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Locust swarms had periodically raged in both North American Plains (NAP) and East Asian Plains (EAP) before 1880 AD. After this period, the locust outbreaks almost never recurred in NAP but have continued to occur in EAP. Since large quantities of pesticides were used in the major agriculture regions of NAP in the late 1870s; this has been suggested as a possible major cause of the disappearing of locust outbreaks. Extensive applications of more effective chemical pesticides were also used in the granary regions of EAP in the 1950s in an effort to kill the pests at a much higher intensity. However, locust swarms came back again in many areas of China in the 1960s. Therefore, NAP locust extinction still remains a puzzle. Frequent locust outbreaks in EAP over the past 130 yr may offer clues to probe key control elements in the disappearing of locust outbreaks in NAP. This paper analyzes the climate extremes and monthly temperature-precipitation combines of NAP and EAP, and found the differences in their frequencies of these climate combines caused different locust fates in the two regions: restrained the locust outbreak in NAP but induced such events in EAP. Validation shows that severer EAP locust outbreak years were coincided with the climate extreme combines years. Thus we suggest that climate changes in frequency, extremes and trends can explain why the fate of the locust plague in EAP was different from that in NAP. The study also points out that, under the present global warming, cautions should be taken to make sure the pest hazard being nipped in the-bud. [ABSTRACT FROM AUTHOR]

Bridging the Pacific provides an image of two separate regions which share the Pacific Rim, becoming connected in multiple aspects, not limited to a predominantly economic interconnection. This image, thus, points toward a constructive mechanism to work toward a resolution of the over-arching global issue, including climate change. This image and the method for its practical implementation are suggested by the Forum for East Asia and Latin America Cooperation—FEALAC. In the overall field of regionalism studies, inter-regionalism can be considered as 'the third wave' under the new regionalism, and FEALAC can be located in this analytical framework. To begin, this paper traces the process and features of regionalism by typification of three different versions, or ideal types of regionalism. In this work, each type of regionalism is not viewed as a successor to, considered better than the previous one, but rather provides a typology for analytical purposes. Next, taking up this historical and analytical framework of regionalism, this paper examines the FEALAC in terms of its strengths and weaknesses considered from the perspective of the five systemic functions. Finally, this paper demonstrates the ways in which FEALAC can be considered a relevant framework of inter-regional governance. [ABSTRACT FROM AUTHOR]

This REgional Carbon Cycle Assessment and Processes regional study provides a synthesis of the carbon balance of terrestrial ecosystems in East Asia, a region comprised of China, Japan, North- and South-Korea, and Mongolia. We estimate the current terrestrial carbon balance of East Asia and its driving mechanisms during 1990-2009 using three di?erent approaches: inventories combined with satellite greenness measurements, terrestrial ecosystem carbon cycle models and atmospheric inversion models. The magnitudes of East Asia's natural carbon sink from these three approaches are comparable: -0.264±0.033 PgC yr-1 from inventory-remote sensing model-data fusion approach, -0.393±0.141 PgC yr-1 (not considering biofuel emissions) or -0.204±0.141 PgC yr-1 (considering biofuel emissions) for carbon cycle models, and -0.270±0.507 PgC yr-1 for atmospheric inverse models. The ensemble of ecosystem modeling based analyses further suggests that at the regional scale, climate change and rising atmospheric CO2 together resulted in a carbon sink of -0.289±0.135 PgC yr-1 , while land use change and nitrogen deposition had a contribution of -0.013±0.029 PgCyr and -0.107±0.025 PgC yr-1 , respectively. Although the magnitude of climate change effects on the carbon balance varies among different models, all models agree that in response to climate change alone, southern China experienced an increase in carbon storage from 1990 to 2009, while northern East Asia including Mongolia and north China showed a decrease in carbon storage. Overall, our results suggest that about 13-26% of East Asia's CO2 emissions from fossil fuel burning have been offset by carbon accumulation in its terrestrial ecosystems over the period from 1990 to 2009. The underlying mechanisms of carbon sink over East Asia still remain largely uncertain, given the diversity and intensity of land management processes, and the regional conjunction of many drivers such as nutrient deposition, climate, atmospheric pollution and CO2 changes, which cannot be considered as independent for their effects on carbon storage. [ABSTRACT FROM AUTHOR]

The article investigates the application of multi-angular total and polarized remote sensing for aerosol optical depth and fine-mode fraction retrieval in East Asia. It states that the algorithm retrieves aerosol optical depth (AOD), fine-mode fraction (FMF) for studying the climatic impact of aerosol. It indicates that the best features of aerosol model over East Asia are constrained using the cluster analysis technique based on the AERONET sun-photometer observation over East Asia.

The current paper first time describes a small Beremendia from the late Pleistocene deposits in the Koridornaya Cave locality (Russian Far East), which associated with the extinct Beremendia minor. The paper is the first attempt to use a comparative analytical method to evaluate a possible case of redeposition of fossil remains of this shrew. In this case, the 'comparative' part of the method corresponds to the 'faunistic approach' of Jelle Reumer, and the 'analytical' part of the method corresponds to his extended 'morphological approach. ' The analytic method uses morphospace size estimation (MSE) based on principal component analysis and estimation of the variance to evaluate redeposition of Beremendia minor from the late Pleistocene deposits in the Koridornaya Cave. This result allows us to suggest the significant environmental contribution to the East Asian beremendiin extinction, such as climatic fluctuation, landscape changes and shrew community changes between the late Pliocene and early Pleistocene. We discuss the last remains of East Asian Beremendia (Peisorex) described from the Chinese early Pleistocene localities (Chiachiashan, Haimao, Renzidong) and the last remains of Lunanosorex described from the Chinese late Pliocene localities (Qipanshan Hill and Houxushan Hill). MSE was performed for soricine tribes with the 'elongated' condylar process. [ABSTRACT FROM AUTHOR]

There are many types of atmospheric heat engines in land-air systems. The accurate definition, calculation and interpretation of the efficiency of atmospheric heat engines are key to understanding energy transfer and transformation of land-air systems. The atmosphere over the Qinghai-Tibet Plateau (QTP) in summer can be regarded as a positive heat engine. The study of the heat engine efficiency is helpful to better understand land-air interaction and thermal-dynamic processes on the QTP. It also provides a new perspective to explain the impact of the QTP on the climate of China, East Asia and even the world. In this paper, we used MOD08 and ERA5 reanalysis data to calculate the atmospheric heat engine efficiency, surface heat source and atmospheric heat source on the QTP in summer (May to September) from 2000 to 2020. The average atmospheric heat engine efficiency on the QTP in summer from 2000 to 2020 varies between 1.2% and 1.5%, which is less than 1.6%; the heat engine efficiency in summer is higher than that in June, July and August; the Qaidam Basin is the region with the highest atmospheric heat engine efficiency, followed by the western QTP. The mean surface heat source on the QTP in summer from 2000 to 2020 is 96.0 W m−2, the atmospheric heat source is 90.7 W m−2, and the release of precipitation condensation latent heat is the most important component of the atmospheric heat source on the QTP in summer. There is a strong and significant positive correlation between the atmospheric heat engine efficiency and the surface heat source on the QTP in summer. The precipitation con densation latent heat is the most important component of the atmospheric heat source in summer and can reflect the precipitation process. There is a strong and significant negative correlation between the atmospheric heat engine efficiency and the atmo spheric heat source on the QTP in summer. [ABSTRACT FROM AUTHOR]

