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| 1 | 水库冰气泡含量和密度对探地雷达测厚的影响分析(英文)显示文摘在水库现场试验了RIS K2型探地雷达探测水库冰厚度的能力,试验时所用天线频率为600MHz;同步钻孔测量雷达探测处的冰厚度;以及在一个点上取样测试分析冰晶体、冰内气泡和冰密度。试验时冰面积雪厚度0.03-0.05m,冰层上部有0.24m粒状冰,其下均为柱状冰;冰内气泡含量呈表层高底层低分布;冰密度随气泡含量变化;冰厚度在平面内不均一。通过探测厚度和实测厚度的对比分析以及气泡含量对介电系数影响的理论分析,建立了积雪、粒状冰和柱状冰三层介质模型,获取雷达波在冰内的理论传递时间。结果发现:能够利用等效介电常数或等效传播速度评价雷达波传递时间,结冰期冰层1/3深度处的对应介电常数或传递速度可以作为等效值;另外因冰内大气泡造成的理论传递时间大于雷达探测时间,其差值随理论传递时间或冰厚的增加呈非线性增加。 | 李志军 贾青 张宝森 Leppranta Matti 卢鹏 黄文峰 | 2010 | Applied Geophysics2010，7，2： | 11 |
| 2 | Albedo of Coastal Landfast Sea Ice in Prydz Bay,Antarctica:Observations and Parameterization显示文摘The snow/sea-ice albedo was measured over coastal landfast sea ice in Prydz Bay, East Antarctica(off Zhongshan Station)during the austral spring and summer of 2010 and 2011. The variation of the observed albedo was a combination of a gradual seasonal transition from spring to summer and abrupt changes resulting from synoptic events, including snowfall, blowing snow, and overcast skies. The measured albedo ranged from 0.94 over thick fresh snow to 0.36 over melting sea ice. It was found that snow thickness was the most important factor influencing the albedo variation, while synoptic events and overcast skies could increase the albedo by about 0.18 and 0.06, respectively. The in-situ measured albedo and related physical parameters(e.g., snow thickness, ice thickness, surface temperature, and air temperature) were then used to evaluate four different snow/ice albedo parameterizations used in a variety of climate models. The parameterized albedos showed substantial discrepancies compared to the observed albedo, particularly during the summer melt period, even though more complex parameterizations yielded more realistic variations than simple ones. A modified parameterization was developed,which further considered synoptic events, cloud cover, and the local landfast sea-ice surface characteristics. The resulting parameterized albedo showed very good agreement with the observed albedo. | Qinghua YANG Jiping LIU Matti LEPPRANTA Qizhen SUN Rongbin LI Lin ZHANG Thomas JUNG Ruibo LEI Zhanhai ZHANG Ming LI Jiechen ZHAO Jingjing CHENG | 2016 | Advances in Atmospheric Sciences2016，33，5： | 7 |
| 3 | MODIS-based Daily Lake Ice Extent and Coverage dataset for Tibetan Plateau显示文摘The Tibetan Plateau houses numerous lakes,the phenology and duration of lake ice in this region are sensitive to regional and global climate change,and as such are used as key indicators in climate change research,particularly in environment change comparison studies for the Earth three poles.However,due to its harsh natural environment and sparse population,there is a lack of conventional in situ measurement on lake ice phenology.The Moderate Resolution Imaging Spectroradiometer(MODIS)Normalized Difference Snow Index(NDSI)data,which can be traced back 20 years with a 500 m spatial resolution,were used to monitor lake ice for filling the observation gaps.Daily lake ice extent and coverage under clear-sky conditions was examined by employing the conventional SNOWMAP algorithm,and those under cloud cover conditions were re-determined using the temporal and spatial continuity of lake surface conditions through a series of steps.Through time series analysis of every single lake with size greater than 3 km2 in size,308 lakes within the Tibetan Plateau were identified as the effective records of lake ice extent and coverage to form the Daily Lake Ice Extent and Coverage dataset,including 216 lakes that can be further retrieved with four determinable lake ice parameters:Freeze-up Start(FUS),Freeze-up End(FUE),Break-up Start(BUS),and Break-up End(BUE),and 92 lakes with two parameters,FUS and BUE.Six lakes of different sizes and locations were selected for verification against the published datasets by passive microwave remote sensing.The lake ice phenology information obtained in this paper was highly consistent with that from passive microwave data