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Dome Argus: Ideal site for deep ice drilling
Get PDFLocated on the centre of ice drainage range, the highest Dome Argus (Dome A) of East Antarctic Ice Sheet (EAIS), could be represented as an ideal site for deep ice cores drilling containing oldest paleo-climate records. To select a suitable drilling site for deep ice core, it needs gather all information pertaining to the local meteorology, ice sheet landforms, ice thickness, subglacial topography of bed rocks, ice velocity, internal structures of ice sheet, etc. Based on the International Partnerships in Ice Core Sciences (IPICS), we present recent achievement of glaciological research and its perspective at Dome A in this paper. We systematically discussed the merits and possible ventures of potential drilling sites around Dome A. Among all the candidates, we find that the Chinese Antarctic Kunlun Station is the best site for carrying out the first deep ice core drilling campaign. We emphasize and assess further the possibility to obtain a replicate core for studying dynamics and evolution of climate change
Composition and distribution of fish species collected during the fourth Chinese National Arctic Research Expedition in 2010
Get PDFThere are awareness and concerns caused by the decreasing sea ice coverage around the Arctic and Antarctic due to effects of climate change. Emphasis in this study was on rapid changes in Arctic sea ice coverage and its impacts on the marine ecology during the fourth Chinese National Arctic Research Expedition in 2010. Our purpose was to establish a baseline of Arctic fish compositions, and consequent effects of climate change on the fish community and biogeography. Fish specimens were collected using a multinet middle-water trawl, French-type beam trawl, otter trawl, and triangular bottom trawl. In total, 36 tows were carried out along the shelf of the Bering Sea, Bering Strait, and Chukchi Sea in the Arctic Ocean. In total, 41 fish species belonging to 14 families in 7 orders were collected during the expedition. Among them, the Scorpaeniformes, including 17 species, accounted for almost one third of the total number (34.8%), followed by 14 species of the Perciformes (27.0%), 5 species of the Pleuronectiformes(22.3%), and 2 species of the Gadiformes (15.4%). The top 6 most abundant species were Hippoglossoides robustus, Boregadus saida, Myoxocephalus scorpius, Lumpenus fabricii, Artediellus scaber, and Gymnocanthus tricuspis. Abundant species varied according to the different fishing methods; numbers of families and species recorded did not differ with the various fishing methods; species and abundances decreased with depth and latitude; and species extending over their known geographic ranges were observed during the expedition. Station information, species list, and color photographs of all fishes are provided
Influence of sea ice and sea surface temperature on the abundance of Antarctic krill in Area 48.2
Get PDFIn this paper we examine the relationship between Antarctic krill catch, sea ice concentration, and sea surface temperature (SST). Data on the Antarctic krill catch from 2003 to 2010 in CCAMLR Area 48.2 were combined with sea ice and SST data. Results showed that krill fishing in Area 48.2 took place from February to August each year but the catch was concentrated from March to July, with production during this period accounting for about 99.3% of the annual catch. Regression analysis showed that the catch per unit effort (CPUE) was clearly related to sea ice concentration and SST intervals. CPUE was negatively correlated with the area of sea ice among years (R2=0.64), and the correlation was strongest (R2=0.71) when sea ice concentration was greater than 90%. Over the months the CPUE initially increased, then decreased as the area of sea ice increased. The relationship was strongest (R2=0.88) when the concentration of sea ice was 60%—70%. There was no negative correlation among years between CPUE and the ice-free area when SST was between -2℃and 3℃ (R2=0.21), but there was a significant negative correlation when SST was between 1℃ and 2℃ (R2=0.82). Over the months, CPUE initially increased then decreased with increasing sea ice-free area, and the relationship was strongest (R2=0.94) when SST was between 0℃ and 1℃. This study shows that sea ice concentration and SST have significant effects on the abundance of krill in Area 48.2, and the findings have practical significance for the use and conservation of Antarctic krill resources
Subpixel heterogeneity of ice-wedge polygonal tundra: a multi-scale analysis of land cover and evapotranspiration in the Lena River Delta, Siberia
Get PDFIgnoring small-scale heterogeneities in Arctic land cover may bias estimates of water, heat and carbon fluxes in
large-scale climate and ecosystem models. We investigated subpixel-scale heterogeneity in CHRIS/PROBA and
Landsat-7 ETM satellite imagery over ice-wedge polygonal tundra in the Lena Delta of Siberia, and the
associated implications for evapotranspiration (ET) estimation. Field measurements were combined with aerial
and satellite data to link fine-scale (0.3m resolution) with coarse-scale (upto 30m resolution) land cover data.
