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    30 December 1963, Volume 24 Issue 4-English Previous Issue    Next Issue

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    Foreword
    Huigen Yang
    2013, 24 (4-English):  1. 
    Abstract ( 722 )   PDF (89KB) ( 721 )  
          This special issue is based on the presentations at the 13th Annual General Meeting of the Asian Forum for Polar Sciences (AFoPS-13) in New Delhi on 6-7 August 2012, chaired by Dr. Shri Rasik Ravindra, Director of National Center for Antarctic and Ocean Research of India. To strengthen both scientific and logistic collaboration among Asian countries involved in polar research is AFoPS’s main purpose. During the AFoPS-13, it was decided to publish the AFoPS proceedings annually by each member countries in turn to demonstrate progresses in Polar Science of Asian countries. On the meeting, China was given the great honor to publish the first AFoPS proceedings as a special issue of the Advances in Polar Science (APS), which is a peer-reviewed journal, published in English. APS is a comprehensive scientific journal dedicated to polar research in all scientific disciplines.     The AFoPS-13 proceedings contain 16 original scientific papers from authors of all AFoPS countries, namely: China, India, Japan, Korea and Malaysia. It covers disciplines of oceanography, atmospheric science, geology, biology and ecology. Many new findings and interesting results in these fields are presented and discussed. I would highlight some examples for your kind attention, such as: new descriptions of the Arctic marine bacterium Pseudoalteromonas sp. BSw20308, by Zeng et al. from China; the research of the phenotypic plasticity in Bacillus cereus strains by Sinha et al. from India; using of VHF meteor radar to improve the accuracy of temperature measurement near the mesopause by Kim et al. from Korea; the study of the absolute gravity in East Antarctica by Doi et al. from Japan; and the investigation of tele-connection of climate patterns in high- and low-latitudes by Mohd Nor et al. from Malaysia. I am sure that these studies will surely provide a foundation and greater space for further co-operation among AFoPS community and beyond.     I would thank all the authors and reviewers who have contributed to this special issue and acknowledge all the members of nominated editorial board for their great supports. I would also like to thank Dr. Yea-dong Kim, the director of the Korea Polar Research Institute, for his leadership to make the proceedings reality. Finally, as the guest editor in chief of this special issue, I’d particularly thanks Prof. Ruiyuan Liu, the editor in chief, and the editorial office of APS for their great efforts and cooperation to make the first proceedings a success.                                                       Guest Editor in Chief:                                                                            Huigen Yang 18 December 2013
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    Articles
    Preliminary genome analysis of psychrotolerant marine bacterium Pseudoalteromonas sp. BSw20308 reveals its potential applications
    ZENG Yinxin, YU Yong, QIAO Zongyun, LI Huirong & LUO Wei
    2013, 24 (4-English):  195-201.  DOI: 10.3724/SP.J.1085.2013.00195
    Abstract ( 1041 )   PDF (569KB) ( 1044 )  
    The genus Pseudoalteromonas is ubiquitous in the marine environment and can synthesize a wide range of extracellular compounds. Psychrotolerant Pseudoalteromonas sp. BSw20308 was isolated from the Chukchi Sea, a marginal sea of the Arctic Ocean. It produces a number of extracellular enzymes that can degrade polysaccharides and proteins. The BSw20308 genome was sequenced to 38.1-fold coverage, and the sequences were assembled into 146 contigs (≥500 bp). In total, 4 172 open reading frames (ORFs) with an average gene length of 987 bp were detected. At least 86 ORFs were predicted by sequence analysis to encode a variety of catalytic modules involved in the degradation of polysaccharides, proteins, and lipids. In addition, 36 ORFs were predicted to encode catalytic modules involved in the degradation of organic pollutants and halogenated compounds, and in the production of bioactive compounds. The draft genome sequence of BSw20308 provides new information about the ecological function and adaptation of the genus Pseudoalteromonas in Arctic marine environments, and also indicates its potential applications in the biotechnology industries (e.g., enzymology, and pollutant degradation).
