Zhisheng An

Xi'an Jiaotong University, Ch’ang-an, Shaanxi, China

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Publications (273)820.12 Total impact

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    ABSTRACT: Geochemistry of basin sediments from semi-arid regions is valuable to understand past hydroclimatic changes. Here, we investigate the links of sedimentary geochemistry (Rb, Sr, Ca/Zr, TOC, and %CaCO3), carbonate mineralogy and ostracod shell δ18O of Lake Qinghai, a basin proximal to major dust production centers at mid-latitudes of the Northern Hemisphere, to changes in depositional conditions and hydroclimate during the past 32 ka. Surface lacustrine sediments are characterized by low-Rb, high-Sr, low-Rb/Sr, high-%CaCO3 and high-Ca/Zr values, in contrast to the chemical compositions of eolian loess (high-Rb, low-Sr, high-Rb/Sr, low-%CaCO3, and low-Ca/Zr). A direct comparison of soluble Ca and Sr in two short cores with instrumental water discharge data suggests that lacustrine precipitates in Lake Qinghai are dominated by authigenic aragonite formed under Ca2+-limited water conditions, and that the accumulation rate of aragonite dominantly depends on solute fluxes into the lake during the rainy seasons (late May to September). Our high-resolution down-core records show that sediments during the last glacial (∼32–19.8 ka) had high-Rb, low-Sr, low-%CaCO3, and low-Ca/Zr, indicating eolian dust (loess) accumulation in a desiccated basin under dry glacial conditions, further supported by grain size and pollen results. This type of sedimentation was maintained during the last deglacial (∼19.8–11.5 ka), but interrupted by episodic lacustrine precipitates with high-Sr, high-%CaCO3, high-Ca/Zr, and low-Rb. At ∼11.5 ka, sedimentary Rb/Sr, Ca/Zr, %CaCO3 and TOC show dramatic and permanent changes, implying an abrupt shift in the atmospheric circulation at the onset of the Holocene in the Lake Qinghai region. Lacustrine precipitates have persisted throughout the Holocene with a maximum during the early to mid-Holocene (∼10.5–8.0 ka). Since ∼8.0 ka, the gradual and significant decreases in aragonite and Sr accumulations in tandem with increasing dust deposit and more positive ostracod δ18O may be linked to a weakening of Asian summer monsoons during the mid-to-late Holocene. Overall, our records appear to show a high sensitivity of sediment development and geochemistry in Lake Qinghai to the regional hydroclimate changes since the last glacial.
    Quaternary Science Reviews 08/2015; 122. DOI:10.1016/j.quascirev.2015.05.015 · 4.57 Impact Factor
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    ABSTRACT: The dynamics of glacialeinterglacial monsoon variability can be attributed to orbitally induced changes in summer insolation and internal boundary conditions. However, the relative impacts of astronomical and internal factors on East Asian summer monsoon variability remain controversial. Here we combine proxy data and model results to evaluate the response of East Asian summer monsoon change to these forcings. d13C of loess carbonate, a sensitive summer monsoon proxy from the western Chinese Loess Plateau, demonstrates coexistence of distinct 100-, 41- and 23-ka periods, in contrast to precession-dominated speleothem d18O records in South China. Model results indicate that insolation, ice and CO2 have distinct impacts on summer precipitation changes in East Asia, whereas their relative impacts are spatially different, with a relatively stronger insolation effect in south China and a more dominant ice/CO2 influence in north China. Combined proxy data and model results indicate that East Asian summer monsoon variability was induced by integrated effects of summer insolation and changing boundary conditions (e.g., ice sheets and CO2 concentration). Our proxy-model comparison further suggests that gradual weakening of the summer monsoon related to slowly decreasing summer insolation at astronomical timescales will be likely overwhelmed by the projected ongoing anthropogenic CO2 emissions.