This paper provides an updated analysis of observed changes in extreme precipitation using high-quality station data up to 2018. We examine changes in extreme precipitation represented by annual maxima of 1-day (Rx1day) and 5-day (Rx5day) precipitation accumulations at different spatial scales and attempt to address whether the signal in extreme precipitation has strengthened with several years of additional observations. Extreme precipitation has increased at about two-thirds of stations and the percentage of stations with significantly increasing trends is significantly larger than that can be expected by chance for the globe, continents including Asia, Europe, and North America, and regions including central North America, eastern North America, northern Central America, northern Europe, the Russian Far East, eastern central Asia, and East Asia. The percentage of stations with significantly decreasing trends is not different from that expected by chance. Fitting extreme precipitation to generalized extreme value distributions with global mean surface temperature (GMST) as a covariate reaffirms the statistically significant connections between extreme precipitation and temperature. The global median sensitivity, percentage change in extreme precipitation per 1 K increase in GMST is 6.6% (5.1% to 8.2%; 5%–95% confidence interval) for Rx1day and is slightly smaller at 5.7% (5.0% to 8.0%) for Rx5day. The comparison of results based on observations ending in 2018 with those from data ending in 2000–09 shows a consistent median rate of increase, but a larger percentage of stations with statistically significant increasing trends, indicating an increase in the detectability of extreme precipitation intensification, likely due to the use of longer records. [ABSTRACT FROM AUTHOR]

Meat production and consumption are major contributors to global greenhouse gas emissions and other aspects of environmental degradation. It is the aim of this paper to explore red meat in the configuration of main meals eaten out in England across types and styles of cuisine, and to consider the implications for transition towards less resource intensive ways of eating in the future. We show that the odds ratio of eating a dish without red meat is significantly lower in North American/European and Near/Middle Eastern cuisines compared with East Asian (with no difference between South and East Asian), that women are more likely than men to eat fish and poultry (with no gender differences in vegetarian dishes), that Prestonians are the least likely to select a vegetarian dish, compared with people in London and Bristol, and that the odds of a vegetarian dish compared with red meat is higher amongst managerial workers compared with the routine manual workers (with no other statistically significant class differences). We suggest the term "translated cuisine" to refer cuisines that travel and become incorporated into the palate of the new food culture, and discuss how this could play a role in transitions towards less meat‐centred patterns of food consumption in the future. [ABSTRACT FROM AUTHOR]

Climate and climate change have always been a research focus of atmospheric sciences. This paper summaries research efforts, achievements and international contributions of the Chinese scientific community on climate and climate change over the past 70 years. The review is based on papers published officially in national or international scientific journals, and is organized to cover six aspects: (1) general climate studies; (2) impact of the Qinghai-Tibetan Plateau; (3) impact of the East Asian monsoon; (4) influences of teleconnection oscillation and westerlies; (5) climate dynamics and development of climate models; and (6) climate change. It is, however, to be noted that the present review can not be considered as an exhaustive one, since there is a huge body of literature in the field. [ABSTRACT FROM AUTHOR]

The Asian monsoon influences the lives of more than a third of the world's population, and understanding its spatial and temporal variability is fundamental to sustainable development. The complex dynamics of this climatic system are therefore of broad scientific and societal interest. In this virtual special issue (VSI), we present 19 papers dealing with the Asian monsoon since the Last Glacial Maximum (LGM, ∼21 kyr BP), with a focus on understanding variability and forcing mechanisms. Findings use recently developed quantitative reconstructions combined with numerical simulations, and present novel insights as follows: (1) analyses of comprehensive datasets of pollen, diatom, brGDGTs, oxygen and hydrogen isotopes and frequency magnetic susceptibility, as well as an innovative algorithm model for the lake energy-water balance, improve the reliability of quantitative reconstructions of Asian monsoon climate variations; (2) studies of quantitative climate parameters in central East Asia show that mean annual temperature (MAT) was ∼5 °C (or ∼ 7.9 °C using brGDGTs) lower during the LGM, ∼1.5 °C (±41% using brGDGTs) higher around the Holocene thermal optimum (HO) and mean annual precipitation (MAP) varied between 30 and 150% with marked seasonality during 8–5 ka; (3) dynamical downscaling palaeoclimatic simulations improve the accuracy of past monsoon variations, revealing strong variability in monsoon precipitation across the LGM and HO. The holistic study of Asian monsoon variations at orbital to centennial timescales in these VSI papers presents reliable observations of monsoon variability and its driving mechanisms, providing high-resolution quantitative paleoclimate reconstructions that fill existing gaps in spatial coverage, as well as offering an improved understanding, thorough numerical simulation, of coupled sea-level change and vegetation feedbacks. • An introduction to Asian monsoon variations over the past 21 ka. • Transfer functions, sedimentary records and numerical simulation are developed for studying past Asian monsoon. • Averaged MAP in East Asia varied between 30-150 % over the past 21 ka. [ABSTRACT FROM AUTHOR]

This paper presents two new pollen records and quantitative climate reconstructions from northern Chukotka documenting environmental changes over the last 27.9 ka. Open tundra‐ and steppe‐like habitats dominated between 27.9 and 18.7 cal. ka BP. Betula and Alnus shrubs might have grown in sheltered microhabitats but disappeared after 18.7 cal. ka BP. Although the climate was rather harsh, local herb‐dominated communities supported herbivores as is evident by the presence of coprophilous spores in the sediments. The increase in Salix and Cyperaceae ~16.1 cal. ka BP suggests climate amelioration. Shrub Betula appeared ~15.9 cal. ka BP, and became dominant after ~15.52 cal. ka BP, whilst typical steppe communities drastically reduced. Very high presence of Botryococcus in the Lateglacial sediments reflects widespread shallow habitats, probably due to lake level increase. Shrub Alnus became common after ~13 cal. ka BP reflecting further climate amelioration. Simultaneously, herb communities gradually decreased in the vegetation reaching a minimum ~11.8 cal. ka BP. A gradual decrease of algae remains suggests a reduction of shallow‐water habitats. Shrubby and graminoid tundra was dominant ~11.8–11.1 cal. ka BP, later Salix stands significantly decreased. The forest‐tundra ecotone established in the Early Holocene, shortly after 11.1 cal. ka BP. Low contents of green algae in the Early Holocene sediments likely reflect deeper aquatic conditions. The most favourable climate conditions were between ~10.6 and 7 cal. ka BP. Vegetation became similar to the modern after ~7 cal. ka BP but Pinus pumila came to the Ilirney area at about 1.2 cal. ka BP. It is important to emphasize that the study area provided refugia for Betula and Alnus during MIS 2. It is also notable that our records do not reflect evidence of Younger Dryas cooling, which is inconsistent with some regional environmental records but in good accordance with some others. [ABSTRACT FROM AUTHOR]

This paper documents changes in three villages of the Ponoy River region, Murmansk, Russia between 2006 and 2020. Two keystone species—the Atlantic salmon (Salmo salar) and northern pike (Esox lucius) as well as an introduced species, the pink salmon (Oncorhynchus gorbuscha), were studied to determine changes to fish and fisheries. Oral histories, community-based observations and literature data are used to establish key messages on river health from the 1800s to 2020, including temperature data from 1864 to present. Climate change becomes increasingly evident and impacts the Ponoy River system from 1980s onwards with system-relevant changes becoming more pronounced in late 2010s. This coincides with proliferation of pink salmon from 2006 onwards. The species was introduced from the Russian Far East in the 1930s. Very few long-term community-based observation processes have taken place in the Russian North and this paper corrects this to certain extent. Ponoy River and region are important as the last major roadless wilderness area of the European North. Societal and climate changes are rapidly impacting the river and its catchment area as well as the available biological resources and consequently the local culture. This study shows the value of local communities to determine base lines and highlight ongoing changes when establishing climate change impacts and impacts of an alien species. [ABSTRACT FROM AUTHOR]