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    A comparative analysis of β-mannanases of bacteria from Antarctica and Malaysia
    Clemente Michael Vui Ling Wong, Heng Keat Tam & Hui Yee Yong
    2013, 24 (4-English):  202-207.  DOI: 10.3724/SP.J.1085.2013.00202
    Abstract ( 1138 )   PDF (859KB) ( 1442 )  
    β-mannanase is an enzyme that is commonly expressed in environmental bacteria. It degrades hemicellulose found in plant material and recycles nutrients back into the environment. Because this enzyme significantly contributes to biodegradation and has recently been applied in industry, we conducted a comparative analysis of bacterial isolates found in soil samples from Schirmacher Oasis, Antarctica, and Sabah, Malaysia that were capable of degrading mannan. A total of 9 bacterial isolates from Antarctica and 30 bacterial isolates from Malaysia exhibited β-mannanase activity. These bacteria were differentiated and clustered using their random amplified polymorphic DNA (RAPD) profiles, and the β-mannanase activity of these isolates was tested at different temperatures and pH. Five out of 9 Antarctica isolates and seven out of 30 Malaysian isolates were identified based on their 16S rDNA sequences. Identified bacterial isolates from Antarctica were: MP1 (Bacillus amyloliquefaciens), MP2 (Bacillus pumilus), MP5 (Bacillus pumilus), A40 (Arthrobacter sp.), and C27 (Arthrobacter oxydans). Identified bacterial isolates from Malaysia were: Y1 (Paenibacillus sp.), Y2 (Bacillus sp.), Y16 (Paenibacillus sp.), Y18 (Paenibacillus sp.), A7 (Paenibacillus sp.), B26 (Streptomyces sp.), and D4 (Paenibacillus amylolyticus). β-mannanases produced by the Antarctica bacterial isolates MP1 (Bacillus amyloliquefaciens) and A40 (Arthrobacter sp.) were active at 5℃ and 20℃, respectively, while the β-mannanase produced by the bacterial isolate from Malaysia, A7 (Paenibacillus sp.), was active at 35℃.
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    Diversity and bioactivity of actinomycetes from Signy Island terrestrial soils, maritime Antarctic
    Shing Yi Pan, Geok Yuan Annie Tan, Peter Convey, David A. Pearce & Irene K. P. Tan
    2013, 24 (4-English):  208-212.  DOI: 10.3724/SP.J.1085.2013.00208
    Abstract ( 1316 )   PDF (508KB) ( 1283 )  
      The Antarctic represents a largely untapped source for isolation of new microorganisms with potential to produce bioactive natural products. Actinomycetes are of special interest among such microorganisms as they are known to produce a large number of natural products, many of which have clinical, pharmaceutical or agricultural applications. We isolated, characterized and classified actinomycetes from soil samples collected from different locations on Signy Island, South Orkney Islands, in the maritime Antarctic. A total of 95 putative actinomycete strains were isolated from eight soil samples using eight types of selective isolation media. The strains were dereplicated into 16 groups based on morphology and Amplified Ribosomal DNA Restriction Analysis (ARDRA) patterns. Analysis of 16S rRNA gene sequences of representatives from each group showed that streptomycetes were the dominant actinomycetes isolated from these soils; however, there were also several strains belonging to diverse and rare genera in the class Actinobacteria, including Demetria, Glaciibacter, Kocuria, Marmoricola, Nakamurella and Tsukamurella. In addition, screening for antibacterial activity and non-ribosomal peptide synthetase genes showed that many of the actinomycete strains have the potential to produce antibacterial compounds.
