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Variations in evaporation from water surfaces along the margins of the Badain Jaran Desert over nearly 60 years and influencing factors
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作者 Li-juan Wang Zhe Wang +3 位作者 Gao-lei Jiang Zhen-long Nie Jian-mei Shen Sheng-hua Song 《Journal of Groundwater Science and Engineering》 2024年第3期253-263,共11页
Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evapor... Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evaporation from water surfaces and identified the dominant controlling factors.Methods used included linear trend analysis,linear tendency estimation,the departure method,the rank correlation coefficient-based method,and Multiple Linear Regression(MLR).Results indicate notable spatiotemporal differences in evaporation distribution and evolution.Spatially,average annual evaporation exhibited a pronounced altitude effect,decreasing at a rate of about 8.23 mm/m from east to west with increasing altitude.Temporally,annual evaporation showed significant upward trends after 1996 at the northeastern(Guaizi Lake)and western(Dingxin)margins,with rates of 132 mm/10a and 105 mm/10a,respectively.Conversely,along the northwestern(Ejina Banner)and southern(Alxa Right Banner)margins of the desert,an evaporation paradox was observed,with annual evaporation trending downward at rates of 162 mm/10a and 187 mm/10a,respectively,especially after 1987.The dominant factors controlling evaporation varied spatially:Average annual temperature and relative humidity influended the western margin(Dingxin),average annual temperature was the key factor for the northeastern margin(Guaizi Lake),and average wind speed was crucial for the northern(Ejina Banner)and southern(Alxa Right Banner)margins. 展开更多
关键词 Evaporation from water surface Evaporation paradox Dominant controlling factor Variation trend
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Surface Topography of Fine-grained ZrO_2 Ceramic by Two-dimensional Ultrasonic Vibration Grinding
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作者 丁爱玲 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第6期1162-1165,共4页
The surface quality of fine-grained ZrO2 engineering ceramic were researched using 270# diamond wheel both with and without work-piece two-dimension ultrasonic vibration grinding(WTDUVG). By AFM images, the surface ... The surface quality of fine-grained ZrO2 engineering ceramic were researched using 270# diamond wheel both with and without work-piece two-dimension ultrasonic vibration grinding(WTDUVG). By AFM images, the surface topography and the micro structure of the two-dimensional ultrasonic vibration grinding ceramics were especially analyzed. The experimental results indicate that the surface roughness is related to grinding vibration mode and the material removal mechanism. Surface quality of WTDUVG is superior to that of conventional grinding, and it is easy for two-dimensional ultrasonic vibration grinding that material removal mechanism is ductile mode grinding. 展开更多
关键词 two-dimension ultrasonic vibration grinding surface topography ductile grinding
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Trends of sea surface temperature and sea surface temperature fronts in the South China Sea during 2003–2017 被引量:4
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作者 Yi Yu Hao-Ran Zhang +1 位作者 Jiangbo Jin Yuntao Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第4期106-115,共10页
The trends of the sea surface temperature(SST) and SST fronts in the South China Sea(SCS) are analyzed during2003–2017 using high-resolution satellite data. The linear trend of the basin averaged SST is 0.31°C p... The trends of the sea surface temperature(SST) and SST fronts in the South China Sea(SCS) are analyzed during2003–2017 using high-resolution satellite data. The linear trend of the basin averaged SST is 0.31°C per decade,with the strongest warming identified in southeastern Vietnam. Although the rate of warming is comparable in summer and winter for the entire basin, the corresponding spatial patterns of the linear trend are substantially different between them. The SST trend to the west of the Luzon Strait is characterized by rapid warming in summer, exceeding approximately 0.6°C per decade, but the trend is insignificant in winter. The strongest warming trend occurs in the southeast of Vietnam in winter, with much less pronounced warming in summer. A positive trend of SST fronts is identified for the coast of China and is associated with increasing wind stress. The increasing trend of SST fronts is also found in the east of Vietnam. Large-scale circulation, such as El Ni?o, can influence the trends of the SST and SST fronts. A significant correlation is found between the SST anomaly and Ni?o3.4 index, and the ENSO signal leads by eight months. The basin averaged SST linear trends increase after the El Ni?o event(2009–2010), which is, at least, due to the rapid warming rate causing by the enhanced northeasterly wind. Peaks of positive anomalous SST and negatively anomalous SST fronts are found to co-occur with the strong El Ni?o events. 展开更多
关键词 South China SEA SEA surface TEMPERATURE SEA surface TEMPERATURE FRONTS warming trend wind stress