at an average correlation coefficient of 0.91 and an RMSE value varying from 0.07 to 0.13.The present dataset is more effective at detecting lake ice parameters for smaller lakes than the coarse resolution passive microwave remote sensing observations.The published data are available in http://gffzz324c53c67c144612s6ouxbkkbubxb6qwn.ffgz.tsg.suse.edu.cn/repository/uuid:fdfd8c76-6b7c-4bbf-aec8-98ab199d9093 and http://gffzzc14d9fd2be724b39h6ouxbkkbubxb6qwn.ffgz.tsg.suse.edu.cn/dataSet/handle/744. | Yubao Qiu Pengfei Xie Matti Leppäranta Xingxing Wang Juha Lemmetyinen Hui Lin Lijuan Shi | 2019 | Big Earth Data2019，3，2： | 7 |
| 4 | Comparisons of passive microwave remote sensing sea ice concentrations with ship-based visual observations during the CHINARE Arctic summer cruises of 2010–2018显示文摘In order to apply satellite data to guiding navigation in the Arctic more effectively,the sea ice concentrations(SIC)derived from passive microwave(PM)products were compared with ship-based visual observations(OBS)collected during the Chinese National Arctic Research Expeditions(CHINARE).A total of 3667 observations were collected in the Arctic summers of 2010,2012,2014,2016,and 2018.PM SIC were derived from the NASA-Team(NT),Bootstrap(BT)and Climate Data Record(CDR)algorithms based on the SSMIS sensor,as well as the BT,enhanced NASA-Team(NT2)and ARTIST Sea Ice(ASI)algorithms based on AMSR-E/AMSR-2 sensors.The daily arithmetic average of PM SIC values and the daily weighted average of OBS SIC values were used for the comparisons.The correlation coefficients(CC),biases and root mean square deviations(RMSD)between PM SIC and OBS SIC were compared in terms of the overall trend,and under mild/normal/severe ice conditions.Using the OBS data,the influences of floe size and ice thickness on the SIC retrieval of different PM products were evaluated by calculating the daily weighted average of floe size code and ice thickness.Our results show that CC values range from 0.89(AMSR-E/AMSR-2 NT2)to 0.95(SSMIS NT),biases range from−3.96%(SSMIS NT)to 12.05%(AMSR-E/AMSR-2 NT2),and RMSD values range from 10.81%(SSMIS NT)to 20.15%(AMSR-E/AMSR-2 NT2).Floe size has a significant influence on the SIC retrievals of the PM products,and most of the PM products tend to underestimate SIC under smaller floe size conditions and overestimate SIC under larger floe size conditions.Ice thickness thicker than 30 cm does not have a significant influence on the SIC retrieval of PM products.Overall,the best(worst)agreement occurs between OBS SIC and SSMIS NT(AMSR-E/AMSR-2 NT2)SIC in the Arctic summer. | Yuanren Xiu Zhijun Li Ruibo Lei Qingkai Wang Peng Lu Matti Leppäranta | 2020 | Acta Oceanologica Sinica2020，39，9： | 6 |
| 5 | Model simulations of the annual cycle of the landfast ice thickness in the East Siberian Sea显示文摘The annual cycle of the thickness and temperature of landfast sea ice in the East Siberian Sea has been examined using a one-dimensional thermodynamic model. The model was calibrated for the year August 2012–July 2013, forced using the data of the Russian weather station Kotel'ny Island and ECMWF reanalyses. Thermal growth and decay of ice were reproduced well, and the maximum annual ice thickness and breakup day became 1.64 m and the end of July. Oceanic heat flux was 2 W.m–2 in winter and raised to 25 W.m–2 in summer, albedo was 0.3–0.8 depending on the surface type(snow/ice and wet/dry). The model outcome showed sensitivity to the albedo, air temperature and oceanic heat flux. The modelled snow cover was less than 10 cm having a small influence on the ice thickness. In situ sea ice thickness in the East Siberian Sea is rarely available in publications. This study provides a method for quantitative ice thickness estimation by modelling. The result can be used as a proxy to understand the sea ice conditions on the Eurasian Arctic coast, which is important for shipping and high-resolution Arctic climate modelling. | YANG Yu Matti Leppranta LI Zhijun Bin Cheng ZHAI Mengxi Denis Demchev | 2015 | Advances in Polar Science2015，26，2： | 5 |
