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Spratlies Archipelago as the Australasian Tektite Impact Crater, Details of Formation &Richard Muller’s Dust Cloud Explanation for the Mid-Pleistocene Ice Age Cycle Transition 被引量:2
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作者 Hermann G. W. Burchard 《Open Journal of Geology》 2018年第1期1-8,共8页
Several significant events of a geological nature occurred approximately 800 ka before the present: (1) Australasian tektite fall (AA), (2) Brunhes-Matuyama geomagnetic reversal (BMR), (3) mid-Pleistocene changes in i... Several significant events of a geological nature occurred approximately 800 ka before the present: (1) Australasian tektite fall (AA), (2) Brunhes-Matuyama geomagnetic reversal (BMR), (3) mid-Pleistocene changes in ice age cycles. Add to these the undated fault system (4) in the South-West (SW) of the South China Sea (SCS). Here we offer a unified cause for all four of these in (5), an impact in the SCS of a large, massive cosmic object, likely a comet, obliquely coming from the SW at an extremely shallow angle, striking the Sunda shelf yet unexploded with the shock of its compressed air bow wave, and causing the continual shelf and slope to collapse, resulting in the fault system (4), then traveling almost tangentially to the surface, exploding at impact with the sea surface, ejecting the tektites (1), creating the formation underlying the later atolls of Spratlies Archipelago (6), Nansha Islands in Chinese, & causing the BMR (2). An explanation of event (3) was Richard Muller’s hypothesis of planet Earth passing through an interplanetary dust cloud periodically due to ecliptic precession. Here we hypothesize this cloud actually is a belt of Australasian tektites ejected into space at super-orbital velocities that Earth encounters about every 100 ka. 展开更多
关键词 Spratlies ARCHIPELAGO Cosmic Object Impact Crater Australasian TEKTITES Brunhes-Matuyama Geomagnetic Reversal RICHARD Muller Dust Cloud Hypothesis Mid-Pleistocene ice Age CYCLE TRANSITION Google Earth High Resolution Update
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Insufficiency of Cellular Energy (ICE) May Precede Neurodegeneration in Alzheimer’s Disease and Be Treatable via the Alternative Cellular Energy (ACE) Pathway 被引量:2
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作者 W. John Martin 《Advances in Alzheimer's Disease》 2017年第1期1-12,共12页
The term neurodegeneration emphasizes the destruction of neuronal cells as the primary explanation of many major neurological illnesses, including Alzheimer’s disease. Specialized functioning of cells requires more c... The term neurodegeneration emphasizes the destruction of neuronal cells as the primary explanation of many major neurological illnesses, including Alzheimer’s disease. Specialized functioning of cells requires more cellular energy than is needed for basic cell survival. Cells can acquire energy both from the metabolism of food and from the alternative cellular energy (ACE) pathway. The ACE pathway is an added dynamic (kinetic) quality of the body’s fluids occurring from the absorption of an external force termed KELEA (Kinetic Energy Limiting Electrostatic Attraction). KELEA is attracted to separated electrical charges and is seemingly partially released as the charges become more closely linked. As suggested elsewhere, the fluctuating electrical activity in the brain may attract KELEA from the environment and, thereby, contribute to the body’s ACE pathway. Certain illnesses affecting the brain may impede this proposed antenna function of the brain, leading to a systemic insufficiency of cellular energy (ICE). Furthermore, individual neurons may derive some of the energy for their own activities from the repetitive depolarization of the cell. This may explain why hyper-excitability of neurons can occur in response to cell damage. This adaptive mechanism is unlikely to be sustainable, however, especially if there is a continuing need to synthesize neurotransmitters and membrane ion channels. The energy deficient neurons would then become quiescent and, although remaining viable, would not perform their intended specialized functions. Actual cell death would not necessarily occur till much later in the disease process. The distinction between quiescent and degenerated cells is important since the ACE pathway can be enhanced by several means, including the regular consumption of KELEA activated water. This, in turn, may improve the proposed antenna function of individual neurons, leading to a sustained restoration of specialized function via the ACE pathway. This paper explores this novel concept and provides a rationale for clinical testing of KELEA activated water in patients with neurological and psychiatric illnesses, including Alzheimer’s disease. 展开更多