    Quaternary Science Reviews 05/2015; 115:132-142. DOI:10.1016/j.quascirev.2015.03.009 · 4.57 Impact Factor
  • Journal of Geophysical Research Atmospheres 05/2015; DOI:10.1002/2014JD022880 · 3.44 Impact Factor
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    ABSTRACT: The carbon isotope composition (δ13C values) of long chain n-alkanes in lake sediments has been considered a reliable means of tracking changes in the terrigenous contribution of plants with C3 and C4 photosynthetic pathways. A key premise is that long chain leaf wax components used for isotope analysis are derived primarily from terrigenous higher plants. The role of aquatic plants in affecting δ13C values of long chain n-alkanes in lacustrine sediments may, however, have long been underestimated. In this study, we found that a large portion of long chain n-alkanes (C27 and C29) in nearshore sediments of the Lake Qinghai catchment was contributed from submerged aquatic plants, which displayed relatively positive carbon isotope composition (e.g. −26.7‰ to −15.7‰ for C29) similar to that of terrestrial C4 plants. Thus, the use of δ13C values of sedimentary C27 and C29 n-alkanes for tracing terrigenous vegetation composition may create a bias toward significant overestimate/underestimate of the proportion of terrestrial C4 plants. For sedimentary C31, however, the contribution from submerged plants was minor, so that the δ13C values for C31 n-alkane in surface sediments were in accord with those of the modern terrestrial vegetation in the Lake Qinghai region. Moreover, we found that changes in the δ13C values of sedimentary C27 and C29 n-alkanes were closely related to water depth variation. Downcore analysis further demonstrated the significant influence of endogenous lipids in lake sediments for the interpretation of terrestrial C4 vegetation and associated environment/climate reconstruction. In conclusion, our results suggest that the δ13C values of sedimentary long chain n-alkanes (C27, C29 and C31) may carry different environmental signals. While the δ13C values of C31 were a reliable proxy for C4/C3 terrestrial vegetation composition, the δ13C values of C27 and C29 n-alkanes may have recorded lake ecological conditions and sources of organic carbon, which might be affected by lake water depth.
    Organic Geochemistry 04/2015; 83-84. DOI:10.1016/j.orggeochem.2015.03.017 · 2.83 Impact Factor
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    ABSTRACT: Lake Qinghai in North China is the largest interior plateau lake in Central Asia and is climatically sensitive. An almost continuous 626-m long sediment core was drilled in an in-filled part of the southern lake basin of Lake Qinghai. The magnetic susceptibility record reveals the presence of two distinct peaks within an interval of fine-grained lacustrine sediments of Lower Pliocene age. We selected a depth interval of approximately 40 m spanning the magnetic susceptibility peaks for detailed rock magnetic and geochemical analyses in order to identify the magnetic mineralogy responsible and to assess its possible paleoenvironmental and paleomagnetic implications. Rock magnetic, X-ray diffraction analysis, scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDAX) analyses reveal that the main magnetic carrier is greigite (Fe3S4). The greigite is of early diagenetic origin and formed in an interval of high lake level and inferred relatively warm, humid climate. The greigite-enriched zones are separated by an interval of relatively high total sulfur and organic carbon content and we infer that in the adjacent greigite-bearing zones the lower concentrations of sulfur and organic carbon, and high levels of reactive iron, arrested the process of pyritization resulting in the preservation of the greigite on a timescale of several million years. The greigite zones contain narrow intervals of normally-magnetized sediments which may be previously unrecognized cryptochrons within the Gilbert Chron, or alternatively they may reflect the continued formation of greigite long after the age of deposition of the surrounding sediment matrix. This article is protected by copyright. All rights reserved.