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    Phenotypic plasticity in Bacillus cereus strains isolated from various Antarctic habitats
    Rupesh Kumar Sinha & Kottekkatu Padinchati Krishnan
    2013, 24 (4-English):  213-222.  DOI: 10.3724/SP.J.1085.2013.00213
    Abstract ( 1130 )   PDF (1170KB) ( 1112 )  
    We studied five strains of psychrotolerant Bacillus cereus (B. cereus) isolated from Antarctic snow (BCsn), ice (BCic), lake water (BCwr), sediment (BCsd), and soil (BCsl) samples in terms of their growth, biochemical properties, and heat shock responses. Analyses of growth kinetics at 4℃ showed that BCsn had the fastest generation time (16.1 h), whereas BCwr had the slowest (30.8 h). Strain BCsd formed the largest zone of lipid hydrolysis (18 mm) whereas BCsn formed the smallest zone        (3 mm).Only BCsd produced gelatinase. These physiological differences illustrate adaptations of B. cereus isolates to different niches. Strains BCsl and BCwr were resistant to all 12 of the antibiotics tested. Strains BCsn, BCic, and BCsd were resistant to cell wall synthesis inhibitors (penicillin and ampicillin) and susceptible to protein synthesis inhibitors (tetracycline and streptomycin). A carbon-substrate utilization assay revealed that BCsn, BCic, and BCwr could specifically utilize D-glucose-6-phosphate, salicin, and 2’-deoxyadenosine, respectively, indicating a degree of metabolic diversity among these Antarctic B. cereus strains. An analysis of heat shock proteins (HSPs) produced in response to a 60℃ heat treatment revealed significant variations in the amounts of HSP33 (p = 0.01, df = 4), HSP44 (p = 0.003, df = 4), and HSP60 (p = 0.04, df = 4) among the strains. This emphasizes the importance of HSPs in bacterial taxonomy. These results show that there are considerable adaptive variations among B. cereus strains from extremophilic environments. This could be significant in evaluating the taxonomy and evolution of this species.
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    Transposon mutagenesis of Psychrobacter cryohalolentis PAMC 21807 by tri-parental conjugation
    Hyun-Jeong Jeong, Hyoungseok Lee, Soon Gyu Hong, Jang-Cheon Cho, Hong Kum Lee & Yoo Kyung Lee
    2013, 24 (4-English):  223-230.  DOI: 10.3724/SP.J.1085.2013.00223
    Abstract ( 1070 )   PDF (1477KB) ( 1588 )  
    Random mutagenesis is commonly used to study gene function. The screening of mutants exhibiting specific phenotypes assists in the identification of phenotype-related genes. In the current study, we isolated Antarctic bacteria, and developed a transposon Tn5 mutagenesis system. A total of 26 strains were isolated from seawater and freshwater near Antarctic King Sejong Research Station, King George Island. Six Psychrobacter strains were identified as psychrophilic, with optimal growth temperatures of 10℃ or 15℃ Psychrobacter cryohalolentis PAMC 21807 with a high growth rate at 4℃ was selected for transposon mutagenesis. Tri-parental conjugation with a plasmid containing Tn5 produced 13 putative recombinants containing the selectable marker. Genomic Southern hybridization confirmed Tn5 existed as episomes for seven recombinants, and for a single recombinant, Tn5 was integrated into the genome of Psychrobacter cryohalolentis PAMC 21807. The result indicates that the mutagenesis method, although successful, has a relatively low rate. The psychrophilic bacteria isolated in this study may be a useful resource for studying cold adaptation mechanisms, and the mutagenesis method can be applied to genetic analysis.
