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Objectives: To achieve the accurate monitoring of sea ice conditions in the key area of Arctic passage, high resolution sea ice thickness is essential. However, sea ice thickness with kilometer-scale resolution cannot meet the requirement at present. Methods: Considering the relationship between sea ice thickness and image albedo, this paper tried to establish a regression model between the ICESat-2 ATL10 sea ice freeboard product and the high resolution Sentinel-2 optical image albedo by taking advantage of the intensive altimetry data of ICESat-2 along the orbit to obtain dense sea ice freeboard. Based on high resolution sea ice thickness calculated from dense freeboard with the hydrostatic equilibrium model and combined with high resolution sea ice concentration derived from Sentinel-2 image, we classified ice areas into different navigational categories according to the ice-break capability of ship and compared optimal route design at multiple spatial scales. Results: Regression models established from the ATL10 sea ice freeboard and the Sentinel-2 image albedo have good fitting accuracy. The R² of the regression model is higher than 0.5, the average deviation is less than 0.05 m, and the root mean square error of the accuracy validation is less than 0.2 m. High resolution sea ice parameters derived by the proposed method can describe the distribution of fine leads between floating ice which are difficult to be captured by low resolution sea ice parameters. Conclusions: High resolution sea ice parameters can describe the details of sea ice conditions more accurately. Therefore, the proposed high resolution inversion method of sea ice parameters can improve the capability of navigation planning for ships in Arctic passage, further improving the navigation safety. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Convolutional neural network (CNN) has been used in spaceborne global navigation satellite system-reflectometry （GNSS-R） sea ice detection, which has the advantages of simple data preprocessing and maximum retention of reflector information. However, the data sets used in previous studies of the GNSS-R CNN sea ice detection method have a small span in time and limited representativeness, and the influence of the delay-Doppler map (DDM) ratio of seawater and sea ice in the training set on the generalization ability of the method is not considered. Methods: To solve these problems, a method of screening out malformed DDM is proposed. The appropriate CNN structure and parameters are designed, and the dataset selection strategy is optimized through comparative tests of small samples. A large sample dataset from 2018 is used to evaluate the validity and reliability of the improved method in the case of large data volume and large time. Results and Conclusions: The results show that the proposed method can screen the wrong data effectively. The CNN model has high accuracy and the best generalization ability when the DDM ratio of seawater and sea ice in the training set is 1∶ 1, and the improved method is still effective and reliable in large data volume and large time span. The improved method improves the generalization ability and reliability of the CNN sea ice detection method by strengthening data quality control and optimizing the dataset selection strategy, to make it more applicable to practical application scenarios and provide a reference for studies on sea ice melting [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Reconstruction of ice flow velocity on the Antarctic Ice Sheet plays a critical role in estimating mass balance and contribution to global sea level rise. However, due to the low availability of optical satellite images before the 1990s, the time span of image pairs ranges from several years to more than ten years, leading to velocity overestimations. In this study, we correct the overestimated ice flow velocity based on the Lagrangian framework. After correction, we analyze the distribution of the overestimation values in the East Antarctic Ice Sheet (EAIS) according to the space and magnitude. Methods: We formulate a set of correction rules, including filtering points of ice flow velocity before correction and whether to retain results after correction. As a transition zone between grounded ice and ice shelf, ice flow velocity near the grounding line is one of the most important parameters of the ice sheet mass balance. In this paper, the overestimations of ice flow velocity are mainly studied from three aspects: First from different regions including inland region, grounding region and ice shelf region, then from different ocean sectors including Weddell Sea, West Indian Ocean, East Indian Ocean and Ross Sea, finally from different glaciers/ice shelves. Results: The average overestimation of ice flow velocity in EAIS is about 28 m/a. Both the grounding and ice shelf regions have larger overestimations than the inland region. The peak correction appears at ±25 km near the grounding line, and the maximum correction exceeds 300 m/a. As for ocean sectors, the overestimation of velocity is the largest in the East Indian Ocean. The average corrections of the Holmes Glacier, Ninnis Glacier, Publications Ice Shelf, and Totten Glacier in this sector exceed 50 m/a, much larger than that of EAIS. Conclusions: This paper shows that only a very small proportion of ice velocity points can meet the correction rules. The points show differences in regional distribution and they are concentrated mainly in the fast-flowing areas such as glaciers and ice shelves. Especially at the grounding zone and ice front areas of ice shelves, the ice flow velocity can be greatly overestimated. By analyzing the corrections and ice flow velocities in different ocean sectors, we found that the spatial acceleration trend of velocity in the East Indian Ocean is obvious and may be related to the interaction between the ocean and the ice shelves. The distribution of corrections varies among different ice shelves and glaciers. For example, Amery Ice Shelf has a larger correction at the confluence of three upstream glaciers, while Shirase Glacier has a larger correction in the inland region. The correction results in this paper have been applied to historical ice flow velocity products for East Antarctica from 1960s to 1980s. The overestimation correction of ice velocity is important for reducing the uncertainty in estimation and forecasting the contribution of Antarctic mass loss to the global sea level rise. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global warming has led to the increase of sea ice melting. It is highly possible for the Arctic Passage to achieve continuous navigation in summer in recent decades. The key position of the strategic fulcrum port of the Arctic Passage has become increasingly prominent. Drawing on the relevant concepts of strategy, the authors define the connotation and scope of the strategic fulcrum port of the Arctic Passage, and analyze the current situation and layout of the strategic fulcrum port of the Arctic Passage in order to contribute to the study of polar governance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: As an emerging airborne remote sensing system, unmanned aerial vehicle (UAV) falls into multiple categories with various payloads, such as the multi ⁃ rotor and fixed ⁃ wing ones. Despite the harsh climatic condition, UAV is widely used in many Antarctic fields of basic and applied science, which still lacks a comprehensive and systematic literature review. Methods: We firstly discuss the special impact of Antarctic environmental conditions (meteorology, electromagnetic field, light, etc.) on the UAV operation. A comprehensive literature retrieval is subsequently presented on the current application of UAV in Antarctic research and expedition. We sort out 104 papers according to the time of publication, main journals, study areas, nations, and institutions. Representative literature is reviewed in seven application areas, including aeromechanics, atmosphere, sea ice and iceberg, glacier, geomorphology and geomagnetism, ecology-vegetation as well as ecology-animals. We retrospect the development and achievement of UAVs applications in the Chinese national Antarctic research and summarize the limitations of the research on the application of UAV in Antarctica. Results: A number of environmental factors need to be considered before the UAV missions, such as the meteorological conditions, electromagnetic field, solar radiations, and flight regulations. According to the review, half of the literature belongs to the journal paper, mostly in Polar Biology, Polar Science, and Remote Sensing. The earliest UAV research in Antarctica was published in 2004, followed by a productive period of International Polar Year in 2008. The first-tier countries including the USA, Australia, and Germany, led the progress in the research on UAVs in Antarctica. Meanwhile, the dominant role of top universities stood out via various collaborations. The UAV can also be classified into multiple categories according to the payload, such as the industrial⁃ or consumer-grade optical cameras, radiosonde, synthetic aperture radar, and light detecting and ranging （LiDAR), among which consumer-grade camera is widely used in Antarctic investigations. China􀆳s Antarctic expedition team initiated the Antarctic UAV program in 2007 and had carried out at least 18 flight missions by 2020. The flights covered Zhongshan Station, The Great Wall Station, Inexpression Island, and the inland ice sheet, from which the collected data were employed to support the glaciological, geomorphic, and biological studies. Conclusions: The UAV remote sensing, as the essential technology in the “Air ⁃Space ⁃Ground” polar observation system, has been increasingly upgraded in the recent decade. The flight experiments covered the primary research topics and research fields in Antarctic science. In general, the application and development of Antarctic UAV in China lie in the second tier, falling behind the USA and Australia. In the end, according to the current development of Antarctic UAV in China, this paper provides guidance for China's Antarctic expedition team in the future: (1) Develop new UAV models; (2) Make breakthroughs in the battery technology; (3) Couple multiple sensors; (4) Encourage trans ⁃disciplinary collaboration; (5) Pro-mote foreign communication and sharing; (6) Participate in the international management. [ABSTRACT FROM AUTHOR]