This paper engages key social theories of transnational mobilities in order to forge the concept of urban 'green' cosmopolitization, posited as a social scientifi c contribution to epochal conversations on climate change. Bringing Ulrich Beck's notion of 'cosmopolitization' to bear on recent work around 'urban policy mobilities', I analyze professional planning practices in large-scale world cities as privileged sites for contemporary imaginings and material implementations of low-carbon sociotechnical change. Focusing on the regions of Europe and Asia, I show how specifi c policies and technologies of urban greening circulate in intercity sustainability networks. These networks, I suggest, serve to organize processes of professional engagement with climate change around notions of innovation, learning, and 'best practice' policy transfer among urban professionals--thereby also excluding more 'radically' alternative futures. The paper then turns to explore how such green cosmopolitization works as a social force within specifi c urban localities, employing two ethnographic case studies into 'ambitious' low-carbon planning projects in Copenhagen and Kyoto, respectively. In particular, my analysis explores how place-based notions of 'culture' are mobilized in the urban visions of architects and engineers as resources for addressing global environmental risks. These spaces of urban green cosmopolitization, I conclude, emerge at the intersection of professional and vernacular ethico-political attachments, thereby reworking--in often contentious ways--how particular urban materials and spaces can be understood in reference to an emerging moral geography of shared climatic risks. [ABSTRACT FROM AUTHOR]

The atmospheric moisture transport processes are of great importance to the occurrence and intensity of precipitation extremes. In this paper, we review the linkage between processes, including the large‐scale atmospheric circulation, atmospheric moisture transport, and extreme precipitation events. We first summarize the thermodynamic and dynamic processes and moisture transport trackings for historical precipitation extremes. We then focus on the contribution of three major atmospheric moisture transport pathways, that is, atmospheric rivers, low‐level jets, and tropical cyclones, to the occurrence and intensity of regional precipitation extremes. Studies on large‐scale atmospheric circulation driving water vapor transport for precipitation extremes over East Asia and North America were specifically reviewed for the understanding of physical mechanisms and predictability of moisture transport and extreme precipitation events. We then pay more attention to the effects of global warming on atmospheric moisture transport, and thus regional precipitation extremes from the perspectives of thermodynamic and dynamic changes of the atmosphere. In the end, we summarize future research challenges on the physical mechanisms of atmospheric moisture transport that are associated with regional precipitation extremes, especially under a warming climate. This article is categorized under: Science of Water > Water ExtremesScience of Water > Hydrological Processes [ABSTRACT FROM AUTHOR]

This paper analyzes climatological characteristics and temporal variation of the start and end dates of the rainy season over East Asia using a daily precipitation dataset for the time period 1951-2009. The rainy season is defined by a 5-day rainfall standard, and the regional average time series is constructed by applying the weighted-average method. Results show that the rainy season starts later, ends earlier and lasts shorter from southeast to northwest. In spring, the rainy belt slowly moves northward from 30 to 33°N in China and from 33 to 36°N on the Korean Peninsula and Japanese Islands. From 1951 to 2009, the rainy season generally began earlier in China but later in Korea and Japan, and it ended earlier at latitudes north of 35°N and later south of 35°N. The region-averaged start and end dates of the rainy season in the study region insignificantly advanced, and the duration of the rainy season insignificantly increased from 1951 to 2009. The rainy season duration slightly decreased in the Russian Far East and in northern and western China, and significantly decreased on the Korean Peninsula and the southern Hokkaido Islands, though it obviously increased in the Yangtze--Huaihe River Basins. [ABSTRACT FROM AUTHOR]

40% of global population, who resides in Asian monsoon region is at high risk from extreme hot summer events, which is expected to increase by 25%/30 years under RCP8.5 scenario. Using Community Earth System Model (CESM) Large-ensemble simulations we assess the relative contribution of external forcings and internal variability on hot extremes over South and East Asia. Climate change projects surface mean temperature to reach 2.0 °C and 5.0 °C by ~2050 and ~2100, respectively, making the region uninhabitable under exposed conditions. Internal variability will partly obscure anthropogenic warming over South and Southeast Asia; however, East Asia will experience a 4–6 fold rise in record breaking hot events in later periods. Nevertheless, beyond 2.35 °C warming internal variability will decrease over South Asia due to weaker albedo feedback on unforced internal variability. Our results contradict the existing hypothesis that warming will increase volatility in weather patterns everywhere, particularly the Asian monsoon regions. [ABSTRACT FROM AUTHOR]

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The present paper examined the teleconnections between two huge Asian summer monsoon components (South and East Asia) during three time slices in future: near-(2010–2039), mid-(2040–2069) and far-(2070–2100) futures under the RCP4.5 and RCP8.5 scenarios. For this purpose, a high-resolution atmospheric general circulation model is used and integrated at 40 km horizontal resolution. To get more insight into the relationships between the two Asian monsoon components, we have studied the spatial displaying correlation coefficients (CCs) pattern of precipitation over the entire Asian monsoon region with that of South Asia and three regions of East Asia (North China, Korea–Japan and Southern China) separately during the same three time slices. The possible factors responsible for these teleconnections are explored by using mean sea level pressure (MSLP) and wind fields at 850 hPa. The CC pattern of precipitation over South Asia shows an in-phase relationship with North China and an out-of-phase relationship with Korea–Japan, while precipitation variations over Korea–Japan and Southern China exhibit an out-of-phase relationship with South Asia. The CCs analysis between the two Asian blocks during different time slices shows the strongest CCs during the near and far future with the RCP8.5 scenario. The CC pattern of precipitation over Korea–Japan and Southern China with the wind (at 850 hPa) and MSLP fields indicate that the major parts of the moisture over Korea–Japan gets transported from the west Pacific along the western limb of NPSH, while the moisture over Southern China comes from the Bay of Bengal and South China Seas for good monsoon activity. [ABSTRACT FROM AUTHOR]

This paper argues that to understand the relevance of developmental states in East Asia and elsewhere, we need to focus on the changing development agenda in the early twenty-first century, especially how this connects with the global challenge of climate change and thereby sustainable, low-carbon development. It combines theories on state capacity and ecological modernisation to form the 'new developmentalism' concept. This is applied to study revitalised and refocused forms of state capacity aimed at realising the transformative economic objectives associated with sustainable development. New developmentalism helps us understand not only current state capacity practice in a climate challenged world but also how we have moved beyond original conceptions of developmental statism. It may be understood in the wider context of the sustainable development agenda and climate interventionism. As is argued, new developmentalism is most clearly evident in East Asia but can be applied in a wider geographic sense where strong forms of developmental state capacity are exercised towards meeting transformative sustainable development goals. [ABSTRACT FROM AUTHOR]

There are growing needs to broaden and deepen our multi-faceted understanding of the ecosystems, and the networks of Long-Term Ecological Research (LTER) can play significant roles in fostering and applying ecosystem studies at regional and global scales. The International LTER Network (ILTER) is organized as a global network of field research sites and scientists to address current ecological issues such as biodiversity loss and ecosystem degradation within a globally changing environment. The ILTER East Asia-Pacific Regional Network (ILTER-EAP) is one of the four constituent ILTER regional networks. Since 1995, ILTER-EAP has been developed to promote data sharing, research collaborations and capability building in the science and to bridge gaps between societal needs and scientific imperatives on concerns in the Asia-Pacific Region. Currently, ILTER-EAP comprises nine formal ILTER members and two associate networks. Their activities involve long-term and multiple-site observations of structural, functional and developmental aspects of ecosystems, data sharing, and bridging society and ecological science. This paper presents a review of the activities of ILTER-EAP, focusing on its: (1) vision and the development following its inception, (2) scientific activities and major outputs related to selected thematic areas, (3) contributions from ILTER-EAP to the international initiatives, and (4) future challenges and opportunities relating to its development and role in facilitating regional and global research collaborations. Accordingly, regional research questions were identified that could be most effectively addressed by opening up a common research platform, integrated data management system and the network science, which is open to all interested parties. [ABSTRACT FROM AUTHOR]

