检索结果-南通市图书馆

Retrieval of snow depth on antarctic sea ice from the FY-3D MWRI data

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2023年第12期42卷 105-117页

作者： Zhongnan Yan Xiaoping Pang Qing Ji Yizhuo Chen Chongxin Luo Pei Fan Zeyu Liang Chinese antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China

The snow depth on sea ice is an extremely critical part of the *** and understanding changes of snow depth on antarctic sea ice is beneficial for research on sea ice and global climate *** Microwave Radiation Imager(MWRI)sensor aboard the Chinese FengYun-3D(FY-3D)satellite has great potential for obtaining information of the spatial and temporal distribution of snow depth on the sea *** comparing in-situ snow depth measurements during the 35th Chinese antarctic Research Expedition(CHINARE-35),we took advantage of the combination of multiple gradient ratio(GR(36V,10V)and GR(36V,18V))derived from the measured brightness temperature of FY-3D MWRI to estimate the snow *** method could simultaneously introduce the advantages of high and low GR in the snow depth retrieval model and perform well in both deep and shallow snow *** on this,we constructed a novel model to retrieve the FY-3D MWRI snow depth on antarctic sea *** new model validated by the ship-based observational snow depth data from CHINARE-35 and the snow depth measured by snow buoys from the Alfred Wegener Institute(AWI)suggest that the model proposed in this study performs better than traditional models,with root mean square deviations(RMSDs)of 8.59 cm and 7.71 cm,respectively.A comparison with the snow depth measured from Operation iceBridge(OIB)project indicates that FY-3D MWRI snow depth was more accurate than the released snow depth product from the *** Snow and ice Data Center(NSIDC)and the National Tibetan Plateau Data Center(NTPDC).The spatial distribution of the snow depth from FY-3D MWRI agrees basically with that from iceSat-2;this demonstrates its reliability for estimating antarctic snow depth,and thus has great potential for understanding snow depth variations on antarctic sea ice in the context of global climate change.

关键词： snow depth antarctic sea ice passive microwave FY-3D

Anomalous change of the antarctic sea ice and global sea level change

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 1996年第2期15卷 193-208页

作者： Xie Simei Zou Bing Wang Yi and Bao Chenglan (National Marine Environment Forecasting Center, State oceanic Administration, Beijing 100081, China) National Marine Environment Forecasting Center State Oceanic Administration Beijing 100081 China

In this paper, the long-term variation trend of the antarctic sea ice in 1973～1994 and the inter-decade variation rule of the global sea level are analyzed. It is found that the sea ice area in the antarctic in the 1980s was significantly less than in the 1970s and the average global sea level height value in the 1980s was also significantly higher than in the 1970s. Connecting variation of both and analyzing their physical mechanism, it indicates that the accumulated sea ice anomaly value in the 1980s less than in the 1970s means a global climate warming, the sea water temperature and air temperature were obviously higher in the 1980s it introduced the long-term accumulated sea ice decreased greatly; a higher sea water temperature introduced sea water volume expanding, and more icebergs transporting from the ice cover in the antarctic continent to ocean in the warmer year. As a result induced by these multi-causes, the global sea level raised significantly in the 1980s. The global average sea level value in the 1980s, was 22 mm higher than in the 1970s. The sea level raising(SLR) was distributed unevenly. It is especially true in the Pacific Ocean with two expensive we level raising regions in the Northeast Pacific and Southeast Pacific as well as a raising region near the Bering sea; and with two descent regions in the Northwest and Southwest Pacific. It is considered that this kind of uneven SLR distribution closely relates to the sustained decreasing of the antarctic sea ice. The higher sea water tem This study was supported both by the National Natural Science Foundation of China under contrast Nod 49376252 and by the National '85' Plan 'Key Project 903': 7th *** in the south ocean introduces a rather warmer water temperature of the Peru Cold Current which is a northward branch of the South Oceanic Current along the South American continent, then it is easier to the occurrence of El Nino event. When El Nino event occurs, the prevailed tropical easte

关键词： antarctic sea ice global sea level long-term variation El Nino event oceanic circulation

Temporal and spatial variation characteristics of antarctic sea ice and the causes of its record decline during 2015–2016: a review

在线全文

学校读者我要写书评

暂无评论

Advances in Polar Science 2023年第1期34卷 5-16页

作者： YANG Yingyue LIU Hailong WANG Xidong School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Polar Research Institute of China Shanghai 200136China Key Laboratory for Polar Science MNRPolar Research Institute of ChinaShanghai 200136China Key Laboratory of Marine Hazards Forecasting MNRHohai UniversityNanjing 210024China College of Ocean Hohai UniversityNanjing 210098China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

Satellite observations over the past four decades have shown that the long-term trend of antarctic sea ice extent(SIE)is opposite to the trend of sea ice extent in the *** sea ice extent continues to decline while antarctic SIE is generally on the rise except for a dramatic decline in 2015–*** on the 40-year climatology from 1981 to 2020,antarctic SIE anomaly in December 2016 is–2.1×10^(6) km^(2),reaching the minimum since *** are many studies on the cause of this record *** present review summarizes the spatial and temporal characters of antarctic sea ice and recaps major findings on the causes of record decline in 2015–2016 from the perspective of direct thermodynamic and dynamic process of atmosphere and ocean as well as the modulation of climate ***,the challenges and key scientific problems to be solved in the future of antarctic sea ice research are presented.