Based on the installation requirements of a ice detector on airplanes, a three-dimensional numerical simulation method is used to simulate the airfield and droplet impact characteristic around the nose. Dangerous point is adopted to analyze the appropriate installation location of ice detector by demarcating the shadow area and increased concentration area of water droplet. Droplet collective characteristic and icing characteristic of ice detector are analyzed and compared with that of airplane’s main windward components. Results show that the maximum collection coefficient, icing intensity and icing degree of the probe surface are not lower than the corresponding characteristics of the main windward components of the aircraft, which meets the early warning requirements of ice detection. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Sea ice concentration (SIC), which is defined as the proportion of a given area of ocean that is covered by ice, is a significant parameter for Arctic sea ice and climate change, an important input for regional climate model and numerical weather prediction model. The passive microwave sensors are able to penetrate the atmosphere and clouds, regardless of observation time, and their data is commonly used to retrieve SIC. Passive microwave obtained from the microwave radiation imager (MWRI) aboard on the Chinese Fengyun‑3 (FY ‑3) series satellites can be used to extract polar SIC. However, the study on its accuracy is limited. Methods: This paper focuses on the application of MWRI to Arctic SIC estimation accuracy, and compares the SIC obtained using special sensor microwave imager sounder (SSMIS), MWRI and advanced microwave scanning radiometer 2 (AMSR2) data, and utilizes Bootstrap, NASA Team (NT), fully constrained least squares (FCLS), Enhanced NASA Team (NT2) and Arctic radiation and turbulence interaction study (ARTIST) sea ice (ASI) methods with the in‑situ data. Results: Validation results show that MWRI has the smallest root mean square error (RMSE) at different spatial resolution (20.4%- 24.4%). FCLS performed better than the other five algorithms for three passive microwave data because the error was considered during the SIC retrieve, the SIC was constrained with non‑negative constrain, and numerical optimization was used to solved the SICs. In addition, MWRI performs well in summer (17.9%-23.0%) and winter (11.2%-17.8%).Conclusions: MWRI has relatively stable performance and a great potential for sea ice monitoring. Uncertainty also exists in evaluation, such as the uncertainty of accuracy of in ‑situ data in Arctic and tie points. Furthermore, scale difference between multi ‑source data could also induce the uncertainty of validation. [ABSTRACT FROM AUTHOR]