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Trend surface analysis of forest landscape pattern in Guandishan forest region of Shanxi,China 被引量:3
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作者 Guo Jin-ping Xiao Yang +1 位作者 Zhang Yun-xiang Xiao Du-ning 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第2期73-79,共7页
Landscape pattern is a widely used concept for the demonstration of landscape characteristic features. The integral spatial distribution trend of landscape elements is interested point in the landscape ecological rese... Landscape pattern is a widely used concept for the demonstration of landscape characteristic features. The integral spatial distribution trend of landscape elements is interested point in the landscape ecological research, especially in those of complex secondary forest regions with confusing mosaics of land cover. Trend surface analysis which used in community and population ecological researches was introduced to reveal the landscape pattern. A reasonable and reliable approach for application of trend surface analysis was provided in detail. As key steps of the approach, uniform grid point sampling method was developed. The efforts were also concentrated at an example of Guandishan forested landscape. Some basic rules of spatial distribution of landscape elements were exclaimed. These will be benefit to the further study in the area to enhance the forest sustainable management and landscape planning. 展开更多
关键词 landscape pattern trend surface model uniform grid point sampling method forest landscape spatial distribution.
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Historical Trends in Surface Air Temperature Estimated by Ensemble Empirical Mode Decomposition and Least Squares Linear Fitting 被引量:2
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作者 LIN Peng-Fei FENG Xiao-Li LIU Juan-Juan 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第1期10-16,共7页
Ensemble empirical mode decomposition(EEMD) and least squares linear fitting(LSLF) are applied to estimate the historical trends of surface air temperature(SAT) from observations and Coupled Model Intercomparison Proj... Ensemble empirical mode decomposition(EEMD) and least squares linear fitting(LSLF) are applied to estimate the historical trends of surface air temperature(SAT) from observations and Coupled Model Intercomparison Project Phase 5(CMIP5) simulations during the period 1901–2005. The magnitudes of trends estimated by the two approaches are comparable. The trend calculated by the EEMD approach is larger than that by the LSLF approach in most(23/27) of the models during 1901–2005. During the slow warming period, the EEMD trend is smaller than the LSLF trend. The rootmean-square errors(RMSEs) between the raw and reconstructed times series by the LSLF approach are larger than those by the EEMD trend component and multi-decadal variability components during 1901–2005 in most of the models and observations. During 1901–70(or 1971–2005), the RMSEs between the raw and reconstructed times series by LSLF are larger than those by the EEMD trend component. In this sense, the EEMD trend is a better choice to obtain the climate trends in observations and CMIP5 models, especially for short time periods. This is because the trend estimated by LSLF cannot capture the internal variability and the cooling in some years. The estimated global warming rates(trend) are consistently larger(smaller) than those from observations in 11 of 27 CMIP5 models during 1901–2005 in the slow and rapid warming periods. This implies these 11 models have consistent responses to greenhouse gases for any period. 展开更多
关键词 CLIMATE trend surface AIR TEMPERATURE CMIP5 LSLF E
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Two-dimensional silicon nanomaterials for optoelectronics
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作者 Xuebiao Deng Huai Chen Zhenyu Yang 《Journal of Semiconductors》 EI CAS CSCD 2023年第4期15-29,共15页
Silicon nanomaterials have been of immense interest in the last few decades due to their remarkable optoelectronic responses,elemental abundance,and higher biocompatibility.Two-dimensional silicon is one of the new al... Silicon nanomaterials have been of immense interest in the last few decades due to their remarkable optoelectronic responses,elemental abundance,and higher biocompatibility.Two-dimensional silicon is one of the new allotropes of silicon and has many compelling properties such as quantum-confined photoluminescence,high charge carrier mobilities,anisotropic electronic and magnetic response,and non-linear optical properties.This review summarizes the recent advances in the synthesis of two-dimensional silicon nanomaterials with a range of structures(silicene,silicane,and multilayered silicon),surface ligand engineering,and corresponding optoelectronic applications. 展开更多
关键词 two-dimensionality SILICON NANOMATERIALS SYNTHESIS surface engineering OPTOELECTRONICS
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A Trend towards a Stable Warm and Windless State of the Surface Weather Conditions in Northern and Northeastern China during 1961–2014 被引量:2
