Recent research has shown that winter warmings are phenomenally high compared to summer warmings over the poles,especially over the Arctic.Taking the current scenario into account,this paper attempts to understand the...Recent research has shown that winter warmings are phenomenally high compared to summer warmings over the poles,especially over the Arctic.Taking the current scenario into account,this paper attempts to understand the atmospheric variables causing sea ice variability over and around the region of Svalbard for seasons;winter,spring,summer and autumn for the span of 42 years(1979-2021).The variability in atmospheric and oceanic parameters namely temperature,precipitation,wind speed,and sea surface salinity are analysed over inter-spatial,inter-seasonal and inter-annual domains.Winters are characterized by inter-annual increasing trend in temperature.During 1981-1990 the rise from the decadal mean is found to be 0.39 K·a^(-1),during 1991-2000 it is 0.20 K·a^(-1),during 2001-2010 it is 0.04 K·a^(-1) and during 2011-2020 it is 0.23 K·a^(-1).Interestingly while considering inter-spatial domains,the region southwest to Svalbard seems to be wetter(0.05 mm·(10 a)-1)compared to its northeast(-0.03 mm·(10 a)-1).Across all the three domains,wind speeds are highest during autumn and then decrease subsequently through summer,spring and are least during winter.Wind is predominantly from the south,and hence it is suspected to carry hot Atlantic air.Additionally,the significant role of salinity in the ocean also plays a key role in governing the fate of sea ice conditions.The long-term forecasts of temperature over seaice of Svalbard are alarming especially for the winter ice(r=-0.84).Correlation matrices between atmospheric and sea ice parameters are shown to gain a better understanding on their inter relation.展开更多
Pollen morphology of eight species of Saxifraga, i.e.S, cespitosa, S. oppositifolia, S. cernua, S. nivalis, S. aizoides, S. rivularis, S. hieraciifolia, and S. hirculus, collected from Ny-Alesund, Svalbard, Arctic was...Pollen morphology of eight species of Saxifraga, i.e.S, cespitosa, S. oppositifolia, S. cernua, S. nivalis, S. aizoides, S. rivularis, S. hieraciifolia, and S. hirculus, collected from Ny-Alesund, Svalbard, Arctic was examined using light and scanning electron microscopy. Pollen grains of Saxifraga species are subprolate or prolate, 3-colpate, 15.4-44.4 μm in the polar axis, 11.4 34.6 μm in the equatorial axis, and show a P/E ratio 1.19-1.40. On the basis of exine ornamentation, four pollen types, viz., the S. oppositifolia type （striate without scabrae on the muff）, S. cernua type （striate with scabrae on the muri）, S. nivalis type （microreticulate and operculum absent）, and S. cespitosa type （microechinate and operculum present）, were recognized. Hierarchical cluster analysis of the pollen morphological characters indicated that pollen morphology supports the infrageneric classification of the genus Saxifraga.展开更多
A 211 m depth ice core observation was carried out at the top of the Vestfonna Ice Cap in Nordaustlandet, Svalbard, Norway in 1995. Chronology of the ice core was determined by tritium analysis and comparison to the v...A 211 m depth ice core observation was carried out at the top of the Vestfonna Ice Cap in Nordaustlandet, Svalbard, Norway in 1995. Chronology of the ice core was determined by tritium analysis and comparison to the volcanic eruption of Laki; the resulting accumulation rate is 0.34 0.35 m water eq.·yr -1 for the last 400 year. Concentrations of Al, V, Cr, Fe, Cu, Zn, As, Ag, Cd, Pb and U in an ice core have been determined by an inductively coupled plasma mass spectrometry (ICP MS) with a desolvated micro concentric nebulizer, which is a recent development and can achieve high sensitivity with low uptake rate of 60 mL/min. The concentrations of Pb, Cu, and Zn had increased from 1940s declined from 1970s to present. However, the profiles of Pb, Cu, and Zn were different and they seem to be influenced by the difference of sources. Since the ratios between Cu, Pb, and Zn in Svalbard is similar to that in French Alps, the source area of these elements is estimated to be Europe.展开更多