关键词 Alzheimers Disease Alternative CELLULAR ENERGY ACE INSUFFICIENCY of CELLULAR ENERGY ice Kinetic ENERGY Limiting Electrostatic Attraction KELEA Homeopathy Enercel Enerceutical Calorie Metabolism Electrical Charge Membrane Potential NEURODEGENERATION Psychiatry
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基于WEB Service技术的可视化质量体系远程审核系统的研究与开发 被引量:1
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作者 任显林 张根保 +1 位作者 梁淑明 周丽 《制造技术与机床》 CSCD 北大核心 2005年第7期91-94,共4页
首次提出并阐述了质量体系远程审核的概念,分析了实现质量体系远程审核的设计思想,给出了远程审核的网络总体结构,综合运用WEBService技术、组件技术、音视频网络通讯技术开发了可视化质量体系远程审核系统,解决了通过Internet跨地域、... 首次提出并阐述了质量体系远程审核的概念,分析了实现质量体系远程审核的设计思想,给出了远程审核的网络总体结构,综合运用WEBService技术、组件技术、音视频网络通讯技术开发了可视化质量体系远程审核系统,解决了通过Internet跨地域、跨行业的质量体系认证审核与监督审核全过程,保障了质量体系有效运行与持续改进。 展开更多
关键词 ice技术 WEB Internet
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Hyper-Excitability Followed by Functional Quiescence in Neuronal Cells Caused by Insufficient Cellular Energy (ICE): Treatable by Enhancing the Alternative Cellular Energy (ACE) Pathway 被引量:1
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作者 W. John Martin 《World Journal of Neuroscience》 2017年第3期257-266,共10页
Living organisms derive energy for cellular activities through three primary mechanisms. The first is photosynthesis, which is restricted to plants and certain bacteria. It uses energy in sunlight to combine carbon di... Living organisms derive energy for cellular activities through three primary mechanisms. The first is photosynthesis, which is restricted to plants and certain bacteria. It uses energy in sunlight to combine carbon dioxide with water to form carbohydrates plus oxygen. The second is chemical energy, which is ob-tainable by all organisms from the cellular metabolism of carbohydrates and other organic molecules. The third mechanism of obtaining cellular energy is the alternative cellular energy (ACE) pathway. The ACE pathway is expressed as an added dynamic (kinetic) quality of the body’s fluids. It results from the absorption of an environmental force termed KELEA (kinetic energy limiting electrostatic attraction). The fundamental role of KELEA is presumably to pre-vent the fusion and annihilation of electrostatically attracted opposing electrical charges. KELEA can loosen the hydrogen bonding between fluid molecules. KELEA benefits living organisms in part by enabling more efficient biochemical reactions. Cells require a minimal amount of energy to remain viable. Additional energy is required to undertake specialized cellular functions. Illnesses result if cells have insufficient cellular energy (ICE) for their specialized functions. Since KELEA is attracted to separated electrical charges, it is presumably attracted to the electrical charges comprising the membrane potential of cells. It is proposed that the depolarization of neuronal cells leads to the partial release of KELEA for use by the depolarized cell and as a contribution to the overall activation of the body’s fluids. Many brain illnesses currently attributed to cellular neurodegeneration are explainable as neuronal cells’ adaptations to ICE. The adaptations likely comprise initial hyper-excitability to obtain additional KELEA, followed by functional quiescence prior to actual neuronal cell death. Clinical recovery during both the hyper-excitable and hypoactive phases is potentially achievable by enhancing the ACE pathway. Furthermore, among the restored specialized functions of quiescent neuronal cells may be the capacity to again attract KELEA, leading to sustainable recovery. The opportunity exists for extended clinical trials involving the ACE pathway in neurological and psychiatric illnesses. 展开更多
关键词 ALTERNATIVE CELLULAR ENERGY (ACE) PATHWAY Insufficiency of CELLULAR ENERGY ice KELEA Kinetic ENERGY Limiting Electrostatic Attraction Neurodegeneration Membrane Potential Chemical Reactions Neurology Psychiatry
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Some recent advances in remote sensing-based monitoring of changes in the Greenland Ice Sheet
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作者 FENG Tiantian JIA Jinyu +5 位作者 WANG Wei YU Zeran LIU Xingchen LI Guojun GU Yuanyuan LI Rongxing 《Advances in Polar Science》 CSCD 2024年第2期275-280,共6页
