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Journal of Environmental Sciences 2009年第7期21卷 914-919页

作者： CONG Zhiyuan KANG Shichang qin dahe Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Cryospheric Science Chinese Academy of Sciences Lanzhou 730000 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

To assess the seasonality of aerosol deposition and anthropogenic effects on central Himalayas, a 1.85-m deep snow pit was dug on the northern slope of Mt. Qomolangma （Everest）. Based on the morphology and energy dispersive X-ray （EDX） signal, totally 1500 particles were classed into 7 groups： soot; aluminosilicates; fly ash; calcium sulfates; Ca/Mg carbonates; metal oxides; and biological particles and carbon fragments. The size distribution and number fractions of different particle groups exhibited distinct seasonal variations between non-monsoon and monsoon periods, which are clearly related to the differences in air mass pathways. Specifically, the relative abundance of soot in non-monsoon period （25%） was much higher than that in monsoon period （14%）, indicating Mt. Qomolangma region received more anthropogenic influence in non-monsoon than monsoon period.

关键词： Mt. Qomolangma seasonality SEM-EDX aerosol particle

Changes in stress within grassland ecosystems in the three counties of the source regions of the Yangtze and Yellow Rivers

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Journal of Arid Land 2010年第2期2卷 116-122页

作者： Fang, YiPing qin, dahe Ding, YongJian Chinese Acad Sci Inst Mt Disaster & Environm Chengdu 610041 Peoples R China Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China

Based on a database of more than 40 years of second production process and energy flow records for Maduo,Qumalai and Yushu counties,a dynamic model of the stress within grassland ecosys-tems was established using a nonlinear regression method for this source regions of the Yangtze and Yel-low *** results show that dynamic curves of stress within grassland ecosystems in the three coun-ties were in the shape of an inverted 'U' during the period *** also revealed that the variation in actual amount of livestock inventories reflected the general trends of the stress within the grassland eco-systems in the source regions,although there were many other factors for the increase or reduction in grassland ecosystem stress.

关键词： the source regions of Yangtze and Yellow Rivers the stress within grassland ecosystems inverted 'U' model driver

Understanding human influence on climate change in China

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National Science Review 2022年第3期9卷 128-143页

作者： Ying Sun Xuebin Zhang Yihui Ding Deliang Chen dahe qin Panmao Zhai National Climate Center Laboratory for Climate Studies Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Climate Research Division Environment and Climate Change Canada Department of Earth Sciences University of Gothenburg China Meteorological Administration State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

China’s climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes in climate have exerted substantial impacts on water resources,agriculture, ecosystems and human health. Attributing past changes to causes provides a scientific foundation for national and international climate policies. Here, we review recent progress in attributing the observed climate changes over past decades in China. Anthropogenic forcings, dominated by greenhouse gas emissions, are the main drivers for observed increases in mean and extreme temperatures. Evidence of the effect of anthropogenic forcings on precipitation is emerging. Human influence has increased the probability of extreme heat events, and has likely changed the occurrence probabilities for some heavy precipitation events. The way a specific attribution question is posed and the conditions under which the question is addressed present persistent challenges for appropriately communicating attribution results to non-specialists.

关键词： human influence detection and attribution climate change climate extremes

Organic acids:Differences in ice core records between Glacier 1,Tianshan,China and the polar areas

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Chinese Science Bulletin 2001年第1期46卷 80-83页

作者： Xinqing Li dahe qin Hui Zhou Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Formate (HCOO-), acetate (CH3COO-), oxalate (C2O42-) and pyruvate ((CO)C2O42-) are detected in a 14.08-m-long ice core recovered in Glacier 1 at the Urumqi riverhead, Tianshan, China, which is a mid-latitude alpine glacier (43°06′N, 86°49′E). the mean concentrations for the four organic acids in recent four decades are (102.8±147.3), (392.3±390.8), (6.9(+14.8) and (4.2±8.3) ng/g, respectively, with the ratio for HCOO-/CH3COO- of 0.34± 0.43. They represent the major acid components, and originate mainly from anthropogenic emission in the nearby industrial cities. Compared with Greenland and Antarctica, Glacier 1 is much higher in carboxylic acids, which were not subjected to long distance transportation as well as complicated atmospheric reactions. The alpine glacier can be, therefore, useful to reconstructing human pollution scenario to the regional atmosphere.

