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Science China Earth Sciences 2005年第2期48卷 266-272页

作者： paul A. mayewski Climate Change Institute University of Maine OronoME 04469USA

The δ18O variations in an 80.36 m ice core retrieved in the accumulation zone of the East Rongbuk Glacier, Mount Qomolangma (Everest), is not consistent with changes of air temperature from both southern and northern slopes of Himalayas, as well as these of the temperature anomalies over the Northern Hemisphere. The negative relationship between the δ18O and the net accumulation records of the ice core suggests the "amount effect" of summer precipitation on the δ18O values in the region. Therefore, the δ18O records of the East Rongbuk ice core should be a proxy of Indian Summer Monsoon intensity, which shows lower δ18O values during strong monsoon phases and higher values during weak phases.

关键词： East Rongbuk ice core δ18O values air temperature Indian Summer Monsoon.

Influencing domain of peripheral sources in the urban heavy pollution process of Beijing

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Science China Earth Sciences 2005年第4期48卷 565-575页

作者： KANG Shichang paul A. mayewski Climate Change Institute University of Maine Orono ME 04469 USA

The effect of city’s peripheral pollution sources is one of the key issues urgent to be solved in the decision-making of Beijing’s environmental pollution control. This paper comprehensively analyses the surface observations, and the satellite remote sensing data of Moderate Resolution Imaging Spectroradiometer (MODIS) and Total Ozone Mapping Spectrometer (TOMS) during the Beijing City Atmospheric Pollution Experiment (BECAPEX) from January to March, 2001, presents an "upstream" wind field resultant vector method for tracing peripheral pollution sources, and finds that the features of the urban heavy pollution processes of Beijing are significantly correlated with the impact of the emission sources of southern peripheral cities, and the pollutants transferred northwards from distant upstream sources are retarded by the U-shaped "Valley" topography in Beijing’s periphery. The two factors are responsible for the formation of the S-N zonal influencing domain of pollutants from the southern peripheral areas to Beijing. The paper also comprehensively analyses the features of flow field in the heavy pollution process in the Beijing region, and compares the heavy pollution process with samples of good air-quality days from January to March, 2001. The experiment of Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) further reveals the diffusion trajectory of pollutants of the cities in Hebei and Shandong provinces and Tianjin city in the heavy pollution process of Beijing, and the simulations of the Regional Atmosphere Model System (RAMS) confirm the possible contribution of peripheral sources to the exceptionally heavy pollution process of the urban area of Beijing, thus revealing that the input of pollutants from southern peripheral cities is one of the important factors responsible for aggravating urban heavy pollution processes.

关键词： city's periphery, distant transfer, pollutants transfer, dynamic diffusion, influencing source.

Summer monsoon and dust signals recorded in the Dasuopu firn core, central Himalayas

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Chinese Science Bulletin 1999年第21期44卷 2010-2015页

作者： Cameron P.Wake paul A.mayewski Climate Change Research Center Institute for the Study of EarthOcean and Space(EOS)University of New Hampshire DurhamNH 03824USAClimate Change Research CenterInstitute for the Study of EarthOcean and Space(EOS)University of New Hampshire DurhamNH 03824USA

In September 1997, a 15-m firn core was recovered from an elevation of 7 000 m a. s.l. from the Dasuopu Glacier in the central Himalayas. The analysis of δ18O values and major ion (Ca2+ , Mg2+ , NH4+ , SO2- and NO3-) concentrations shows that average annual accumulation is 0.75 m (water equivalent) in the Dasuopu firn core. The seasonal variations of δ18O values and major ion concentrations in the core indicate that present summer monsoon and

关键词： firn core records of summer monsoon and dust signals central Himalayas.