The mass balance of the Greenland Ice Sheet(GrIS)plays a crucial role in global sea level change.Since the 1960s,remote sensing missions have been providing extensive and continuous observation data for change monitor... The mass balance of the Greenland Ice Sheet(GrIS)plays a crucial role in global sea level change.Since the 1960s,remote sensing missions have been providing extensive and continuous observation data for change monitoring of the GrIS.In this paper,we present our recent research results from remote sensing-based GrIS change monitoring.First,historical satellite data are processed and used to fill data gaps and are combined with existing partial maps,completing an ice velocity map of the GrIS from the 1960s to 1980s.This map provides valuable data for estimating the historical mass balance of Greenland.Second,the monthly gravimetry-based mass balance of the GrIS from 2002 to 2020 is estimated by combining Gravity Recovery and Climate Experiment(GRACE)and GRACE Follow On(GRACE-FO)data.It is found that the GrIS has lost a total mass of approximately 4443±75 Gt during this period.Third,based on Global Land Ice Measurements from Space(GLIMS),an updated Greenland glacier inventory is achieved utilizing data collected between 2006 and 2020.This inventory provides more detailed and up-to-data glacier boundaries of Greenland.Overall,these advances provide essential data support for estimating the mass balance of the GrIS,contributing to the advancement of research on global sea level change. 展开更多
关键词 Greenland ice Sheet remote sensing change monitoring ice velocity satellite gravimetry glacier inventory
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Impacts of Ice-Ocean Stress on the Subpolar Southern Ocean:Role of the Ocean Surface Current
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作者 Yang WU Zhaomin WANG +1 位作者 Chengyan LIU Liangjun YAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期293-309,共17页
The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting t... The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting two simulations that include and exclude the OSC in the calculation of the ice-ocean stress(IOS), using an eddy-permitting coupled ocean-sea ice global model. By comparing the results of these two experiments, significant increases of 5%, 27%, and 24%, were found in the subpolar Southern Ocean when excluding the OSC in the IOS calculation for the ocean surface stress,upwelling, and downwelling, respectively. Excluding the OSC in the IOS calculation also visibly strengthens the total mechanical energy input to the OSC by about 16%, and increases the eddy kinetic energy and mean kinetic energy by about38% and 12%, respectively. Moreover, the response of the meridional overturning circulation in the Southern Ocean yields respective increases of about 16% and 15% for the upper and lower branches;and the subpolar gyres are also found to considerably intensify, by about 12%, 11%, and 11% in the Weddell Gyre, the Ross Gyre, and the Australian-Antarctic Gyre, respectively. The strengthened ocean circulations and Ekman pumping result in a warmer sea surface temperature(SST), and hence an incremental surface heat loss. The increased sea ice drift and warm SST lead to an expansion of the sea ice area and a reduction of sea ice volume. These results emphasize the importance of OSCs in the air-sea-ice interactions on the global ocean circulations and the mass balance of Antarctic ice shelves, and this component may become more significant as the rapid change of Antarctic sea ice. 展开更多
关键词 subpolar Southern Ocean Antarctic sea ice ice-ocean stress air-sea-ice-ocean interaction ocean surface current MITgcm-ECCO2
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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression 被引量:1
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作者 DONG Wen-bo ZHOU Li +2 位作者 DING Shi-feng WANG Ai-ming CAI Jin-yan 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期313-325,共13页
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ... Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second. 展开更多
关键词 ice channel ship navigation IDENTIFICATION image segmentation corner point regression
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毛竹ICE基因家族的全基因组鉴定及低温胁迫下的表达模式分析
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作者 王书伟 周明兵 《浙江农林大学学报》 CAS CSCD 北大核心 2024年第3期568-576,共9页
【目的】对毛竹Phyllostachys edulis ICE基因家族进行鉴定及分析,找出响应毛竹抗寒关键家族成员,研究毛竹ICE基因的生物学功能、响应低温胁迫的分子机制及遗传转化,为提高毛竹抗寒性奠定理论基础。【方法】利用生物信息学方法分析毛竹... 【目的】对毛竹Phyllostachys edulis ICE基因家族进行鉴定及分析,找出响应毛竹抗寒关键家族成员,研究毛竹ICE基因的生物学功能、响应低温胁迫的分子机制及遗传转化,为提高毛竹抗寒性奠定理论基础。【方法】利用生物信息学方法分析毛竹ICE基因家族成员,并对4、0、−2℃低温处理0(对照)、0.5、1.0、24.0、48.0 h的毛竹生理指标和ICE基因的表达模式进行分析。【结果】共鉴定了4个毛竹ICE基因。保守结构域和多重序列比对分析表明:PeICE基因结构高度相似。系统发育关系及启动子顺式作用元件分析显示:PeICE基因与水稻Oryza sativa亲缘关系更近,同时存在大量与非生物胁迫相关的顺式作用元件。活性氧自由基(ROS)染色发现随着处理时间增长,ROS染色逐渐加深,但是其0℃处理24.0 h、−2℃处理1.0 h后染色逐渐减弱。脯氨酸(Pro)质量摩尔浓度、超氧化物歧化酶(SOD)活性显示:4和0℃条件下,Pro质量摩尔浓度和SOD活性整体增加,但−2℃时低于对照。过氧化物酶(POD)活性显示:在3个低温处理下均增加。ICE基因表达模式分析发现:4、0℃处理时PeICE表达量整体增加,且都以PeICE3增量最明显;而−2℃处理下PeICE整体表达量水平低于对照。【结论】随着温度降低和处理时间增强,毛竹受到的损伤不断增强,其内酶活系统以及ICE基因积极响应低温胁迫,其中,PeICE3对低温胁迫最为敏感,但在−2℃时,ICE基因表达量并未增加,推测该基因家族响应了寒冷胁迫而非冷冻胁迫。 展开更多
关键词 ice基因家族
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Joint Probability Analysis and Prediction of Sea Ice Conditions in Liaodong Bay