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    Analysis software for upper atmospheric data developed by the IUGONET project and its application to polar science
    Yoshimasa Tanaka, Atsuki Shinbori, Tomoaki Hori, Yukinobu Koyama, Shuji Abe, Norio Umemura, Yuka Sato, Manabu Yagi, Satoru UeNo, Akiyo Yatagai, Yasunobu Ogawa & Yoshizumi Miyoshi
    2013, 24 (4-English):  231-240.  DOI: 10.3724/SP.J.1085.2013.00231
    Abstract ( 1370 )   PDF (4943KB) ( 1937 )  
      To comprehensively understand the Arctic and Antarctic upper atmosphere, it is often crucial to analyze various data that are obtained from many regions. Infrastructure that promotes such interdisciplinary studies on the upper atmosphere has been developed by a Japanese inter-university project called the Inter-university Upper atmosphere Global Observation Network (IUGONET). The objective of this paper is to describe the infrastructure and tools developed by IUGONET. We focus on the data analysis software. It is written in Interactive Data Language (IDL) and is a plug-in for the THEMIS Data Analysis Software suite (TDAS), which is a set of IDL libraries used to visualize and analyze satellite- and ground-based data. We present plots of upper atmospheric data provided by IUGONET as examples of applications, and verify the usefulness of the software in the study of polar science. We discuss IUGONET’s new and unique developments, i.e., an executable file of TDAS that can run on the IDL Virtual Machine, IDL routines to retrieve metadata from the IUGONET database, and an archive of 3-D simulation data that uses the Common Data Format so that it can easily be used with TDAS.
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    VHF meteor radar at King Sejong Station, Antarctica
    Jeong-Han Kim, Geonhwa Jee, Changsup Lee & Yong-Ha Kim
    2013, 24 (4-English):  241-247.  DOI: 10.3724/SP.J.1085.2013.00241
    Abstract ( 1134 )   PDF (2029KB) ( 1355 )  
    Since 2002, we have been observing the mesosphere and lower thermosphere (MLT) region over King Sejong Station (KSS; 62.22°S, 58.78°W), Antarctica, using various instruments such as the Spectral Airglow Temperature Imager (SATI), All Sky Camera (ASC) and VHF meteor radar. The meteor radar, installed in March 2007, continuously measures neutral winds in the altitude region 70–110 km and neutral temperature near the mesopause 24 h?d-1, regardless of weather conditions. In this study, we present results of an analysis of the neutral wind data for gravity wave activity over the tip of the Antarctic Peninsula, where such activity is known to be very high. Also presented is temperature estimation from measurement of the decay times of meteor trails, which is compared with other temperature measurements from SATI and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the Thermosphere Ionosphere Mesosphere Energy and Dynamics (TIMED) satellite.
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    Remote sensing backscattering model for sea ice: Theoretical modelling and analysis
    Syabeela Syahali & Hong Tat Ewe
    2013, 24 (4-English):  248-257.  DOI: 10.3724/SP.J.1085.2013.00248
    Abstract ( 966 )   PDF (2788KB) ( 1248 )  
    Remote sensing has been used in Antarctic studies as an earth observation technique to study the polar region. A remote sensing forward model is an important tool in polar research to study and understand scattering mechanisms and sensitivity of physical parameters of snow and sea ice. In this paper, a reliable theoretical model to study sea ice is developed. The theoretical model in a prior work was improved by including multiple-surface scattering, based on an existing integral equation model and additional second-order surface-volume scattering. This model is applied to a desalinated ice layer above thick saline ice and analyzed using different frequencies, bottom surface roughness and sea-ice layer thickness. Improvement in calculation of the backscattering coefficient of the sea-ice layer is investigated for both co-polarized and cross-polarized returns. The effect on each scattering mechanism is also investigated, to understand in more detail the effect of surface multiple scattering and second-order surface-volume scattering. Comparisons are also made with field measurement results, to validate the theoretical model. Results show improvement in the total backscattering coefficient for cross-polarized return in the studied range, suggesting that multiple-surface scattering and surface-volume scattering up to second order are important scattering mechanisms in the sea-ice layer and should not be ignored in polar research.
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    Ice concentration assimilation in a regional ice-ocean coupled model and its application in sea ice forecasting
    LI Qun, ZHANG Zhanhai, SUN Li & WU Huiding
    2013, 24 (4-English):  258-264.  DOI: 10.3724/SP.J.1085.2013.00258
    Abstract ( 1107 )   PDF (3673KB) ( 985 )  
      A reasonable initial state of ice concentration is essential for accurate short-term forecasts of sea ice using ice-ocean coupled models. In this study, sea ice concentration data are assimilated into an operational ice forecast system based on a combined optimal interpolation and nudging scheme. The scheme produces a modeled sea ice concentration at every time step, based on the difference between observational and forecast data and on the ratio of observational error to modeled error. The impact and the effectiveness of data assimilation are investigated. Significant improvements to predictions of sea ice extent were obtained through the assimilation of ice concentration, and minor improvements through the adjustment of the upper ocean properties. The assimilation of ice thickness data did not significantly improve predictions. Forecast experiments show that the forecast accuracy is higher in summer, and that the errors on five-day forecasts occur mainly around the marginal ice zone.