关键词： antarctic sea ice sea ice extent sea ice concentration climate variability

Definition of Arctic and antarctic sea ice Variation Index

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polar Science 2004年第2期15卷 137-142页

作者：陈红霞刘娜潘增弟张庆华 Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the Chinese Academy of Sciences Beijing China Key Lab of Marine Science and Numerical Modeling First Institute of Oceanography SOA Qingdao 266061 China Key Lab of Marine Science and Numerical Modeling First Institute of Oceanography SOA Qingdao 266061 ChinaCollege of Physical and Environmental Oceanography Chinese Ocean University Qingdao 266003 China Polar Research Institute of China Shanghai 200136 China

It is well known that varying of the sea ice not only in the antarctic but also in the Arctic has an active influence on the globe atmosphere and ocean. In order to understand the sea ice variation in detail, for the first time, an objective index of the Arctic and antarctic sea ice variation is defined by projecting the monthly sea ice concentration anomalies poleward of 20°N or 20°S onto the EOF (empirical orthogonal function)-1 spatial pattern. Comparing with some work in former studies of polar sea ice, the index has the potential for clarifying the variability of sea ice in northern and southern high latitudes.

关键词： Arctic sea ice antarctic sea ice variation index.

Spatial-temporal characters of antarctic sea ice variation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polar Science 2004年第2期15卷 75-84页

作者：马丽娟陆龙骅卞林根 Chinese Academy of Meteorological Sciences Beijing 100081 China

Using sea ice concentration dataset covering the period of 1968-2002 obtained from the Hadley Center of UK, this paper investigates characters of antarctic sea ice variations .The finding demonstrates that the change of mean sea-ice extent is almost consistent with that of sea-ice area, so sea-ice extent can be chosen to go on this research. The maximum and the minimum of antarctic sea ice appear in September and February respectively. The maximum and the maximal variation of sea ice appear in Weddell sea and Ross sea, while the minimum and the minimal variation of sea-ice appear in antarctic Peninsula. In recent 35 years, as a whole, antarctic sea ice decreased distinctly. Moreover, there are 5 subdivision characteristic regions considering their different variations. Hereinto, the sea-ice extent of Weddell sea and Ross sea regions extends and area increases, while the sea-ice extent of the other three regions contracts and area decreases. They are all of obvious 2-4 years and 5-7 years significant oscillation periods. It is of significance for further understanding the sea-ice-air interaction in antarctica region and discussing the relationship between sea-ice variation and atmospheric circulation.

关键词： antarctic sea ice mathematical diagnostic spatial-temporal variation global change.

Synoptic mode of antarctic summer sea ice superimposed on interannual and decadal variability

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2021年第2期12卷 147-161页

作者： YU Le-Jiang ZHONG Shi-Yuan SUI Cui-Juan ZHANG Zhao-Ru SUN Bo MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai200136China Department of Geography Environment and Spatial SciencesMichigan State UniversityEast Lansing48824USA National Marine Environmental Forecasting Center Beijing10008JChina School of Oceanography Shanghai Jiao Tong UniversityShanghai200240China

In contrast to decreased Arctic sea ice extent,antarctic sea ice extent shows a somewhat increased *** is a large interannual variability of antarctic sea ice,especially in the Pacific sector of the Southern *** change and variability of antarctic sea ice in synoptic timescales in the recent decades remain *** identify synoptic modes of variability of antarctic summer sea ice by applying the Self Organizing Map(SOM)technique to daily sea ice concentration data for the period 1979–*** 40%of the variability is characterized by opposite changes between sea ice cover in the Bellingshausen,Amundsen and western Ross seas and in the rest of the antarctic seas,and another 30%by meridional asymmetry in the Weddell,Amundsen,and Ross *** of these spatial patterns may be explained by the dynamics and thermodynamic processes associated with anomalous atmospheric circulations related to the Southern Annular Mode(SAM)with a structure of strong zonal *** interannual variability of the sea ice modes appears to have little connection to SAM,and only a weak relation to *** annual frequencies of SOM node occurrences also show a great decadal *** 9 appears mainly prior to 1990;while node 1 occurs mainly after *** decadal variability of nodes 1 and 9 is associated with the asymmetrical SAM,which results from two wavetrains excited over northern Australia and the southeastern Indian *** results further highlight the importance of understanding the role of southern mid-to-high latitude atmospheric intrinsic variability in predicting antarctic summer sea ice variations from synoptic to decadal timescales.

