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The statistical characteristics of precipitation play an extremely important role in the risk assessment of drought and flood disasters and water resource management. In this paper, the precipitation concentration degree (PCD), precipitation concentration period (PCP) and precipitation concentration index (PCI) were used to analyse the spatiotemporal variation in precipitation concentration characteristics in China from 1960 to 2015. In addition, the cross-wavelet transform was used to analyse the possible dependencies and spatial characteristics between these three precipitation concentration indices (PCD, PCP and PCI) and monsoon indices (East Asian summer monsoon index, EASMI; South Asian summer monsoon index, SASMI; and South China Sea summer monsoon index, SCSSMI) of nine river basins in China. The results show that the spatial distribution of precipitation concentration indices in China has obvious north-south and east-west variability. China's precipitation concentration indices are generally declining, with weak volatility. Among these indices, the PCD (P < 0.05) and PCI (P < 0.01) have decreased significantly at rates of − 0.005/10 year and − 0.006/10 year, respectively, while there has been no obvious decrease in the PCP. Compared with the PCD before 1978, the PCD in the rainy season after 1978 has decreased. In most areas, the rainy season is concentrated in July every year; however, the rainy season has been delayed in the middle and lower reaches of the Yangtze River and has advanced mainly in the other basins. The PCI has declined since 1978, indicating a decreasing contribution of heavy precipitation to the total annual precipitation, but this change in the PCI has occurred mainly at high-value stations (PCI > 0.7), and the PCI at low-value stations has increased. Most of China's precipitation concentration indices and monsoon indices, as well as the NWRB, have small-scale (2–4 years) or medium-scale (12–15 years) oscillation periods. The oscillation periods between the precipitation concentration indices and monsoon indices in the Yangtze and Pearl River basins are more significant than those in other basins. The results of this study can help to understand the differences among the precipitation concentration characteristics in different basins in China and the intrinsic relationship between these characteristics and the summer monsoon and provide a reference for further research. [ABSTRACT FROM AUTHOR]

The wet bulb temperature (Tw) has gained considerable attention as a crucial indicator of heat-related health risks. Here we report south-to-north spatially heterogeneous trends of Tw in China over 1979-2018. We find that actual water vapor pressure (Ea) changes play a dominant role in determining the different trend of Tw in southern and northern China, which is attributed to the faster warming of high-latitude regions of East Asia as a response to climate change. This warming effect regulates large-scale atmospheric features and leads to extended impacts of the South Asia high (SAH) and the western Pacific subtropical high (WPSH) over southern China and to suppressed moisture transport. Attribution analysis using climate model simulations confirms these findings. We further find that the entire eastern China, that accommodates 94% of the country's population, is likely to experience widespread and uniform elevated thermal stress the end of this century. Our findings highlight the necessity for development of adaptation measures in eastern China to avoid adverse impacts of heat stress, suggesting similar implications for other regions as well. Attributing spatially heterogeneous heat stress trends to water vapor pressure changes driven by climate change-induced rapid warming in high-latitudes of East Asia, the authors predict widespread and uniform future heat stress in eastern China. [ABSTRACT FROM AUTHOR]

In this paper, characteristics of mathematics classrooms in the East Asian countries1 of Hong Kong and Japan are discussed based on an analysis of the data of the TIMSS 1999 Video Study. The data shows that although students in these East Asian countries did not talk a lot in the classroom, they were exposed to more instructional content. The mathematics problems they worked on were set up mainly using mathematical language, and compared with the problems solved by students in other countries, the problems took a longer duration to solve and more proof was involved. According to the judgement of an expert panel on the Hong Kong lessons (Japan did not participate in this part of the study), more advanced contents were covered and the lessons were more coherent. The mathematics presentations were more developed, and the students were more likely to be engaged in the lessons. In sum, the overall quality of the teaching in this East Asian country was judged to be high. The findings show that high quality teaching and learning can take place even in a teacher directed classroom. It is argued that these East Asian classroom practices are deeply rooted in the underlying cultural values of the classroom and the wider society. The paper ends by drawing some implications of the study for the mathematics education community in other cultures. [ABSTRACT FROM AUTHOR]

