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Progress in polar upper atmospheric physics research in China
Get PDFThe Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous history of nearly 30 years of Chinese polar expeditions and major progress in polar upper atmospheric physics research. This includes the polar upper atmospheric physics conjugate observation system at Zhongshan Station in the Antarctic and Yellow River Station in the Arctic, and original research achievements in polar ionospheric fields, aurora and particle precipitation, the polar current system, polar plasma convection, geomagnetic pulsations and space plasma waves, inter-hemispheric comparisons of the space environment, space weather in polar regions, power spectrum of the incoherent scatter radar, ionospheric heating experiments and polar mesospheric summer echoes, polar ionosphere-magnetosphere numerical simulation and others. Finally, prospects for Chinese polar upper atmospheric physics research are outlined
Vertical structure of low-level atmosphere over the southeast Indian Ocean fronts
Get PDFDuring the 25th Chinese National Antarctic Research Expedition, GPS radiosondes were launched to detect the atmospheric vertical structure over the southeast Indian Ocean frontal region. Some low-level characteristics along the cruise are studied based on in-situ observation. The observations reveal that vertical distributions of the low-level wind field and air temperature field on both sides of the Subantarctic Front are very different. A stronger (weaker) vertical gradient is on the cold (warm) side, which demonstrates that the mid-latitude ocean-atmosphere interaction is active in the southeast Indian Ocean frontal region. A low-level jet is observed over the Subantarctic Front, with speed up to 14 m·s-1. For the Antarctic polar front, low-level wind speed near the sea surface is greater than that aloft, in contrast with the situation of the Subantarctic Front. Comparing satellite remote sensing data and widely-used reanalysis datasets with our in-situ observations, differences of varying magnitudes are found. Air temperature from Atmospheric Infrared Sounder (AIRS) data has a limited difference. The European Center for Medium Range Weather Forecasts Interim Re-Analysis (ERA Interim) dataset is much more consistent with the observations than the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis 1 in the southeast Indian Ocean frontal region
Validation of total ozone data between satellite and ground-based measurements at Zhongshan and Syowa stations in Antarctica
Get PDFWe present validation between total ozone from satellite and ground-based observations of the Dobson and Brewer spectrometers and ozone radiosonde at Zhongshan and Syowa Antarctic research stations, for September 2004 to March 2009. Results show that mean bias error between Zhongshan (Syowa) and Ozone Monitor Instrument Total Ozone Mapping Spectrometer (OMI-TOMS) data are −0.06%±3.32% (−0.44%±2.41%); between it and OMI Multi Axis Differential Optical Absorption Spectroscopy (OMI-DOAS) data, the error is −0.34%±4.99% (−0.22%±4.85%). Mean absolute bias error values of OMI-TOMS data are less than those of OMI-DOAS. This means that total ozone of OMI-TOMS is closer to ground-based observation than that of OMI-DOAS. Comparison between direct observational total ozone of ground-based and integrated ozone from the ozone profile measured by ozone radiosonde shows that ozone amount calculated with the Solar Backscatter Ultraviolet (SBUV) method above balloon burst height is similar to corresponding Microwave Limb Sounder (MLS) data. Therefore, MLS data can be substituted with SBUV data to estimate ozone amount above that level. Mean bias error of the MLS ozone column is 2% compared with the ozonesonde column, with standard deviation within 9.5%. Comparison of different layers from ozone profiler and MLS data indicates that at the 215 hPa layer, the MLS ozone value is high, with relative deviation more than 20%. At the 100 hPa and 68 hPa layers, the MLS ozone value is also high. This deviation is mainly in spring, during Antarctic ozone hole appearance. In this period, at the height of severe ozone loss, relative deviation of MLS ozone values is especially large
The Arctic Governance Project
No full textThe Arctic Governance Project joined preeminent researchers, indigenous leaders, and members of the policy community to frame critical questions and issues of governance in the Arctic. The Project's leadership compiled an Action Agenda and a report entitled "Arctic Governance in an Era of Transformative Change: Critical Questions, Governance Principles, Ways Forward." The recommendations contained in these documents were presented to key policymakers in the national, international and non-governmental sectors
Grove Mountains (GRV) 024237: A new ureilite from Antarctica