Palaeo-notch sediment, accumulated in lacustrine environment, is a reliable proxy material for palaeoclimatic and palaeoenvironmental research. In this study, we collected a palaeo-notch sediment profile from the Blom...Palaeo-notch sediment, accumulated in lacustrine environment, is a reliable proxy material for palaeoclimatic and palaeoenvironmental research. In this study, we collected a palaeo-notch sediment profile from the Blomstrandhalv?ya, used multiple geochemical proxies to reconstruct palaleoproductivity variations, and investigated their link to climatic records from surrounding regions. C/N atomic ratios and carbon isotope indicate that organic matter in the sediment is mainly derived from lacustrine algae. Toward the surface sediment, the TOC, TN, P contents and the reconstructed palaeoproductivity show remarkable fluctuations with several peaks and troughs, opposite to the variation trend of the CaCO3 contents. Changes in the reconstructed palaeoproductivity are in good agreement with palaeoclimatic records from the surrounding regions, and three interruptions are likely linked to the well-known cooling periods around 1900 BP, 2800 BP and 4200 BP. Thus palaeoproductivity variations on the Blomstrandhalv?ya are mainly driven by climate changes; palaeoproductivity increase during warmer periods, and vice versa. This study will help the research of Arctic lake ecosystem and its response to climate change.展开更多
The glaciers Austre Lovenbreen and Pedersenbreen are located at Ny-（？）lesund. Svalbard.The surface mass balance and ice flow velocity of both glaciers have been determined from the first year of observations（2005/...The glaciers Austre Lovenbreen and Pedersenbreen are located at Ny-（？）lesund. Svalbard.The surface mass balance and ice flow velocity of both glaciers have been determined from the first year of observations（2005/2006）.while the front edge of Austre Lovenbreen was also surveyed.The results are as follows： （1） The net mass balances of Austre Lovenbreen and Pedersenbreen are—0.44 and—0.20 m w.e.,the annual ablation is—0.99 and—0.91 m w.e.. and the corresponding equilibrium line altitudes are 178.10 and 494.87 m.respectively. （2） Austre Lovenbreen and Pedersenbreen are characterized as ice flow models of surge-type glaciers in Svalbard.The horizontal vectors of the ice flow velocities are parallel or converge to the central lines of both glaciers,with lower velocities in the lower ablation areas and higher velocities in the middle and upper reaches of the glaciers.The vertical vectors of ice flow velocities show that there is a mass loss in the ablation areas,which reduces with increasing altitude, while there is a mass gain near the equilibrium line of Austre Lovenbreen.（3） The front edge of Austre Lovenbreen receded at an average rate of 21.83 m·a^（-1）,with remarkable variability-a maximum rate of 77.30 m·a^（-1） and a minimum rate of 2.76 m·a^（-1）.展开更多
Documenting morphological features of modem pollen is fundamental for the identification of fossil pollen, which will assist researchers to reconstruct the vegetation and climate of a particular geologic period. This ...Documenting morphological features of modem pollen is fundamental for the identification of fossil pollen, which will assist researchers to reconstruct the vegetation and climate of a particular geologic period. This paper presents the pollen morphol- ogy of 20 species of tundra plants from the high Arctic of Ny-Alesund, Svalbard, using light and scanning electron microscopy. The plants used in this study belong to 12 families： Brassicaceae, Caryophyllaceae, Cyperaceae, Ericaceae, Juncaceae, Papav- eraceae, Poaceae, Polygonaceae, Ranunculaceae, Rosaceae, Salicaceae, and Scrophulariaceae. Pollen grain shapes included： spher- oidal, subprolate, and prolate. Variable apertural patterns ranged from 2-syncolpate, 3-colpate, 3-（-4）-colpate, 3-（-5）-colpate, 3-colporate, 5-poroid, ulcerate, ulcus to pantoporate. Exine ornamentations comprised psilate, striate-perforate, reticulate, mi- croechinate, microechinate-perforate, scabrate, granulate, and granulate-perforate. This study provided a useful reference for com- parative studies of fossil pollen and for the reconstruction of paleovegetation and paleoclimate in Svalbard region of Arctic.展开更多
Discussion is focused on the characteristics of climatic change in Svalbard for the last 80 a, there the climate tend to be slightly warming. But the decreasing of temperature is an abnormal phenomenon in the backgrou...Discussion is focused on the characteristics of climatic change in Svalbard for the last 80 a, there the climate tend to be slightly warming. But the decreasing of temperature is an abnormal phenomenon in the background of global temperature increasing since the mid 1970s in Svalbard. By analysis of temperature and precipitation at key stations in the last 40 a, it is concluded that in climatic change Svalbard may be compared with the Qinghai Tibetan Plateau, though there are differences that are caused by other factors.展开更多