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作者 LIAO Zhenkun DONG Sheng +2 位作者 TAO Shanshan HUA Yunfei JIA Ning 《Journal of Ocean University of China》 CAS CSCD 2024年第1期57-68,共12页
Sea ice conditions in Liaodong Bay of China are often described by sea ice grades,which classify annual sea ice conditions based on the annual maximum sea ice thickness(AM-SIT)and annual maximum floating ice extent(AM... Sea ice conditions in Liaodong Bay of China are often described by sea ice grades,which classify annual sea ice conditions based on the annual maximum sea ice thickness(AM-SIT)and annual maximum floating ice extent(AM-FIE).The joint probability distribution of AM-SIT and AM-FIE was established on the basis of their data pairs from 1949/1950 to 2019/2020 in Liaodong Bay.The joint intensity index of the sea ice condition in the current year is calculated,and the joint classification criteria of the sea ice grades in past years are established on the basis of the joint intensity index series.A comparison of the joint criteria with the 1973 and 2022 criteria revealed that the joint criteria of the sea ice grade match well,and the joint intensity index can be used to quantify the sea ice condition over the years.A time series analysis of the sea ice grades and the joint intensity index sequences based on the joint criteria are then performed.Results show a decreasing trend of the sea ice condition from 1949/1950 to 2019/2020,a mutation in 1990/1991,and a period of approximately 91 years of the sea ice condition.In addition,the Gray-Markov model(GMM)is applied to predict the joint sea ice grade and the joint intensity index of the sea ice condition series in future years,and the error between the results and the actual sea ice condition in 2020/2021 is small. 展开更多
关键词 sea ice grade ice thickness floating ice extent Liaodong Bay COPULA
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Spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice in multiple dimensions during 1979 to 2020
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作者 Yu Guo Xiaoli Wang +1 位作者 He Xu Xiyong Hou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期102-114,共13页
Arctic sea ice is broadly regarded as an indicator and amplifier of global climate change.The rapid changes in Arctic sea ice have been widely concerned.However,the spatiotemporal changes in the horizontal and vertica... Arctic sea ice is broadly regarded as an indicator and amplifier of global climate change.The rapid changes in Arctic sea ice have been widely concerned.However,the spatiotemporal changes in the horizontal and vertical dimensions of Arctic sea ice and its asymmetry during the melt and freeze seasons are rarely quantified simultaneously based on multiple sources of the same long time series.In this study,the spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice were investigated from both the horizontal and vertical dimensions during 1979–2020 based on remote sensing and assimilation data.The results indicated that Arctic sea ice was declining at a remarkably high rate of–5.4×10^(4) km^(2)/a in sea ice area(SIA)and–2.2 cm/a in sea ice thickness(SIT)during 1979 to 2020,and the reduction of SIA and SIT was the largest in summer and the smallest in winter.Spatially,compared with other sub-regions,SIA showed a sharper declining trend in the Barents Sea,Kara Sea,and East Siberian Sea,while SIT presented a larger downward trend in the northern Canadian Archipelago,northern Greenland,and the East Siberian Sea.Regarding to the seasonal trend of sea ice on sub-region scale,the reduction rate of SIA exhibited an apparent spatial heterogeneity among seasons,especially in summer and winter,i.e.,the sub-regions linked to the open ocean exhibited a higher decline rate in winter;however,the other sub-regions blocked by the coastlines presented a greater decline rate in summer.For SIT,the sub-regions such as the Beaufort Sea,East Siberian Sea,Chukchi Sea,Central Arctic,and Canadian Archipelago always showed a higher downward rate in all seasons.Furthermore,a striking freeze-thaw asymmetry of Arctic sea ice was also detected.Comparing sea ice changes in different dimensions,sea ice over most regions in the Arctic showed an early retreat and rapid advance in the horizontal dimension but late melting and gradual freezing in the vertical dimension.The amount of sea ice melting and freezing was disequilibrium in the Arctic during the considered period,and the rate of sea ice melting was 0.3×10^(4) km^(2)/a and 0.01 cm/a higher than that of freezing in the horizontal and vertical dimensions,respectively.Moreover,there were notable shifts in the melting and freezing of Arctic sea ice in 1997/2003 and 2000/2004,respectively,in the horizontal/vertical dimension. 展开更多