Objectives When polar ships sailing in polar regions, extremely complex ice resistance not only poses structural threats to ships, but also poses new challenges for ship maneuverability, especially when the ship is turning in a level ice zone. In contrast, recent studies have mainly focused on ship-ice interaction with less consideration for the effects of fluids on ice loading.Methods Using the nonlinear finite element method and based on the proper ice material and reasonable coupling failure mode, the complex, strong and nonlinear interaction between ice and ship during turning motion is studied. At the same time, the fluid structure interaction method is used to consider the influence of fluid on ship-ice interaction.Results The validity and reliability of the simulation are determined via the numerical results and empirical formulae. The longitudinal, widthwise and vertical ice resistance of the ship are compared with or without fluid conditions. It is found that the ice load has a noticeable increase in three degrees of freedom when the effects of fluid are considered.Conclusions Considering the influence of fluid on ice resistance in the ship's ice-breaking movement can effectively ensure the safety of the ship and accurately predict the ice resistance when turning.

Objectives: Morphology of polar sea ice changes continuously under the influences of external driving forces, e.g., wind, flow and waves. Observations and change regularity analysis on morphology of polar sea ice not only is helpful for the optimization of sea ice thermodynamics numerical simulation and the inversion of sea ice thickness based on roughness parameters, but also provide distinct importance for under⁃ standing the response of polar sea ice morphology to climate change. Methods: Based on the undulations profiles of sea ice bottom in Northwestern Weddell Sea measured by the helicopter⁃borne electromagnetic⁃ induction bird (EM⁃bird) system during the winter of 2006, this paper establishes a nonlinear statistical optimal model with the cutoff draft as the identified variable to separate the ridge keels and local undulations on sea ice bottom. Then, the keel morphology parameters and correlation between the keel draft and frequency are statistically analyzed. Finally, a new parameter T is hatched to assess the correlation between the ridge sail height and keel draft.Results: The results suggest that the optimal cutoff draft is 3.8 m and the keel spacing is the main factor affecting the ridging intensity. Despite marked sea ice deformation in different regions in Northwestern Weddell Sea, morphology changes of the keel are not evident. There is a good log correlation between draft and frequency of the keel, which vividly describes morphology and distribution of the keel. The newly hatched parameter T has a significant linear correlation with keel depth (r=0.93). Conclusions: The newly proposed modeling method can separate the keel from sea ice bottom undulations more accurately, which provides a new theoretical reference for morphological correlation analysis between surface and bottom of sea ice, and the inversion of sea ice thickness and bottom draft from its surface height. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sea ice thickness is one of the most important and inaccessible parameters of sea ice, which is of great significance to marine disaster warning and climate change. In this paper, 10 multi-source ( Sentinel-2, Landsat-8, Landsat-7) medium and high-resolution images from January to March 2018 are selected to monitor the sea ice in Liaodong Bay of the Bohai Sea. The sea and land segmentation is based on the normalized water body index. By analyzing the spectral characteristics of sea water and sea ice, the sea ice region is extracted by the maximum likelihood method, and the sea ice thickness is inverted by the exponential albedo model. The inversion results are compared with the ice thickness calculated by Zubov empirical model. The correlation coefficient is 0. 884, which proves the feasibility of medium high resolution optical remote sensing data in sea ice thickness inversion. At the same time, taking advantage of the medium and high resolution remote sensing data, using ice thickness information to extract sea ice types and estimate sea ice resources, it can provide reference for the prevention and mitigation of sea ice disaster and the utilization of sea ice resources in the Bohai Sea. [ABSTRACT FROM AUTHOR]