基于多期RTK-GPS(Real Time Kinematic-Global Position System)高精度测量数据,通过冰面高程变化开展北极Austre Lovénbreen冰川物质变化研究。首先基于冰面GPS测点开展多种空间插值方法的比对,兼顾冰面DEM(Digital Elevation Mod...基于多期RTK-GPS(Real Time Kinematic-Global Position System)高精度测量数据,通过冰面高程变化开展北极Austre Lovénbreen冰川物质变化研究。首先基于冰面GPS测点开展多种空间插值方法的比对,兼顾冰面DEM(Digital Elevation Model)的平滑特性以及插值结果的准确性,优选自然邻域法作为冰面地形的插值算法;继而利用2013—2015年3期RTK-GPS数据,通过冰面地形内插和测线交叉点比对两种方式开展了Austre Lovénbreen冰川表面高程变化的分析,结果表明交叉点方法的精度更高,而地形内插法在测线之间的空白区域存在较大误差。最后通过冰雪密度估计将高程变化转化为水当量,计算相应时段的冰川物质平衡:积累区密度取500 kg·m^-3,消融区密度取900 kg·m^-3,得到2013—2014年和2014—2015年的物质平衡分别为–0.277m w.e.和0.065m w.e.。该物质平衡结果相较于传统的冰面物质平衡而言存在一定的差异,主要源于测量时段的不一致,以及可能存在的冰川内部物质变化。此外,将RTK-GPS交叉点高程的年际变化与所在高程进行联合分析,发现冰川物质变化与冰川高程分布既有较强的相关性,部分区域也存在一些差异。总体而言,冰川物质年变化的海拔梯度为2.67‰,在海拔越低的区域冰川消融得越快,随海拔上升消融减慢,在高海拔或冰川边缘区域还存在少量物质积累。展开更多
文摘Recent research has shown that winter warmings are phenomenally high compared to summer warmings over the poles,especially over the Arctic.Taking the current scenario into account,this paper attempts to understand the atmospheric variables causing sea ice variability over and around the region of Svalbard for seasons;winter,spring,summer and autumn for the span of 42 years(1979-2021).The variability in atmospheric and oceanic parameters namely temperature,precipitation,wind speed,and sea surface salinity are analysed over inter-spatial,inter-seasonal and inter-annual domains.Winters are characterized by inter-annual increasing trend in temperature.During 1981-1990 the rise from the decadal mean is found to be 0.39 K·a^(-1),during 1991-2000 it is 0.20 K·a^(-1),during 2001-2010 it is 0.04 K·a^(-1) and during 2011-2020 it is 0.23 K·a^(-1).Interestingly while considering inter-spatial domains,the region southwest to Svalbard seems to be wetter(0.05 mm·(10 a)-1)compared to its northeast(-0.03 mm·(10 a)-1).Across all the three domains,wind speeds are highest during autumn and then decrease subsequently through summer,spring and are least during winter.Wind is predominantly from the south,and hence it is suspected to carry hot Atlantic air.Additionally,the significant role of salinity in the ocean also plays a key role in governing the fate of sea ice conditions.The long-term forecasts of temperature over seaice of Svalbard are alarming especially for the winter ice(r=-0.84).Correlation matrices between atmospheric and sea ice parameters are shown to gain a better understanding on their inter relation.
基金financially supported by the National Natural Science Foundation of China(Grant no.41271222)Main Direction Program of Knowledge Innovation of Chinese Academy of Sciences(Grant no.KSCX2-EW-J-1)+3 种基金Projects of the CAA,SOA(Grant nos.2012YR06006 and13/14YR05)SKLSEB-IBCAS(Grant no.56176G1048)Chinese Academy of Sciences Visiting Professorship for Senior International Scientists(Grant no.90004F1005)Visiting Scholarship funded by the China Scholarship Council(Grant no.201204910043)
文摘Pollen morphology of eight species of Saxifraga, i.e.S, cespitosa, S. oppositifolia, S. cernua, S. nivalis, S. aizoides, S. rivularis, S. hieraciifolia, and S. hirculus, collected from Ny-Alesund, Svalbard, Arctic was examined using light and scanning electron microscopy. Pollen grains of Saxifraga species are subprolate or prolate, 3-colpate, 15.4-44.4 μm in the polar axis, 11.4 34.6 μm in the equatorial axis, and show a P/E ratio 1.19-1.40. On the basis of exine ornamentation, four pollen types, viz., the S. oppositifolia type （striate without scabrae on the muff）, S. cernua type （striate with scabrae on the muri）, S. nivalis type （microreticulate and operculum absent）, and S. cespitosa type （microechinate and operculum present）, were recognized. Hierarchical cluster analysis of the pollen morphological characters indicated that pollen morphology supports the infrageneric classification of the genus Saxifraga.
文摘A 211 m depth ice core observation was carried out at the top of the Vestfonna Ice Cap in Nordaustlandet, Svalbard, Norway in 1995. Chronology of the ice core was determined by tritium analysis and comparison to the volcanic eruption of Laki; the resulting accumulation rate is 0.34 0.35 m water eq.·yr -1 for the last 400 year. Concentrations of Al, V, Cr, Fe, Cu, Zn, As, Ag, Cd, Pb and U in an ice core have been determined by an inductively coupled plasma mass spectrometry (ICP MS) with a desolvated micro concentric nebulizer, which is a recent development and can achieve high sensitivity with low uptake rate of 60 mL/min. The concentrations of Pb, Cu, and Zn had increased from 1940s declined from 1970s to present. However, the profiles of Pb, Cu, and Zn were different and they seem to be influenced by the difference of sources. Since the ratios between Cu, Pb, and Zn in Svalbard is similar to that in French Alps, the source area of these elements is estimated to be Europe.
