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Hotspots of seabirds and marine mammals between New Zealand and the Ross Gyre: importance of hydrographic features
Get PDFThis article is part of our long-term study on the quantitative at-sea distribution of the marine “upper trophic levels”—seabirds and marine mammals—in polar ecosystems, aiming at quantifying the factors influencing their distribution as well as detecting possible spatial and temporal changes, with special attention to hydrography and to global climate changes. During an expedition of icebreaking RV Polarstern in February 2010, along the North–South transect between New Zealand and the Ross Gyre, off the Ross Sea, 3200 seabirds belonging to 22 identified pelagic species were recorded during 338 half-hour transect counts. Four major hotspots were identified. These were in Sub-tropical Water off New Zealand (up to 300 birds per count), and at the main Southern Ocean fronts: the Sub-Antarctic Front (up to 240 per count), the Antarctic Front (up to 150 per count) and the Polar Front (up to 200 per count), representing the vast majority of recorded seabirds. The most numerous species in the three frontal zones were: prions—mainly slender-billed Pachyptila belcheri—and Salvin’s albatross Thalassarche [cauta] salvini. The eight more abundant species represented 2650 birds, i.e. more than 80% of the total. A random forest clustering method identified four groups of seabird species occupying similar oceanographic niches
An Arctic Indigenous Knowledge System of Landscape, Climate, and Human Interactions. Evenki Reindeer Herders and Hunters
Get PDFSnow, Water, Ice and Permafrost in the Arctic (SWIPA) 2017
Get PDFThe Snow, Water, Ice and Permafrost in the Arctic (SWIPA) assessment is a periodic update to the Arctic Climate Impact Assessment, published in 2005 by AMAP, CAFF, and the International Arctic Science Committee (IASC)
Chinese radioglaciological studies on the Antarctic ice sheet: progress and prospects
Get PDFChinese radioglaciological studies on the Antarctic ice sheet (AIS) began in 2004/05 when the 21st Chinese National Antarctic Research Expedition (CHINARE 21) team arrived at Dome A for the first time and radio echo sounding (RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32 (2015/16) and CHINARE 33 (2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work
Telecommunications Infrastructure in the Arctic; A Circumpolar Assessment
Get PDFThis report presents the Task Forces investigation and analysis into the technologies presently available to users, and identifies gaps in the infrastructure. The report also provides an overview of each State's telecommunications priorities.
Changes occur rapidly in the telecommunications industry, and it is inevitable that some of the information or details contained in this report will quickly become outdated. Readers should view this report as a "snapshot" of the state of telecommunications infrastructure in the Arctic, and should certainly be attentive to ongoing developments
Response of polar regions to emerging organic pollutant organophosphorus esters (OPEs), a review
Get PDFPolar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current research on organophosphorus esters (OPEs) in polar regions by reviewing the literature on distribution, source and transport of OPEs. Current research on OPEs reveals significant anthropogenic influences in both polar regions. As well as the expected occurrence in the Arctic, OPEs were found on the Antarctic Ice Sheet up to 650 km from the coast, and the OPE concentrations were higher at high elevation due to cold climate retention. The immediate source of OPEs for inland Antarctica might be the Southern Ocean surrounding the continent, where OPEs in aerosols and seawater showed comparable concentrations to remote areas in the European Arctic. A positive correlation between aerosol OPEs in the open water and the surface vortex of ocean currents indicates that these compounds may be transported and accumulated in the ocean currents. The Antarctica Circumpolar Current accumulates them in the marginal seas of Antarctica
Holocene climate change and anthropogenic activity records in Svalbard: a unique perspective based on Chinese research from Ny-Ålesund
Get PDFClimate change in the Arctic region is more rapid than that in other areas owing to Arctic amplification. To better understand climate change and the driving mechanisms, long-term historical reconstructions throughout the Holocene and high-resolution records of the past few hundred years are required. Intense anthropogenic activities in the Arctic have had a great impact on the local environment. Here, we review the Holocene climate change record, responses of the ecosystems to climate change, and the anthropogenic impacts on the environment based mainly on Chinese research from Ny-Ålesund. Climate reconstruction studies from Svalbard have revealed several cold episodes during the Holocene, which are consistent with ice rafting events in the North Atlantic region and glacier activity from Greenland, Iceland, and Svalbard. The ecosystem also showed corresponding responses to climate change, especially during the late Holocene. Over recent decades, anthropogenic activities have caused serious pollution and deterioration to the local environment in Svalbard in areas frequented by people. Greater environmental protection is therefore needed to reduce the anthropogenic impacts on the local environment
Progress in Chinese research on water masses and circulation in the Arctic and subarctic ocean
Get PDFThe Arctic Ocean and Arctic sea ice have undergone a series of rapid changes. Oceanographic surveying has become one of the key missions of the Chinese National Arctic Research Expeditions since 1999. Using the data obtained in these surveys and from other sources, Chinese researchers have carried out a series of studies in the field of Arctic physical oceanography. The Near Sea-surface Temperature Maximum, freshwater content and heat flux in different regions of the Arctic have drawn wide attention from Chinese researchers. Arctic circulation is changing with the decline of sea ice, which is also influencing the structure and distribution of water masses. Studies have also focused on these issues. In this paper, the main results of research on water masses, currents, the structure of the upper ocean and other major hydrological phenomena over the past two decades are summarized
Glaciological observations at Dome Argus, East Antarctica
Get PDFDome Argus (Dome A) in East Antarctica is a potentially likely site to meet one of the major objectives of the International Partnerships in Ice Core Sciences (IPICS) on the oldest ice core, and thus has aroused wide public and scientific interest. Since 2004/2005, many glaciological investigations have been conducted in this region. These have included GPS and ground-penetrating radar surveys, snow pit and ice core drilling, stake network measurements, and meteorological observations. In this article, the main results of these glaciological investigations in the Dome A region are summarized. We present details of the surface mass balance on different timescales and its spatial variability, geochemical characteristics of the surface snow, and paleo-environment reconstruction of ice cores. Finally, perspectives on the prospects for future studies are suggested
Cryogenic Displacement and Accumulation of Biogenic Methane in Frozen Soils
Get PDFEvidences of highly localized methane fluxes are reported from the Arctic shelf, hot spots of methane emissions in thermokarst lakes, and are believed to evolve to features like Yamal crater on land. The origin of large methane outbursts is problematic. Here we show, that the biogenic methane (δ13C ≤ −71‰) which formed before and during soil freezing is presently held in the permafrost. Field and experimental observations show that methane tends to accumulate at the permafrost table or in the coarse-grained lithological pockets surrounded by the sediments less-permeable for gas. Our field observations, radiocarbon dating, laboratory tests and theory all suggest that depending on the soil structure and freezing dynamics, this methane may have been displaced downwards tens of meters during freezing and has accumulated in the lithological pockets. The initial flux of methane from the one pocket disclosed by drilling was at a rate of more than 2.5 kg C(CH4) m−2 h−1. The age of the methane was 8–18 thousand years younger than the age of the sediments, suggesting that it was displaced tens of meters during freezing. The theoretical background provided the insight on the cryogenic displacement of methane in support of the field and experimental data. Upon freezing of sediments, methane follows water migration and either dissipates in the freezing soils or concentrates at certain places controlled by the freezing rate, initial methane distribution and soil structure