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Organic carbon deposition flux on the North Chukchi Sea shelf based on 210Pb radioactivity dating
Get PDFDeposition of organic carbon forms the final net effect of the ocean carbon sink at a certain time scale. Organic carbon deposition on the Arctic shelves plays a particularly important role in the global carbon cycle because of the broad shelf area and rich nutrient concentration. To determine the organic carbon deposition flux at the northern margin of the Chukchi Sea shelf, the 210Pb dating method was used to analyze the age and deposition rate of sediment samples from station R17 of the third Chinese National Arctic Research Expedition. The results showed that the deposition rate was 0.6 mm∙a-1, the apparent deposition mass flux was 0.72 kg∙m-2∙a-1, and the organic carbon deposition flux was 517 mmol C∙m-2∙a-1. It was estimated that at least 16% of the export organic carbon flux out of the euphotic zone was transferred and chronically buried into the sediment, a value which was much higher than the average ratio (~10%) for low- to mid-latitude regions, indicating a highly effective carbon sink at the northern margin of the Chukchi Sea shelf. With the decrease of sea ice coverage caused by warming in the Arctic Ocean, it could be inferred that the Arctic shelves will play an increasingly important role in the global carbon cycle
Syktyvkar State University
No full textSyktyvkar State University is the principal educational institution of Syktyvkar, the capital city of Komi Republic, being the federal subject of Russia. The University was founded in 1972 and currently has close to 5000 full time students and almost 300 faculty members
The Shipping Portlet
No full textThe Shipping Portlet is a comprehensive gateway to Arctic Shipping most prominent issues. Establishing the network connection between public and private sector, gives the detailed overview through outstanding marine and air traffic matters, including benchmarking and baseline assessment of marine ports and airports infrastructure. Compatible, interactive mapping system, illustrates gaps in knowledge and capacity
Alaska Center for Energy and Power
No full texthe Alaska Center for Energy and Power (ACEP) based at the University of Alaska is dedicated to applied energy research and testing focused on lowering the cost of energy throughout Alaska and developing economic opportunities for the State, its residents, and its industries
Ministry of Sport, Tourism and Youth Policy of the Russian Federation
No full textThe Ministry of Sport, Tourism and Youth Policy is a federal agency under the executive branch responsible for drafting and implementing national policy and legal regulation with regard to physical fitness, sports, tourism and youth policy
WWF: 20 years in the Arctic
No full textA publications celebrating World Wildlife Fund´s 20th anniversary in Arctic issues. Highlights from the Global WWF Arctic Programme
Seasonal and inter-annual variations of the primary types of the Arctic sea-ice drifting patterns
Get PDFMonthly mean sea ice motion vectors and monthly mean sea level pressure (SLP) for the period of 1979—2006 are investigated to understand the spatial and temporal changes of Arctic sea-ice drift. According to the distinct differences in monthly mean ice velocity field as well as in the distribution of SLP, there are four primary types in the Arctic Ocean: Beaufort Gyre+Transpolar Drift, Anticyclonic Drift, Cyclonic Drift and Double Gyre Drift. These four types account for 81% of the total, and reveal distinct seasonal variations. The Cyclonic Drift with a large-scale anticlockwise ice motion pattern trends to prevail in summer while the Anticyclonic Drift with an opposite pattern trends to prevail in winter and spring. The prevailing seasons for the Beaufort Gyre+Transpolar Drift are spring and autumn, while the Double Gyre Drift trends to prevail in winter, especially in February. The annual occurring times of the Anticyclonic Drift and the Cyclonic Drift are closely correlated with the yearly mean Arctic Oscillation (AO) index, with a correlation coefficient of -0.54 and 0.54 (both significant with the confident level of 99%), respectively. When the AO index stays in a high positive (negative) condition, the sea-ice motion in the Arctic Ocean demonstrates a more anticlockwise (clockwise) drifting pattern as a whole. When the AO index stays in a neutral condition, the sea-ice motion becomes much more complicated and more transitional types trend to take place
Anomalously low ozone of 1997 and 2011 Arctic spring: Monitoring results and analysis
Get PDFTotal ozone observations from the Total Ozone Unit (TOU) aboard the Chinese second generation polar orbiting meteorological satellite, Fengyun-3/A (FY-3/A), revealed that total column ozone over the Arctic declined rapidly from the beginning of March 2011. An extensive region of low column amount formed around mid March; monthly mean total column ozone in March 2011 was about 30% lower than the average observed during 1979—2010. Daily total column density of ozone near the center of low ozone area in mid March was less than 240 Dobson units, about half the total column ozone amount observed during the same period of the prior 10 years. We analyzed total column ozone data from different satellites during 1979—2011. Results show that the Arctic depletion of ozone in spring 2011 was initiated by the cold polar vortex in the lower stratosphere. The March mean total ozone over the Arctic has shown a decreasing trend over the past 32 years, and its variation is strongly correlated with the polar vortex. A similar low ozone process of spring 1997 was compared to that of 2011, but daily variations of total ozone in March over the Northern Hemisphere in 1997 and 2011 have different patterns
Pollen morphology of selected tundra plants from the high Arctic of Ny-Ålesund, Svalbard
Get PDFDocumenting morphological features of modern pollen is fundamental for the identification of fossil pollen, which will assist researchers to reconstruct the vegetation and climate of a particular geologic period. This paper presents the pollen morphology of 20 species of tundra plants from the high Arctic of Ny-Ålesund, Svalbard, using light and scanning electron microscopy. The plants used in this study belong to 12 families: Brassicaceae, Caryophyllaceae, Cyperaceae, Ericaceae, Juncaceae, Papaveraceae, Poaceae, Polygonaceae, Ranunculaceae, Rosaceae, Salicaceae, and Scrophulariaceae. Pollen grain shapes included: spheroidal, subprolate, and prolate. Variable apertural patterns ranged from 2-syncolpate, 3-colpate, 3-(-4)-colpate, 3-(-5)-colpate, 3-colporate, 5-poroid, ulcerate, ulcus to pantoporate. Exine ornamentations comprised psilate, striate-perforate, reticulate, microechinate, microechinate-perforate, scabrate, granulate, and granulate-perforate. This study provided a useful reference for comparative studies of fossil pollen and for the reconstruction of paleovegetation and paleoclimate in Svalbard region of Arctic
The distribution and demography of Euphausia superba in Prydz Bay during the austral summer 2002
Get PDFThis study documents the horizontal distribution and demography of Antarctic krill (Euphausia superba Dana), collected using trawls, from the Prydz Bay region during January 2002. Euphausia superba (E. superba) was distributed primarily south of 64°S. The average density and biomass were estimated as 68.85 ind·(1 000 m-3) and 24.16 g wet weight·(1 000 m-3), respectively. Highest values were located in the open sea (depth > 3 000 m). Body length of E. superba ranged from 30 to 55 mm (N=1 758), with a mean length of 38.45±3.68 mm (SD). The overall sex ratio was approximately 1∶1, 47.6% females (41.9% sub-adults and 5.7% adults), 46.6% males (42.7% sub-adults and 3.9% adults), while 5.8% were juveniles. The population structure of E. superba exhibited geographical variation. At stations in the western part of the survey area populations had a high proportion of juveniles, a lower sexual maturity stage for males and small body size, while the opposite was found at stations in the eastern part. A latitudinal difference was found at stations along 70.5°E and 73°E transects: body length was small and the sex ratio was high in regions of high latitude, while the opposite occurred in areas of low latitude