关键词 Arctic sea ice sea ice area sea ice thickness spatiotemporal variation freeze-thaw asymmetry
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An improved algorithm for retrieving thin sea ice thickness in the Arctic Ocean from SMOS and SMAP L-band radiometer data
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作者 Lian He Senwen Huang +1 位作者 Fengming Hui Xiao Cheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期127-138,共12页
The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer data.This SI... The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer data.This SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice temperature.The relationship between the SIT and PR was found to be almost stable across the five selected regions.The SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction sensors.The results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT data.The proposed algorithm can be used for thin sea ice thickness(<1.0 m)estimation in the Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical. 展开更多
关键词 Arctic sea ice sea ice thickness remote sensing Soil Moisture Active Passive(SMAP) Soil Moisture Ocean Salinity and Soil(SMOS)
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Advances in ice avalanches on the Tibetan Plateau
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作者 TANG Minggao LI Guang +4 位作者 ZHAO Huanle XU Qiang WU Guangjian YANG Wei GUO Daojing 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1814-1829,共16页
As some of the greatest natural disasters in the cryosphere,ice avalanches(IAs)seriously threaten lives and cause catastrophic damage to the resource environment,but a comprehensive overview of the state of knowledge ... As some of the greatest natural disasters in the cryosphere,ice avalanches(IAs)seriously threaten lives and cause catastrophic damage to the resource environment,but a comprehensive overview of the state of knowledge on IAs remains lacking.We summarized 63 IAs on the Tibetan Plateau(TP)since the 20th century,of which,over 20 IAs occurred after the 21st century.The distributions of IAs are mainly concentrated in the southeastern and northwestern TP,and the occurrence time of IAs is mostly concentrated from July to September.We highlight recent advances in mechanical properties and genetic mechanisms of IAs and emphasize that temperature,rainfall,and seismicity are the inducing factors.The failure modes of IAs are summarized into 6 categories by examples:slip pulling type,slip toppling type,slip breaking type,water level collapse type,cave roof collapse type,and wedge failure type.Finally,we deliver recommendations concerning the risk assessment and prediction of IAs.The results provide important scientific value for addressing climate change and resisting glacier-related hazards. 展开更多
关键词 ice avalanche Global warming Genetic mechanism Risk assessment Tibetan Plateau
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The sudden ocean warming and its potential influences on earlyfrozen landfast ice in the Prydz Bay, East Antarctica
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作者 Haihan Hu Jiechen Zhao +4 位作者 Jingkai Ma Igor Bashmachnikov Natalia Gnatiuk Bo Xu Fengming Hui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期65-77,共13页
The ocean conditions beneath the ice cover play a key role in understanding the sea ice mass balance in the polar regions.An integrated high-frequency ice-ocean observation system,including Acoustic Doppler Velocimete... The ocean conditions beneath the ice cover play a key role in understanding the sea ice mass balance in the polar regions.An integrated high-frequency ice-ocean observation system,including Acoustic Doppler Velocimeter,Conductivity-Temperature-Depth Sensor,and Sea Ice Mass Balance Array(SIMBA),was deployed in the landfast ice region close to the Chinese Zhongshan Station in Antarctica.A sudden ocean warming of 0.14℃(p<0.01)was observed beneath early-frozen landfast ice,from(−1.60±0.03)℃during April 16-19 to(−1.46±0.07)℃during April 20-23,2021,which is the only significant warming event in the nearly 8-month records.The sudden ocean warming brought a double rise in oceanic heat flux,from(21.7±11.1)W/m^(2) during April 16-19 to(44.8±21.3)W/m^(2) during April 20-23,2021,which shifted the original growth phase at the ice bottom,leading to a 2 cm melting,as shown from SIMBA and borehole observations.Simultaneously,the slowdown of ice bottom freezing decreased salt rejection,and the daily trend of observed ocean salinity changed from+0.02 d^(-1) during April 16-19,2021 to+0.003 d^(-1) during April 20-23,2021.The potential reasons are increased air temperature due to the transit cyclones and the weakened vertical ocean mixing due to the tide phase transformation from semi-diurnal to diurnal.The high-frequency observations within the ice-ocean boundary layer enhance the comprehensive investigation of the ocean’s influence on ice evolution at a daily scale. 展开更多