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作者 Bo SUN Huijun WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第6期713-726,共14页
This study investigates the trends in the mean state and the day-to-day variability (DDV) of the surface weather conditions over northern and northeastern China (NNEC) during 1961-2014 using CN05.1 observational d... This study investigates the trends in the mean state and the day-to-day variability (DDV) of the surface weather conditions over northern and northeastern China (NNEC) during 1961-2014 using CN05.1 observational data. In this study, we show that the surface temperature (wind speed) has increased (decreased) over NNEC and that the DDV of the surface temperatures and wind speeds has decreased, indicating a trend towards a stable warm and windless state of the surface weather conditions over NNEC. This finding implies a trend towards more persistent hot and windless episodes, which threaten human health and aggravate environmental problems. The trends are also examined in reanalysis data. Both the ERA-40 and the NCEP data show an increasing (decreasing) trend in the mean state of the surface temperatures (wind speeds). However, the reanalysis data show a consistent decreasing trend in the DDV of the surface weather conditions only in the spring. The underlying reason for the decreased DDV of the surface weather conditions is further analyzed, focusing on the spring season. Essentially, the decreased DDV of the surface weather conditions can be attributed to a decrease in synoptic-scale wave activity, which is caused by a decrease in the baroclinic instability. There is a contrasting change in the baroclinic instability over East Asia, showing a decreasing (increasing) trend north (south) of 40°N. This contrasting change in the baroclinic instability is primarily caused by a tropospheric cooling zone over East Asia at approximately 40°N, which influences the meridional temperature gradient over East Asia. 展开更多
关键词 day-to-day variability surface weather condition trend northern and northeastern China
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Remote sensing composite information's trend surface analysis of Nansha Islands coral islets and reefs' top 被引量:1
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作者 Liu Baoyin and Wang Yanfeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1999年第1期87-96,共10页
Based on the remote sensing information feature of Nansha coral islets and reefs that controlled by the Nansha Islands local area's goological structure and growth law, by means of mathematical model and PC, the N... Based on the remote sensing information feature of Nansha coral islets and reefs that controlled by the Nansha Islands local area's goological structure and growth law, by means of mathematical model and PC, the Nansha Islands coral islets and reefs' top geological data' spatial distribution and local change trend are simulated by using the trend surface system on the remote sensing composite information, and an scientific interpretation and local comparison of Nansha coral islands and islets' spatial distribution feature are made. 展开更多
关键词 Nansha Islands coral reefs remote sensing GEOMORPHOLOGY trend surface mathematical model
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Evaluation and Trend Analysis of Surface Water Quality in Zhengzhou in 1998-2008 被引量:1
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作者 Du Xile Lu Changhe 《Chinese Journal of Population,Resources and Environment》 2012年第4期44-51,共8页
Water pollution is one of the major environmental prob- lems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central ... Water pollution is one of the major environmental prob- lems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evalu- ated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen's slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCP1 ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment. 展开更多
关键词 surface water water pollution trendS NCPI Mann- Kendall test Sen's method
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Phonon Confinement Effect in Two-dimensional Nanocrystallites of Monolayer MoS_2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center 被引量:1
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作者 石薇 张昕 +4 位作者 李晓莉 乔晓粉 吴江滨 张俊 谭平恒 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期111-114,共4页
The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, whi... The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, which is well-known as the phonon confinement effect in NCs. This usually gives a downshift and asymmetric broadening of the Raman peak in various NCs. Recently, the A1 mode of 1L MoS2 NCs is found to exhibit a blue shift and asymmetric broadening toward the high-frequency side [Chem. Soc. Rev. 44 (2015) 2757 and Phys. Rev. B 91 (2015) 195411]. In this work, we carefully check this issue by studying Raman spectra of lL MoS2 NCs prepared by the ion implantation technique in a wide range of ion-implanted dosage. The same confinement coefficient is used for both E' and A'1 modes in 1L MoS2 NCs since the phonon uncertainty in an NC is mainly determined by its domain size. The asymmetrical broadening near the A'1 and E' modes is attributed to the appearance of defect-activated phonons at the zone edge and the intrinsic asymmetrical broadening of the two modes, where the anisotropy of phonon dispersion curves along Г-K and Г- M is also considered. The photoluminescence spectra confirm the formation of small domain size of 1L MoS2 nanocrystallites in the ion-implanted 1L MoS2. This study provides not only an approach to quickly probe phonon dispersion trends of 2D materials away from Г by the Raman scattering of the corresponding NCs, but also a reference to completely understand the confinement effect of different modes in various nanomaterials. 展开更多