    Geochemistry Geophysics Geosystems 04/2015; DOI:10.1002/2014GC005677 · 3.05 Impact Factor
  • Boya Sun, Weiguo Liu, Youbin Sun, Zhisheng An
    04/2015; 60(7):718-725. DOI:10.1007/s11434-014-0675-x
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    ABSTRACT: A speleothem δ(18)O record from Xiaobailong cave in southwest China characterizes changes in summer monsoon precipitation in Northeastern India, the Himalayan foothills, Bangladesh, and northern Indochina over the last 252 kyr. This record is dominated by 23-kyr precessional cycles punctuated by prominent millennial-scale oscillations that are synchronous with Heinrich events in the North Atlantic. It also shows clear glacial-interglacial variations that are consistent with marine and other terrestrial proxies but are different from the cave records in East China. Corroborated by isotope-enabled global circulation modeling, we hypothesize that this disparity reflects differing changes in atmospheric circulation and moisture trajectories associated with climate forcing as well as with associated topographic changes during glacial periods, in particular redistribution of air mass above the growing ice sheets and the exposure of the "land bridge" in the Maritime continents in the western equatorial Pacific.
    Proceedings of the National Academy of Sciences 03/2015; 112(10):201424035. DOI:10.1073/pnas.1424035112 · 9.81 Impact Factor
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    ABSTRACT: Precipitation in low latitudes is primarily controlled by the position of the intertropical convergence zone, which migrates from south to north seasonally. The Little Ice Age (defined as AD 1400–1850) was associated with low solar irradiance and high atmospheric aerosol concentrations as a result of several large volcanic eruptions. The mean position of the intertropical convergence zone over thewestern Pacific has been proposed to have shifted southwards during this interval, whichwould lead to relatively dry Little Ice Age conditions in the northern extent of the intertropical convergence zone and wet conditions around its southern limit. However, here we present a synthesis of palaeo-hydrology records from the Asian–Australian monsoon area that documents a rainfall distribution that distinctly violates the expected pattern. Our synthesis instead documents a synchronous retreat of the East Asian Summer Monsoon and the Australian Summer Monsoon into the tropics during the Little Ice Age, a pattern supported by the results of our climate model simulation of tropical precipitation over the past millennium. We suggest that this pattern over the western Pacific is best explained by a contraction in the latitudinal range over which the intertropical convergence zone seasonally migrates during the Little Ice Age. We therefore propose that rather than a strict north–south migration, the intertropical convergence zone in this region may instead expand and contract over decadal to centennial timescales in response to external forcing.
    Nature Geoscience 03/2015; 8(4):In Press. DOI:10.1038/NGEO2375 · 11.67 Impact Factor
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    ABSTRACT: Speleothem-based oxygen isotopic sequences have been widely used to reveal regional climatic changes worldwide. However, the climatic significance of speleothem δ18O variations in monsoonal China on decadal- to annual timescales remains in debate, which limits its application to paleoclimate reconstruction in the world’s largest country by population. In this study, we analyzed a seasonally resolved δ18O record of an annually layered stalagmite, XL21 whose variability covers a period of 98 years (1912–2009 AD), from Xianglong Cave, central China. The annual δ18O trend shows an inverse relationship with local monsoon precipitation, suggesting speleothem δ18O variations in this area can reflect monsoon precipitation at least on decadal timescale. Changes in moisture sources and transport pathways have little effect on the δ18O variations in speleothems/monsoon precipitation on decadal timescale, which may be ascribed to similar distances from this region to the two main moisture sources, the Bay of Bengal and West Pacific. There is an anti-phase relationship between speleothem δ18O records from central China and India during the last 98 years, which indicates the relationship between Indian monsoon intensity and speleothem δ18O from central China on short timescales requires further investigation.