In order to improve the estimation accuracy of freeboard of Antarctic sea ice， this paper combined CryoSat⁃2 altimeter data, ASPeCt ship observational data and IceBridge airborne altimeter data to explore the optimal parameters for freeboard estimation using the minimum method, as well as analyzed spatiotemporal variation of sea ice freeboard from May to October，2011−2017 in the Weddell sea. The result indicates that the optimal parameter scheme for retrieving freeboard is to apply the average of the lowest 5% measurements as local sea surface height after eliminating the gross data using 0.8 times standard deviation within 10 km segment. Over the past seven years, sea ice freeboard in the Weddell sea presents a slightly thinning trend, and monthly average freeboard ranges from 17.9 cm to 27.4 cm. The distribution of sea ice freeboard of the Weddell sea is characterized by the thick sea ice located in the west Weddell sea and near the Antarctic Peninsula, while thin sea ice distributed in the east Weddell sea. This study could be beneficial for further studying the response of the Antarctic sea ice thickness to climate change. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the significant impacts that polar ice has on the climate of the mid-low latitudes,this paper mainly analyses the effects and possible mechanism of Arctic sea ice on the precipitation in the main flood season of the Yangtze River basin by statistical methods such as Singular Value Decomposition. The precipitation data is collected from 116 rainfall stations in the Yangtze River basin and the sea ice data is provided by the United States National Snow and Ice Data Center (NSIDC),both periods are 1979-2017. The results show as follows:In winter and spring,when ice area in the Barents Sea and Okhotsk Sea was more than the average and that in the Beaufort Sea was less than the average,then summer precipitation in upper and middle reaches of the Yangtze River,the upper reaches of the Hanjiang River and the Yalong River increased;When winter-spring ice area in the northern part of the Arctic Archipelago,Chukchi Sea and Laptev Sea was much,summer precipitation in the Dongting Lake and Poyang Lake was much too,but it was less in the upper reaches of the Jialing River and Hanjiang River; and vice versa. The possible mechanism is that the sea ice variation in key regions in winter and spring stimulates atmospheric energy fluctuation by affecting turbulent heat flux. This fluctuation propagates to East Asia in the form of atmospheric wave trains and affects the summer atmospheric circulation and water vapor transport in East Asia,thus indirectly affecting precipitation of the Yangtze River basin in the main flood season. Based on the multivariate regression method,four prediction models of precipitation in the main flood season are built by taking the sea ice area in key region as predictors. The models have obvious fluctuation on quantitative precipitation prediction,but it has a relatively good effect on precipitation trend prediction. [ABSTRACT FROM AUTHOR]

Based on multisensory data? including sptical and thermal images from MODIS» and dualpolarization SAR image from RadarSat-2, sea ice in Beaufort Sea is classified, sea ice leads are identified and accuracy of the result is also evaluated. Experiment shows that thermal images from MODIS is only useful in extracting lead area with coarse resolution, while the high-resolution SAR image could provide more information on sea ice type in lead. However, overlay of signals from different ice type largely reduces the overall accuracy from supervised classification of RadarSat-2 image. Therefore ,decision tree is established to incorporate multisensory data. Characteristics of different ice types and leads is analyzed and utilized in decision tree to detect ice leads in different stages of development. Validation shows that overall accuracy of the result from decision tree is 14. S% higher than that from supervised classification. The sequential structure composed of various development stages of ice leads is confirmed in Sentinel-2 images. The result might facilitate accurate calculation of heat flux and ice production, as well as ship navigation with detail ice type in lead [ABSTRACT FROM AUTHOR]

