scholarly journals High-frequency East Asia monsoon variability during 115000 - 93000 a BP in Northern China

2021 ◽  
Vol 32 (2) ◽  
pp. 159-169
Author(s):  
Fengnian Wang ◽  
Yuejun Si ◽  
Baosheng Li ◽  
Dongfeng Niu ◽  
Xiaohao Wen ◽  
...  
Keyword(s):  
East Asia ◽  
High Frequency ◽  
Northern China ◽  
East Asia Monsoon ◽  
Monsoon Variability

scholarly journals The climate reconstruction in Shandong Peninsula, northern China, during the last millennium based on stalagmite laminae together with a comparison to <i>δ</i><sup>18</sup>O

2016 ◽  
Vol 12 (4) ◽  
pp. 871-881 ◽  
Author(s):  
Qing Wang ◽  
Houyun Zhou ◽  
Ke Cheng ◽  
Hong Chi ◽  
Chuan-Chou Shen ◽  
...  
Keyword(s):  
East Asia ◽  
Coastal Area ◽  
Northern China ◽  
Temperate Zone ◽  
Cold Climate ◽  
Shandong Peninsula ◽  
East Asia Monsoon ◽  
Monsoon Area ◽  
Warm Temperate Zone ◽  
Warm Temperate

Abstract. Stalagmite ky1, with a length of 75 mm and the upper part (from top to 42.769 mm depth) consisting of 678 laminae, was collected from Kaiyuan Cave in the coastal area of Shandong Peninsula, northern China, located in a warm temperate zone in the East Asia monsoon area. Based on high-precision dating with the U–230Th technique and continuous counting of laminae, the 1st and 678th laminae have been confirmed to be AD 1894 ± 20 and 1217 ± 20 from top to bottom, respectively. By the measurement of laminae thickness and δ18O ratios, we haved obtained the time series data of thickness of laminae and δ18O ratios from AD 1217 ± 20 to 1894 ± 20, analyzed the climatic–environmental meaning of variations in the thickness of laminae, which have a good correspondence with the cumulative departure curve of the drought–waterlog index in the historical period. The results show that, in the  ∼  678 years from AD 1217 ± 20 to 1894 ± 20, both the thickness of the laminae and the degree of fluctuation in the thickness of the laminae of stalagmite ky1 have obvious stages of variation and are completely synchronized with the contemporaneous intensity of the summer monsoons and precipitation as time changed. There is a negative correlation between the thickness of the laminae and the summer monsoon intensity and precipitation. There is a positive correlation between the degree of fluctuation in the thickness of the laminae and both the intensity of the summer monsoons and the precipitation. Therefore, for the Kaiyuan Cave in the coastal area of both the warm temperate zone and the East Asia monsoon area, the variations in the thickness of the laminae are not only related to the change in the climatic factors themselves but also related to the degree of climatic stability. In the coastal area belonging to the warm temperate zone and the East Asia monsoon area, the climate change between the LIA (Little Ice Age) and the MWP (Medieval Warm Period), in addition to less precipitation and low temperatures (a type of dry and cold climate), also shows an obviously decreasing trend in the degree of climatic stability.

scholarly journals First systematic assessment of dental growth and development in an archaic hominin (genus,Homo) from East Asia

2019 ◽  
Vol 5 (1) ◽  
pp. eaau0930 ◽  
Author(s):  
Song Xing ◽  
Paul Tafforeau ◽  
Mackie O’Hara ◽  
Mario Modesto-Mata ◽  
Laura Martín-Francés ◽  
...  
Keyword(s):  
East Asia ◽  
Growth And Development ◽  
Northern China ◽  
Modern Human ◽  
Dental Development ◽  
Systematic Assessment ◽  
Genus Homo ◽  
Human Morphology ◽  
Crown Formation ◽  
Dental Traits

Several human dental traits typical of modern humans appear to be associated with the prolonged period of development that is a key human attribute. Understanding when, and in which early hominins, these dental traits first appeared is thus of strong interest. Using x-ray multiresolution synchrotron phase-contrast microtomography, we quantify dental growth and development in an archaicHomojuvenile from the Xujiayao site in northern China dating to 161,000–224,000 years or 104,000–125,000 years before present. Despite the archaic morphology of Xujiayao hominins, most aspects of dental development of this juvenile fall within modern human ranges (e.g., prolonged crown formation time and delayed first molar eruption). For its estimated age-at-death (6.5 years), its state of dental development is comparable to that of equivalently aged modern children. These findings suggest that several facets of modern human dental growth and development evolved in East Asia before the appearance of fully modern human morphology.