    Journal of Asian Earth Sciences 03/2015; 106:150-155. DOI:10.1016/j.jseaes.2015.03.008 · 2.38 Impact Factor
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    ABSTRACT: Elemental carbon (EC) and polycyclic aromatic compounds (PACs) are potential proxies for the reconstruction of change in human activities and the origin of air masses in historic times. In this study, the historic deposition of char and soot (the two subtypes of EC) and PACs in a 150-yr sediment core from different topographic sub-basins of Lake Qinghai on the Qinghai Tibetan Plateau (QTP) were reconstructed. The objective was to explore how the variations in the concentrations of EC and PACs, the ratios of char to soot and of oxygenated-PAHs to parent-PAHs and of the composition of the PACs mixtures reflect historical changes in climate and human activity and the origin of air masses arriving at QTP. The deposition fluxes of soot in the different sub-basins were similar, averaging 0.18 (range of 0.15-0.25) and 0.16 (0.13-0.23) g m-2 yr-1, respectively, but varied for char (averaging 0.11 and 0.22 g m-2 yr-1, respectively), suggesting ubiquitous atmospheric deposition of soot and local river inputs of char. The different vertical distributions of the char/soot ratios in the different sub-basins can be interpreted by the different transport mechanisms of char and soot. An abrupt increase in soot concentrations since 1980 coincides with results from the QTP ice cores that were interpreted to be indicative of soot transport from South Asia. Similar concentration pattern of PAHs with soot and the 9,10-anthraquinone/anthracene (9,10-AQ/ANT) ratios all >2.0 suggest regional PAC sources. Increasing PAHs/soot ratios and decreasing 9,10-AQ/ANT ratios since the beginning of the 1970s indicate increasing local emissions. The historical trends of diagnostic ratios indicate an increase in fossil fuel contribution since the beginning of the 1970s. The increase of perylene concentrations with increasing core depth and the ratio of perylene to its penta-aromatic isomers indicate that perylene originates mainly from in-situ biogenic diagenesis. We demonstrate that the concentrations of EC, char, soot, and PACs in sediments can be used to reconstruct local, regional, and remote sources and transport pathways of pollutants to the QTP.
    Environmental Science and Technology 03/2015; 49(7). DOI:10.1021/es504568m · 5.48 Impact Factor
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    ABSTRACT: Variations in speleothem δ13C can reflect changes in overlying surface vegetation, which, over historical time scales, may represent the influence of human activities. Here, we examined δ13C variations in two stalagmites growing for the last 2200 years in Shennong Cave, Jiangxi Province, SE China. The two δ13C records corroborate well one another and show a prominent 6‰ enrichment of the δ13C values from AD 700 to 1100. The isotopic equilibrium for modern calcite and negative correlation between δ18O and δ13C along the growth axis suggest that the influences of kinetic fractionation are negligible. Varied correlations between Mg/Ca and Sr/Ca ratios and divergent changes between δ13C and Mg/Ca and Sr/Ca ratios from AD 700 to 1100 reveal that the prior calcite precipitation (PCP) and water–rock interaction did not dominate the increase of δ13C values. It is plausible that the obvious δ13C variation was largely influenced by the changes in vegetation cover overlying the cave. Our δ13C results, together with the records of climate and human activity from historical documentary records, suggest that: (i) prior to AD 700, small fluctuations in relatively light δ13C values reflect the presence of lush forest coverage above the cave, which was minimally disturbed by human activities; (ii) during AD 700–1100, the drastic increase in δ13C values indicates persistent and massive deforestation associated with large-scale immigration into northern Jiangxi after the Rebellion of An & Shi (AD 755–763) in the Tang Dynasty and the subsequent development of agriculture and economic activity; and (iii) since AD 1100, fluctuations in relatively high δ13C values suggest that local vegetation during the last millennium has been sparse. Since the Rebellion of An & Shi, SE China was progressively developed, coincident with deforestation and vegetation deterioration caused by human disturbance in the form of deforestation and cultivation.
    Boreas 02/2015; DOI:10.1111/bor.12112 · 2.38 Impact Factor
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    ABSTRACT: High-resolution sedimentary charcoal and black carbon (BC, including char and soot) records from a loess–soil profile, combined with magnetic susceptibility, δ13C of soil organic matter of analyses, pollen counts and other paleoenvironmental proxies reveal past fire patterns and landscape evolution over the past 12,000 years. Results from the analyses of charcoal and BC influx show that regional fire activity was high in the early and late Holocene, whereas fire was less frequent and pervasive in the middle Holocene. Locally, fires were infrequent near the study site until the Late Holocene. Soot and char analyses do not parallel changes in charcoal variability, and thus appear to reflect either a different aspect of fire activity or else these data are registering aspects of particle transportation and deposition in addition to fire characteristics.