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    Near-surface structure and energy characteristics of the Antarctic Circumpolar Current
    GAO Libao, YU Weidong, WANG Haiyuan & LIU Yanliang
    2013, 24 (4-English):  265-272.  DOI: 10.3724/SP.J.1085.2013.00265
    Abstract ( 912 )   PDF (7000KB) ( 765 )  
    Historical surface drifter observations collected from the Southern Ocean are used to study the near-surface structure, variability, and energy characteristics of the Antarctic Circumpolar Current (ACC). A strong, nearly zonal ACC combined with complex fronts dominates the circulation system in the Southern Ocean. Standard variance ellipses indicate that both the Agulhas Return Current and the East Australian Warm Current are stable supplements of the near-surface ACC, and that the anticyclonic gyre formed by the Brazil warm current and the Malvinas cold current is stable throughout the year. During austral winter, the current velocity increases because of the enhanced westerly wind. Aroused by the meridional motion of the ACC, the meridional velocity shows greater instability characteristics than the zonal velocity does over the core current. Additionally, the ACC exhibits an eastward declining trend in the core current velocity from southern Africa. The characteristics of the ACC are also argued from the perspective of energy. The energy distribution suggests that the mean kinetic energy (MKE), eddy kinetic energy (EKE), and  are strong over the core currents of the ACC. However, in contrast, EKE/MKE suggests there is much less (more) eddy dissipation in regions with strong (weak) energy distribution. Both meridional and zonal energy variations are studied to illustrate additional details of the ACC energy characteristics. Generally, all the energy forms except EKE/MKE present west-east reducing trends, which coincide with the velocity statistics. Eddy dissipation has a much greater effect on MKE in the northern part of the Southern Ocean.
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    Spatial variability of soil nutrients in Punta Fort William, Greenwich Island, maritime Antarctic
    Yii Siang Hii, Siti Aisyah Alias, Monica Riofrío, Nadia Ordó?ez & Hernán Moreano
    2013, 24 (4-English):  273-280.  DOI: 10.3724/SP.J.1085.2013.00273
    Abstract ( 1082 )   PDF (516KB) ( 1080 )  
    This study aims to report baseline soil nutrients, specifically the organic carbon, nitrogen and phosphorus profile, in soil samples collected from Punta Fort William on Greenwich Island in maritime Antarctic. Samples were collected along two transect lines during the early summer of 2008. Ward’s method of hierarchical agglomerative clustering was employed to group the sampling points based on their physico-chemical properties. In this context, the soil samples can be grouped into three major clusters: (1) Samples with intensive biological activities, (2) samples from the area recently exposed by glacial retreat and (3) samples from barren and dried areas. Nutrient contents in Punta Fort William are driven by the intensity of biological activities as well as melt water from the Quito glacier.