| 6 | 乌梁素海湖冰晴天反照率日变化特征的统计模型比较和分析显示文摘乌梁素海湖冰晴天反照率日变化具有双峰特征,利用当地太阳高度角同经纬度和儒历的关系,归一化到北京时,依此表达湖冰反照率日变化规律.基于具有指数函数形式的拉普拉斯、高斯、耿贝尔和柯西4种概率密度分布函数建立线性组合模型,对日出后到日落前太阳高度角大于5°时段内的反照率日变化数据进行拟合,发现拉普拉斯密度分布函数组合是最佳统计模型.它既能拟合太阳高度角大于5°时间范围内反照率日变化曲线的双峰特征,又能反映太阳高度角大于15°时间范围内反照率日变化曲线双峰之间的U型分布.该模型不仅形式简单,而且意义明确:尺度参数约为日长的一半,双峰位置与日出时刻关系密切;同时能体现2个反照率峰值的不对称性.为发展不同地区湖冰反照率日变化参数化方案奠定基础. | 汤明光 李志军 卢鹏 曹晓卫 李国玉 Lepp ranta Matti Arvola Lauri 石利娟 | 2020 | 湖泊科学2020，32，6： | 4 |
| 7 | Mobility of arsenic, cadmium and zinc in a multi-element contaminated soil profile assessed by in-situ soil pore water sampling, column leaching and sequential extraction显示文摘 | Luke Beesley Eduardo Moreno-Jiménez Rafael Clemente Nicholas Lepp Nicholas Dickinson | 2009 | Environmental Pollution2009，，1： | 2 |
| 8 | Spatial and temporal evolution of landfast ice near Zhongshan Station, East Antarctica, over an annual cycle in 2011/2012显示文摘Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early December 2011. Landfast ice partly broke in late January, 2012 after a strong cyclone. Open water was refrozen to form new ice cover in mid-February, and then FYI and SYI co-existed in March with a growth rate of 0.8 cm/d for FYI and a melting rate of 2.7 cm/d for SYI. This difference was due to the oceanic heat flux and the thickness of ice,with weaker heat flux through thicker ice. From May onward, FYI and SYI showed a similar growth by 0.5 cm/d.Their maximum thickness reached 160.5 cm and 167.0 cm, respectively, in late October. Drillings showed variations of FYI thickness to be generally less than 1.0 cm, but variations were up to 33.0 cm for SYI in March,suggesting that the SYI bottom was particularly uneven. Snow distribution was strongly affected by wind and surface roughness, leading to large thickness differences in the different sites. Snow and ice thickness in Nella Fjord had a similar 'east thicker, west thinner' spatial distribution. Easterly prevailing wind and local topography led to this snow pattern. Superimposed ice induced by snow cover melting in summer thickened multi-year ice,causing it to be thicker than the snow-free SYI. The estimated monthly oceanic heat flux was ~30.0 W/m2 in March–May, reducing to ~10.0 W/m2 during July–October, and increasing to ~15.0 W/m2 in November. The seasonal change and mean value of 15.6 W/m2 was similar to the findings of previous research. The results can be used to further our understanding of landfast ice for climate change study and Chinese Antarctic Expedition services. | Jiechen Zhao Qinghua Yang Bin Cheng Matti Lepp?ranta Fengming Hui Surui Xie Meng Chen Yining Yu Zhongxiang Tian Ming Li Lin Zhang | 2019 | Acta Oceanologica Sinica2019，38，5： | 2 |
| 9 | A lake ice phenology dataset for the Northern Hemisphere based on passive microwave remote sensing显示文摘Lake ice phenology(LIP)is an essential indicator of climate change and helps with understanding of the regional characteristics of climate change impacts.Ground observation records and remote sensing retrieval products of lake ice phenology are abundant for Europe,North America,and the Tibetan Plateau,but there is a lack of data for inner Eurasia.In this work,enhanced-resolution passive microwave satellite data(PMW)were used to investigate the Northern Hemisphere Lake Ice Phenology(PMW LIP).The Freeze Onset(FO),Complete Ice Cover(CIC),Melt Onset(MO),and Complete Ice Free(CIF)dates were derived for 753 lakes,including 409 lakes for which ice phenology retrievals were available for the period 1978 to 2020 and 344 lakes for which these were available for 2002 to 2020.Verification of the PMW LIP using ground records gave correlation coefficients of 0.93 and 0.84 for CIC and CIF,respectively,and the corresponding values of the RMSE were 11.84 and 10.07 days.The lake ice phenology in this dataset was significantly correlated(P<0.001)with that obtained from Moderate Resolution Imaging