    Quaternary Science Reviews 02/2015; 109. DOI:10.1016/j.quascirev.2014.11.013 · 4.57 Impact Factor
  • Jinzhao Liu, Weiguo Liu, Zhisheng An
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    ABSTRACT: Many studies have observed that leaf wax δDn-alkanes values differed significantly between woods and grasses in modern plants, with grasses D-depleted by 40 ‰–70 ‰. The reasons for the differences in leaf wax δDn-alkane values between woods and grasses, however, remain unclear. In this study, we measured the δD values of soil water (δDsw), leaf water (δDlw), and leaf wax n-alkane (δDn-alkane) for woods and grasses. We found no significant differences in the δD values of soil water (P = 0.82) and leaf water (P = 0.74) between the two life forms of plants. Therefore, the differences in leaf wax δDn-alkane values between woods and grasses may correlate with inherent properties of different plant life forms, such as leaf structures, biosynthetic processes, and leaf morphologies. Moreover, it is also possible that soil water with different δDsw at different depths utilized by woods and grasses may be responsible for some of the differences in leaf wax δDn-alkane values between the two life forms of plants, if woods mainly use soil water from the >100 cm depth, whereas grasses mainly use soil water from the δDn-alkane values of different plant life forms in a region.
    01/2015; 60(5). DOI:10.1007/s11434-014-0683-x
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    ABSTRACT: The North Atlantic Oscillation (NAO), although a local atmospheric mode over the North Atlantic Ocean, plays an important remote role in the Eurasian climate. However, the link between the NAO and Eurasian climate might be unstable. Here, we present a study on the relationship between the winter NAO and mid-latitude Eurasian climate, especially the mid-latitude East Asian precipitation, mainly based on meteorological data and output from an 1155-year-long coupled ocean-atmosphere model simulation. The results show that the winter NAO exerts a remarkable effect on the changes in mid-latitude Eurasian climate; however, the impact of the NAO is nonstationary. According to the model output, the impact of the NAO varies synchronously with the NAO variance with a period of around 150 years. During the high NAO variance period, the NAO has significant correlation with mid-latitude East Asian precipitation; low NAO variance periods do not. The variation of the NAO-precipitation teleconnection may arise from the changing influence of NAO on the local temperature. The NAO signal moves eastward by a zonally oriented wave train, where it modulates the atmospheric circulation structure, and thus results in the nonstationary relationship between the NAO and mid-latitude East Asian precipitation.
    Theoretical and Applied Climatology 01/2015; DOI:10.1007/s00704-015-1396-z · 1.74 Impact Factor
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    ABSTRACT: Southern Shaanxi is located on the south slope of the Qinling Mountains, and the climate here is controlled by monsoon system. The advancement and retreatment of Asian summer monsoon have an important influence on precipitation variations in this region. We collected an aragonite stalagmite XL2 from Xianglong Cave (33°00′N, 106°20′E, 940 m a.s.l) in southern Shaanxi Province, Central China. 19 subsamples, 50-100 mg, were drilled parallel to the growth planes of XL2 and dated with U-series methods at the Minnesota Isotope Laboratory. 218 powdered subsamples (~50 μg) were drilled out along the central growth axes of the stalagmite for stable isotope analyses at the Institute of Earth Environment, Chinese Academy of Sciences. Sr and Ca counts of the stalagmite were measured using the Itrax core scanner at the First Institute of Oceanography, State Oceanic Administration at 0.1 mm resolution. A total of 896 Sr/Ca data were then obtained. The results suggested that XL2 grew from 4200 to 1972 a B.P., and its growth rates varied between 0.03 and 0.18 mm/a. The average resolution of the δ18O series is about 10 a, and the average resolution of the Sr/Ca series is about 2 a. The δ18O and Sr/Ca ratios show coherent variations (r=0.20, N=218, P<0.01). For example, they both increased in ~2700a B.P., ~3500a B.P. and ~3800 a B.P., but decreased in ~2450a B.P., ~3200a B.P. and ~3900a B.P. The positive correlationship of the two series indicates that there were both controlled by monsoon precipitation variations. We thus use the proxy records of the stalagmite to reconstruct high-resolution monsoon precipitation variations in this region during the period of 1972-4200 a BP. There are three centennial scale droughts during the reconstructed period, which occurred in 2100-2200, 2700-2900 and 3400-3600 a BP. The reconstruction show significant periodicities at 127-105 yrs and 57 yrs, which may be related to solar activity and PDO/AMO, respectively. The δ18O record of XL2 is similar with the δ18O record of DAS from Dongge Cave, but the droughts in 2100-2200 and 3400-3600 a BP were not recorded in the DAS record. In contrast, there are more discrepancies between the δ18O records of XL2 and H4 in Heshang Cave. However, the three droughts were clearly recorded in H4. Considering the accurate dates and high resolutions of the three δ18O records, the discrepancies indicate regional differences of monsoon precipitation in China in the late Holocene on decadal to centennial scales.