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    Hydrochemistry and sediment characteristics of polar periglacial lacustrine environments on Fisher Island and Broknes Peninsula, East Antarctica
    Rajesh Asthana, Prakash Kumar Shrivastava, Hari Bahadur Srivastava, Mirza Javed Beg & Pradeep Kumar
    2013, 24 (4-English):  281-295.  DOI: 10.3724/SP.J.1085.2013.00281
    Abstract ( 1166 )   PDF (4074KB) ( 1134 )  
    Fisher Island and Broknes Peninsula in the Larsemann Hills constitute part of a polar lowland periglacial environment between marine and glacial ecosystems. The landscape is characterized by gently rolling hills and broad valleys interspersed with lakes formed in glacially scoured basins. We analyzed the physicochemical parameters and the ionic constituents of water samples from 10 lakes in each of these two locations. Our results showed considerable differences between the two regions and demonstrated the influence of lithology and processes including weathering, evaporation, and atmospheric precipitation. All major cations and anions in the lake waters showed positive correlations indicating balanced ionic concentrations. Unconsolidated sediments were sparsely distributed and scattered over glacial deposits, valley fills, and occasional moraine ridges. The type and rate of sedimentation was mainly controlled by surface run-off and aeolian influx. The sediment samples from lake beds and the catchment area on Fisher Island were immature and poorly to very poorly sorted, consisting of gravelly sand with negligible silt and finer fractions. Sediments had a polymodal grain size distribution with the two major populations lying between −2 and −1 phi and between 0 and 1.5 phi. The sediments were lithic arenite to arkosic in composition and the microtextures imprinted over quartz grains were dominated by mechanical textures resulting from several stages of glacial crushing and grinding. The presence of deep dissolution cavities, cryptocrystalline precipitation, and euhedral crystal growth signified the effect of chemical activity after the deposition of grains in the lacustrine environment.
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    Global distributions of storm-time ionospheric currents as seen in geomagnetic field variations
    Atsuki Shinbori, Tomoaki Hori, Yoshimasa Tanaka, Yukinobu Koyama, Takashi Kikuchi & Tsutomu Nagatsuma
    2013, 24 (4-English):  296-314.  DOI: 10.3724/SP.J.1085.2013.00296
    Abstract ( 1123 )   PDF (10435KB) ( 768 )  
    To investigate temporal and spatial evolution of global geomagnetic field variations from high-latitude to the equator during geomagnetic storms, we analyzed ground geomagnetic field disturbances from high latitudes to the magnetic equator. The daytime ionospheric equivalent current during the storm main phase showed that twin-vortex ionospheric currents driven by the Region 1 field-aligned currents (R1 FACs) are intensified significantly and expand to the low-latitude region of ~30° magnetic latitude. Centers of the currents were located around 70° and 65° in the morning and afternoon, respectively. Corresponding to intensification of the R1 FACs, an enhancement of the eastward/westward equatorial electrojet occurred at the daytime/nighttime dip equator. This signature suggests that the enhanced convection electric field penetrates to both the daytime and nighttime equator. During the recovery phase, the daytime equivalent current showed that two new pairs of twin vortices, which are different from two-cell ionospheric currents driven by the R1 FACs, appear in the polar cap and mid latitude. The former led to enhanced northward Bz (NBZ) FACs driven by lobe reconnection tailward of the cusps, owing to the northward interplanetary magnetic field (IMF). The latter was generated by enhanced Region 2 field-aligned currents (R2 FACs). Associated with these magnetic field variations in the mid-latitudes and polar cap, the equatorial magnetic field variation showed a strongly negative signature, produced by the westward equatorial electrojet current caused by the dusk-to-dawn electric field.
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    Study of the climatic teleconnection between the Siberian high and maritime continent warm pool
    Mohd Fadzil Firdzaus Bin Mohd Nor & Azizan Bin Abu Samah
    2013, 24 (4-English):  315-325.  DOI: 10.3724/SP.J.1085.2013.00315
    Abstract ( 1177 )   PDF (11781KB) ( 889 )  
    This paper attempts to establish a method for analysing the relationship between the polar and equatorial climate of the Northern Hemisphere. The Arctic Oscillation (AO) is known to have no direct relationship with the monsoon over the Maritime Continent (MC). Thus, an index called the Siberian High(SH)–Maritime Continent(MC) Index (SHMCI) is developed to represent the mean sea level pressure difference between the SH and the warm pool over the MC. This index indicates a strong link with the monsoon circulation. A positive (strong) value of the SHMCI is associated with strong meridional winds and intense and frequent cold surge events over the South China Sea. The correlation between the AO index and the SHMCI is -0.39, which is medium but statistically significant; however, it is not sufficiently conclusive to infer direct correlation. Nevertheless, the SHMCI can be used as a tool to relate the AO with the monsoon over the MC because of the influence demonstrated by the AO towards the SH. Further analysis on the convergence and divergence anomalies over the MC reveals an impact discernible only from the SHMCI. This implies that the SHMCI manifests clearly the relationship between the Arctic and equatorial climate.