The cycle of precipitation change is key to understanding the driving mechanism of the East Asian summer monsoon (EASM). However, the dominant cycles of EASM precipitation revealed by different proxy indicators are inconsistent, leading to the "Chinese 100 kyr problem". In this study, we examine a high-resolution, approximately 350,000-year record from a low-latitude loess profile in China. Our analyses show that variations in the ratio of dithionite−citrate−bicarbonate extractable iron to total iron are dominated by the ~20-kyr cycle, reflecting changes in precipitation. In contrast, magnetic susceptibility varies with the ~100-kyr cycle and may be mainly controlled by temperature-induced redox processes or precipitation-induced signal smoothing. Our results suggest that changes in the EASM, as indicated by precipitation in this region, are mainly forced by precession-dominated insolation variations, and that precipitation and temperature may have varied with different cycles over the past ~350,000 years. Earth's orbit has tuned the variations of the East Asian summer monsoon. Here, a low latitude loess palaeoclimate record provides evidence that variation in monsoon rainfall is dominated by the precession cycle. [ABSTRACT FROM AUTHOR]

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Background: Three-North Afforestation Program (TNAP) in China is the largest ecological restoration project on Earth (ongoing from 1978 to 2050), harboring a huge area of newly planted forests, which provides a wealth of goods and ecosystem services that benefit society at levels ranging from region to East Asia. This project-induced carbon (C) sink has been expected to be large, but its size and location remain uncertain. Results: In this study, we investigated the changes in the C stocks of biomass, soil C and the C accumulation benefited from the ecological effects in the project areas from 1978 to 2017 within the Three-North regions (4.069 × 106 km2), and evaluated its project-induced C sequestration. Using a combination of remote sensing images, field observations and national forest inventory data, we estimated a total ecosystem sink of 47.06 Tg C per year (1 Tg = 1012 g) increased by the TNAP implementation. Importantly, we first found that the C sink via the ecological effects of this project could contribute to a high proportion up to 15.94%, indicating a critical role of ecological effects in shaping the distribution of C stocks in the protective forests. This finding suggests that it is necessary to explicitly consider carbon sequestration benefited from the ecological effects when estimating C sink and parameterizing C models of the restoration projects in China and globally. Conclusions: Our results update the estimates of C pools in the world's largest ecological restoration project area, demonstrating that this project has substantially contributed to mitigating the climate change. [ABSTRACT FROM AUTHOR]

Methane (CH4) is the second most potent greenhouse gas (GHG), and China emerges as the largest anthropogenic CH4 emitter by country. Current limited CH4 monitoring systems in China are unfortunately inadequate to support carbon management. Here we use the Weather Research and Forecasting model (WRF) coupled with a GHG module and satellite constrained emissions to simulate the spatiotemporal distribution of CH4 over East Asia in 2017. Model evaluations using both satellite retrievals and ground-based observations indicate reliable performance. We further inter-compare four proper orthogonal decomposition (POD)-based sensor placement algorithms and find they are able to capture main spatial features of surface CH4 under an oversampled condition. The QR pivot algorithm exhibits superiority in capturing high CH4, and it offers the best reconstruction with both high efficiency and accuracy. Areas with high CH4 concentrations and intense anthropogenic activities remain underrepresented by current CH4 sampling studies, leading to notable reconstruction error over central and eastern China. Optimal planning of 160 sensors guided by the QR pivot algorithm can yield reasonable reconstruction performance and costs of site construction. Our results can provide valuable references for future planning of CH4 monitoring sites. [ABSTRACT FROM AUTHOR]

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The annual precipitation in North China and South China shows a dipole pattern with a clear inter-decadal transition around the late 1970s. However, the relative contribution of internal variability and external forcing to this inter-decadal transition is still unclear. Here, we separate internal variability from the externally forced climate response through a set of dynamical downscaling simulations with lateral boundary conditions derived from reanalysis data and a large ensemble mean of the CMIP5 historical simulations. We find that internal variability accounts for about 65 and 55% of the inter-decadal transition of the annual precipitation in South and North China, respectively. By contrast, external forcing accounts for about 70% of the warming trend in eastern China over the second half of the 20th century. This study highlights the differential response of regional precipitation and air temperature to internal variability and external forcing over eastern China on an inter-decadal timescale. [ABSTRACT FROM AUTHOR]

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Previous palaeoenvironmental reconstructions have implied that East Asia was dominated by a zonal climate pattern during the Eocene, with an almost latitudinal arid/semiarid band at ~ 30° N. However, this long-standing model has recently been challenged by growing body of multidisciplinary evidence. Some studies indicated that central China was characterized by climatic fluctuations between humid and drier conditions during the Early Eocene, akin to the present East Asian monsoon (EAM) regime. Using palynological assemblages in the Tantou Basin, central China, we quantitatively reconstructed climate changes from the Late Palaeocene to Early Eocene to better understand climate change in central China. Palynological assemblages revealed that the coniferous and broad-leaved mixed forest in this area received no less than 800 mm of annual precipitation and experienced a climate change from warm and wet to relatively cool and dry. According to palaeoclimate curves, a sudden climate change occurred in the Early Eocene, with the mean annual temperature and precipitation decreasing by 5.1 °C and 214.8 mm, respectively, and the climate became very similar to the present climate, which is controlled by the monsoon. Therefore, this significant climate change during the Early Eocene may signal the emergence of the EAM in East Asia. [ABSTRACT FROM AUTHOR]