Transboundary Extreme Ultrafine Dust Events in East Asia under a Warmer Monsoon Climate

2020 ◽  
Author(s):  
Gwangyong Choi
Keyword(s):  
East Asia ◽  
Large Scale ◽  
Northern China ◽  
Cold Season ◽  
Reanalysis Data ◽  
Monsoon Climate ◽  
Late 20Th Century ◽  
Spatio Temporal ◽  
Moderate Resolution Imaging Spectroradiometer ◽  
Dust Events

&lt;p&gt;Since the late 20th century East Asia has frequently experienced unprecedented transboundary extreme ultrafine dust events (TEUDEs) due to a fast economic development based on significant amount of fossil fuel consumption. In this study, spatio-temporal patterns of the TEUDEs in East Asia and the roles of synoptic climate patterns and changing large-scale atmospheric circulation systems in exacerbating the anthropogenic atmospheric pollution events causing considerable human deaths are examined. Analyses of the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua and Terra aerosol optical depth (AOD) data (2000-2019) clearly show that the pollutants are produced mainly in northern China and move toward central Korea and southern Japanese islands during cold seasons when coals consumption soars for heating. Synoptic climatic maps drawn from the NCEP-NCAR I reanalysis data for multiple TEUDEs demonstrate that a north clockwise- south anticlockwise wind vector anomaly pattern in cold seasons formed by less southward meandering of Siberian High pressure (SH) helps the stagnation of significant amount of ultrafine dusts over East Asia. It is also notable that the long-term poleward retreating trend of cold season circumpolar vortex, which is associated with less frequent gusty wind flow from the SH, may provide a favorable condition for intense, long-lasting TEUDEs across East Asia under a warmer monsoon climate.&lt;/p&gt;

scholarly journals Significant impact of the East Asia monsoon on ozone seasonal behavior in the boundary layer of Eastern China and the west Pacific region

2008 ◽  
Vol 8 (24) ◽  
pp. 7543-7555 ◽  
Author(s):  
Y. J. He ◽  
I. Uno ◽  
Z. F. Wang ◽  
P. Pochanart ◽  
J. Li ◽  
...  
Keyword(s):  
Boundary Layer ◽  
East Asia ◽  
Summer Monsoon ◽  
Eastern China ◽  
Pacific Region ◽  
The West ◽  
Seasonal Behavior ◽  
West Pacific ◽  
East Asia Monsoon ◽  
Monsoon Index

Abstract. The impact of the East Asia monsoon on the seasonal behavior of O3 in the boundary layer of Eastern China and the west Pacific region was analyzed for 2004–2006 by means of full-year nested chemical transport model simulations and continuous observational data obtained from three inland mountain sites in central and eastern China and three oceanic sites in the west Pacific region. The basic common features of O3 seasonal behaviors over all the monitoring sites are the pre- and post-monsoon peaks with a summer trough. Such bimodal seasonal patterns of O3 are predominant over the region with strong summer monsoon penetration, and become weaker or even disappear outside the monsoon region. The seasonal/geographical distribution of the pre-defined monsoon index indicated that the East Asia summer monsoon is responsible for the bimodal seasonal O3 pattern, and also partly account for the differences in the O3 seasonal variations between the inland mountain and oceanic sites. Over the inland mountain sites, the O3 concentration increased gradually from the beginning of the year, reached a maximum in June, decreased rapidly to the summer valley in July or August, and then peaked in September or October, thereafter decreased gradually again. Over the oceanic sites, O3 abundance showed a similar increasing trend beginning in January, but then decreased gradually from the end of March, followed by a wide trough with the minimum in July and August and a small peak in October or November. A sensitivity analysis performed by setting China-emission to zero revealed that the chemically produced O3 from China-emission contributed substantially to the O3 abundance, particularly the pre- and post-monsoon O3 peaks, over China mainland. We found that China-emission contributed more than 40% to total boundary layer O3 during summertime (60–70% in July) and accounted for about 40 ppb of each peak value over the inland region if without considering the effect of the nonlinear chemical productions. In contrast, over the oceanic region in the high monsoon index zone, the contribution of China-emission to total boundary layer O3 was always less than 20% (<10 ppb), and less than 10% in summer.

scholarly journals Nine-year spatial and temporal evolution of desert dust aerosols over South and East Asia as revealed by CALIOP

2018 ◽  
Vol 18 (2) ◽  
pp. 1337-1362 ◽  
Author(s):  
Emmanouil Proestakis ◽  
Vassilis Amiridis ◽  
Eleni Marinou ◽  
Aristeidis K. Georgoulias ◽  
Stavros Solomos ◽  
...  
Keyword(s):  
East Asia ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Indian Subcontinent ◽  
Northern China ◽  
Dust Aerosol ◽  
Observation Data ◽  
Transport Pathways ◽  
Desert Dust ◽  
Dust Aerosols