Cold extremes have large impacts on human society. Understanding the physical processes dominating the changes in cold extremes is crucial for a reliable projection of future climate change. The observed cold extremes have decreased during the last several decades, and this trend will continue under future global warming. Here, we quantitatively identify the contributions of dynamic (changes in large-scale atmospheric circulation) and thermodynamic (rising temperatures resulting from global warming) effects to East Asian cold extremes in the past several decades and in a future warm climate by using two sets of large-ensemble simulations of climate models. We show that the dynamic component accounts for over 80 % of the cold-month (coldest 5 % boreal winter months) surface air temperature (SAT) anomaly over the past 5 decades. However, in a future warm climate, the thermodynamic change is the main contributor to the decreases in the intensity and occurrence probability of East Asian cold extremes, while the dynamic change is also contributive. The intensity of East Asian cold extremes will decrease by around 5 °C at the end of the 21st century, in which the thermodynamic (dynamic) change contributes approximately 75 % (25 %). The present-day (1986–2005) East Asian cold extremes will almost never occur after around 2035, and this will happen 10 years later due solely to thermodynamic change. The upward trend of a positive Arctic Oscillation-like sea level pressure pattern dominates the changes in the dynamic component. The finding provides a useful reference for policymakers in climate change adaptation activities. [ABSTRACT FROM AUTHOR]

Reliable attribution of Asian summer monsoon variations to aerosol forcing is critical to reducing uncertainties in future projections of regional water availability, which is of utmost importance for risk management and adaptation planning in this densely populated region. Yet, simulating the monsoon remains a challenge for climate models that suffer from long-standing biases, undermining their reliability in attributing anthropogenically forced changes. We analyze a suite of climate model experiments to identify a link between model biases and monsoon responses to Asian aerosols and associated physical mechanisms, including the role of large-scale circulation changes. The aerosol impact on monsoon precipitation and circulation is strongly influenced by a model's ability to simulate the spatio-temporal variability in the climatological monsoon winds, clouds, and precipitation across Asia, which modulates the magnitude and efficacy of aerosol–cloud–precipitation interactions, an important component of the total aerosol response. There is a strong interplay between South Asia and East Asia monsoon precipitation biases and their relative predominance in driving the overall monsoon response. We found a striking contrast between the early- and late-summer aerosol-driven changes ascribable to opposite signs and seasonal evolution of the biases in the two regions. A realistic simulation of the evolution of the large-scale atmospheric circulation is crucial to realize the full extent of the aerosol impact over Asia. These findings provide important implications for better understanding and constraining the diversity and inconsistencies of model responses to aerosol changes over Asia in historical simulations and future projections. [ABSTRACT FROM AUTHOR]

East Asia is a region that is highly vulnerable to drought disasters during the spring season, as this period is critical for planting, germinating, and growing staple crops such as wheat, maize, and rice. The climate in East Asia is significantly influenced by three large-scale climate variations: the Pacific Decadal Oscillation (PDO), the El Niño–Southern Oscillation (ENSO), and the Indian Ocean Dipole (IOD) in the Pacific and Indian Oceans. In this study, the spring meteorological drought was quantified using the standardized precipitation evapotranspiration index (SPEI) for March, April, and May. Initially, coupled climate networks were established for two climate variables: sea surface temperature (SST) and SPEI. The directed links from SST to SPEI were determined based on the Granger causality test. These coupled climate networks revealed the associations between climate variations and meteorological droughts, indicating that semi-arid areas are more sensitive to these climate variations. In the spring, PDO and ENSO do not cause extreme wetness or dryness in East Asia, whereas IOD does. The remote impacts of these climate variations on SPEI can be partially explained by atmospheric circulations, where the combined effects of air temperatures, winds, and air pressure fields determine the wet/dry conditions in East Asia. [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]

The Indo-Pacific, a vast biogeographic of Earth, is influenced by both the Indian and East Asian monsoons. Despite its geographical importance, this region has been less studied compared to East Asia and India. Here, we present speleothem records from southern Thailand that cover the last 1500 years, including a hiatus during the Little Ice Age, providing insights into the interactions among climate dynamics, human influences, and ecological responses to climate change. Notably, our records lack the characteristic cold and warm periods observed in other regions, such as the Dark Ages Cold Period and Medieval Warm Period, which may reflect the complexity of the tropical climate system or the region's unique topography. The analysis reveals a link between ENSO multi-decadal variability and hydroclimate conditions in southern Thailand, as evidenced by speleothem δ18O. Furthermore, a comparison between speleothem δ13C and the Normalized Difference Vegetation Index (NDVI) indicates significant vegetation changes in the last three decades, corresponding with increased atmospheric CO2 levels and expansion of agricultural land due to human activities during the Current Warm Period. Additionally, our study suggests that an abrupt increase in sea surface temperatures may enhance vegetation growth in the Indo-Pacific by influencing atmospheric circulation and increasing precipitation. [ABSTRACT FROM AUTHOR]

Wildfires emit atmospheric aerosols, affecting climate and air quality. Siberia is a known source region of wildfires. However, comprehensive knowledge regarding the impact associated with particulate matter pollution due to Siberian wildfires on climate and air quality and their effects on mortality and the economy under present and near‐future warmer atmospheric conditions remains poor. Thus, we performed model sensitivity experiments (atmospheric model and coupled atmosphere‐ocean model settings) simulating the effects of changing Siberian wildfire emissions under the present and near‐future climate conditions, using the Model for Interdisciplinary Research on Climate version 5 (MIROC5). Increased Siberian wildfire smoke likely caused a cooling effect in broad areas of the Northern Hemisphere and worsened the air quality near the source and in the downwind region (i.e., East Asia). The more Siberian wildfires occur, the more air pollution is present in those regions, which likely increases mortality and welfare losses there. However, the total impact of changing temperature on the gross domestic product under present and near‐future climate conditions is ambiguous. Our comprehensive results on the air quality changes due to Siberian wildfires under present and near‐future climate conditions suggest that increased efforts to limit the aerosol impact of Siberian wildfires are crucial to prevent possible excess mortality and economic losses. Plain Language Summary: Comprehensive knowledge of worsening air quality due to increased Siberian wildfires and its impact on climate and economy is needed to assess the impact of such fires both near their source and in the surrounding regions. Therefore, we performed global climate model simulations and analyzed the changing atmospheric aerosol emissions, including a precursor gas, from Siberian wildfires under the present and near‐future climate conditions using the Japanese global climate model called MIROC5. The increased aerosol emissions from Siberian wildfires generated a cooling effect in broad areas of the Northern Hemisphere and worsened the air quality near the source and in the downwind areas of East Asia. The effects we observed are associated with excess mortality and economic welfare losses. Future studies are needed to fully understand and prevent those negative impacts. Key Points: Comprehensive impacts of increasing Siberian wildfires on air quality, climate, and economy were estimated using the MIROC5 climate modelWe observed a cooling effect broadly across the Northern Hemisphere and worsened air quality near wildfire source and downwind regionsThe effects are closely related to lowering achievement rates of PM2.5 environmental standards, excess mortality, and economic losses [ABSTRACT FROM AUTHOR]

The East Asian winter monsoon (EAWM) is characterized by the frequent cold surges and associated closely with the Siberia High, East Asian Trough, and high-level westerly jet stream. The ENSO cycle can modulate the EAWM since it has co-variability with the sea surface temperature over the Indo-Western-Pacific which can tune the land-sea thermal contrast for the EAWM. This paper, by analyzing the EAWM, ENSO, and associated atmosphere-ocean variability, documents the weakening of the EAWM-ENSO relationship after the 1970s. The significant out-of-phase inter-relationship is found to be diminished after the 1970s. Further study in this work suggests that the weakened co-variability of the tropical Indo-Western-Pacific climate associated with ENSO after the 1970s is partly responsible for the weakened inter-relationship. Meanwhile, the reduced EAWM interannual variability and northward retreat of the EAWM-associated climate variability are favorable to the weakened ENSO-EAWM connection. [ABSTRACT FROM AUTHOR]