Driven by the outputs of four global climate models from Coupled Model Intercomparison Project Phase 5, a long-term downscaling and projection under the RCP8.5 scenario is conducted within the Coordinated Regional Downscaling Experiment East Asia phase II framework with Weather Research and Forecasting Model (WRF) and Regional Climate Model version 4 (RegCM4). All the single simulations and the ensembles well reproduce the spatial pattern of the precipitation amount over East Asia with the spatial correlations (SCORs) larger than 0.58, although bias exists in some areas. The models also reasonably present the spatial patterns of the extreme precipitation indices except the Rx5day (annual maximum consecutive 5-day precipitation) and the consecutive dry days (CDD), with the SCORs ranging between 0.43 and 0.71. In general, WRF outperforms RegCM4 in producing the spatial patterns of most extreme precipitation indices and RegCM4 generates lower root mean square errors. In the future, the precipitation amount would significantly increase in northeastern China and northwestern China and over the Tibetan Plateau, which is mainly due to the increase of precipitation intensity in WRF and frequency in RegCM4. The extreme frequency and intensity indices are projected to significantly increase over the Tibetan Plateau and some areas of northwestern China. In addition, the consecutive wet days will get significantly longer in the above regions, where the consecutive dry days will shorten, indicating more consecutive precipitation events in the future. The change in the probability distribution of the extreme indices reveals that stronger and longer-duration extreme precipitation events would get more frequent in the future. The increase of low-level specific humidity can partly explain the increase of precipitation. [ABSTRACT FROM AUTHOR]

The present study investigates a significant enhancement in the relationship between summer precipitation in Northwest China (NWC) and that in North China (NC) (the NWC and NC region) after early 2000, using the CN05.1 dataset and the NCEP-NCAR reanalysis circulation data from 1961 to 2018. The change in the relation between summer precipitation variations in these two regions after early 2000 likely relates to the change of the wave trains in mid-high latitudes. Before 2000, atmospheric circulation anomalies associated with the summer precipitation in NWC resemble the Silk Road Pattern (SRP) and the British-Baikal Corridor (BBC) pattern, but that in NC only resembles the SRP. After 2000, the summer precipitation in NWC and NC has a significant positive correlation with the BBC pattern. The BBC pattern influences summer precipitation in NWC and NC after early 2000 through the Ural blocking high, the positive 500-hPa Z anomalies over the Mediterranean Sea and Northwest Pacific, and the East Asia trough that leads the cold air to the south. These four synoptic systems co-modulate the summer precipitation in NWC and NC. In addition, when NWC has the same (opposite) sign as NC summer precipitation, there is BBC (SRP) wave train across Eurasia at high (middle) latitudes. [ABSTRACT FROM AUTHOR]

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Here we investigate the key features of early and late South China Sea summer monsoon (SCSSM) onset. To carry out the investigation, we select five extreme early and nine extreme late onset years (14 days or more, before and after the normal onset date are considered "late" and "early" onset years, respectively). Since the mean SCSSM onset occurs in May, we analyze the changes in composite mean meteorological fields during May. Next, we examine the differences in daily evolution (from 10 to 2 days before the onset) of various vital variables between the early and late SCSSM onset years. We demonstrate that during the early SCSSM onset years, surface air temperature (SAT) is warmer over the North Pacific Ocean, South China Sea (SCS), and Northern China, which gradually extend towards East Asia. These SAT anomalies over Northern China, East Asia, and SCS are due to the advection of warm anomalies from the North Pacific Ocean. Consequently, a dipole-like sea level pressure (SLP) pattern had developed, with lower SLP over East Asia, Northern China, SCS, and North Pacific Ocean, and higher SLP over the Indian Ocean. It subsequently brought moisture-laden wind from the Indian Ocean towards SCS and East Asian landmass and is responsible for early SCSSM onset. [ABSTRACT FROM AUTHOR]