关键词 of is NC as Phonon Confinement Effect in two-dimensional Nanocrystallites of Monolayer MoS2 to Probe Phonon Dispersion trends Away from Brillouin-Zone Center mode in from
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TREND SURFACE ANALYSIS OF THE EXISTENT SNOWLINE IN WEST CHINA
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作者 蒋忠信 《Chinese Geographical Science》 SCIE CSCD 1991年第1期64-71,共8页
The analysis of twenty five existent snowline elevation values in West China indicates that snowline elevationH (meter) presents zonality change declining from south to north with latitude φ(degree) and the change de... The analysis of twenty five existent snowline elevation values in West China indicates that snowline elevationH (meter) presents zonality change declining from south to north with latitude φ(degree) and the change declining from west to east with longitude which relates to the distance L (kilometer) to the east coastline. Therefore, the first order trend surface equation of the snowline in West China shows a plane incline from southwest to northeast. The second order trend surface equation of the snowline in West China truly represents the distribution law of the snowline in West China. Its form resembles a 'overturned anticline' from southwest to northeast. The 'raised axis' seems to be superimposed upon the first order trend surface.It reflects the effect of the relief. The snowline elevation in West China depends on horizontal zonality,distribution of ocean and land,and the relief. 展开更多
关键词 trend surface ANALYSIS SNOWLINE WEST China
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Sub-nano Layers of Li, Be, and Al on the Si(100) Surface: Electronic Structure and Silicide Formation
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作者 Victor Zavodinsky Oga Gorkusha 《Semiconductor Science and Information Devices》 2023年第1期11-17,共7页
Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(... Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(ML)thickness,were carried out.Calculations showed that band gaps of 1.02 eV,0.98 eV and 0.5 eV,respectively,appear in the densities of electronic states when the thickness of Li,Be and Al coverings is one ML.These gaps disappear with increasing thickness of the metal layers:first in the Li-Si system(for two ML),then in the Al-Si system(for three ML)and then in the Be-Si system(for four ML).This behavior of the band gap can be explained by the passivation of the substrate surface states and the peculiarities of the electronic structure of the adsorbed metals.In common the results can be interpreted as describing the possibility of the formation of a two-dimensional silicide with semiconducting properties in Li-Si(100),Be-Si(100)and Al-Si(100)systems. 展开更多
关键词 Kohn-Sham method PSEUDOPOTENTIALS Si(100)surface Sub-nano metal layers Density of states two-dimensional silicides Semiconducting properties
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Assessment of Historical Climate Trends of Surface Air Temperature in CMIP5 Models
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作者 FENG Xiao-Li ZHI Hai +1 位作者 LIN Peng-Fei LIU Hai-Long 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期137-142,共6页
This study assesses the historical climate trends of surface air temperature(SAT), their spatial distributions, and the hindcast skills for SAT during 1901– 2000 from 24 Coupled Model Intercomparison Project Phase ... This study assesses the historical climate trends of surface air temperature(SAT), their spatial distributions, and the hindcast skills for SAT during 1901– 2000 from 24 Coupled Model Intercomparison Project Phase 5(CMIP5) models. For the global averaged SAT, most of the models(17/24) effectively captured the increasing trends(0.64°C/century for the ensemble mean) as the observed values(- 0.6°C/century) during the period of 1901–2000, particularly during a rapid warming period of 1970–2000 with the small model spread. In addition, most of the models(22/24) showed high hindcast skills(the correlation coefficient, R 〉 0.8). For the spatial pattern of SAT, the models better simulated the relatively larger warming at the middle-to-high latitudes in the Northern Hemisphere than that in the Southern Hemisphere and the greater warming on the land than that in the ocean between 40°S and 40°N. The simulations underestimated the warming along some ocean boundaries but overestimated warming in the Arctic Ocean. Most of the coupled models were able to reproduce the large-scale features of SAT trends in most regions excluding Antarctica, some parts of the Pacific Ocean, the North Atlantic Ocean near Greenland, the southwestern Indian Ocean, and the Arctic Ocean. The outgoing longwave radiation(OLR) and incoming shortwave radiation(ISR) at the top of the atmosphere(TOA) and the downward longwave(LW) radiation and sensible heat flux at the surface had positive contributions to the increasing trends in most of the models. 展开更多