Changes in annual accumulation retrieved from Geladaindong ice core and its relationship to atmospheric circulation over the Tibetan Plateau

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Chinese Science Bulletin 2007年第23期52卷 3261-3266页

作者： ZHANG YongJun KANG ShiChang QIN DaHe GRIGHOLM Bjorn mayewski paul A. Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China Graduate School of CAS Beijing 100049 China National Key Laboratory of Cryospheric Sciences CAS Lanzhou 730000 China Climate Change Institute University of Maine Orono ME 04469 USA

Annual accumulation records covering 1935 to 2004 were reconstructed using Geladaindong ice core in the source of Yangtze River. A significant positive correlation between annual accumulation and precipitation from nearby meteorological stations was found, suggesting ice core accumulation could be taken as a precipitation proxy in the region. In the past 70 years, precipitation in the Geladaindong region was low from 1930s to early 1960s, and the lowest value occurred in the later 1950s. Since 1960s, precipitation increased dramatically and reached the maximum around 1980s, then decreased slightly in 1990s. By using Mann-Kendall rank statistical test method, a change point for precipitation was de- termined in 1967. Analysis of the atmospheric circulation over the Tibetan Plateau suggested that, compared with the southwest wind during the low precipitation period (before 1967), it extended about 2 latitudes northward during high precipitation period (after 1967). Moreover, during the high precipita- tion, the trough over the Bal Karshi Lake was also enhanced, and both the meridional wind and vapor transporting displayed a remarkable aggrandizement.

关键词：大气循环西藏气候学物质蓄积

Tibetan Plateau Geladaindong black carbon ice core record(1843-1982):Recent increases due to higher emissions and lower snow accumulation

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Advances in Climate Change Research 2016年第3期7卷 132-138页

作者： Matthew JENKINS Susan KASPARI KANG Shi-Chang Bjorn GRIGHOLM paul A.mayewski Department of Geological Sciences Central Washington UniversityEllensburg 98926USA State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Key Laboratory of Tibetan Environment Changes and Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Climate Change Institute University of MaineOrono 04469USA

Black carbon(BC) deposited on snow and glacier surfaces can reduce albedo and lead to accelerated melt. An ice core recovered from Guoqu glacier on Mt. Geladaindong and analyzed using a Single Particle Soot Photometer(SP2) provides the ?rst long-term(1843-1982) record of BC from the central Tibetan Plateau. Post 1940 the record is characterized by an increased occurrence of years with above average BC, and the highest BC values of the record. The BC increase in recent decades is likely caused by a combination of increased emissions from regional BC sources, and a reduction in snow accumulation. Guoqu glacier has received no net ice accumulation since the 1980 s, and is a potential example of a glacier where an increase in the equilibrium line altitude is exposing buried high impurity layers. That BC concentrations in the uppermost layers of the Geladaindong ice core are not substantially higher relative to deeper in the ice core suggests that some of the BC that must have been deposited on Guoqu glacier via wet or dry deposition between 1983 and 2005 has been removed from the surface of the glacier, potentially via supraglacial or englacial meltwater.

关键词： Black carbon Ice core Tibetan Plateau Glacier melt

Recent temperature increase recorded in an ice core in the source region of Yangtze River

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Chinese Science Bulletin 2007年第6期52卷 825-831页

作者： KANG ShiChang ZHANG YongJun QIN DaHe REN JiaWen ZHANG QiangGong Bjorn GRIGHOLM paul A. mayewski Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Cryosphere and Environment Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Climate Change Institute University of Maine Orono ME 04469 USA

Interests on climate change in the source region of Yangtze River have been raised since it is a region with the greatest warming over the Tibetan Plateau (TP). A 70-year history of precipitation δ^(18)O has been recovered using an ice core record retrieved in a plat portion of the firn area in the Guoqu Glacier (33°34′37.8″N, 91°10′35.3″E, 5720 m a.s.l.), Mt. Geladaindong (the source region of Yangtze River), in November, 2005. By using a significant positive relationship between ice core δ^(18)O record and summer air temperature (July to September) from the nearby meteorological stations, a history of summer air temperature has been reconstructed for the last 70 years. Summer temperature was relatively low in 1940s and high in 1950s to the middle of 1960s. The lowest temperature occurred in the middle of 1970s. Temperature was low in 1980s and dramatically increased since 1990s, keeping the trend to the begin-ning of the 21st century. The warming rate recorded in the ice core with 0.5℃/10 a since 1970s is much higher that that in the central TP and the Northern Hemisphere (NH), and it becomes 1.1℃/10 a since 1990s which is also higher than these from the central TP and the NH, reflecting an accelerated warm-ing and a more sensitive response to global warming in the high elevation region.