关键词： antarctic sea ice sea ice variability Southern annular mode Amundsen sea low Self organizing map

The signature analysis of summer antarctic sea-ice distribution by ship-based sea-ice observation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Cold and Arid Regions 2009年第4期1卷 300-306页

作者： ShuLin Tang 1,Ning Li 1,AnNan Jiang 2,XingRu Zhou 1 1.China Railway 21st Bureau Group CO.,LTD,Lanzhou 730000,China.2.Institute of Highway and Bridge,Dalian Maritime University,Dalian 116026,China. China Railway 21st Bureau Group CO. LTD Institute of Highway and Bridge Dalian Maritime University Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Based on the Chinese 19th National antarctic Research Expedition,we carried out ship-based antarctic sea-ice observa-tion on icebreaker Xue Long using antarctic sea-ice process and climate (ASPeCt) criteria during austral ***-ice distribution data were obtained along nearly 6,500 km of the ship’s *** measurement parameters included sea-ice thickness,sea-ice concentration,snow thickness,and floe *** showed the presence of the large spatial varia-tions of the observed sea-ice ***-ice concentration varied between 0 and 80 percent and reached its peak value in Weddell sea because of the specific dynamical process affecting in summer sea-ice *** are large areas of open water along the study *** ice and the upper snow thickness of the section varied between 10 cm and 210 cm and 2 cm and 80 cm,respectively,and each reaches its peak values near Amery ice *** floe size varied from less than 10 cm and the maximum of more than 2,000 km along the section.

关键词： antarctic sea ice ship-based observation

Microseism Variations in Response to antarctic seasonal Changes in sea ice Extent

在线全文

学校读者我要写书评

暂无评论

Earthquake Research in China 2020年第2期34卷 264-284页

作者： XU Xiaoqing LIN Jianmin FANG Sunke Marine Acoustics and Remote Sensing Laboratory Zhejiang Ocean UniversityZhoushan 316021China Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province Ocean CollegeZhejiang UniversityZhoushan 316021China State Key Laboratory of Marine Geology School of Ocean and Earth ScienceTongji UniversityShanghai 200092China

The temporal and spatial distributions of antarctic sea ice play important roles in both the generation mechanisms and the signal characteristics of microseisms. This link paves the way for seismological investigations of antarctic sea ice. Here we present an overview of the current state of seismological research about microseisms on antarctic sea ice. We first briefly review satellite remote-sensing observations of antarctic sea ice over the past 50 years. We then systematically expound upon the generation mechanisms and source distribution of microseisms in relation to seismic noise investigations of sea ice, and the characteristics of antarctic microseisms and relationship with sea ice variations are further analyzed. We also analyze the continuous data recorded at seismic station BEAR in West antarctica from 2011 to 2018 and compare the microseism observations with the corresponding satellite remotesensing observations of antarctic sea ice. Our results show that:(1) the microseisms from the coastal regions of West antarctica exhibit clear seasonal variations,SFM with maximum intensities every April-May and minimum intensities around every October-November;while DFM intensities peak every February-March,and reach the minimum around every October. Comparatively,the strong seasonal periodicity of antarctic sea ice in better agreement with the observed DFM;and(2) microseism decay is not synchronous with sea ice expansion since the microseism intensity is also linked to the source location,source intensity(e. g.,ocean storms,ocean wave field),and other factors. Finally, we discuss the effect of Southern Annular Mode on antarctic sea ice and microseisms,as well as the current limitations and potential of employing seismological investigations to elucidate antarctic sea ice variations and climate change.

关键词： antarctic sea ice Microseism Climate change Southern annular Mode

Purification and characterization of cold-active endo-1,4-β-glucanase produced by Pseudoalteromonas sp. AN545 from antarctica

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Oceanology and Limnology 2011年第5期29卷 1086-1092页

作者：沈继红阚光锋史翠娟雷振环解秋菊钱文佳 Key Laboratory of Marine Bio-active Substances State Oceanic Administration School of the Ocean Harbin Institute of Technology at Weihai

A bacterium hydrolyzing carboxymethylcellulose, isolated from antarctic sea ice, was identified as Pseudoalteromonas sp. based on 16S rDNA gene sequences and named as Pseudoalteromonas sp. AN545. The extracellular endo-1,4-β-glucanase AN-1 was purified successively by ammonium sulfate precipitation, DEAE-Sepharose ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The molecular mass of AN-1 was estimated to be 47.5 kDa utilizing SDS-PAGE and gel chromatography analysis. AN-1 could hydrolyze caboxymethylcellulose, avicel and β-glucan, but not cellobiose, xylan and p-Nitrophenyl-β-D-glucopyranoside. The optimal temperature and pH for the β-glucanase activity of AN-1 were determined to be at 30℃ and pH 6.0, respectively. AN-1 was stable at acidic solutions of pH 5.0-6.5 and temperatures below 30℃ for 1 h. Moreover, the specific activity was enhanced by Ca2＋ and Mg2., and inhibited by Cu2＋. The kinetic parameters Michaelis constant （Km） and maximum velocity （Vmax） of AN-1 were 3.96 mg/mL and 6.06×10-2 mg/（***）, respectively.

关键词： Pseudoalteromonas endo-l,4-β-glucanase cold-active enzyme antarctic sea ice stability