Get PDFUreilites share the characteristics of differentiated meteorites and of primary chondrites. GRV 024237 is a ureilite, which was found in the 19th Chinese National Antarctic Research Expedition (CHINARE), at the No. 4 moraine, Grove Mountains, Antarctica. GRV 024237 consists mainly of coarse-grained olivine (60 vol%), pigeonite (30 vol%) and opaque minerals (10 vol%). Tri-junction texture between olivine and pigeonite is common. Carbonaceous materials with minor amounts of troilite and nickel-iron metal were observed as interstitial phases. The Fa value of olivine composition varies from 6.2 to 16.8 from rim to core, but pyroxene is homogeneous in composition, with Fs 14.0 to 15.5. Both olivine and pyroxene have normal extinctions. Net-like iron or limonite veins filled in the fractures of olivine and pyroxene, and no diamond was observed. Based on petrographic and mineralogical features, GRV 024237 is a Type I and Group 2 monomict ureilite
Cognitive effects of long-term residence in the Antarctic environment
Get PDFThis study examined whether prolonged residence in the Antarctica had a significant impact on cognitive performance. Participants were members of the 24th and 25th Chinese National Antarctic Research Expeditions. Cognitive performance was measured with tests designed to evaluate short-term recognition, memory search and spatial cognition, measured four times: January, March, April, and June 2010. Age was controlled as a covariate, and data were analyzed using repeated-measures ANOVA. The results revealed that subjects’ short-term memory and recognition ability remained stable, while 82% of team members exhibited improved scores on a spatial cognitive ability test. These findings have important implications for furthering our understanding of cognitive functioning in extreme environments
Territorial nationalism and Arctic geopolitics: Iceland as an Arctic Coastal state
Get PDFThis paper explores the cultural and political significance of being acknowledged and recognized as an “Arctic coastal state”. Using Iceland as a case study, we consider how coastal state status had grown in significance as the Arctic Ocean has been re-imagined more as a polar Mediterranean and less as a frozen desert. By drawing on Michael Billig’s work on banal nationalism and popular geopolitics, the manner in which the ideas and practices associated with a “coastal state” are reproduced in elite and everyday contexts. However, we conclude by noting that thus far this appeal to Iceland as “coastal state” has gained greater traction within the Icelandic Foreign Ministry and Parliament, and it remains to be seen whether it will have a more popular resonance with Icelandic citizens. Whatever the future, it is a timely reminder that terms such as “coastal state” are caught up in national and even circumpolar identity projects
Policy Implications of Warming Permafrost
No full textThis report seeks to inform a broad audience about permafrost and communicate to decision-makers and the general public the implications of changing permafrost in a warming climate. It defines basic terminology and describes fundamental physical and biological processes that shape the permafrost landscape using the best scientific information available from published literature. The report discusses the impacts of a changing climate on ecosystems and human infrastructure in regions with significant presence of permafrost, as well as the impacts of thawing permafrost on global climate. Graphics, illustrations and photographs help explain complicated concepts and ideas in a way that is easily understood and visualized by a non-scientific audience
Progress and prospects in Chinese Antarctic surveying, mapping and remote sensing studies
Get PDFAntarctic surveying, mapping and remote sensing is one of the important aspects of the Chinese Antarctic geoscience research program that stretch back over 25 years, since the first Chinese National Antarctic Research Expedition (CHINARE) in 1984. During the 1980’s, the geodetic datum, height system and absolute gravity datum were established at the Great Wall and Zhongshan Stations. Significant contributions have been made by the construction of the Chinese Great Wall, Zhongshan and Kunlun Stations in Antarctica. Geodetic control and gravity networks were established in the King George Islands, Grove Mountains and Dome Argus. An area of more than 200 000 km2 has been mapped using satellite image data, aerial photogrammetry and in situ data. Permanent GPS stations and tide gauges have been established at both the Great Wall and Zhongshan Stations. Studies involving plate motion, precise satellite orbit determination, the gravity field, sea level change, and various GPS applications for atmospheric studies have been carried out. Based on remote sensing techniques, studies have been undertaken on ice sheet and glacier movements, the distributions of blue ice and ice crevasses, and ice mass balance. Polar digital and visual mapping techniques have been introduced, and a polar survey space database has been built. The Chinese polar scientific expedition management information system and Chinese PANDA plan display platform were developed, which provides technical support for Chinese polar management. Finally, this paper examines prospects for future Chinese Antarctic surveying, mapping and remote sensing
NUUK DECLARATION On the occasion of the 7th Ministerial Meeting of The Arctic Council, May 2011
Get PDFNUUK DECLARATION On the occasion of the Seventh Ministerial Meeting of The Arctic Council 12 May 2011, Nuuk, Greenlan