关键词 sudden ocean warming oceanic heat flux landfast ice Zhongshan Station in-situ observation
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The variation in basal channels and basal melt rates of Pine Island Ice Shelf
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作者 Mingliang Liu Zemin Wang +2 位作者 Baojun Zhang Xiangyu Song Jiachun An 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期22-34,共13页
In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly... In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly impact the stability of the PIIS.In this study,we used a variety of remote sensing data,including Landsat,REMA DEM,ICESat-1 and ICESat-2 satellite altimetry observations,and Ice Bridge airborne measurements,to study the spatiotemporal changes in the basal channels from 2003 to 2020 and basal melt rate from 2010 to 2017 of the PIIS under the Eulerian framework.We found that the basal channels are highly developed in the PIIS,with a total length exceeding 450 km.Most of the basal channels are ocean-sourced or groundingline-sourced basal channels,caused by the rapid melting under the ice shelf or near the groundingline.A raised seabed prevented warm water intrusion into the eastern branch of the PIIS,resulting in a lower basal melt rate in that area.In contrast,a deepsea trough facilitates warm seawater into the mainstream and the western branch of the PIIS,resulting in a higher basal melt rate in the main-stream,and the surface elevation changes above the basal channels of the mainstream and western branch are more significant.The El Ni?o event in 2015–2016 possibly slowed down the basal melting of the PIIS by modulating wind field,surface sea temperature and depth seawater temperature.Ocean and atmospheric changes were driven by El Ni?o,which can further explain and confirm the changes in the basal melting of the PIIS. 展开更多
关键词 Pine Island ice Shelf basal channel basal melt rate digital elevation models(DEMs) satellite altimetry
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Study on Image Recognition Algorithm for Residual Snow and Ice on Photovoltaic Modules
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作者 Yongcan Zhu JiawenWang +3 位作者 Ye Zhang Long Zhao Botao Jiang Xinbo Huang 《Energy Engineering》 EI 2024年第4期895-911,共17页
The accumulation of snow and ice on PV modules can have a detrimental impact on power generation,leading to reduced efficiency for prolonged periods.Thus,it becomes imperative to develop an intelligent system capable ... The accumulation of snow and ice on PV modules can have a detrimental impact on power generation,leading to reduced efficiency for prolonged periods.Thus,it becomes imperative to develop an intelligent system capable of accurately assessing the extent of snow and ice coverage on PV modules.To address this issue,the article proposes an innovative ice and snow recognition algorithm that effectively segments the ice and snow areas within the collected images.Furthermore,the algorithm incorporates an analysis of the morphological characteristics of ice and snow coverage on PV modules,allowing for the establishment of a residual ice and snow recognition process.This process utilizes both the external ellipse method and the pixel statistical method to refine the identification process.The effectiveness of the proposed algorithm is validated through extensive testing with isolated and continuous snow area pictures.The results demonstrate the algorithm’s accuracy and reliability in identifying and quantifying residual snow and ice on PV modules.In conclusion,this research presents a valuable method for accurately detecting and quantifying snow and ice coverage on PV modules.This breakthrough is of utmost significance for PV power plants,as it enables predictions of power generation efficiency and facilitates efficient PV maintenance during the challenging winter conditions characterized by snow and ice.By proactively managing snow and ice coverage,PV power plants can optimize energy production and minimize downtime,ensuring a sustainable and reliable renewable energy supply. 展开更多
关键词 Photovoltaic(PV)module residual snow and ice snow detection feature extraction image processing
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Impacts of High-Frequency Atmospheric Forcing on Southern OceanCirculation and Antarctic Sea Ice 被引量:4
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作者 Yang WU Zhaomin WANG +1 位作者 Chengyan LIU and Xia LIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第5期515-531,共17页