关键词： organic acid alpine glacier ice core atmospheric pollution Greenland Antarctica Tianshan.

Key Issues on Cryospheric Changes,Trends and Their Impacts

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Advances in Climate Change Research 2010年第1期1卷 1-10页

作者： dahe qin Yongjian Ding State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou 73000 China China Meteorological Administration Beijing 100081 China

On the basis of analyzing the importance of cryospheric researches in China and current status of cryospheric sciences in the world, this paper addresses key issues and main contents of present cryospheric sciences in China. The key issues currently addressed are： i） mechanisms of different types of glaciers in response to climate change and the scale-conversion in water resources assessments; ii） modeling of water and heat exchanges between frozen soil and vegetation; iii） parameterization of physical processes in cryosphere as well as coupling with climate models. To gain full clarification of these key issues, works of the following three aspects should be highlighted, i.e., cryospheric processes and responses to climate change, influences of cryospheric changes, and adaptation strategies for cryospheric changes.

关键词： cryosphere climate change impact water resources

A 2680-year record of sea ice extent in the Ross Sea and the associated atmospheric circulation derived from the DT401 East Antarctic ice core

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Science China Earth Sciences 2015年第11期58卷 2090-2102页

作者： LI ChuanJin REN JiaWen XIAO CunDe HOU ShuGui DING MingHu qin dahe State Key Laboratory of the Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences School of Geographic and Oceanographic Sciences Nanjing University Chinese Academy of Meteorological Sciences

Long time series of Antarctic sea ice extent （SIE） are important for climate research and model forecasting. A historic ice extent in the Ross Sea in early austral winter was rebuilt through sea salt ions in the DT401 ice core in interior East Antarctica. El Nino-Southern Oscillation （ENSO） had a significant influence on the sea salt deposition in DT401 through its influence on the Ross Sea SIE and the transport of sea salt inland. Spectral analysis also supported the influence of ENSO with a significant 2-6 a periodicity band. In addition, statistically significant decadal （10 a） and pentadecadal （50-70 a） periodicities suggested the existence of a teleconnection from the Pacific decadal oscillation （PDO）, which originated from sea surface temperature anomalies in the tropical Pacific Ocean. The first eigenvector of the empirical orthogonal function analysis （EOF1） showed lower values during the Medieval Warm Period （MWP）, while higher values were found in the Little Ice Age （LIA）. A higher frequency of ENSO events were found in the cold climatic stage, The post 1800 AD period was occupied by significant fluctuations of the EOF1, and PDO may be one of the influencing factors. The EOF1 values showed moderate fluctuations from 680 BC to 1000 AD, showing that the climate was relatively stable in this period.

关键词： sea salt ions sea ice extent ENSO DT401 Eastern Antarctica

RIVER DISCHARGE CHANGES IN THE qinGHAI-TIBET PLATEAU

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Chinese Science Bulletin 2006年第5期51卷 594-600页

作者： CAO Jianting qin dahe KANG Ersi LI Yuanyuan Laboratory for Climatic Studies China Meteorological Administration Beijing 100081 China General Institute for Water Resources and Hydropower Planning and Design Ministry of Water Resources Beijing 100011 China China Meteorological Administration Beijing 100081 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences. Lanzhou 730000 China

Annual mean discharge data of the five large rivers in the exorheic region of the qing- hai-Tibet Plateau from 1956 to 2000 are analyzed for trends with the Mann-Kendall nonparametric trend test. The results reveal that though in general no in- creasing trends exist in the total river discharges, significant regional differences of river discharge ex- ist, reflecting the decreasing trends of discharge in the Yellow River and the Tongtian River (upper Changjiang River), an increasing trend in Yalong River, and inverted change in the Lancang River and Yarlung Zangbo River. Based on analyses of the seasonal discharge, it is found that climatic change had a significant effect on the seasonal variation of river discharge in the qinghai-Tibet Plateau. In spring (from March to May) the discharge increased signifi- cantly, especially in the source area of the Yellow River. Together with the analyses on data of the mean temperature in the Northern Hemisphere and climatic data within the river basins, the relationship between discharges and mean temperature of the Northern Hemisphere is explored, which indicates that there is no increase in the stream discharge in the qinghai-Tibet Plateau with global warming. It is probably the increasing evaporation, caused by rising temperature that offsets the hydrological effect of increasing precipitation.