关键词 CMIP5 surface air temperature trend WARMING
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The Current Situation and the Development Trend of Two-dimensional Clothing in China
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作者 LI Mengmi CHEN Ying WANG Ye 《International English Education Research》 2016年第7期47-50,共4页
As a kind of subculture, The two-dimensional culture came of age during the 1970s in Japan and spread to China in the 1980s. In China, the culture has become an important economic force and social capital get more and... As a kind of subculture, The two-dimensional culture came of age during the 1970s in Japan and spread to China in the 1980s. In China, the culture has become an important economic force and social capital get more and more attention to it as well. This paper mainly discusses the origin and development of the two-dimensional clothing, and summed up the inherent characteristics and the internal developing law of it, furthermore, on the stage of current situation of two-dimensional economy this paper will conclude the development trend of next days. 展开更多
关键词 two-dimension two-dimensional clothing development trend
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Human settlement's social network analysis based on spatial trend surface model:a case study of Chongqing Municipality
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作者 ZHAO Wan-min WANG Yang GUO Jian-feng 《Ecological Economy》 2010年第4期318-323,共6页
Integrated with GIS and remote sensing(RS) technology,a systematic analysis and its methodology for human-settlements social environment has been introduced.This methodology has been called spatial trend field model(S... Integrated with GIS and remote sensing(RS) technology,a systematic analysis and its methodology for human-settlements social environment has been introduced.This methodology has been called spatial trend field model(STFM).STFM's application history in the field of human-settlements social environment has been discussed at first.Then,some index data models have been created through STFM,which include population density trend field,human activity strength trend field,city-town spatial density trend field,urbanization ratio trend field,road density trend field,GDP spatial density trend field and PER-GDP spatial density trend field.With all above-mentioned indexes as input data,through Iterative Self-Organizing Data Analysis Techniques Algorithm(ISODATA),this paper makes a verification study of Chongqing municipality.The result of the case study confirms that STFM methodology is credible and has high efficiency for regional human-settlements study. 展开更多
关键词 Human settlements environment Social network Spatial trend surface model(STSM) Geographical Information System(GIS)
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Cotton Incorporated:Color & Surface——Trend Forecast S/S 2011
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《China Textile》 2009年第12期54-56,共3页
Daredevil·Gladiator·Cherry Red·Whirlwind·Flash·Grit·Spider Grass·MercuryWith less to lose,we take a risk,creating challenges and pushingourselves in ways we only fantasized about whi... Daredevil·Gladiator·Cherry Red·Whirlwind·Flash·Grit·Spider Grass·MercuryWith less to lose,we take a risk,creating challenges and pushingourselves in ways we only fantasized about while living in the safezone.Self-tested,defying limits,we feel invigorated.Each stepwe take towards our wildest dreams brings us one step closer tothe edge.This dynamic palette merges bold and muted tones.Itschameleon nature applies from active to formal wear. 展开更多
关键词 Cotton Incorporated surface trend Forecast S/S 2011
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MODIS-Derived Arctic Land-Surface Temperature Trends
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作者 Reginald R. Muskett 《Atmospheric and Climate Sciences》 2013年第1期55-60,共6页
Across the Arctic changes in active layer, melting of glaciers and ground ice, thawing of permafrost and sequestration changes of carbon storage are driven in part by variations of land surface heat absorption, conduc... Across the Arctic changes in active layer, melting of glaciers and ground ice, thawing of permafrost and sequestration changes of carbon storage are driven in part by variations of land surface heat absorption, conduction and re-radiation relative to solar irradiance. We investigate Arctic land-surface temperature changes and regional variations derived by the MODIS sensors on NASA Aqua and Terra from March 2000 through July 2012. Over this decadal period we detect increase in the number of days with daytime land-surface temperature above 0℃. There are indications of increasing trends of land-surface temperature change. Regional variations of the changes in land-surface temperature likely arise due to surface material types and topography relative to the daytime variation of solar irradiance. 展开更多