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    ABSTRACT: The Tibetan Plateau uplift and Cenozoic global cooling are thought to induce enhanced aridification in the Asian interior. Although the onset of Asian desertification is proposed to have started in the earliest Miocene, prevailing desert environment in the Tarim Basin, currently providing much of the Asian eolian dust sources, is only a geologically recent phenomenon. Here we report episodic occurrences of lacustrine environments during the Late Miocene and investigate how the episodic lakes vanished in the basin. Our oxygen isotopic (δ(18)O) record demonstrates that before the prevailing desert environment, episodic changes frequently alternating between lacustrine and fluvial-eolian environments can be linked to orbital variations. Wetter lacustrine phases generally corresponded to periods of high eccentricity and possibly high obliquity, and vice versa, suggesting a temperature control on the regional moisture level on orbital timescales. Boron isotopic (δ(11)B) and δ(18)O records, together with other geochemical indicators, consistently show that the episodic lakes finally dried up at ∼4.9 million years ago (Ma), permanently and irreversibly. Although the episodic occurrences of lakes appear to be linked to orbitally induced global climatic changes, the plateau (Tibetan, Pamir, and Tianshan) uplift was primarily responsible for the final vanishing of the episodic lakes in the Tarim Basin, occurring at a relatively warm, stable climate period.
    Proceedings of the National Academy of Sciences 11/2014; DOI:10.1073/pnas.1410890111 · 9.81 Impact Factor
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    ABSTRACT: Extensive lacustrine deposits in the eastern Tarim Basin provide records of climate change influenced by the westerly winds and the Asian monsoon. To characterize the evolution of climate change in this region, we analyze elemental concentrations of barium (Ba) from the Ls2 drill core of Lop Nor, a paleo-lakebed located in the eastern Tarim Basin. Biogenic Ba concentrations from this drill core display a large-amplitude oscillation that generally follows a pattern similar to that of Artemisia content and ostracod assemblages, suggesting that is may serve as an index for climate change experienced in the basin. Our results indicate that biogenic Ba is especially sensitive to precipitation. All climatic proxies served in this study vary significantly over late Miocene to early Pleistocene time period. Strong aridification of eastern Tarim in the late Miocene to the early Pliocene may be attributed to a latitudinal shift in the westerly winds, which would have resulted in more moisture transported to southern and eastern Tibet. The growth of the Himalaya and Tibetan Plateau may have acted as an orographic barrier that blocked moisture sourced in the south from the northern margins of the plateau. We link weaker aridification in the late Pliocene to an increased intensity of the Indian Monsoon.