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    Analysis of recent climate change over the Arctic using ERA-Interim reanalysis data
    Seong-Joong Kim, Hye-Sun Choi, Baek-Min Kim, Sang-Jong Park, Taehyoun Shim & Joo-Hong Kim
    2013, 24 (4-English):  326-338.  DOI: 10.3724/SP.J.1085.2013.00326
    Abstract ( 1334 )   PDF (9262KB) ( 911 )  
    This study investigates recent climate change over the Arctic and its link to the mid-latitudes using the ERA-Interim global atmospheric reanalysis data from the European Center for Medium-Range Weather Forecast (ECMWF). Since 1979, substantial surface warming, associated with the increase in anthropogenic greenhouse gases, has occurred over the Arctic. The greatest warming in winter has taken place offshore in the Kara-Barents Sea, and is associated with the increase in turbulent heat fluxes from the marginal ice zone. In contrast to the marked warming over the Arctic Ocean in winter, substantial cooling appears over Siberia and eastern Asia, linked to the reduction of Arctic sea ice during the freezing season (September–March). However, in summer, very little change is observed in surface air temperature over the Arctic because increased radiative heat melts the sea ice and the amount of turbulent heat gain from the ocean is relatively small. The heat stored in the upper ocean mixed layer in summer with the opening of the Arctic Ocean is released back to the atmosphere as turbulent heat fluxes during the autumn and through to the following spring. This warming of the Arctic and the reduced sea ice amplifies surface cooling over Siberia and eastern Asia in winter.
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    Letters
    Field measurements of absolute gravity in East Antarctica
    Koichiro Doi, Hideaki Hayakawa, Takahito Kazama, Toshihiro Higashi, Shingo Osono, Yoichi Fukuda, Jun Nishijima, Yuichi Aoyama & Junichi Ueda
    2013, 24 (4-English):  339-343.  DOI: 10.3724/SP.J.1085.2013.00339
    Abstract ( 1243 )   PDF (1502KB) ( 1216 )  
    This paper reports the results of field-based absolute gravity measurements aimed at detecting gravity change and crustal displacement caused by glacial isostatic adjustment. The project was initiated within the framework of the 53rd Japanese Antarctic Research Expedition (JARE53). Absolute gravity measurements, together with GPS measurements, were planned at several outcrops along the Prince Olav Coast and Sôya Coast of East Antarctica, including at Syowa Station. Since the icebreaker Shirase (AGB 5003) was unable to moor alongside Syowa Station, operations were somewhat restricted during JARE53. However, despite this setback, we were able to complete measurements at two sites: Syowa Station and Langhovde. The absolute gravity value at the Syowa Station IAGBN (A) site, observed using an FG-5 absolute gravimeter (serial number 210; FG-5 #210), was  982 524 322.7±0.1 µGal, and the gravity change rate at the beginning of 2012 was –0.26 µGal?a-1. An absolute gravity value of 982 535 584.2±0.7 µGal was obtained using a portable A-10 absolute gravimeter (serial number 017; A-10 #017) at the newly located site AGS01 in Langhovde.
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    Call for Papers for Two Special Issues of Advances in Polar Science
    2013, 24 (4-English):  344-345. 