A large portion of the total wet tundra (80%) and water body area (30%) appeared in the form of patches less
than 0.1 ha in size, which could not be resolved with satellite data. Wet tundra and small water bodies
represented about half of the total ET in summer. Their contribution was reduced to 20% in fall, during which ET rates from dry tundra were highest instead. Inclusion of subpixel-scale water bodies increased the total water surface area of the Lena Delta from 13% to 20%. The actual land/water proportions within each composite satellite pixel was best captured with Landsat data using a statistical downscaling approach, which is recommended for reliable large-scale modelling of water, heat and carbon exchange from permafrost landscapes
Protection of Arctic Marine Environment
No full textThe Protection of the Arctic Marine Environment Working Group(PAME) is one of six Arctic Council working groups. PAME was first established under the 1991 Arctic Environmental Protection Strategy and was continued by the 1996 Ottawa Charter that established the Arctic Council. The PAME Portal provides with a comprehensive Arctic marine shipping follow-up to the Arctic Marine Strategic Plan which was adopted by the Arctic Council Ministers at the 4th Arctic Council meeting in November 2004
University of Lapland
No full textUniversity of Lapland was founded in 1979 as the educational center for the northern Finland. The university is a member of the network University of the Arctic and acts as the international secretariat of the network
Multiple processes affecting surface seawater N2O saturation anomalies in tropical oceans and Prydz Bay, Antarctica
Get PDFWe analyzed the N2O content of surface seawater sampled from Prydz Bay, Antarctica, on a cruise track between 30°S and 30°N during the twenty-second Chinese National Antarctic Research Expedition during austral summer, 2006. The surface water showed an average pN2O value of 311.9±7.6 nL·L-1 (14.1±0.4 nmol·L-1), which was slightly undersaturated. The air-sea N2O flux in the region was -0.3±0.8 μmol·m-2·d-1; however, N2O in the surface water was oversaturated in most stations along the cruise track. Saturation anomalies were greater than 10%, with a maximum of 54.7% being observed at the Equator, followed by 31% at 10°N in the Sulu Sea. The air-sea fluxes at these locations were 12.4 and 4 μmol·m-2·d-1, respectively. Overall, the results indicated that surface water in Prydz Bay was near equilibrium with atmospheric N2O, and that ocean waters in lower latitudes acted as a N2O source. Physical processes such as stratification, ice-melt water dilution, and solar radiation dominate the factors leading to N2O saturation of surface water of Prydz Bay, while biological production and upwelling are primarily responsible for the N2O oversaturation of surface water observed in subtropical and tropical regions along the cruise track
Summertime freshwater fractions in the surface water of the western Arctic Ocean evaluated from total alkalinity
Get PDFAs a quasi-conservative tracer, measures of total alkalinity (TA) can be utilized to trace the relative fractions of freshwater and seawater. In this study, based on the TA and related data collected during the third Chinese National Arctic Research Expedition (July—September 2008, 3rd CHINARE-Arctic) and the fourth Chinese National Arctic Research Expedition (July — September 2010, 4th CHINARE-Arctic), fractions of sea-ice meltwater, river runoff, and seawater within the surface water of the western Arctic Ocean were determined using salinity and TA relationships. The largest fraction of sea-ice meltwater was found around 75°N within the Canada Basin during both surveys, which is located at the ice edge. Generally, it was found that the fraction of river runoff was less than that of sea-ice meltwater. The river runoff, composed mainly of contributions from the Yukon River carried by Bering inflow water and the Mackenzie River, was influenced by the currents, leading to two peak areas of its fraction. Our results show that the dilution effect of freshwater carried by Bering inflow water during the 3rd CHINARE-Arctic in 2008 expedition period may be stronger than that during the 4th CHINARE-Arctic in 2010 expedition period. The peak area of sea-ice meltwater fraction during the 4th CHINARE-Arctic was different from that of the 3rd CHINARE-Arctic, corresponding to their sea-ice condition
Factors influencing small-scale distribution of 10 macro-lichens in King George Island, West Antarctica
Get PDFLichens are among the main primary colonists in most terrestrial ecosystems of Antarctica, where the effects of environmental factors on spatial distribution of lichens are essential to understanding the functioning of Antarctic terrestrial ecosystems. We measured abundance of 10 frequently observed macrolichens and 15 environmental factors at a small scale (20 cm×20 cm), in the ice-free areas of Fildes Peninsula and Ardley Island, King George Island, West Antarctica, and assessed the effects of environmental factors on the local distribution of these lichens. Canonical correspondence analyses (CCA) show that 8 out of 15 environmental factors, belonging to 4 sets of variables, are important in spatial distribution of the 10 lichens. Variation partitioning analyses show that most of the variation in distribution of the 10 lichens is described by the spatial heterogeneity of substrate, bird influence and microclimate and topography, whereas human impact has no significant effects
Arctic Report Card 2012
No full textThe Arctic Report Card (www.arctic.noaa.gov/reportcard/) considers a wide range of environmental observations throughout the Arctic, and is updated annually. A major finding of the Report Card 2012 is that numerous record-setting melting events occurred, even though, with the exception of a few limited episodes, Arctic-wide it was an unremarkable year, relative to the previous decade, for a primary driver of melting - surface air temperatures. From October 2011 through August 2012, positive (warm) temperature anomalies were relatively small over
the central Arctic compared to conditions in recent years (2003-2010). Yet, in spite of these moderate conditions, new records were set for sea ice extent, terrestrial snow extent, melting at the surface of the Greenland ice sheet, and permafrost temperature