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The Chinese mitten crab (Eriocheir sinensis) is a popular aquaculture product in East Asia, especially in China. In the last decade, rice–crab co-culture has rapidly expanded in China. Under this model, crabs are raised in rice fields instead of in traditional aquaculture ponds. In this study, we cultured two varieties of Chinese mitten crabs (Changjiang and Liaohe) in an alkaline region in northwest China and used Illumina MiSeq sequencing to compare the intestinal bacterial alpha diversity and community structure between traditional and co-culture aquaculture models, between two crab varieties, and between female and male crabs. Significant variations in intestinal bacterial communities were found between crab varieties and between female and male crabs but not between aquaculture models. These results show that rice–crab co-culture operations did not obviously impact the crab intestinal bacterial community compared with traditional pond aquaculture. Firmicutes was the most abundant bacterial phylum in the crab intestines (78%, relative abundance). Three dominant operational taxonomic units (OTUs) represented 73.2% of Firmicutes sequences and 56.8% of all sequences. A dominant OTU assigned as Firmicutes that was negatively correlated with crab body length, width, and weight was found in the source water for the experimental area. The results of this study suggest that the aquaculture of Chinese mitten crabs in alkaline regions requires more study to improve cultivation techniques. [ABSTRACT FROM AUTHOR]

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The land use and land cover change (LULCC) presents the large-area features since the 1980s in East Asia, particularly over China, where the largely complicated LULCC has happened for the simultaneous interconversion of croplands, forests, grasslands, and urban lands. In this study, the regional coupled model AVIM-RIEMS2.0 with dynamic vegetation process is employed to examine the impacts of LULCC on regional climate over East Asia. The results show that regional climate and terrestrial surface processes exhibit significantly seasonal and interdecadal signals in East Asia. With the influences of LULCC, forest increased 33.3% and 20.3% from the 1980s to 1990s and from the 1990s to 2000s, respectively. Meanwhile, cropland decreased 17.8% in the 1990s (compared to the 1980s) and 24.8% in the 2000s (compared to the 1990s), respectively. These transitions of land surface processes are roughly coincident with the interdecadal variations in temperature and precipitation, which trigger generally opposite changes in the 1980s as compared to the 1990s, especially over eastern China. The seasonal variability of climatic components is more evident in winter than summer, except for the precipitation. The climate change is also somewhat remarkable under the non-LULCC conditions, combined with the changes in wind fields at the 850 hPa from the simulations during three decades; they together suggest that climate change is also modulated by other controlling factors, such as East Asian monsoon circulations in addition to LULCC conversions. These results highlight the importance of LULCC in regional modeling studies, which would have practical significance in climate mitigation and adaptation over East Asia. [ABSTRACT FROM AUTHOR]

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There are various types of climate transitional zones on the earth's surface. The East Asian summer monsoon transition zone (EASMTZ) has attracted much attention due to its multiple roles. It is where most of the semi-arid regions locate in China, and semi-arid climate is unstable relative to the arid climate to its north and humid climate to its south. Therefore, EASMTZ is very sensitive to climate changes, and its land-atmosphere interaction (LA-I) is active and crucial. The LA-I is significantly affected by the complex land surface conditions and closely related to the summer monsoon climate dynamics. The LA-I and its response to summer monsoon activities is thus complicated. It includes multi-feedback mechanisms, which involve the land surface thermal-hydrological-ecological couplings, multi-interface exchanges from near surface to the free atmosphere. These feedbacks are sensitive to the summer monsoon activities. Based on a summary of the unique characteristics of EASMTZ and the main research progresses in LA-I in recent years, the issues related to LA-I are discussed in this region. Finally, the key scientific issues faced by the LA-I are proposed, and the future focuses are summarized. This work should help for the future study on the LA-I and its response to summer monsoon activities in the EASMTZ, which should contribute to the understanding of the increasing drought frequency associated with the significant warming trend in this region. [ABSTRACT FROM AUTHOR]

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Previous studies indicated that sea surface temperature (SST) anomalies in the Tropical Northern Atlantic (TNAT) have significant impacts on the August rainfall over the monsoon transitional belt (MTB) in China through inducing an atmospheric wave train over Eurasia and an anomalous anticyclone over the subtropical western North Pacific (STWNP). This study reveals that the MTB rainfall-TNAT SST linkage experiences a clear interdecadal shift around the late 1990s. The relationship was strong and significant before the late 1990s, whereas it became fairly weak after the late 1990s. Our result shows that the shift in spatial structure of Eurasian wave train induced by the TNAT SST plays an important role in the changes of the TNAT SST-MTB rainfall relationship. Before late 1990s, positive TNAT SST anomalies induces an atmospheric wave train emanating from the North Atlantic and propagating eastward to East Asia, with negative geopotential height anomalies over the MTB. In addition, a clear anticyclonic anomaly is induced over the STWNP. As such, TNAT SST anomalies have a significant impact on the MTB rainfall. After late 1990s, TNAT SST anomalies can also induce an anticyclonic anomaly over the STWNP and an atmospheric wave train over the Eurasia. However, spatial structure of the Eurasian wave train shows a significant difference. In particular, the negative geopotential height anomaly locates more northward after the late 1990s. Thus, the MTB rainfall-TNAT SST relation is weak. Further analysis also indicates that change in the MTB rainfall-TNAT SST relation is not related to change in the El Niño Southern Oscillation/North Atlantic Oscillation-TNAT SST relation. [ABSTRACT FROM AUTHOR]