基金supported by Chinese Polar Environment Comprehensive Investigation&Assessment Programs(Grant nos.CHINARE2017-02-01,CHINARE2017-04-04)
文摘Palaeo-notch sediment, accumulated in lacustrine environment, is a reliable proxy material for palaeoclimatic and palaeoenvironmental research. In this study, we collected a palaeo-notch sediment profile from the Blomstrandhalv?ya, used multiple geochemical proxies to reconstruct palaleoproductivity variations, and investigated their link to climatic records from surrounding regions. C/N atomic ratios and carbon isotope indicate that organic matter in the sediment is mainly derived from lacustrine algae. Toward the surface sediment, the TOC, TN, P contents and the reconstructed palaeoproductivity show remarkable fluctuations with several peaks and troughs, opposite to the variation trend of the CaCO3 contents. Changes in the reconstructed palaeoproductivity are in good agreement with palaeoclimatic records from the surrounding regions, and three interruptions are likely linked to the well-known cooling periods around 1900 BP, 2800 BP and 4200 BP. Thus palaeoproductivity variations on the Blomstrandhalv?ya are mainly driven by climate changes; palaeoproductivity increase during warmer periods, and vice versa. This study will help the research of Arctic lake ecosystem and its response to climate change.
文摘The glaciers Austre Lovenbreen and Pedersenbreen are located at Ny-（？）lesund. Svalbard.The surface mass balance and ice flow velocity of both glaciers have been determined from the first year of observations（2005/2006）.while the front edge of Austre Lovenbreen was also surveyed.The results are as follows： （1） The net mass balances of Austre Lovenbreen and Pedersenbreen are—0.44 and—0.20 m w.e.,the annual ablation is—0.99 and—0.91 m w.e.. and the corresponding equilibrium line altitudes are 178.10 and 494.87 m.respectively. （2） Austre Lovenbreen and Pedersenbreen are characterized as ice flow models of surge-type glaciers in Svalbard.The horizontal vectors of the ice flow velocities are parallel or converge to the central lines of both glaciers,with lower velocities in the lower ablation areas and higher velocities in the middle and upper reaches of the glaciers.The vertical vectors of ice flow velocities show that there is a mass loss in the ablation areas,which reduces with increasing altitude, while there is a mass gain near the equilibrium line of Austre Lovenbreen.（3） The front edge of Austre Lovenbreen receded at an average rate of 21.83 m·a^（-1）,with remarkable variability-a maximum rate of 77.30 m·a^（-1） and a minimum rate of 2.76 m·a^（-1）.
基金financially supported by the Main Direction Program of Knowledge Innovation of Chinese Academy of Sciences (Grant no.KSCX2-EW-J-1)State Key Laboratory Systematics and Evolutionary Botany,Institute of Botany,Chinese Academy of Sciences (SKLSEB-IBCAS,Grant no.56176G1048)
文摘Documenting morphological features of modem pollen is fundamental for the identification of fossil pollen, which will assist researchers to reconstruct the vegetation and climate of a particular geologic period. This paper presents the pollen morphol- ogy of 20 species of tundra plants from the high Arctic of Ny-Alesund, Svalbard, using light and scanning electron microscopy. The plants used in this study belong to 12 families： Brassicaceae, Caryophyllaceae, Cyperaceae, Ericaceae, Juncaceae, Papav- eraceae, Poaceae, Polygonaceae, Ranunculaceae, Rosaceae, Salicaceae, and Scrophulariaceae. Pollen grain shapes included： spher- oidal, subprolate, and prolate. Variable apertural patterns ranged from 2-syncolpate, 3-colpate, 3-（-4）-colpate, 3-（-5）-colpate, 3-colporate, 5-poroid, ulcerate, ulcus to pantoporate. Exine ornamentations comprised psilate, striate-perforate, reticulate, mi- croechinate, microechinate-perforate, scabrate, granulate, and granulate-perforate. This study provided a useful reference for com- parative studies of fossil pollen and for the reconstruction of paleovegetation and paleoclimate in Svalbard region of Arctic.
文摘Discussion is focused on the characteristics of climatic change in Svalbard for the last 80 a, there the climate tend to be slightly warming. But the decreasing of temperature is an abnormal phenomenon in the background of global temperature increasing since the mid 1970s in Svalbard. By analysis of temperature and precipitation at key stations in the last 40 a, it is concluded that in climatic change Svalbard may be compared with the Qinghai Tibetan Plateau, though there are differences that are caused by other factors.