关键词：河流流量曼-肯德尔试验水循环青藏高原全球变暖

Spatial and temporal variability of marine-origin matter along a transect from Zhongshan Station to Dome A,Eastern Antarctica

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Journal of Environmental Sciences 2016年第8期28卷 190-202页

作者： Chuanjin Li Cunde Xiao Guitao Shi Minghu Ding dahe qin Jiawen Ren The State Key Laboratory of the Cryospheric Sciences The Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 China Climate System Institute Chinese Academy of Meteorological Sciences Beijing 100081 China Polar Research Institute of China Shanghai 200136 China

The spatiotemporal distribution pattern of marine-origin matter on the Antarctica ice sheet was used to study variations in the source regions, transport mechanisms and postdepositional influences. We present data on sea salt ions, sulfur components and stable isotopes from surface and snow pit samples collected along the transect route from Zhongshan Station to Dome A during the austral summer in 2012–2013. A general decreasing trend in the accumulation, sea salt ions and sulfur components occurred with increasing distance from the coast and increasing elevation. However, different sources of the marine components, transport pathways and post-depositional influences were responsible for their different spatial distribution patterns. The marine ions in the coastal snow pit varied seasonally, with higher sea salt ion concentrations in the winter and lower concentrations in the summer; the opposite pattern was found for the sulfur compounds. The sea ice area surrounding Antarctica was the main source region for the deposited sea salt and the open sea water for the sulfur compounds. No significant trends in the marine-origin components were detected during the past 3 decades. Several periods of elevated deposition of sea salt ions were associated with lower temperatures（based on δD and δ18O） or intensified wind fields. In comparison to the sea salt ions, the sulfur concentrations exhibited the opposite distribution patterns and were associated with changes in the surrounding sea ice extent.

关键词： Marine-origin matter Transect Dome A Eastern Antarctica

Diurnal hydrological controls and non-filtration effects on minor and trace elements in stream water draining the Qiyi Glacier, Qilian Mountain

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Science China Earth Sciences 2013年第1期56卷 81-92页

作者： LI XiangYing qin dahe JING ZheFan LI YueFang WANG NingLian State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Diurnal minor and trace elements in glacial outflow water draining the Qiyi Glacier and associated hydrological controls as well as the filtration effects on water chemistry were examined. Results show that major ions, Li, St, and Ba are exported pre- dominately as mobile monovalent or divalent ions and are controlled by hydrological variations over the diurnal cycle exhibit- ing an inverse concentration with discharge, suggesting that Li, Sr, and Ba can be used as tracers in subglacial hydrological investigations. Conversely, other elements （e.g. Fe, Al, and Cr） exhibit variations that are not strongly correlated with the dis- charge reflecting the physicochemical controls. The non-filtered operation appears not to strongly influence Sr and Ba, but has an effect on some elements such as Fe, Al, V, Ti, and Co, indicating that these changed elements are transported in particulate forms and thus their concentrations are highly dependent on particulate numbers in solutions. This implies that the immediate filtration after sampling is essential in hydrochemical studies at Alpine glacial basins due to subsequent mineral dissolution.

关键词： minor and trace elements filtration stream water Qiyi Glacier Qilian Mountain

The summer monsoon evolution recorded by carbon isotope of organic matter from the Yuanbao loess section during the Last Interglaciation

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Chinese Science Bulletin 2002年第15期47卷 1289-1291页

作者： Yong He dahe qin Jiawen Ren Fengxia Li Chinese Acad Sci Cold & Arid Regions Environm & Engn Res Inst Lanzhou 730000 Peoples R China

Based on the carbon isotope record of organic matter from the Yuanbao loess section, northwestern China, five enhanced summer monsoon events were observed at this area during the Last Interglaciation. Such events were also recorded by the paleosol layers, pollen assemblage and magnetic susceptibility. It is suggested that the enhanced summer monsoon leads to the shift of vegetation type, which results in the change of δ13C value of organic matter in the paleosol layer. It appears that the δ13C of organic matter is a good indicator for the summer monsoon variation. Among these five events, the first, second and the fifth reached their maximum smoothly, but the other two had experienced a less cold stage before reaching their peaks, which suggests that the mechanisms of such events may be different.

关键词： Chinese Loess Plateau paleosol carbon isotope of or-ganic matter summer monsoon.