Recent advances in the study of the characteristics, processes, and causes of spatio-temporal variabilities of the East Asian monsoon (EAM) system are reviewed in this paper. The understanding of the EAM system has improved in many aspects: the basic characteristics of horizontal and vertical structures, the annual cycle of the East Asian summer monsoon (EASM) system and the East Asian winter monsoon (EAWM) system, the characteristics of the spatio-temporal variabilities of the EASM system and the EAWM system, and especially the multiple modes of the EAM system and their spatio-temporal variabilities. Some new results have also been achieved in understanding the atmosphere-ocean interaction and atmosphere-land interaction processes that affect the variability of the EAM system. Based on recent studies, the EAM system can be seen as more than a circulation system, it can be viewed as an atmosphere-ocean-land coupled system, namely, the EAM climate system. In addition, further progress has been made in diagnosing the internal physical mechanisms of EAM climate system variability, especially regarding the characteristics and properties of the East Asia-Pacific (EAP) teleconnection over East Asia and the North Pacific, the “Silk Road” teleconnection along the westerly jet stream in the upper troposphere over the Asian continent, and the dynamical effects of quasi-stationary planetary wave activity on EAM system variability. At the end of the paper, some scientific problems regarding understanding the EAM system variability are proposed for further study. [ABSTRACT FROM AUTHOR]

The impact of climate change on the circumpolar north has raised the profile of the Arctic Ocean to coastal states and presents serious foreign policy challenges. Chief among these is the pending delimitation dispute over the extended continental shelf between Canada, Denmark, the United States, and Russia. While delimitation disputes are not new to Arctic states, extended continental shelf claims are complicated by the existence of multiple claimants and a still developing international legal regime. To inform policymakers about what to expect from overlapping claims to disputed maritime areas, this paper draws comparative lessons for Arctic policymakers based on East Asia's experience responding to overlapping jurisdictional entitlements created by the UN Convention on the Law of the Sea (UNCLOS). East Asian states have been grappling with the challenge presented by overlapping claims to resource-rich seabeds since the region ratified UNCLOS in the mid-late 1990s. In light of similar geographic conditions (a dispute over a semi-enclosed sea), alliance structures and the relative infancy of the claimant states with UNCLOS entitlements-Canada only ratified the treaty in 2003, and the United States has yet to do so-this paper sets out the case that important comparative lessons can be drawn from the East Asian experience with maritime delimitation disputes. [ABSTRACT FROM AUTHOR]

Droughts have become more severe and frequent due to global warming. In this context, it is widely accepted that for drought assessments, both water supply (rainfall) and demand (standardized precipitation evapotranspiration index, SPEI) should be considered. Using SPEI, we explored the spatial-temporal patterns of dry and wet annual and seasonal changes in five sub-regions of East Asia during 1902–2018. These factors are linked to excess drought frequency and severity on the regional scale, and their effect on vegetation remains an important topic for climate change studies. Our results show that the SPEI significantly improved extreme drought and mostly affected the SPEI-06 and SPEI-12 growing seasons in East Asia during 1981–2018. The dry and wet annual SPEI trends mostly affect the five sub-regions of East Asia. The annual SPEI had two extremely dry spells during 1936–1947 and 1978–2018. Japan, South Korea, and North Korea are wet in the summer compared to other regions of East Asia, with drought frequency occurring at 51.4%, respectively. The mean drought frequencies in China and Mongolia are 57.4% and 54.6%. China and Mongolia are the driest regions in East Asia due to high drought frequency and duration. The spatial seasonal analysis of solar radiation (SR), water vapor pressure (WVP), wind speed (WS), vegetation condition index (VCI), temperature condition index (TCI), and vegetation health index (VHI) have confirmed that the East Asia region suffered from maximum drought events. The seasonal variation of SPEI shows no clear drying trends during summer and autumn seasons. During the winter and spring seasons, there was a dry trend in East Asia region. During 1902–1990, a seasonal SPEI presented diverse characteristics, with clear wet trends in Japan, Mongolia, and North Korea in four different growing seasons, with dry trends in China and South Korea. During 1991–2018, seasonal SPEI presented clear dry trends in Japan, Mongolia, and North Korea in different growing seasons, while China and South Korea showed a wet trend during the spring, autumn, and winter seasons. This ecological and climatic mechanism provides a good basis for the assessment of vegetation and drought-change variations within East Asia. An understandings of long-term vegetation trends and the effects of rainfall and SPEI on droughts of varying severity is essential for water resource management and climate change adaptation. Based on the results, water resources will increase under global warming, which may alleviate the water scarcity issue in the East Asia region. [ABSTRACT FROM AUTHOR]

Based on outputs of 28 coupled models from the Phase 6 of the Coupled Model Intercomparison Project (CMIP6), we show that the response of the Southeast Asian summer monsoon to the El Niño‐Southern Oscillation (ENSO) during post‐ENSO summer will likely strengthen in a warmer climate, which can be attributed to concurrently weakened sea‐surface temperature anomalies (SSTAs) in the western equatorial Pacific (WEP). The weakened WEP SSTAs are primarily caused by enhanced latent heat damping due to increased surface wind speed anomalies, which are associated with the eastward shift of the El Niño‐induced anomalous Walker circulation due to El Niño‐like sea surface temperature change in the tropical Pacific under global warming. Besides, the climatological zonal ocean currents will slow down due to the weakening of climatological Walker circulation, which also acts to weaken the WEP SSTAs via reducing the advection of anomalous temperature by the mean current. Plain Language Summary: As an important component of the Asian monsoon system, the Southeast Asian summer monsoon (SEASM) is crucial for the livelihoods of billions of people in East Asia, and is closely connected to a climate phenomenon called El Niño‐Southern Oscillation (ENSO). Understanding how the relationship between SEASM and ENSO will change in the future is important for enhancing our knowledge of climate change in East Asia. Outputs of 28 climate models from the Phase 6 of the Coupled Model Intercomparison Project show that ENSO will exert enhanced impacts on the SEASM in a warmer climate. The enhanced influences of ENSO on the monsoon will exacerbate the reduction of rainfall over the western North Pacific during the post‐El Niño summer. We find that such projected changes are mainly caused by weakened warm sea surface temperature (SST) anomalies (SSTAs) in the western equatorial Pacific (WEP). Further analyses indicate that the change in WEP SSTAs can be linked to the El Niño‐like change in climatological SSTs in the tropical Pacific. This study depicts detailed physical processes responsible for the projected changes in ENSO's impacts on the SEASM. Key Points: The effects of the El Niño‐Southern Oscillation on the Southeast Asian summer monsoon will strengthen under global warmingThe enhanced El Niño's impacts result from the weakened warm sea‐surface temperature (SST) anomalies in the western equatorial Pacific (WEP)The weakened WEP SST anomalies are related to the eastward shift of anomalous Walker circulation and the slackened mean zonal ocean currents [ABSTRACT FROM AUTHOR]

Populations of Eurasian otters Lutra lutra, one of the most widely distributed apex predators in Eurasia, have been depleted mainly since the 1950s. However, a lack of information about their genomic diversity and how they are organized geographically in East Asia severely impedes our ability to monitor and conserve them in particular management units. Here, we re‐sequenced and analyzed 20 otter genomes spanning continental East Asia, including a population at Kinmen, a small island off the Fujian coast, China. The otters form three genetic clusters (one of L. l. lutra in the north and two of L. l. chinensis in the south), which have diverged in the Holocene. These three clusters should be recognized as three conservation management units to monitor and manage independently. The heterozygosity of the East Asian otters is as low as that of the threatened carnivores sequenced. Historical effective population size trajectories inferred from genomic variations suggest that their low genomic diversity could be partially attributed to changes in the climate since the mid‐Pleistocene and anthropogenic intervention since the Holocene. However, no evidence of genetic erosion, mutation load, or high level of inbreeding was detected in the presumably isolated Kinmen Island population. Any future in situ conservation efforts should consider this information for the conservation management units. [ABSTRACT FROM AUTHOR]

