Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo so...Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work.展开更多
2019年7月22—26日,南极研究科学委员会(SCAR)在韩国仁川举办了“第十三届南极地球科学国际会议”(the XIII International Symposium on Antarctic Earth Sciences,ISAES 2019)。SCAR的“南极地球科学国际会议”每两年举办1次,是南极...2019年7月22—26日,南极研究科学委员会(SCAR)在韩国仁川举办了“第十三届南极地球科学国际会议”(the XIII International Symposium on Antarctic Earth Sciences,ISAES 2019)。SCAR的“南极地球科学国际会议”每两年举办1次,是南极地球科学研究的重要国际学术会议。本次会议由韩国极地研究所承办,围绕南极地球科学设置了10大主题、24个分组以及12个边会。来自32个国家的超过450名南极地球科学研究学者参加了本次会议,通过将近430个不同类型的报告分享了各自的研究成果和进展。展开更多
Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the E...Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the Earth's paleo-climatic and -environmental records, and considered an ideal deep ice core drilling site. Ice thickness and subglacial topography are critical factors for ice-sheet models to determine the timescale and location of a deep ice core. During the 21st and 24th Chinese National Antarctic Research Expedition (CHINARE 21, 2004/05; CHINARE 24, 2007/08), ground-based ice radar systems were used to a three-dimensional investigation in the central 30 km×30 km region at Dome A. The successfully obtained high resolution and accuracy data of ice thickness and subglacial topography were then interpolated into the ice thickness distribution and subglacial topography digital elevation model (DEM) with a regular grid resolution of 140.5 m×140.5 m. The results of the ice radar investigation indicate that the average ice thickness in the Dome A central 30 km×30 km region is 2233 m, with a minimal ice thickness of 1618 m and a maximal ice thickness of 3139 m at Kunlun Station. The subglacial topography is relatively sharp, with an elevation range of 949-2445 m. The typical, clear mountain glaciation morphology is likely to reflect the early evolution of the Antarctic ice sheet. Based on the ice thickness distribution and subglacial topography characteristics, the location of Kunlun Station was suggested to carry out the first high-resolution, long time-scale deep ice core drilling. However, the internal structure and basal environments at Kunlun Station still need further research to determine.展开更多
Based on stake measurements conducted along the Chinese Antarctic traverse since Jan.1999,we investigated the characteristics of surface mass balance(SMB)and related climate consequences from Zhongshan Station to Dome...Based on stake measurements conducted along the Chinese Antarctic traverse since Jan.1999,we investigated the characteristics of surface mass balance(SMB)and related climate consequences from Zhongshan Station to Dome A,East Antarctica.Spatial analysis suggests that post-depositional processes have a great impact on surface morphology;thus,the representativeness of a single measurement should be discussed in conjunction with local climate features.The comparison among snow accumulation,ice sheet thickness,surface elevation,and ice velocity indicates that the bedrock topography has an indirect connection with the SMB patterns through controlling the surface topography and local climate.The observation reveals that the Lambert Glacier Basin has been experiencing increasing mass input(4.5%),whereas the inland area has experienced a 6%loss,since 2005.An overall estimation of the SMB along the route is 71.3±44.3 kg m?2 a?1,but the annual and regional variation is considerable.Tendency analysis shows that there are four sections with different SMB patterns as a result of three moisture sources and surface climatic discrepancy in the Antarctic inland.This study is the first to identify four SMB patterns from the coast to the Dome area and should provide a valuable contribution to modeling and remote sensing on a continental scale.展开更多
During the 24th Chinese National Antarctic Research Expedition(CHINARE 24,2007/08),a ground-based ice radar was used to survey ice thickness and subglacial topography along the 1170 km traverse between Zhongshan and D...During the 24th Chinese National Antarctic Research Expedition(CHINARE 24,2007/08),a ground-based ice radar was used to survey ice thickness and subglacial topography along the 1170 km traverse between Zhongshan and Dome A in East Antarctic ice sheet(EAIS).Ice-bedrock interface was detected along 82%of the traverse and data was collected at a horizontal resolution of <5.6 m.The data was processed to produce curves of ice thickness distribution and subglacial topography along the traverse.The results indicate that,along the traverse,the average ice thickness is 2037 m,smaller than the average ice thickness in EAIS;the thickest ice is at 730 km,and the thinnest ice(891 m)is at the edge of the ice sheet,but the slightly larger ice thickness(1078 m) in inland appears at 1020 km;the average subglacial topography elevation is 728 m,greatly larger than the average value in EAIS, and the largest elevation reaches