The relative contributions of atmospheric fluctuations on 6 h?2 d,2?8 d,and 8 d?1 month time scales to the changes in the air?sea fluxes,the SO circulation,and Antarctic sea ice are investigated.It was found that the ... The relative contributions of atmospheric fluctuations on 6 h?2 d,2?8 d,and 8 d?1 month time scales to the changes in the air?sea fluxes,the SO circulation,and Antarctic sea ice are investigated.It was found that the imposed forcing variability on the three time scales creates a significant increase in wind power input,and hence an increase of about 50%,97%,and 5%of eddy kinetic energy relative to the simulation driven by monthly forcing,respectively.Also,SO circulation and the strength of the upper cell of meridional overturning circulation become strengthened.These results indicate more dominant effects of atmospheric variability on the 2?8 d time scale on the SO circulation.Meanwhile,the 6 h?2 d(2?8 d)atmospheric variability causes an increase in the total sea-ice extent,area,and volume,by about 33%,30%,and 19%(17%,20%,and 25%),respectively,relative to those in the experiment forced by monthly atmospheric variables.Such significant sea-ice increases are caused by a cooler ocean surface and stronger sea-ice transports owing to the enhanced heat losses and air-ice stresses induced by the atmospheric variability at 6 h?2 d and 2?8 d,while the effects of the variability at 8 d?1 month are rather weak.The influences of atmospheric variability found here mainly result from wind fluctuations.Our findings in this study indicate the importance of properly resolving high-frequency atmospheric variability in modeling studies. 展开更多
关键词 HIGH-FREQUENCY atmospheric variability MOMENTUM FLUXES BUOYANCY FLUXES Southern Ocean circula tion ANTARCTIC sea ice MITgcm-ECCO2
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Satellite-observed trends in the Arctic sea ice concentration for the period 1979–2016 被引量:11
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作者 WANG Yunhe BI Haibo +5 位作者 HUANG Haijun LIU Yanxia LIU Yilin LIANG Xi FU Min ZHANG Zehua 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第1期18-37,共20页
Arctic sea ice cover has decreased dramatically over the last three decades. This study quanti?es the sea ice concentration(SIC) trends in the Arctic Ocean over the period of 1979–2016 and analyzes their spatial and ... Arctic sea ice cover has decreased dramatically over the last three decades. This study quanti?es the sea ice concentration(SIC) trends in the Arctic Ocean over the period of 1979–2016 and analyzes their spatial and temporal variations. During each month the SIC trends are negative over the Arctic Ocean, wherein the largest(smallest) rate of decline found in September(March) is-0.48%/a(-0.10%/a).The summer(-0.42%/a) and autumn(-0.31%/a) seasons show faster decrease rates than those of winter(-0.12%/a) and spring(-0.20%/a) seasons. Regional variability is large in the annual SIC trend. The largest SIC trends are observed for the Kara(-0.60%/a) and Barents Seas(-0.54%/a), followed by the Chukchi Sea(-0.48%/a), East Siberian Sea(-0.43%/a), Laptev Sea(-0.38%/a), and Beaufort Sea(-0.36%/a). The annual SIC trend for the whole Arctic Ocean is-0.26%/a over the same period. Furthermore, the in?uences and feedbacks between the SIC and three climate indexes and three climatic parameters, including the Arctic Oscillation(AO), North Atlantic Oscillation(NAO), Dipole anomaly(DA), sea surface temperature(SST), surface air temperature(SAT), and surface wind(SW), are investigated. Statistically, sea ice provides memory for the Arctic climate system so that changes in SIC driven by the climate indices(AO, NAO and DA) can be felt during the ensuing seasons. Positive SST trends can cause greater SIC reductions, which is observed in the Greenland and Barents Seas during the autumn and winter. In contrast, the removal of sea ice(i.e., loss of the insulating layer) likely contributes to a colder sea surface(i.e., decreased SST), as is observed in northern Barents Sea. Decreasing SIC trends can lead to an in-phase enhancement of SAT, while SAT variations seem to have a lagged in?uence on SIC trends. SW plays an important role in the modulating SIC trends in two ways: by transporting moist and warm air that melts sea ice in peripheral seas(typically evident inthe Barents Sea) and by exporting sea ice out of the Arctic Ocean via passages into the Greenland and Barents Seas, including the Fram Strait, the passage between Svalbard and Franz Josef Land(S-FJL),and the passage between Franz Josef Land and Severnaya Zemlya(FJL-SZ). 展开更多
关键词 SEA ice concentration(SIC) Arctic Ocean SURFACE air temperature(SAT) SEA SURFACE temperature(SST) SURFACE wind(SW) INTERANNUAL and DECADAL oscillation
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ICE综合征二例