To address the problems and limitations identified through a comprehensive evaluation in Part I paper, several modifications are made in model inputs, treatments, and configurations and sensitivity simulations with improved model inputs and treatments are performed in this Part II paper. The use of reinitialization of meteorological variables reduces the biases and increases the spatial correlations in simulated temperature at 2-m (T2), specific humidity at 2-m (Q2), wind speed at 10-m (WS10), and precipitation (Precip). The use of a revised surface drag parameterization further reduces the biases in simulated WS10. The adjustment of only the magnitudes of anthropogenic emissions in the surface layer does not help improve overall model performance, whereas the adjustment of both the magnitudes and vertical distributions of anthropogenic emissions shows moderate to large improvement in simulated surface concentrations and column mass abundances of species in terms of domain mean performance statistics, hourly and monthly mean concentrations, and vertical profiles of concentrations at individual sites. The revised and more advanced dust emission schemes can help improve PM predictions. Using revised upper boundary conditions for O 3 significantly improves the column O 3 abundances. Using a simple SOA formation module further improves the predictions of organic carbon and PM 2.5 . The sensitivity simulation that combines all above model improvements greatly improves the overall model performance. For example, the sensitivity simulation gives the normalized mean biases (NMBs) of −6.1% to 23.8% for T2, 2.7–13.8% for Q2, 22.5–47.6% for WS10, and −9.1% to 15.6% for Precip, comparing to −9.8% to 75.6% for T2, 0.4–23.4% for Q2, 66.5–101.0% for WS10, and 11.4%–92.7% for Precip from the original simulation without those improvements. It also gives the NMBs for surface predictions of −68.2% to −3.7% for SO 2 , −73.8% to −20.6% for NO 2 , −8.8%–128.7% for O 3 , −61.4% to −26.5% for PM 2.5 , and −64.0% to 7.2% for PM 10 , comparing to −84.2% to −44.5% for SO 2 , −88.1% to −44.0% for NO 2 , −11.0%–160.3% for O 3 , −63.9% to −25.2% for PM 2.5 , and −68.9%–33.3% for PM 10 from the original simulation. The improved WRF/Chem is applied to estimate the impact of anthropogenic aerosols on regional climate and air quality in East Asia. Anthropogenic aerosols can increase cloud condensation nuclei, aerosol optical depth, cloud droplet number concentrations, and cloud optical depth. They can decrease surface net radiation, temperature at 2-m, wind speed at 10-m, planetary boundary layer height, and precipitation through various direct and indirect effects. These changes in turn lead to changes in chemical predictions in a variety of ways. [ABSTRACT FROM AUTHOR]

A key component of the East Asian climate system is seasonally varying monsoon wind. Its interannual and interdecadal variability, as well as underlying oceanic processes, is the subject of a recent project completed by the Chinese Academy of Sciences. A series of research progress in the areas of monsoon winds, ocean responses, upwelling and productivity has been made and reviewed by this paper. [ABSTRACT FROM AUTHOR]

The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades, including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate. Paleo, observational and modelling studies are covered to summarize several major themes, including: the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era, as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response (e.g., atmospheric circulation, air temperature) to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research. [ABSTRACT FROM AUTHOR]

Land-sea surface air temperature (SAT) contrast, an index of tropospheric thermodynamic structure and dynamical circulation, has shown a significant increase in recent decades over East Asia during the boreal summer. In Part I of this two-part paper, observational data and the results of transient warming experiments conducted using coupled atmosphere-ocean general circulation models (GCMs) are analyzed to examine changes in land-sea thermal contrast and the associated atmospheric circulation over East Asia from the past to the future. The interannual variability of the land-sea SAT contrast over the Far East for 1950-2012 was found to be tightly coupled with a characteristic tripolar pattern of tropospheric circulation over East Asia, which manifests as anticyclonic anomalies over the Okhotsk Sea and around the Philippines, and a cyclonic anomaly over Japan during a positive phase, and vice versa. In response to CO increase, the cold northeasterly winds off the east coast of northern Japan and the East Asian rainband were strengthened with the circulation pattern well projected on the observed interannual variability. These results are commonly found in GCMs regardless of future forcing scenarios, indicating the robustness of the East Asian climate response to global warming. The physical mechanisms responsible for the increase of the land-sea contrast are examined in Part II. [ABSTRACT FROM AUTHOR]

Exploring prehistoric variation in human–environmental interaction is critical for understanding the historical patterns and mechanisms of long-term human–land evolution. In this paper we review the published radiocarbon and optically stimulated luminescence (OSL) data from Late Paleolithic, Neolithic and Bronze Age sites in China, analyze the spatial–temporal distribution of these sites, and compare it with the results of recent paleoclimatic and archaeological studies. We seek to study the trajectory and influencing factors of human–environmental interactions in late prehistoric China. We detect changing patterns in the relationship between humans and the environment during different phases of the prehistoric era in China. Climate change clearly affected the environment of hunter-gatherer groups between 50,000–10,000 BP (before present, defined as 1950AD), and variation in human population in Neolithic China (∼10,000–4000 BP) was likely influenced primarily by the development of agriculture, in addition to substantial climate events. The spatial scale of human settlements expanded in the Bronze Age (∼4000–2200 BP) in a period of cooling climate. During this time the impact of human activities on the environment increased significantly, primarily caused by technological innovations related to the onset of prehistoric transcontinental cultural exchange in Eurasia. [ABSTRACT FROM AUTHOR]

For the comprehensive estimation of regional climate change over East Asia (EA) at the 2 and 3 °C global warming levels (GWLs), the Köppen‐Trewartha climate‐type change is assessed with ensemble regional climate change projections in line with Coordinated Regional Climate Downscaling Experiment (CORDEX)‐EA phase 2. Under the 2 °C (3 °C) GWL, 17.6% (25.2%) of the EA region is expected to undergo major climate‐type changes. Tropical and subtropical climate types will expand northward, accompanied by increasing hydroclimatic intensity. Limiting GWL to 2 °C shows benefits by preventing subtropical‐type expansion around far EA. Desertification over inland regions of EA exhibits scenario dependency. Boreal and tundra climate types over high‐latitude regions will tend to decrease rapidly, especially over the Tibetan Plateau. The results are expected to be a baseline assessment of climate change over EA under the 2 and 3 °C GWLs above the preindustrial level. Plain Language Summary: This paper investigates the Köppen‐Trewartha climate‐type changes over East Asia (EA) at the 2 and 3 °C global warming levels (GWLs) with the ensemble regional climate simulations. Under the 2 °C (3 °C) GWL, 17.6% (25.2%) of the EA region is expected to undergo major climate‐type changes. The result shows increased tropical, subtropical, and desert climate types accompanied by intensification of hydroclimatic stress. In addition, boreal and tundra climate types over high‐latitude regions will tend to decrease rapidly, especially over the Tibetan Plateau under the 2 and 3 °C GWLs. Key Points: Baseline assessment of climate change over East Asia under the 2 and 3 °C global warming is here presentedOf the East Asia region, 17.6% (25.2%) is expected to experience major climate‐type changes under the 2 and 3 °C global warmingThe changes are accompanied by intensified hydroclimatic stress and have statistically significant trends until the end of the 21st century [ABSTRACT FROM AUTHOR]