关键词 MODIS AQUA TERRA LAND-surface Temperature trendS ARCTIC
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MODIS-Derived Nighttime Arctic Land-Surface Temperature Nascent Trends and Non-Stationary Changes
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作者 Reginald R. Muskett 《American Journal of Climate Change》 2014年第2期169-177,共9页
Arctic nighttime land-surface temperatures derived by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the NASA Terra and Aqua satellites are investigated. We use the local equator crossing ti... Arctic nighttime land-surface temperatures derived by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the NASA Terra and Aqua satellites are investigated. We use the local equator crossing times of 22:30 and 01:30, respectively, in the analysis of changes, trends and variations on the Arctic region and within 120° sectors. We show increases in the number of days above 0°C and significant increase trends over their decadal periods of March 2000 through 2010 (MODIS Terra) and July 2002 through 2012 (MODIS Aqua). The MODIS Aqua nighttime Arctic land-surface temperature change, +0.2°C ± 0.2°C with P-value of 0.01 indicates a reduction relative to the MODIS Terra nighttime Arctic land-surface temperature change, +1.8°C ± 0.3°C with P-value of 0.01. This reduction is a decadal non-stationary component of the Arctic land-surface temperature changes. The reduction is greatest, -1.3°C ± 0.2°C with P-value of 0.01 in the Eastern Russia— Western North American sector of the Arctic during the July 2002 through 2012. 展开更多
关键词 MODIS Aqua-Terra NIGHTTIME ARCTIC LAND-surface Temperature trendS NON-STATIONARY CHANGES
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Surface runoff processes and sustainable utilization of water resources in Manas River Basin, Xinjiang, China 被引量:18
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作者 HongBo LING HaiLiang XU +1 位作者 JinYi FU XinHua LIU 《Journal of Arid Land》 SCIE 2012年第3期271-280,共10页
Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and ... Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and periods of runoff based on the runoff and climate data for the past 50 years. Subsequently, with the socioeconomic and water resources data, we studied a comprehensive evaluation on the water security in this area. The results indicated that the stream flows in the three hydrological stations of Hongshanzui, Kensiwat and Bajiahu have sig- nificantly increased and undergone abrupt changes, with periods of 18 and 20 years. According to assessment, water security in the Manas River Basin was at an unsafe level in 2008. In criterion layer, the ecological security index and the index of supply-demand situation are both at the relatively secure level; the quantity index and so- cioeconomic index of water resources are at the unsafe level and basic security level, respectively. Therefore, in order to achieve sustainable economic and social development within the Manas River Basin, it is vital to take a series of effective measures to improve the status of water security. 展开更多
关键词 surface runoff processes period and trend sustainable utilization water resources the Manas River Basin fuzzycomprehensive evaluation
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Analysis on Long-Term Change of Sea Surface Temperature in the China Seas 被引量:16
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作者 LIU Qinyu ZHANG Qi 《Journal of Ocean University of China》 SCIE CAS 2013年第2期295-300,共6页
Long-term change of sea surface temperature (SST) in the China Seas from 1900 to 2006 is examined based on two different observation datasets (HadlSSTI and HadSST3). Similar to the Atlantic, SST in the China Seas ... Long-term change of sea surface temperature (SST) in the China Seas from 1900 to 2006 is examined based on two different observation datasets (HadlSSTI and HadSST3). Similar to the Atlantic, SST in the China Seas has been well observed during the past 107 years. A comparison between the reconstructed (HadISSTI) and un-interpolated (HadSST3) datasets shows that the SST wanning trends from both datasets are consistent with each other in most of the China Seas. The warming trends are stronger in winter than in summer, with a maximum rate of SST increase exceeding 2.7℃ (100year)-I in the East China Sea and the Taiwan Strait during winter based on HadISSTI. However, the SST from both datasets experienced a sudden decrease after 1999 in the China Seas. The estimated trend from HadlSSTI is stronger than that fi'om HadSST3 in the East China Sea and the east of Taiwan Island, where the difference in the linear SST warming trends are as large as about 1℃ (100year)-I when using respectively HadISST1 and HadSST3 datasets. When compared to the linear winter warnling trend of the land surface air temperature (1.6℃ (100 year)-1), HadSST3 shows a more reasonable trend of less than 2.1℃( 100 year)-1 than HadISST 1 's trend of larger than 2.7℃ ( 100 year)-1 at the mouth of the Yangtze River. The restllts also indicate large uncertainties in the estimate of SST warming patterns. 展开更多
关键词 long-term linear trend sea surface temperature China Seas reconstructed data un-interpolated data UNCERTAINTIES
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