关键词：长江源头地区冰芯青藏高原温度升高 δ^18O记录

Iron in the NEEM ice core relative to Asian loess records over the last glacial–interglacial cycle

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National Science Review 2021年第7期8卷 110-123页

作者： Cunde Xiao Zhiheng Du Mike J Handley paul A mayewski Junji Cao Simon Schupbach Tong Zhang Jean-Robert Petit Chuanjin Li Yeongcheol Han Yuefang Li Jiawen Ren State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Climate Change Institute School of Earth and Climate Sciences University of Maine Key Laboratory of Aerosol Science and Technology SKLLQG Institute of Earth Environment Chinese Academy of Sciences Climate and Environmental Physics Physics Institute University of Bern 6. Institute of Tibetan Plateau and Polar Meteorology Chinese Academy of Meteorological Sciences 7. Institut des Geosciences de I'Environment (IGE) University Grenoble Alpes 8. Korea Polar Research Institute

Mineral dust can indirectly affect the climate by supplying bioavailable iron(Fe) to the ocean. Here, we present the records of dissolved Fe(DFe) and total Fe(TDFe) in North Greenland Eemian Ice Drilling(NEEM) ice core over the past 110 kyr BP. The Fe records are significantly negatively correlated with the carbon-dioxide(CO2) concentrations during cold periods. The results suggest that the changes in Fe fluxes over the past 110 kyr BP in the NEEM ice core are consistent with those in Chinese loess records because the mineral-dust distribution is controlled by the East Asian deserts. Furthermore, the variations in the dust input on a global scale are most likely driven by changes in solar radiation during the last glacial–interglacial cycle in response to Earth’s orbital cycles. In the last glacial–interglacial cycle, the DFe/TDFe ratios were higher during the warm periods(following the post-Industrial Revolution and during the Holocene and last interglacial period) than during the main cold period(i.e. the last glacial maximum(LGM)), indicating that the aeolian input of iron and the iron fertilization effect on the oceans have a non-linear relationship during different periods. Although the burning of biomass aerosols has released large amounts of DFe since the Industrial Revolution, no significant responses are observed in the DFe and TDFe variations during this period, indicating that severe anthropogenic contamination has no significant effect on the DFe(TDFe)release in the NEEM ice core.

关键词： Greenland NEEM ice core iron fertilization carbon dioxide Chinese loess glacial–interglacial cycle

A 290-a record of atmospheric circulation over the North Pacific from a Mt. Logan ice core, Yukon Territory

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Acta Oceanologica Sinica 2005年第4期24卷 81-90页

作者： KANG Shichang mayewski paul A YAN Yuping Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Climate Change Institute University of Maine Orono ME 04469 USA Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China National Climate Center Beijing 100081 China

Calibrations between sodium （Na^＋） concentrations from a Mt. Logan ice core and sea level pressure （SLP） series show that Na^＋ concentrations are closely correlated with the autumn-time （September-October-November） Aleutian low （AleuLow）. A deepening of the AleuLow strengthens the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. The Mt. Logan Na^＋ record is used to develop a 292 a （1688-1979） reconstruction of the AleuLow revealing a dramatic intensification of atmospheric circulation over the North Pacific region since the 20th century. Mean SLP of the AleuLow was about 1 hPa lower during the 20th century than during prior periods. The strongest deepening of the AleuLow appeared in the 1950s. Significant correlations are also found between the Mt. Logan AleuLow proxy series and the Pacific decadal oscillation （PDO） and Pacific circulation （PC） index during the 20th century. Evolutionary spectral analysis of the proxy record shows significant periodicities from 15 to 30 a consistent with PDO fluctuations and the bidecadal oscillation of North Pacific atmosphere-ocean circulation. A period of 11 a in the AleuLow record may be associated with the Schwabe 11-a cycle of sunspot activity. Additional longer ice core records from this region will aid in the efforts to further understand the climatic change over the North Pacific region.