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作者 刘洪云 《铁道医学》 1987年第5期271-271,共1页
虹膜角膜内皮综合征(Irodoeorneal en dotheljal Sgndrome)简称ICE综合征。以角膜内皮异常,瞳孔弯形、虹膜异常引起视朦及眼胀眼痛为其主要临床特征的眼病,笔者曾遇2例,报告如下。例1 女、53岁,住院号46951。因右眼球胀痛,视朦三个月,于... 虹膜角膜内皮综合征(Irodoeorneal en dotheljal Sgndrome)简称ICE综合征。以角膜内皮异常,瞳孔弯形、虹膜异常引起视朦及眼胀眼痛为其主要临床特征的眼病,笔者曾遇2例,报告如下。例1 女、53岁,住院号46951。因右眼球胀痛,视朦三个月,于1985年1月24日入院,发现右眼瞳孔变形5年,无眼外伤及其他眼病史,无类似眼病家族史。体格检查、实验室检查正常。 展开更多
关键词 ice
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Predictions of future hydrological conditions and contribution of snow and ice melt in total discharge of Shigar River Basin in Central Karakoram,Pakistan 被引量:3
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作者 Javed Hassan Rijan Bhakta Kayastha +3 位作者 Ahuti Shrestha Iram Bano Sayed Hammad Ali Haleem Zaman Magsi 《Research in Cold and Arid Regions》 CSCD 2017年第6期599-612,共14页
The high mountains of Hindu-Kush Karakoram and Himalaya(HKKH) contain a large volume of snow and ice, which are the primary sources of water for the entire mountainous population of HKKH. Thus, knowledge of these avai... The high mountains of Hindu-Kush Karakoram and Himalaya(HKKH) contain a large volume of snow and ice, which are the primary sources of water for the entire mountainous population of HKKH. Thus, knowledge of these available resources is very important in relation to their sustainable use. A Modified Positive Degree Day Model was used to simulate daily discharge with the contribution of snow and ice melt from the Shigar River Basin, Central Karakoram, Pakistan. The basin covers an area of 6,921 km2 with an elevation range of 2,204 to 8,611 m a.s.l.. Forty percent of the total area is glaciated among which 20% is covered by debris and remaining 80% by clean ice and permanent snow. To simulate daily discharge, the entire basin was divided into 26 altitude belts. Remotely sensed land cover types are derived by classifying Landsat images of 2009. Daily temperature and precipitation from Skardu meteorological station is used to calibrate the glacio-hydrological model as an input variable after correlating data with the Shigar station data(r=0.88). Local temperature lapse rate of 0.0075 °C/m is used. 2 °C critical temperature is used to separate rain and snow from precipitation. The model is calibrated for 1988~1991 and validated for 1992~1997. The model shows a good Nash-Sutcliffe efficiency and volume difference in calibration(0.86% and 0.90%) and validation(0.78% and 6.85%). Contribution of snow and ice melt in discharge is 32.37% in calibration period and 33.01% is validation period. The model is also used to predict future hydrological regime up to 2099 by using CORDEX South Asia RCM considering RCP4.5 and RCP8.5 climate scenarios.Predicted future snow and ice melt contributions in both RCP4.5 and RCP8.5 are 36% and 37%, respectively. Temperature seems to be more sensitive as compared to other input variables, which is why the contribution of snow and ice in discharge varies significantly throughout the whole century. 展开更多
关键词 positive degree day factor simulated DISCHARGE daily METEOROLOGICAL variables DEBRIS covered ice clean ice
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Stratospheric Ozone-induced Cloud Radiative Effects on Antarctic Sea Ice 被引量:4
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作者 Yan XIA Yongyun HU +3 位作者 Jiping LIU Yi HUANG Fei XIE Jintai LIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第5期505-514,共10页
Recent studies demonstrate that the Antarctic Ozone Hole has important influences on Antarctic sea ice.While most of these works have focused on effects associated with atmospheric and oceanic dynamic processes caused... Recent studies demonstrate that the Antarctic Ozone Hole has important influences on Antarctic sea ice.While most of these works have focused on effects associated with atmospheric and oceanic dynamic processes caused by stratospheric ozone changes,here we show that stratospheric ozone-induced cloud radiative effects also play important roles in causing changes in Antarctic sea ice.Our simulations demonstrate that the recovery of the Antarctic Ozone Hole causes decreases in clouds over Southern Hemisphere(SH)high latitudes and increases in clouds over the SH extratropics.The decrease in clouds leads to a reduction in downward infrared radiation,especially in austral autumn.This results in cooling of the Southern Ocean surface and increasing Antarctic sea ice.Surface cooling also involves ice-albedo feedback.Increasing sea ice reflects solar radiation and causes further cooling and more increases in Antarctic sea ice. 展开更多
关键词 STRATOSPHERIC OZONE recovery ANTARCTIC sea ice cloud RADIATIVE effects ice-albedo feedback climate change
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