    Abstract ( 787 )   PDF (125KB) ( 661 )  
      Dear Colleagues, We invite you to submit a article, a review, a letter, or a trend to a special issue on“The rapid change of Arctic sea ice and its possible effects on high- and mid-latitude weather and climate”, or another special issue on “The current status on the ecosystem of Antarctic Peninsula” of the Journal Advances in Polar Science (APS). APS is an international, peer-reviewed journal jointly sponsored by the Polar Research Institute of China (PRIC) and the Chinese Arctic and Antarctic Administration. It is a quarterly journal published in March, June, September and December by Science Press of China and circulated internationally. Article publishing in APS is free of charge thanks to generous funding from PRIC. For more details, please visit the websites http://mc03.manuscriptcentral.com/apsci or http://journal. polar.gov.cn/CN/volumn/current.shtml. Please respond to indicate whether or not you will accept this invitation to offer a paper. We kindly request that you confirm your commitment ASAP and please provide a preliminary title and a brief description of the proposed paper. Thank you in advance for your consideration to submit an article to one of the two special issues, and we encourage you to share this announcement broadly with interested colleagues. Any queries should be addressed to journal@pric.gov.cn I  Special Issue on “The Rapid Change of Arctic Sea Ice and itsPossible Effects on High- and Mid-Latitude Weather and Climate” Rapid changes of Arctic sea ice cover have been in the focus of the international research community in recent years. Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean. Up to now, China has performed five research cruises to the Arctic Ocean resulting with a significant number of research output, and China is now to implement the 6th cruise to the Arctic Ocean in the summer of 2014. APS is preparing to publish the special issue at the end of 2014, providing an international forum to summarize the recent advances on this important topic. Scientific articles on the following research themes fit well within the scope of this special issue: (1) Future trends of Arctic rapidly changing sea ice – will there possibly be no sea ice in summer later in the 21st century; (2) Key factors controlling the rapid changes in the Arctic sea ice; (3) Differences of Arctic and Antarctic sea ice changes and their causes; (4) Why do the numerical simulation results deviate significantly from in-situ analyses; (5) Rapid change of Arctic sea ice and its linkages on climate in the high latitudes of the Northern Hemisphere; (6) The impact of Arctic sea ice changes on the weather and climate in China; (7) Forcing and response mechanisms of the Arctic tropospheric and stratospheric atmospheric circulation and ocean circulation on the changes in the Arctic sea ice; (8) Linkage of Arctic atmospheric circulation and westerly circulation changes; (9) Economic and social assessment of Arctic sea ice rapid decline. The agenda of this issue is the following: •Paper submission deadline: 31 May 2014 •Final acceptance deadline: 15 October 2014 •Publication: December 2014 Guest Editors Prof. Matti Leppäranta, Department of Physics, University of Helsinki, Finland Prof. Timo Vihma, Finnish Meteorological Institute, Finland Prof. Huiding Wu, National Marine Environmental Forecasting Center, China II  Special Issue on “The Current Status on the Ecosystem of Antarctic Peninsula” It is obvious that the weather in the Antarctic Peninsula is becoming warmer in recent decades. It will influence the ecosystem in and around Antarctic Peninsula, and also provide a more suitable surviving “environment” for alien species. Increased knowledge of the status on the Antarctic Peninsula ecosystem can be used for the conservation and management of its ecosystem and for developing scenarios of its future state. APS is preparing to publish a special issue entitled “The current status on the ecosystem of Antarctic Peninsula”. This issue will provide a forum summarizing the recent advances on expeditions and research based or focused on the ecosystems of Antarctic Peninsula. The scientific articles stressing the following research themes may fit well within the scope of this special issue: (1) Past and present biodiversity across terrestrial, limnological, glacial and marine environments (2) Past and present environments (3) Interactions between organisms and environments (4) Interactions between organisms and organisms (5) Alien species (6) Global change and human activities on ecosystem effects This special issue is scheduled to publish in March of 2015, which was in memory of the 30th anniversary of foundation of Chinese Great Wall Station. The agenda of this issue is the following: •Paper submission deadline: 31 June, 2014 •Final acceptance deadline: 30 November, 2014 •Publication: March of 2015 Guest editors Prof. José Retamales, Chilean Antarctic Institute Prof. Liguang Sun, University of Science and Technology of China Associate Prof. Yong Yu, Leader of Chinese Great Wall Station, 29th CHINARE, Polar Research Institute of China
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