up to 2650 m at 1034 km.The lowest terrain is located at 765 km.In further inland of 900?1170 km,the subglacial topography is relatively high due to the existence of the Gamburtsev Subglacial Mountains in the region.Generally,the influence of subglacial topography on ice surface is not significant,except at 900 km where great rise of subglacial topography causes evident uplift of ice surface.Where ice-bedrock interface was detected,the frequent and strong change of ice thickness and subglacial topography in small-scale means large bedrock roughness along the traverse,and is considered as the result of the integrated influence of ice flow,basal environments and geology.The segment where bedrock was not detected has very large ice thickness.The strong ice flow there also makes internal structure more complicated and induces serious attenuation of radar signals.展开更多
Dome A (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequ...Dome A (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequisite for selecting sites for deep ice core drilling that can be used for studying the paleoclimatic record. In 2004/2005, during the 21st Chinese National Antarctic Research Expedition (CHINARE 21), a 200-km long, continuous radar profile was obtained across Dome A. The internal layers along the profile were derived from the stratigraphy detected by the radar. The morphology of the isochronous layers shows that: (1) The internal layers in the shallow ice sheet (0-500 m) are generally flat, with no more than 50 m of layer intervals, and have typical synclines and anticlines in some localized regions. (2) At 500-2000 m below the surface of the ice sheet, the layers appear as 'bright layers', and the width of the layer intervals expands to 50-100 m. (3) When the basal topographic wavelengths are approximate to the thickness of the ice (3 km), the traced internal layers, with localized bumps or concave folds, are asymptotic parallel to the subglacial topography. For the longer topographic wavelengths (~20 km) wider than the thickness of the ice, the layers do not rise and fall with the basal topography. The internal layers surrounding some mountain peaks representing the most extreme variation in the terrain are sharply disturbed by the subglacial topography. (4) Layer discontinuity and fracture were detected in the basal ice sheet. Finally, by combining this new information with that derived from existing data regarding ice thickness, we were able to select three potential sites for reconstructing the age-depth relationship of the ice core.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant nos. 41776186, 41730102 and 41571407)the Chinese Polar Environmental Comprehensive Investigation and Assessment Programs (Grant no. CHINARE-02-02)
文摘Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work.
文摘2019年7月22—26日,南极研究科学委员会(SCAR)在韩国仁川举办了“第十三届南极地球科学国际会议”(the XIII International Symposium on Antarctic Earth Sciences,ISAES 2019)。SCAR的“南极地球科学国际会议”每两年举办1次,是南极地球科学研究的重要国际学术会议。本次会议由韩国极地研究所承办,围绕南极地球科学设置了10大主题、24个分组以及12个边会。来自32个国家的超过450名南极地球科学研究学者参加了本次会议,通过将近430个不同类型的报告分享了各自的研究成果和进展。
基金supported by the Ministry of Science and Technology of China (Grant No. 2006BAB18B01)National Natural Science Foundation of China (Grant No. 40476005)Polar Strategy Research Foundation in China (Grant No. 20070215)
文摘Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the Earth's paleo-climatic and -environmental records, and considered an ideal deep ice core drilling site. Ice thickness and subglacial topography are critical factors for ice-sheet models to determine the timescale and location of a deep ice core. During the 21st and 24th Chinese National Antarctic Research Expedition (CHINARE 21, 2004/05; CHINARE 24, 2007/08), ground-based ice radar systems were used to a three-dimensional investigation in the central 30 km×30 km region at Dome A. The successfully obtained high resolution and accuracy data of ice thickness and subglacial topography were then interpolated into the ice thickness distribution and subglacial topography digital elevation model (DEM) with a regular grid resolution of 140.5 m×140.5 m. The results of the ice radar investigation indicate that the average ice thickness in the Dome A central 30 km×30 km region is 2233 m, with a minimal ice thickness of 1618 m and a maximal ice thickness of 3139 m at Kunlun Station. The subglacial topography is relatively sharp, with an elevation range of 949-2445 m. The typical, clear mountain glaciation morphology is likely to reflect the early evolution of the Antarctic ice sheet. Based on the ice thickness distribution and subglacial topography characteristics, the location of Kunlun Station was suggested to carry out the first high-resolution, long time-scale deep ice core drilling. However, the internal structure and basal environments at Kunlun Station still need further research to determine.