The Asian monsoon (AM) played an important role in the dynastic history of China, yet it remains unknown whether AM-mediated shifts in Chinese societies affect earth surface processes to the point of exceeding natural variability. Here, we present a dust storm intensity record dating back to the first unified dynasty of China (the Qin Dynasty, 221–207 B.C.E.). Marked increases in dust storm activity coincided with unified dynasties with large populations during strong AM periods. By contrast, reduced dust storm activity corresponded to decreased population sizes and periods of civil unrest, which was co-eval with a weakened AM. The strengthened AM may have facilitated the development of Chinese civilizations, destabilizing the topsoil and thereby increasing the dust storm frequency. Beginning at least 2000 years ago, human activities might have started to overtake natural climatic variability as the dominant controls of dust storm activity in eastern China. How the Asian monsoon, earth surface processes and human development interact is not well known. Here, a new record of dust storm intensity shows a relationship between the stability of dynasties and dust storm activity for the last ~2200 years, which argues for a strong human control of dust storms in East Asia over this time. [ABSTRACT FROM AUTHOR]

We analyzed the anomalous characteristics of autumn rain in western China (ARWC) (26.2–36° N, 101.9–111.8° E) in 2017 and the related large-scale atmospheric circulations based on new monitoring indicators published by the China Meteorological Administration in 2015 and the National Center for Environmental Prediction reanalysis data. We found that the characteristics of autumn rain in the southern (33–36° N, 101.9–111.8° E) and northern (26.2–33° N, 101.9–111.8° E) regions of the monitoring area were different. The onset date of autumn rain in the north (south) of the monitoring area in 2017 was 14 (16) days earlier than in normal years, which is in the 4th (4th) place since 1961. The end of the autumn rain was 5 days later (earlier) than in normal years. The autumn rain period was 54 (63) days long, 19 (11) days longer than in normal years. The autumn rainfall in the north (south) of the monitoring area was 234.1 (322.2) mm, 72.6% (74.4%) higher than that in normal years. The amount of autumn rain in the southern region is in the second place since 1965. The cause of this significantly early onset of the ARWC in 2017 was the advanced transition of the East Asian atmospheric circulation system from a summer pattern to a winter pattern. The westerly jet in the upper troposphere appeared about 10 days earlier than in normal years. The meridional circulation of a west-high and east-low pattern was observed in the mid- and lower troposphere in the mid- and high latitudes of Eurasia. This circulation configuration resulted in an early onset of the ARWC. As a result of the influence of the persistent warming of the Indian Ocean basin-wide mode from spring to summer, the west Pacific subtropical high was extremely strong (the second strongest since 1981) and its westernmost point was greatly extended to the west (the second greatest extension since 1981) during the autumn rain period. The intensity of the moisture flux from the southwest of the western Pacific subtropical high was stronger than usual and the low trough of Lake Baikal was also strong. Cold air from the north and the abundant warm, humid water vapor from the south converged in western China, resulting in more precipitation during the autumn rain period. [ABSTRACT FROM AUTHOR]

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Based on daily precipitation records in the Sichuan province, spatiotemporal changes in extreme precipitation from 1961 to 2017 and the relation to ocean-atmospheric climate were investigated. The trends and their statistical significance were computed with the nonparametric Sen's and Mann–Kendall tests. The characteristics of mutation and period were investigated with heuristic segmentation and continuous wavelet transform. The relations between extreme precipitation and ocean-atmospheric climate were diagnosed by cross-wavelet analysis. The results comprised three aspects. (1) The intensity, frequency, and duration of extreme precipitation increased in the Sichuan plateau, while the intensity and frequency of extreme precipitation decreased, but the duration of extreme precipitation did not change in the Sichuan basin. The contrary trends of extreme precipitation indices may have been influenced by the complex local geography, dramatically increased human activity, and source transportation of water vapor. (2) Temporally, the trends in extreme precipitation indices constituted slight changes in the Sichuan province. The Sichuan province experienced notable climate change because abrupt change points were observed for most of the extreme precipitation indices. Extreme precipitation was a fluctuation process from 1961 to 2017. (3) Because there was a decrease in precipitation during the warm phase periods of El Niño events and an increase during the cool phase periods of La Niña events in the Sichuan province, we show that the El Niño-Southern Oscillation (ENSO) has longer and stronger relations with extreme precipitation than the South Asian Summer Monsoon (SASM) or East Asian Summer Monsoon (EASM). The results of the present study will facilitate better decisions concerning preparedness for extreme precipitation events and management of water hazards in the Sichuan province. [ABSTRACT FROM AUTHOR]