A spaceborne sea ice edge detecting method is developed using the Global Navigation Satellite System reflectometry (GNSS R). The difference of reflected signal delay map (DM) were observed in the satellite reflected signal of sea ice relative to those of sea water. Combined with specular reflection point location, it can be used to detect sea ice edge. An adaptive threshold algorithm is employed to process TDS1 satellite data for the available DM. The curve of the DM derivatives with the specular reflection point position is obtained. Through comparing DM observable based detection results with sea ice extent data analyzed by multisensory, the delay distance of the DM effective area, the peak of the correlation power, and the normalized mean square error can be used for sea ice edge detection. The method using GNSSR is feasible to detect sea ice edge in spaceborne environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Changes in both the area and thickness of Arctic sea ice are significantly influenced by global climate change the rapid decline in Arctic sea ice during the summer of 2007 is analyzed empirically in our research. Sea ice thickness can be retrieved from the sea ice freeboard heights. As ICESat/GLAS (ice, cloud and land elevation satellite/geoscience laser altimeter system) provide high-precision sea ice elevation information, therefore we could extract the freeboard heights of the Arctic sea ice from ICESat/GLAS datasets spanning from 2003 to 2008 to analyze seasonal and inter-annual variation in Arctic sea ice. The results show that the Arctic sea ice freeboard heights have been decreasing during 2003-2008, especially in the summer of 2007. Systematic deviations in the retrieved results are discussed and analyzed based on the ULS (Upward Looking Sonar) field data. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, the passive microwave remote sensing data has become one of the important means to extract the sea ice concentration (SIC) in polar regions. The SIC products, however, have different degree of errors which will cause the calculated total sea-ice extent and area uncertain. This paper simulated the error of the SIC product by using Monte Carlo method and analyzed the stochastic simulation images. Several indicators such as the coefficient of variation were used to quantify the uncertainty of total-extent and total-area caused by random error. This study revealed: that when the error of SIC product is small, the uncertainty of the total-extent is larger than that of the total-area; whereas, when the error of SIC product is large, the uncertainty of the total-are is larger than that of the total-extent; and the uncertainty of both total-extent and total-area is related to the resolution and season, namely, the higher the resolution is, the smaller the uncertainty would be, and the uncertainty in winter is smaller than that in summer. [ABSTRACT FROM AUTHOR]

Due to the tidal effect, sea ice in Polar Regions moves vertically along with the sea level. The elevation of the sea ice's upper surface can be detected by a GPS receiver, and sea level can be measured by tide observations. Thereupon, if we can provide the thickness of the snow cover over the sea ice, and the densities of snow and sea ice, then, according to the principle of hydrostatic balance, thickness of the sea ice can be derived by a combination of the GPS and tide observations. The experiment conducted by the 28th Chinese National Antarctic Expedition at Zhongshan Station in Antarctica during September 22, 2012 to November 9 indicates that the sea ice thickness can be estimated in centimeter-level accuracy by this approach. Compares to the measurements made by drilling holes, the maximum difference is 8.9 centimeters, the root mean square of the different values is 5.4 centimeters. [ABSTRACT FROM AUTHOR]

In consideration of the Antarctic special environment, a new sea-ice extraction method of u-sing the 0.86 µm. and 1.24 µm wave bands of MODIS is proposed, based on the Normalize Difference Snow Index (NDSI). It can extract the sea ice under the clear sky and thin cloud condition respectively, which largely improve the efficiency and spatial resolution of Antarctic sea-ice monitoring. The new method is used to obtain the monthly sea ice images in the whole Antarctica of recent years. Then, combining the AMSR-E data, the change monitoring of Antarctic sea ice is executed. It indicates that, from 2002 to 2010, both the Antarctic sea-ice extent and sea-ice area reach the minimums in February, with the averages are 3.17 x 106 km² and 2.42 x 106 km² respectively. And the maxi-mums appear in September, with the averages are 18.440 x 106 km² and 16. 60 x 106 km². The inter annual change of Antarctic sea ice can be divided to three periods: the flat period of the year from 2002 to 2004, the reduced period of 2005 to 2007, and the increased period of 2008 to 2010. It verifies the 20 years cycle of Antarctic sea ice in the inter annual change. The change trend of the whole Antarctic sea ice is not obvious in the recent nine years [ABSTRACT FROM AUTHOR]

A new icebreaking structure was designed to decrease large forces of ice floes on offshore structures in shallow waters. The structure was used to break the large-area ice floes into small pieces to reduce the ice forces on the protected maritime structures at the back by breaking the floating ice in bending. A column pile was taken as an example to inspect the protection effect of the new icebreaking structure. A series of physical model tests were conducted to simulate the crushing loads of ice floes and the impact forces of broken ice pieces on the pile, respectively. Additionally, the level ice load on the structure was measured and the test of sliding and overturning itself was carried Out to determine the stability of the icebreaking structure. A relative coefficient was used to quantify the protection effect. The influence of relative water level and relative distance on the protection effect was analyzed. The test results show that the stability of the structure is good, and protection effect becomes increasingly apparent while the water level is lower than the summit of it. Due to the positive effect, the new icebreaking structure has a broad prospect in shallow icy waters. [ABSTRACT FROM AUTHOR]