关键词： atmospheric circulation ice core records North Pacific

Seasonal air temperature variations retrieved from a Geladaindong ice core, Tibetan Plateau

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Journal of Geographical Sciences 2007年第4期17卷 431-441页

作者： ZHANG Yongjun KANG Shichang QIN Dahe REN Jiawen ZHANG Yulan Bjorn GRIGHOLM paul mayewski Institute of Tibetan Plateau Research CAS Beijing 100085 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Cryosphere and Environment CAREEI CAS Lanzhou 730000 China Climate Change Institute University of Maine Orono ME 04469 USA

A 70-year history of precipitation δ^18O record has been retrieved using an ice core drilled from a plat portion of the firn area in the Guoqu Glacier （33°34＇37.8″ N, 91°10＇35.3″ E, 5720 m a.s.l.） on Mt. Geladaindong （the source region of Yangtze River） during October and November, 2005. Based on the seasonality of δ^18O records and the significant positive relationships between monsoon/non-monsoon δ^18O values and summer/spring air temperature from the nearby meteorological stations, the history of summer and spring air temperature have been reconstructed for the last 70 years. The results show that both summer and spring air temperature variations present similar trends during the last 70 years. Regression analysis indicates that the slope of the temperature-δ^18O relationship is 1.3℃/‰ for non-monsoon δ^18O values and spring air temperature, and 0.4℃/‰ for monsoon δ^18O values and summer air temperature. Variation of air temperature recorded in the ice core is consistent with that in the Northern Hemisphere （NH）, however, the warming trend in the Geladaindong region is more intense than that in the NH, reflecting a higher sensitivity to global warming in the high elevation regions. In addition, warming trend is greater in spring than in summer.

关键词： ice core δ^18O summer spring air temperature variations Mt. Geladaindong Tibetan Plateau

Spatial variations of Pb,As,and Cu in surface snow along the transect from the Zhongshan Station to Dome A,East Antarctica

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Research in Cold and Arid Regions 2018年第3期10卷 219-231页

作者： XingXing Jiang ShuGui Hou YuanSheng Li HongXi Pang Rong Hua mayewski paul Sneed Sharon ChunLei An Handley Michael Ke Liu WangBin Zhang Key Laboratory for Coast and Island Development School of Geographic and Oceanographic SciencesNanjing UniversityNanjingJiangsu 210023China Polar Research Institute of China Shanghai 200136China Climate Change Institute University of MaineOronoMaine 04469USA School of Earth and Climate Sciences University of MaineOronoMaine 04469USA

The spatial distributions of lead, arsenic, and copper （Pb, As, and Cu, respectively） in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica, are presented. The mean concentrations of Pb, As, and Cu are 1.04±1.56 pg/g, 0.39±0.08 pg/g, and 11.2±14.4 pg/g, respectively. It is estimated that anthropogenic contributions are dominant for Pb, As, and Cu. Spatially, Pb concentrations show an exponentially decreasing trend from the coast inland, while a moderate decreasing trend is observed for Cu concentrations in the coastal area （below 2,000 m above sea level （a.s.1.））. In the intermediate area （2,000-3,000 m a.s.1.）, the concentrations and enrichment factors of all these elements show high variability due to the complicated characteristics of climate and environment. On the inland plateau （above 3,000 m a.s.1.）, the high concentrations of As and Pb are induced by high deposition efficiency, the existence of polar stratospheric precipitation, and the different fraction deposition to East Antarctica. The extremely high concentrations with maximum values of 9.59 pg/g and 69.9 pg/g for Pb and Cu, respectively, are suggested to result mainly from local human activities at the station. Our results suggest that source, transport pathway, and deposition pattern, rather than distance from the coast or altitude, lead to the spatial distributions of Pb, As, and Cu; and it is further confirmed by spatial variations of the three metals deposited over the whole continent of Antarctica.

关键词： Antarctica surface snow trace metals spatial variations source and transportation