The relationships among heavy precipitation in the eastern region of China, the atmospheric heat source over the Tibetan Plateau and its surrounding areas, and atmospheric circulation in East Asia were investigated using the multi-variate empirical orthogonal function (MV-EOF) method and synthetic analysis on daily meteorological data from May through August 2010, which were compared with data from 2013. The MV-EOF decomposition results revealed that the atmospheric heating over the eastern region of the Tibetan Plateau and the Bay of Bengal exhibited opposite trends when heavy precipitation events occurred in South China, West China, and the middle and lower reaches of the Yangtze River. These results indicated that the land–sea thermal contrast between the eastern region of the Tibetan Plateau and the Bay of Bengal was likely one of the key factors leading to the occurrence of heavy precipitation events in the eastern region of China. The results of the synthetic analysis revealed a possible physical mechanism: When the atmospheric heating was weak over the Tibetan Plateau and strong over the Bay of Bengal, there was a strong ascending motion over the Bay of Bengal and its surrounding areas, which was conducive to maintaining the South Asian high and the western Pacific subtropical high (WPSH) in southerly positions. This also resulted in weak water vapor transport in the southwest, thus forming continuous heavy precipitation in South China. After the increase in atmospheric heating over the Tibetan Plateau, the convergence and ascending motion of the lower atmosphere were strengthened, and the South Asian high moved northward to the plateau, with a strengthened eastward extension. The WPSH then lifted northward, and the airflow around it conveyed more water vapor to West China and the middle and lower reaches of the Yangtze River, resulting in heavy precipitation in these regions. [ABSTRACT FROM AUTHOR]

This study investigates the impacts of the autumn sea surface temperature anomalies (SSTAs) on the following winter (December-January-February, DJF) 2-m air temperature anomalies (TSAs) in China and discusses the potential predictability of the DJF TSAs based on the intimate link between the DJF TSAs and autumn global SSTAs. The empirical orthogonal function (EOF) analysis suggests that the three leading EOF modes jointly account for 80% of the total TSA variances and are characterized by homogeneous spatial, north-south seesaw, and cross-structure patterns. These EOFs are temporally stable and suggest the potential predictability of the DJF TSAs. The EOF1 mode is influenced by changes in the intensities of the Siberian high, East Asian winter monsoon (EAWM), and East Asian trough related to a Eurasian teleconnection pattern, which can be tracked back to the autumn (September-October-November, SON) SSTAs. The Arctic oscillation (AO) exerts a strong influence on the EOF2 mode. The configuration of the global SON SSTAs induces the AO signal and causes a TSA oscillation between the northern and southern parts of China. The EOF3 mode is associated with the western pathway of the EAWM and the westward shift of the Siberian high, which are attributed to two SON SSTA patterns. The multiple correlation coefficients between the SSTA indices and winter atmospheric circulations suggest the cooperative contribution of the autumn global SSTAs to the DJF TSAs. Therefore, a physically motivated statistical model is established based on the autumn SSTA indices. Cross-validation suggests that this statistical forecast model shows a good performance in predicting the DJF TSAs. [ABSTRACT FROM AUTHOR]

In this study, we analyze the core assumptions and ideals of social network characteristics in East Asia and the West. By using an analytical frame derived from the literature and consisting of key antecedents of social networks, we find differences between the conventional assumptions of social network characteristics when comparing them with those found in East Asia. Moreover, we find remarkable intra-regional differences. Among these, and contrary to common beliefs about social networks, we find weak ties are neither hardly effective nor preferably used in East Asia, where strong ties are both more preferred and more powerful. Further, social ties tend to be rather consummatory and networks rather closed. Also, depending on the nature of the network, bridging either does not work or is not intended. We recommend further studies explicitly taking local context into account in order to refine or reframe extant knowledge on social networks. [ABSTRACT FROM AUTHOR]

