
- 2008
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Ingår i: European journal of dental education. - : Wiley. - 1396-5883 .- 1600-0579. ; 12:Suppl. 1, s. 111-119
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Health is a critical dimension of human well-being and flourishing, and oral health is an integral component of health: one is not healthy without oral health. Significant barriers exist to ensuring the world's people receive basic healthcare, including oral healthcare. Amongst these are poverty, ignorance, inadequate financial resources and lack of adequate numbers of educated and trained (oral) healthcare workers. Emerging economies are encouraged to develop a national strategic plan for oral health. International organizations have developed goals for oral health that can be referenced and adapted by emerging economies as they seek to formulate specific objectives for their countries. Demographic data that assess the nature and extent of oral diseases in a country are essential to sound planning and the development of an oral healthcare system that is relevant, effective and economically viable. Prevention should be emphasized and priority consideration be given to oral healthcare for children. The types and numbers of members of the oral healthcare team (workforce) will vary from country to country depending on the system developed. Potential members of the workforce include: generalist dentists, specialist dentists, dental therapists, dental hygienists, denturists, expanded function dental assistants (dental nurses) and community oral health workers/aides. Competences for dentists, and other members of the team, should be developed to ensure quality care and developed economies should cooperate with emerging economies. The development, by more advanced economies, of digital, virtual curricula, which could be used by emerging economies for educating and training members of the oral healthcare team, should be an important initiative. The International Federation of Dental Educators and Associations (IFDEA) should lead in such an effort.
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| 4. |
- Olsen, Are, 1972, et al.
(författare)
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Overview of the Nordic Seas CARINA data and salinity measurements
- 2009
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Ingår i: Earth System Science Data Discussions. - 1866-3591. ; 2, s. 1-25
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Tidskriftsartikel (refereegranskat)abstract
- Water column data of carbon and carbon relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruises in the Arctic, Atlantic, and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon IN the Atlantic). The data have been subject to rigorous quality control (QC) in order to ensure highest possible quality and consistency. The data for most of the parameters included were examined in order to quantify systematic biases in the reported values, i.e. secondary quality control. Significant biases have been corrected for in the data products, i.e. the three merged files with measured, calculated and interpolated values for each of the three CARINA regions; the Arctic Mediterranean Seas (AMS), the Atlantic (ATL) and the Southern Ocean (SO). With the adjustments the CARINA database is consistent both internally as well as with GLODAP (Key et al., 2004) and is suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation. The Arctic Mediterranean Seas includes the Arctic Ocean and the Nordic Seas, and the quality control was carried out separately in these two areas. This contribution provides an overview of the CARINA data from the Nordic Seas and summarises the findings of the QC of the salinity data. One cruise had salinity data that were of questionable quality, and these have been removed from the data product. An evaluation of the consistency of the quality controlled salinity data suggests that they are consistent to at least 0.05.
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| 5. |
- Reitzel, Kasper, et al.
(författare)
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Characterization of phosphorus in sequential extracts from lake sediments using P-31 nuclear magnetic resonance spectroscopy
- 2006
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - Univ So Denmark, Inst Biol, DK-5230 Odense M, Denmark. Univ Uppsala, Dept Analyt Chem, S-75124 Uppsala, Sweden. Univ Uppsala, Dept Organ Chem, S-75124 Uppsala, Sweden. Uppsala Univ, Dept Ecol & Evolut, EBC, S-75236 Uppsala, Sweden.. - 0706-652X .- 1205-7533. ; 63:8, s. 1686-1699
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Tidskriftsartikel (refereegranskat)abstract
- Phosphorus (P) compounds in three different lake surface sediments were extracted by sequential P extraction and identified by P-31 nuclear magnetic resonance (P-31 NMR) spectroscopy. The extraction procedure primarily discriminates between inorganic P-binding sites but most extraction steps also contained P not reacting (nrP) with the molybdenum complex during P analyses. In all three lakes, the nrP dominated in the NaOH extracts. Nonreactive P from the dystrophic lake was dominated by potentially recalcitrant P groups such as orthophosphate monoesters, while the nrP in the two more productive lakes also contained polyphosphates, pyrophosphate, and organic P groups such as P lipids and DNA-P that may be important in remineralization and recycling to the water column. In addition, polyphosphates showed substantial dynamics in settling seston. The Humic-P pools (P associated with humic acids) showed strong signals of orthophosphate monoesters in all three lakes, which supported the assumption that P-containing humic compounds are indeed recovered in this fraction, although other organic P forms are also present. Thus, in addition to expanding the understanding of which organic P forms that are present in lake sediments, the P-31 NMR technique also demonstrated that the chemical extraction procedure may provide some quantification of recalcitrant versus labile organic P forms.
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