The oxidation of sulfur dioxide (SO2) to sulfate in the atmosphere is an important concern in regional air quality, global climate change, and human health. While gas-phase and liquid-phase oxidation of SO2 are widely regarded as important sources of sulfate, the contribution of the heterogeneous oxidation process on particle surfaces is controversial. Recently, this heterogeneous chemistry has been considered to be an important mechanism that is missing in current models to explain sulfate concentrations observed in haze episodes in East Asia. Therefore, the heterogeneous oxidation of SO2 on particles under the conditions of complex air pollution needs to be reassessed. This review summarizes the fundamental understanding of the heterogeneous reactions of SO2 on solid particles such as mineral dust, black carbon, sea salts, organic aerosol, and so on. The factors affecting the mechanism and kinetics of the heterogeneous reactions of SO2, including coexisting components (O3, NO2, H2O2, NH3, and VOCs), reactive sites, surface properties, relative humidity, and illumination, are reviewed. Reactive oxygen species involved in the heterogeneous oxidation of SO2 on particles are discussed. To our knowledge, while previous reviews have appeared on the oxidation of SO2 in the aqueous-phase, this is the first review on the atmospheric heterogeneous reactions of SO2 on the surface of solid particles, which can be of help in understanding the sulfur cycle in the atmosphere and its environmental impacts. A number of recommendations for future research are also presented. [ABSTRACT FROM AUTHOR]

In the context of global climate change, recent studies indicate a poleward migration trend of tropical cyclones (TCs) in the western North Pacific (WNP), while little attention has been paid to the TC cyclolysis (hereafter Lysis). With respect to two different datasets, this study identifies the poleward migration of the annual-mean latitude of TC Lysis during 1979-2018, being more significant for the intensified TCs, although this trend is suppressed by the reduction in the TC frequency over the sea. It is found that the TC migration is more like a poleward translation of the overall movement rather than the expansion of a specific phase's distance span. Subsequently, the trends of several environmental parameters related to TC development are also analyzed. The large-scale sea surface temperature warming leads to the increase of potential intensity and enhances the possibility of TC poleward migration. Through controlling the TC formation in the eastern WNP tropics, the variations of vertical wind shear and horizontal winds affect TC Lysis latitude, facilitate the TC development environment around East Asia offshore and island chain areas, and steer TCs poleward migration through the southerly wind anomalies in the area north of 308N. Regarding the cyclonic vorticity in the lower troposphere and the divergence in the upper troposphere, their influence on TC Lysis latitude is mainly by adjusting the numbers of TCs rather than directly interfering with the TC movement process. The present results indicate that the northern WNP coastal region will also become a TC-prone area in the future, which needs to be treated with caution. [ABSTRACT FROM AUTHOR]

The mid-latitudes of East Asia are characterized by the interaction between the Asian summer monsoon and the westerly winds. Understanding long-term climate change in the marginal regions of the Asian monsoon is critical for understanding the millennial-scale interactions between the Asian monsoon and the westerly winds. Abrupt climate events are always associated with changes in large-scale circulation patterns; therefore, investigations into abrupt climate changes provide clues for responses of circulation patterns to extreme climate events. In this paper, we examined the time scale and mid-Holocene climatic background of an abrupt dry mid-Holocene event in the Shiyang River drainage basin in the northwest margin of the Asian monsoon. Mid-Holocene lacustrine records were collected from the middle reaches and the terminal lake of the basin. Using radiocarbon and OSL ages, a centennial-scale drought event, which is characterized by a sand layer in lacustrine sediments both from the middle and lower reaches of the basin, was absolutely dated between 8.0–7.0 cal kyr BP. Grain size data suggest an abrupt decline in lake level and a dry environment in the middle reaches of the basin during the dry interval. Previous studies have shown mid-Holocene drought events in other places of monsoon marginal zones; however, their chronologies are not strong enough to study the mechanism. According to the absolutely dated records, we proposed a new hypothesis that the mid-Holocene dry interval can be related to the weakening Asian summer monsoon and the relatively arid environment in arid Central Asia. Furthermore, abrupt dry climatic events are directly linked to the basin-wide effective moisture change in semi-arid and arid regions. Effective moisture is affected by basin-wide precipitation, evapotranspiration, lake surface evaporation and other geographical settings. As a result, the time scales of the dry interval could vary according to locations due to different geographical features. [ABSTRACT FROM AUTHOR]

Climate in Eastern Asia is composed of monsoon climate in the east, arid and semi-arid climate in the north and west, and the cold and dry climate of Qinghai-Tibetan Plateau in the southwest. The underlying causes for the evolution of East Asian climate during late Cenozoic have long been investigated and debated, particularly with regards to the role played by the Qinghai-Tibetan Plateau uplift and the global cooling. In this paper, we reviewed major research developments in this area, and summarized the important results. Based on a synthesis of data, we propose that the Qinghai-Tibetan Plateau uplift alone cannot fully explain the formation of monsoon and arid climates in Eastern Asia during the past 22-25 Ma. Other factors such as the global ice volume and high-latitude temperature changes have also played a vital role. Moreover, atmospheric CO changes may have modulated the monsoon and dry climate changes by affecting the location of the inter-tropical convergence zone (ITCZ), which controls the monsoon precipitation zone and the track of the East Asian winter monsoon during late Cenozoic. The integration of high-resolution geological record and numerical paleoclimate modeling could make new contributions to understanding the climate evolution and variation in eastern Asia in future studies. It could facilitate the investigation of the regional differences in East Asian environmental changes and the asynchronous nature between the uplift of Qinghai-Tibetan Plateau and their climatic effects. These would be the keys to understanding underlying driving forces for the evolution of the East Asian climate. [ABSTRACT FROM AUTHOR]

Using the NCEP/NCAR and JRA-25 monthly analysis data from 1979 to 2011, this paper analyzes the interdecadal variations of winter (Dec.–Feb.) mean surface air temperature (SAT) over East Asia by means of the empirical orthogonal function (EOF) analysis method. Two dominant modes were extracted, with the leading mode basically depicting a sign consistent SAT variation and the second mode describing a meridional dipole structure between the northern and southern parts of East Asia. These two modes can explain more than 60% of the variance. The leading mode is closely related to the intensity of Siberian high and the East Asian winter monsoon. The second mode exhibits a notable interdecadal shift in the late 1990s, with a turning point around 1996/1997. Winter SAT in the northern (southern) part of East Asia tends to be cooler (warmer) since the late 1990. Winter sea level pressure (SLP) differences between 1997–2011 and 1979–1996 show negative (positive) anomalies over southern (northern) Eurasia. At 500-hPa, an anomalous blocking high occurs over northern Eurasia, while a cyclone anomaly appears over northern East Asia. In addition, the upper-level East Asian jet stream tends to shift northward and become stronger after the late 1990. Indeed, the interdecadal shift of winter SAT over East Asia is dynamical consistent with changes of the large-scale atmospheric circulation in the late 1990s. The result indicates that previous autumn sea surface temperature (SST) in the North Atlantic Ocean, the Northern Indian Ocean and the western North Pacific Ocean, as well as sea ice concentration (SIC) in the northern Eurasia marginal seas and the Beaufort Sea also experienced obvious changes in the late 1990s. In particular, the interdecadal shifts of both SST in the North Atlantic Ocean and SIC in the Arctic Ocean and its marginal seas are well coherent with that of the winter SAT over East Asia. The results indicate that the interdecadal shift of East Asian winter SAT may be related to changes in the North Atlantic SST and the Arctic SIC in the late 1990s. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage (MIS) 13, an interglacial about 500,000 years ago, is unique due to an exceptionally strong East Asia summer monsoon (EASM) occurring in a relatively cool climate with low greenhouse gas concentrations (GHG). This paper attempts to find one of the possible mechanisms for this seeming paradox. Simulations with an Earth System model LOVECLIM show that the presence of ice sheets over North America and Eurasia during MIS-13 induces a positive phase of the winter North Atlantic Oscillation (NAO) like feature. The ocean having a longer memory than the atmosphere, the oceanic anomalies associated with NAO persists until summer. The signals of summer NAO are transmitted to East Asia to reinforce the monsoon there through the stationary waves excited at the Asian Jet entrance. The geopotential height shows clearly a mid-latitude wave train with positive anomalies over the eastern Mediterranean/Caspian Sea and the Okhotsk Sea and a negative anomaly over Lake Baikal. This reinforces the effect of the high-latitude wave train induced independently by the Eurasian ice sheet topography as shown in previous study. These features reinforce the Meiyu front and enhance the precipitation over East Asia. The results obtained from LOVECLIM are further confirmed by an atmospheric general circulation model, ARPEGE. [ABSTRACT FROM AUTHOR]