Cattle domestication and the complex histories of East Asian cattle breeds warrant further investigation. Through analysing the genomes of 49 modern breeds and eight East Asian ancient samples, worldwide cattle are consistently classified into five continental groups based on Y-chromosome haplotypes and autosomal variants. We find that East Asian cattle populations are mainly composed of three distinct ancestries, including an earlier East Asian taurine ancestry that reached China at least -3.9 kya, a later introduced Eurasian taurine ancestry, and a novel Chinese indicine ancestry that diverged from Indian indicine approximately 36.6--49.6 kya. We also report historic introgression events that helped domestic cattle from southern China and the Tibetan Plateau achieve rapid adaptation by acquiring -2.93% and -1.22% of their genomes from banteng and yak, respectively. Our findings provide new insights into the evolutionary history of cattle and the importance of introgression in adaptation of cattle to new environmental challenges in East Asia. [ABSTRACT FROM AUTHOR]

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The variability of the East Asian winter monsoon (EAWM) can be divided into an ENSO-related part (EAW) and an ENSO-unrelated part (EAWM). The influence of EAWM on the ENSO-East Asian summer monsoon (EASM) relationship in the decaying stages of ENSO is investigated in the present study. To achieve this, ENSO is divided into four groups based on the EAWM: (1) weak EAWM-El Niño (WEAWM-EN); (2) strong EAWM-El Niño (SEAWM- EN); (3) weak EAWM-La Niña (WEAWM-LN); (4) strong EAWM-La Niña (SEAWM-LN). Composite results demonstrate that the EAWM may enhance the atmospheric responses over East Asia to ENSO for WEAWM-EN and SEAWM-LN. The corresponding low-level anticyclonic (cyclonic) anomalies over the western North Pacific (WNP) associated with El Niño (La Niña) tend to be strong. Importantly, this feature may persist into the following summer, causing abundant rainfall in northern China for WEAWM-EN cases and in southwestern China for SEAWM-LN cases. In contrast, for the SEAWM-EN and WEAWM-LN groups, the EAWMres tends to weaken the atmospheric circulation anomalies associated with El Niño or La Niña. In these cases, the anomalous WNP anticyclone or cyclone tend to be reduced and confined to lower latitudes, which results in deficient summer rainfall in northern China for SEAWM-EN and in southwestern China for WEAWM-LN. Further study suggests that anomalous EAWM may have an effect on the extra-tropical sea surface temperature anomaly, which persists into the ensuing summer and may interfere with the influences of ENSO. [ABSTRACT FROM AUTHOR]

The modern atmospheric observation and literatural historical drought-flood records were used to extract the inter-decadal signals of dry-wet modes in eastern China and reveal the possible relationship of global and China temperature changes associated with the East Asian summer monsoon advances. A climate pattern of 'wet-north and dry-south' in eastern China and cool period in China and globe are associated with the strong summer monsoon that can advance further to the northernmost part in the East Asian monsoon region. On the contrary, a climate pattern of 'dry-north and wet-south' in eastern China and a warm period in China and globe are associated with the weaker summer monsoon that only reaches the southern part in the region. An interdecadal oscillation with the timescale about 60 years was found dominating in both the dry-wet mode index series of the East Asian summer monsoon and the global temperature series after the secular climate states and long-term trend over inter-centennial timescales have been removed. [ABSTRACT FROM AUTHOR]

Dryness and wetness variations in east China were analyzed using the standardized precipitation index (SPI) based on monthly precipitation data for 1961-2005. A drying trend over North China was observed, which can be attributed to decreasing precipitation since the late 1970s. Moreover, NCAR/NCEP reanalysis dataset was used to investigate causes behind the drying trend in North China. The moisture flux on the regional boundaries of East China was calculated and a higher wavelet power spectrum for low-latitude boundaries (based on 20 and 25°N) occurred with significant periods in a 1-year band during 1961-2005; however, since 1977, a significant 1-year period can no longer be detected on the northern boundary of South China (based on 35°N). The summer moisture flux during 1961-1977, when compared to the same during 1978-2005, has increased in East China. Good matches are found between moisture alterations and precipitation changes, and are also confirmed by the periods of moisture transport along different latitudes. The significant 1-year periods of moisture transport along the mid-latitude boundary (based on 35°N) have disappeared since 1977, which could be the causes behind the drought in North China. The disappearance of the significant 1-year band of moisture transport along the mid-latitude boundary (based on 35°N) in the late 1970s could be a result of the significantly decreased moisture transport in North China in summer. When southerly winds are weakened in East Asia, the southwesterly winds can only reach the south of the lower Yangtze River, which is the major cause behind the frequent summer droughts in North China in the recent years. [ABSTRACT FROM AUTHOR]