    Chinese Science Bulletin 10/2014; 59(28). DOI:10.1007/s11434-014-0327-1 · 1.37 Impact Factor
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    ABSTRACT: This article provides a comprehensive review of the global monsoon that encompasses findings from studies of both modern monsoons and paleomonsoons. We introduce a definition for the global monsoon that incorporates its three-dimensional distribution and ultimate causes, emphasizing the direct drive of seasonal pressure system changes on monsoon circulation and depicting the intensity in terms of both circulation and precipitation.We explore the global monsoon climate changes across a wide range of timescales from tectonic to intraseasonal. Common features of the global monsoon are global homogeneity, regional diversity, seasonality, quasi-periodicity, irregularity, instability, and asynchroneity. We emphasize the importance of solar insolation, Earth orbital parameters, underlying surface properties, and land-air-sea interactions for global monsoon dynamics. We discuss the primary driving force of monsoon variability on each timescale and the relationships among dynamics on multiple timescales. Natural processes and anthropogenic impacts are of great significance to the understanding of future global monsoon behavior.
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    ABSTRACT: Rapid industrialization and urbanization in developing countries has led to an increase in air pollution, along a similar trajectory to that previously experienced by the developed nations. In China, particulate pollution is a serious environmental problem that is influencing air quality, regional and global climates, and human health. In response to the extremely severe and persistent haze pollution experienced by about 800 million people during the first quarter of 2013 (refs 4, 5), the Chinese State Council announced its aim to reduce concentrations of PM2.5 (particulate matter with an aerodynamic diameter less than 2.5 micrometres) by up to 25 per cent relative to 2012 levels by 2017 (ref. 6). Such efforts however require elucidation of the factors governing the abundance and composition of PM2.5, which remain poorly constrained in China. Here we combine a comprehensive set of novel and state-of-the-art offline analytical approaches and statistical techniques to investigate the chemical nature and sources of particulate matter at urban locations in Beijing, Shanghai, Guangzhou and Xi'an during January 2013. We find that the severe haze pollution event was driven to a large extent by secondary aerosol formation, which contributed 30-77 per cent and 44-71 per cent (average for all four cities) of PM2.5 and of organic aerosol, respectively. On average, the contribution of secondary organic aerosol (SOA) and secondary inorganic aerosol (SIA) are found to be of similar importance (SOA/SIA ratios range from 0.6 to 1.4). Our results suggest that, in addition to mitigating primary particulate emissions, reducing the emissions of secondary aerosol precursors from, for example, fossil fuel combustion and biomass burning is likely to be important for controlling China's PM2.5 levels and for reducing the environmental, economic and health impacts resulting from particulate pollution.
    Nature 09/2014; 514(7521). DOI:10.1038/nature13774 · 42.35 Impact Factor

Publication Stats

10k Citations
820.12 Total Impact Points

Institutions

  • 2014–2015
    • Xi'an Jiaotong University
      Ch’ang-an, Shaanxi, China
  • 1997–2015
    • Chinese Academy of Sciences
      • • Institute of Earth Environment
      • • State Key Laboratory of Loess and Quatemary Geology
      • • Institute of Geology and Geophysics
      Peping, Beijing, China
    • Kyung Hee University
      • Pharmacy Division
      Seoul, Seoul, South Korea
  • 2006–2012
    • Fudan University
      • Department of Environmental Science and Engineering
      Shanghai, Shanghai Shi, China
    • Competence Assurance Solutions Ltd.
      XRU, England, United Kingdom
  • 2011
    • Shanghai Jiao Tong University
      • School of Environmental Science and Engineering
      Shanghai, Shanghai Shi, China
  • 2007–2009
    • Institute of Industrial Engineers
      SCE, Pennsylvania, United States
    • Beijing Normal University
      • Department of Chemistry
      Peping, Beijing, China
  • 2008
    • California College San Diego
      San Diego, California, United States
  • 2003–2005
    • Chemical Abstracts Service (A division of the American Chemical Society)
      SCE, Pennsylvania, United States
  • 2000–2002
    • Academia Sinica
      T’ai-pei, Taipei, Taiwan
  • 1999
    • Nanjing University
      • Department of Earth Science
      Nan-ching, Jiangsu Sheng, China