The aeolian deposits in the coastal region of North China are important for reconstructing paleoclimate. In this paper, chronology, climatic proxies and chemical compositions of four loess sections were studied. Optically stimulated luminescence (OSL) dating results indicate that the coastal loess was accumulated during late Quaternary, with ages ranging from the penultimate glacial period to the latest Holocene. Both granulometric characteristics and geochemical properties indicate that the dust provenance of the coastal loess is partially different from that of the Chinese Loess Plateau, characterized by more proximal contributions. Except distal dust transported by northwesterly winter winds from the inland gobi and sand deserts, the coastal loess also contains proximal, local coarse particles, which were derived from the exposed shelf as well as neighboring hills. Multiple climatic proxies, including color, magnetic susceptibility and particle size parameters, correlate well with the marine SPECMAP δ18O record, indicating that climatic changes in the coastal region of North China during the late Quaternary was mainly controlled by variations of the East Asian monsoon, driven by changes in global ice volumes. • Luminescence dating of coastal loess in eastern North China. • Coastal loess contain both distal and proximal source materials. • Exposed shelf during glacial time serving as an important source for coastal loess. • Costal loess reflects orbital climatic fluctuations driven by East Asian monsoon. [ABSTRACT FROM AUTHOR]

In the context of remarkable economic growth and financial development in the emerging economies of East Asia, this paper attempts to shed light on the ecological consequences (CO2 emission) of economic growth, foreign direct investment and financial development in the selected ASEAN-5 economies. Drawing on the data from 1982 to 2014, we employed a set of quantitative techniques for panel data analysis which entailed Dynamic Ordinary Least Squares (DOLS) and Fully Modified OLS (FMOLS) approaches. Our findings indicate that financial and economic development, as well as FDI, have a statistically significant long-run co-integrating relationship with environmental degradation (CO2 emissions) in the under analysis economies. It showed that in ASEAN-5 countries, economic growth, financial development and FDI leads to an increase in environmental degradation. The quadratic term for economic growth showed a negative impact on environmental degradation i.e. Environmental Kuznets Curve (EKC). Our key findings manifest and emphasise the importance of appropriate policies for more inclusive economic and financial development and sustainable foreign direct investment which does not impede on the environment. Image 1 • Remarkable economic growth, financial development and FDI Influx weighs on the environmental quality in ASEAN. • Financial and economic development and FDI have a significant long-run relationship with environmental degradation. • Weak evidence of Environmental Kuznets Curve (EKC). • FDI leads to environmental degradation in ASEAN i.e. support for Pollution Heavens Hypothesis (PHH) in ASEAN. • Different aspect of financial development has varying impact on the Environmental degradation. [ABSTRACT FROM AUTHOR]

Vegetation–climate relationships are often different at varying spatial scales, which is seldom taken into account in reconstructing past climate changes from fossil pollen spectra represent more local vegetation composition but using regional or extra-regional modern pollen–climate calibration set. In this paper, we employ 2620 surface pollen spectra and six pollen sequences from continental East Asia to reconstruct Holocene climate with modern analogue technique. A novel data set of vegetation sensitivity index (VSI) is introduced to examine vegetation–climate relationships in 0.5° search windows around the fossil sites (local) and in the tailored calibration sets (regional). Then, we compare them to the explanatory abilities of (reconstructed) climate variables on explaining the pollen variance in calibration sets and in the fossil pollen data sets using constrained ordination, cross-validation and significance test. By this procedure that we called local–regional–fossil comparison, we can better determine which variable reconstruction is valid and useful. In our cases, moisture variable reconstructions in temperate forest-steppe ecotone at the East Asian summer monsoon margin are reliable. Consistent Holocene moisture variations with a strong monsoon influence during 8.6–4.0 cal ka BP which can help us to better interpret human adaptations along the Great Wall. However, quantitative climate reconstructions at some sites are less reliable due to highly heterogeneous vegetation sensitivities surrounding the site, particularly for areas with complicated topographical contexts. We stress that vegetation sensitivities at local and regional scales both need to be investigated before conducting quantitative climate reconstruction. [ABSTRACT FROM AUTHOR]

Since the mid-1980s, power sector liberalization has been embraced at different levels in the East Asian countries of China, Japan, South Korea and Taiwan. The dominant rationale underlying power liberalization has been a quest for efficiency improvements, to be achieved by substituting private market activity for public regulations and by opening a country's electricity system to the global economy and management techniques. However, as the power system is increasingly liberalized, the possibility of establishing a local energy system, which has the great potential to restore sustainable environment-society relations, has been diminished. As an alternative to the power liberalization strategy, this paper proposes a restoration of local energy regimes based on the model of an energy commons and a decentralization paradigm. The innovative energy-policy model of the Sustainable Energy Utility, as applied in the case of Seoul, Korea, is explored as a possible option for a local energy strategy for East Asian countries. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the role that horizontal resolution plays in the simulation of East Asia precipitation. Two sets of numerical experiments are performed using the Regional Climate Model (RegCM2) nested in one-way mode within the CSIRO global coupled atmosphere-ocean model. In the first set we use the actual RegCM2 topography at the selected model resolutions, which are 45, 60, 90, 120, 180, 240 and 360 km. In the second set of the experiments, the same coarse CSIRO model topography is used in all simulations using the different resolutions of the first set. The results demonstrate that the simulation of East Asian precipitation improves as the horizontal resolution is increased. Moreover, it is shown that the simulations using a higher resolution along with the coarse CSIRO topography perform better than the simulations using a coarser model resolution with corresponding model topography. This suggests that over East Asia adequate spatial resolution to resolve the physical and dynamical processes is more important than topography. Lastly, the results indicate that model resolutions of 60 km or higher are needed to accurately simulate the distribution of precipitation over China and East Asia. [ABSTRACT FROM AUTHOR]

The present study examines variations in summertime (July–September) tropical cyclone (TC) activity over East Asia during the period 1951–2003. To represent TC activity, a total of 853 TC best tracks for the period were converted to TC passage frequencies (TPFs) within 5° × 5° latitude–longitude grids; TPFs are defined as the percentage values obtained by dividing the number of TC appearances in each grid box by the total number of TCs each year. Empirical orthogonal function analysis of the TPF showed three leading modes: two tropical modes that represent the long-term trend and the relationship with ENSO and one midlatitude mode that oscillates between south of Korea and southeast of Japan with an interannual time scale. The latter proved to be the most remarkable climatic fluctuation of summertime TC activity in the midlatitudes and is referred to as the East Asian dipole pattern (EADP) in this paper. Anomalous atmospheric flows directly connected to the EADP are an enhanced anticyclonic (cyclonic) circulation centering around Japan when the TPF is high south of Korea (southeast of Japan), thereby showing an equivalent barotropic structure in the entire troposphere. This regional circulation anomaly varies in conjunction with the zonally oriented quasi-stationary Rossby wave train in the upper troposphere. This wave train is meridionally trapped in the vicinity of the summer-mean jet stream; therefore, the mean jet stream alters its internal meandering structure according to the phase of the wave train. [ABSTRACT FROM AUTHOR]