Abstract. We present a 3-D climatology of the desert dust distribution over South and East Asia derived using CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) data. To distinguish desert dust from total aerosol load we apply a methodology developed in the framework of EARLINET (European Aerosol Research Lidar Network). The method involves the use of the particle linear depolarization ratio and updated lidar ratio values suitable for Asian dust, applied to multiyear CALIPSO observations (January 2007–December 2015). The resulting dust product provides information on the horizontal and vertical distribution of dust aerosols over South and East Asia along with the seasonal transition of dust transport pathways. Persistent high D_AOD (dust aerosol optical depth) values at 532 nm, of the order of 0.6, are present over the arid and semi-arid desert regions. Dust aerosol transport (range, height and intensity) is subject to high seasonality, with the highest values observed during spring for northern China (Taklimakan and Gobi deserts) and during summer over the Indian subcontinent (Thar Desert). Additionally, we decompose the CALIPSO AOD (aerosol optical depth) into dust and non-dust aerosol components to reveal the non-dust AOD over the highly industrialized and densely populated regions of South and East Asia, where the non-dust aerosols yield AOD values of the order of 0.5. Furthermore, the CALIPSO-based short-term AOD and D_AOD time series and trends between January 2007 and December 2015 are calculated over South and East Asia and over selected subregions. Positive trends are observed over northwest and east China and the Indian subcontinent, whereas over southeast China trends are mostly negative. The calculated AOD trends agree well with the trends derived from Aqua MODIS (Moderate Resolution Imaging Spectroradiometer), although significant differences are observed over specific regions.

Identification and trend analysis of homogeneous rainfall zones over the East Asia monsoon region

2014 ◽  
Vol 35 (7) ◽  
pp. 1422-1433 ◽  
Author(s):  
Jehangir Ashraf Awan ◽  
Deg-Hyo Bae ◽  
Kyung-Joong Kim
Keyword(s):  
East Asia ◽  
Trend Analysis ◽  
Monsoon Region ◽  
East Asia Monsoon

scholarly journals Modeling precipitation δ<sup>18</sup>O pariability in East Asia since the Last Glacial Maximum: temperature and amount effects across different time scales

2016 ◽  
Author(s):  
Xinyu Wen ◽  
Zhengyu Liu ◽  
Zhongxiao Chen ◽  
Esther Brady ◽  
David Noone ◽  
...  
Keyword(s):  
East Asia ◽  
Temperature Effect ◽  
Southern China ◽  
Northern China ◽  
Point Of View ◽  
Central China ◽  
Maximum Temperature ◽  
Past Climate ◽  
Amount Effect ◽  
Significant Temperature

Abstract. Water isotope in precipitation has played a key role in the reconstruction of past climate on millennial and longer timescales. However, for mid-latitude regions like East Asia with complex terrain, the reliability behind the basic assumptions of the temperature effect and amount effect are based on modern observational data and still remains unclear for past climate. In the present work, we re-examine the two basic effects on seasonal, interannual, and millennial timescales in a set of time slice experiments for the period 22 ka thru 00 ka using an isotope-enable AGCM. Our study confirms the robustness of the temperature and amount effects on the seasonal cycle over China, with the temperature effect dominating in northern China, and the amount effect dominating in deep southern China, but no one distinct in the transition region of central China. However, our analysis does not show significant temperature and amount effects over China on millennial and interannual timescales, which is a challenge to those classic assumptions in past climate reconstruction. Our work helps shed light on the interpretation of the proxy record of δ18O from modeling point of view.

scholarly journals Inverse modeling of the 2021 spring super dust storms in East Asia

2022 ◽  
Author(s):  
Jianbing Jin ◽  
Mijie Pang ◽  
Arjo Segers ◽  
Wei Han ◽  
Li Fang ◽  
...  
Keyword(s):  
East Asia ◽  
Northern China ◽  
Life Cycles ◽  
Dust Storms ◽  
Dust Deposition ◽  
Concentration Data ◽  
Long Distance ◽  
The North ◽  
Modis Aod ◽  
Imperfect Knowledge

Abstract. This spring, super dust storms reappeared in East Asia after being absent for a (two) decade(s). The event caused enormous losses both in Mongolia and in China. Accurate simulation of such super sandstorms is valuable for the quantification of health damages, aviation risks, and profound impacts on the Earth system, but also to reveal the driving climate and the process of desertification. However, accurate simulation of dust life cycles is challenging mainly due to imperfect knowledge of emissions. In this study, the emissions that lead to the 2021 spring dust storms are estimated through assimilation of MODIS AOD and ground-based PM10 concentration data. To be able to use the AOD observations to represent the dust load, an Angstrom-based data screening is designed to select only observations that are dominated by dust. In addition, a non-dust AOD bias correction has been designed to remove the part of the AOD that could be attributed to other aerosols than dust. With this, the dust concentrations during the 2021 spring super storms could be reproduced and validated with concentration observations. The emission inversion results reveal that wind blown dust emissions originated from both China and Mongolia during spring 2021. Specifically, 18.3M and 27.2M ton of particles were released in Chinese desert and Mongolia desert respectively during these severe dust events. By source apportionment it has been estimated that 58 % of the dust deposited in the densely populated Fenwei Plain (FWP) in the northern China originate from transnational transport from Mongolia desert. For the North China Plain (NCP), local Chinese desert play a less significant roles in the dust affection; the long-distance transport from Mongolia contributes for about 69 % to the dust deposition in NCP, even if it locates more than 1000 km away from the nearest Mongolian desert.

Sign in / Sign up

Export Citation Format

Share Document