基金supported by National Basic Research Program of China(Grant No.2013CBA01804)the National Natural Science Foundation of China(Grant Nos.41206179,41425003)+2 种基金the State Oceanic Administration of the People’s Republic of China Project on Climate in Polar Regions(Grant Nos.CHINARE2012-02-02,CHINARE2012-04-04)the State Key Laboratory of Cryospheric Sciences Opening Fund(Grant No.SKLCS 2012-01)the logistical and financial support provided by Chinese National Antarctic Research Expedition(Grant No.IC201311)
文摘Based on stake measurements conducted along the Chinese Antarctic traverse since Jan.1999,we investigated the characteristics of surface mass balance(SMB)and related climate consequences from Zhongshan Station to Dome A,East Antarctica.Spatial analysis suggests that post-depositional processes have a great impact on surface morphology;thus,the representativeness of a single measurement should be discussed in conjunction with local climate features.The comparison among snow accumulation,ice sheet thickness,surface elevation,and ice velocity indicates that the bedrock topography has an indirect connection with the SMB patterns through controlling the surface topography and local climate.The observation reveals that the Lambert Glacier Basin has been experiencing increasing mass input(4.5%),whereas the inland area has experienced a 6%loss,since 2005.An overall estimation of the SMB along the route is 71.3±44.3 kg m?2 a?1,but the annual and regional variation is considerable.Tendency analysis shows that there are four sections with different SMB patterns as a result of three moisture sources and surface climatic discrepancy in the Antarctic inland.This study is the first to identify four SMB patterns from the coast to the Dome area and should provide a valuable contribution to modeling and remote sensing on a continental scale.
基金supported by the Min-istry of Science and Technology of China(2006BAB18B01)the National Natural Science Foundation of China(40476005)the Polar Strategy Research Foundation in China(20070215)
文摘During the 24th Chinese National Antarctic Research Expedition(CHINARE 24,2007/08),a ground-based ice radar was used to survey ice thickness and subglacial topography along the 1170 km traverse between Zhongshan and Dome A in East Antarctic ice sheet(EAIS).Ice-bedrock interface was detected along 82%of the traverse and data was collected at a horizontal resolution of <5.6 m.The data was processed to produce curves of ice thickness distribution and subglacial topography along the traverse.The results indicate that,along the traverse,the average ice thickness is 2037 m,smaller than the average ice thickness in EAIS;the thickest ice is at 730 km,and the thinnest ice(891 m)is at the edge of the ice sheet,but the slightly larger ice thickness(1078 m) in inland appears at 1020 km;the average subglacial topography elevation is 728 m,greatly larger than the average value in EAIS, and the largest elevation reaches up to 2650 m at 1034 km.The lowest terrain is located at 765 km.In further inland of 900?1170 km,the subglacial topography is relatively high due to the existence of the Gamburtsev Subglacial Mountains in the region.Generally,the influence of subglacial topography on ice surface is not significant,except at 900 km where great rise of subglacial topography causes evident uplift of ice surface.Where ice-bedrock interface was detected,the frequent and strong change of ice thickness and subglacial topography in small-scale means large bedrock roughness along the traverse,and is considered as the result of the integrated influence of ice flow,basal environments and geology.The segment where bedrock was not detected has very large ice thickness.The strong ice flow there also makes internal structure more complicated and induces serious attenuation of radar signals.
基金supported by National Natural Science Foundation of China (Grant Nos. 40906101 and 40476005)National Basic Research Program of China (Grant No. 2006BAB18B01)+1 种基金IPY Chinese Programme (Grant No. IPY2008-P050400101)Polar Strategy Research Foundation in China (Grant No. 20070215)
文摘Dome A (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequisite for selecting sites for deep ice core drilling that can be used for studying the paleoclimatic record. In 2004/2005, during the 21st Chinese National Antarctic Research Expedition (CHINARE 21), a 200-km long, continuous radar profile was obtained across Dome A. The internal layers along the profile were derived from the stratigraphy detected by the radar. The morphology of the isochronous layers shows that: (1) The internal layers in the shallow ice sheet (0-500 m) are generally flat, with no more than 50 m of layer intervals, and have typical synclines and anticlines in some localized regions. (2) At 500-2000 m below the surface of the ice sheet, the layers appear as 'bright layers', and the width of the layer intervals expands to 50-100 m. (3) When the basal topographic wavelengths are approximate to the thickness of the ice (3 km), the traced internal layers, with localized bumps or concave folds, are asymptotic parallel to the subglacial topography. For the longer topographic wavelengths (~20 km) wider than the thickness of the ice, the layers do not rise and fall with the basal topography. The internal layers surrounding some mountain peaks representing the most extreme variation in the terrain are sharply disturbed by the subglacial topography. (4) Layer discontinuity and fracture were detected in the basal ice sheet. Finally, by combining this new information with that derived from existing data regarding ice thickness, we were able to select three potential sites for reconstructing the age-depth relationship of the ice core.