Spectroradiometer(MODIS)data-the average correlation coefficient was 0.90 and the average RMSE was 7.87 days.The minimum RMSE was 4.39 days for CIF.The PMW is not affected by the weather or the amount of sunlight and thus provides more reliable data about the freezing and thawing process information than MODIS observations.The PMW LIP dataset pro-vides the basic freeze-thaw data that is required for research into lake ice and the impact of climate change in the cold regions of the Northern Hemisphere.The dataset is available at http://gffzza4c772bdab62464fh6ouxbkkbubxb6qwn.ffgz.tsg.suse.edu.cn/10.11922/sciencedb.j00076.00081. | Xingxing Wang Yubao Qiu Yixiao Zhang Juha Lemmetyinen Bin Cheng Wenshan Liang Matti Leppäranta | 2022 | Big Earth Data2022，6，4： | 2 |
| 10 | Modelling on seasonal lake ice evolution in central Asian arid climate zone: a case study显示文摘The seasonal cycle of ice thickness and temperature in Lake Wuliangsuhai,a typical shallow lake in the central Asian arid climate zone,was simulated using the HIGHTSI model and the MERRA-2 data as the meteorological forcing.The average ice growth rate was 0.64 cm·d^(−1) and −1.65 cm·d^(−1) for the growth and melting stage of the ice cover,respectively.The ice thickness agreed well with the field observations conducted in winter 2017,with a correlation coefficient of 0.97.The ice temperature field also agreed with observations in both daily variations and the vertical profile,and a better agreement in the daily amplitude and profile shape of ice temperature could be achieved if field data on physical properties of snow cover andmelting ice were available.This study proved the feasibility of both the HIGHTSI model and the MERRA-2 data for modeling the ice cover evolution in Lake Wuliangsuhai,providing a basis for a deep insight into the difference of lake ice evolution between central Asian arid climate zone and polar/sub-polar regions. | LU Peng Bin CHENG Matti LEPPÄRANTA LI Zhijun | 2021 | Advances in Polar Science2021，32，4： | 2 |
| 11 | 封冻期高纬度湖泊底层溶解氧浓度的变化特征分析显示文摘溶解氧是评价水质好坏的重要参数,对水中生物的生存状况影响很大,而封冻后的湖泊,水中溶解氧的变化更加值得关注.对于高纬度地区的湖泊冬季封冻时间比较长,光照时间比较短,湖泊中的溶解氧与水温相对封冻前变化比较大.通过对2013—2014冬季芬兰Valkea-Kotinen湖封冻期底层水中的溶解氧浓度与水温数据的研究,讨论了在整个封冻期该湖3-6m深度溶解氧浓度的时空变化情况,其随着封冻时间持续下降,在融化前有比较大的跃升.得到了不同深度的溶解氧浓度与水温变化的回归方程,在最底层溶解氧浓度与水温的拟合优度最差,因此在最底层影响溶解氧浓度的变化因素更为复杂一些,不仅仅受水温变化的影响.通过对溶解氧的功率谱分析,可见在3m深度的周期是24h,但是4-6m深度日变化周期并不明显.通过对底部无氧层的分析,发现在封冻后的第36天,底部6m深度的溶解氧耗尽,得到了底部无氧层厚度随冰封持续时间变化的对数表达式. | 柏钦玺 李志军 冯恩民 李国玉 Lauri Arvola Matti Lepprant | 2018 | 数学的实践与认识2018，48，1： | 2 |
| 12 | Residents’ attitudes towards tourism in Bigodi village, Uganda显示文摘 | Andrew Lepp | 2006 | Tourism Management2006，，3： | 2 |
| 13 | Residents' attitudes towards tourism in Bigodi village, Uganda 显示文摘 | LEPP A | 2007 | Tourism Management2007，28，3： | 1 |
| 14 | Depression biases the recognition of emotionally neutral faces显示文摘 | Lepp(a)nen JM Milders M Bell JS | 2004 | Psychiat Res2004，128，2： | 1 |
| 15 | Pedestrian navigation based on inertial sensors,indoor map,and WLAN signals显示文摘 | Lepp?koski H Collin J Takala J | | 0，，03： | 1 |
| 16 | Tourist roles, perceived risk and international tourism 显示文摘 | Lepp A Gibson H | 2003 | Annals of Tourism Research2003，30，3： | 1 |
| 17 | The potential of tree-ring analysis for monitoring heavy metal pollution patterns显示文摘 | Lepp N W | 1975 | Environmental Pollution1975，，9： | 1 |
| 18 | Image and perceived risk: A study of Uganda and its official tourism website 显示文摘 | Lepp A Gibson H Lane C | 2011 | Tourism Management2011，32，3： | 1 |
| 19 | Effects of high-impact exercise on bone mineral density: a ran- domized controlled trial in premenopausal women 显示文摘 | Vainionp A Korpelainen R Lepp Luoto J | 2005 | Osteoporosis International2005，16，2： | 1 |
| 20 | The relationship between cell phone use,academic performance,anxiety,and Satisfaction with Life in college students显示文摘 | Lepp A Barkley JE Karpinski AC | 2014 | Comput Human Behav2014，31，0： | 1 |
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