Reconstructing the long-term series of the East Asian summer monsoon (EASM) indices may help understand long-term variability of EASM and its associations with precipitation. In this study, the summer middle-upper tropospheric temperature over the Asian-North Pacific sector is reconstructed from sea level pressure during the past 150 years, and then an atmospheric thermal contrast between Asia and the North Pacific, called the Asian-Pacific Oscillation (APO) index, is calculated from the reconstructed temperature. The results show that the APO phenomenon may occur in the reconstructed temperature fields, and its index has a significant positive/negative correlation with SST over the extratropical North Pacific/the tropical central-eastern Pacific in the past 150 years. The reconstructed summer APO index shows inter-decadal variability, with a positive phase in the 1870-1890s, the 1920s, and the 1940-1970s, indicating a stronger thermal contrast between Asia and the North Pacific, and with a negative phase in the 1860s, the 1900-1910s, and the 1980-1990s, indicating a weaker thermal contrast. Corresponding to a higher APO index in earlier decades of the twentieth century, there are more rainfall to the south of the Yangtze River and over North China and less rainfall over the Huaihe River valley. In the recent decades, however, more- and less-rain belts shifted southwards when the APO index is higher. During 1850-1900, the reconstructed APO index also showed a significant positive correlation with precipitation in some regions of North China. [ABSTRACT FROM AUTHOR]

Using observations from two remote sites during July 2004 to March 2005, we show that at Akdala (AKD, 47° 06′ N, 87° 58′ E, 562 m asl) in northern Xinjiang Province, there were high wintertime loadings of organic carbon (OC), elemental carbon (EC), and water-soluble (WS) ${\rm SO}_{4}^{2-}$, ${\rm NO}_{3}^{2-}$, and ${\rm NH}_{4}^{+}$, which is similar to the general pattern in most areas of China and East Asia. However, at Zhuzhang (ZUZ, 28° 00′ N, 99° 43′ E, 3,583 m asl) in northwestern Yunnan Province, the aerosol concentrations and compositions showed little seasonal variation except for a decreasing trend of OC from August to autumn–winter. Additionally, the OC variations dominated the seasonal variation of PM10 (particles ≤10 μm diameter) level. Chemical characteristics combined with transport information suggested sea salt origin of ionic Na + , Mg2 + , and Cl − at ZUZ. At AKD, ionic Ca2 + , Mg2 + , Na + , and Cl − primarily originated from salinized soil. Furthermore, the WS Ca2 + contributions (5.4–6%) to the PM10 mass during autumn, winter, and early spring reflected a constant dust component. The results of this study indicated that both sites were regionally representative. However, the representative regions and scales of these background sites may vary seasonally as the regional atmospheric transport patterns change. Seasonal variations in the background aerosol levels from these two areas need to be considered when evaluating the regional climate effects of the aerosols. [ABSTRACT FROM AUTHOR]

Presents the results of a study of the climatological aspect of seasonal rainfall distribution in the East Asian monsoon region, which includes China, Korea and Japan. Introduction; Dataset and method; Precipitation feature; Seasonal transition and sub-seasonal oscillation; Zonal distribution; Spatial distribution; Conclusion and discussion.

Emperor CAO Cao (155AD-220AD) is one of the most famous persons in Chinese history that had changed the history of East Asia. He claimed to be a descendant of Marquis CAO Can and therefore was of aristocratic ancestry. However, this claim has been suspected for around 1800 years. Here, we collected some present clans with full records of 70-100 generations claimed to be descendants of CAO Cao or CAO Can, and validated them by comparing their Y chromosomes. Haplotype O2-M268 is the only one that is enriched significantly in the Emperor's claimed descendant clans (P=9.323 × 10−5, odds ratio=12.72) and, therefore, is most likely to be that of the Emperor. Moreover, our analysis showed that the Y chromosome haplotype of the Emperor is different from that of the Marquis (Haplotype O3-002611). Therefore, Emperor CAO Cao's claim was not supported by genetic evidence. This study offers a successful showcase of the utility of genetics in studying the ancient history. [ABSTRACT FROM AUTHOR]

In epidemiological studies, it is easier to glean information from isolated populations with simple genetic backgrounds than from populations with relatively complex genetic backgrounds. Regarded as an isolated population, the Minz (Hei-Yi Zhuang) in Napo County (in the China-Vietnam borderland) has been the subject of numerous recent studies. To assess the genetic isolation of this population, we studied Y chromosome and mitochondrial DNA from Minz and Han in Napo. Both populations exhibited southern Chinese genetic characteristics in both paternal and maternal lineages. Using NETWORK analyses, we found pronounced gene flow between these two populations only in maternal lineages. We also observed gene flow from other populations into the Minz gene pool. We thus concluded that the Minz is not a genetically isolated population and it is increasingly difficult to find isolated populations in mainland East Asia. [ABSTRACT FROM AUTHOR]