Showing papers on "Far East published in 2008"

Tibetan Plateau warming and precipitation changes in East Asia

Abstract: [1] Observational evidence presented here indicates that the surface temperatures on the Tibetan Plateau (TP) have increased by about 1.8°C over the past 50 years. The precipitation pattern that is projected as a result of this warming resembles the leading pattern of precipitation variations in East Asia (EA). Numerical experiments with atmospheric general circulation models show that atmospheric heating induced by the rising TP temperatures can enhance East Asian subtropical frontal rainfall. The mechanism of the linkage is found to be through two distinct Rossby wave trains and the isentropic uplift to the east of the TP, which deform the western Pacific Subtropical High and enhance moisture convergence toward the EA subtropical front. The model calculations suggest that the past changes in TP temperatures and EA summer rainfall may be linked, and that projected future increases in TP temperatures may lead to further enhanced summer frontal rainfall in EA region.

Reduction of future monsoon precipitation over China: comparison between a high resolution RCM simulation and the driving GCM

Abstract: Multi-decadal high resolution climate change simulations over East Asia are performed using the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model, RegCM3, nested within the NASA/NCAR global model FvGCM. Two sets of simulations are conducted at 20-km grid spacing for present day and future climate (IPCC A2 scenario). The mean precipitation change during the monsoon season (May to September) over China is analyzed and intercompared between the RegCM and FvGCM. Simulation of the present day precipitation by the RegCM shows a better performance than that of the driving FvGCM in terms of both spatial pattern and amount. The main improvement of the RegCM is the removal of an artificial precipitation center over the eastern edge of the Tibetan Plateau simulated by the FvGCM. The FvGCM simulates a predominant increase of precipitation over the region, whereas the RegCM shows extended areas of decrease. The causes of these differences are investigated and explained in terms of the different topographical forcing on circulation and moisture flux in the two models. We also find that the RegCM-simulated changes are in better agreement with observed precipitation trends over East Asia. It is suggested that high resolution models are needed to better investigate future climate projections over China and East Asia.

The paleolithic settlement of Asia

Abstract: This book provides the first analysis and synthesis of the evidence of the earliest inhabitants of Asia before the appearance of modern humans 100,000 years ago. Asia has received far less attention than Africa and Europe in the search for human origins, but is no longer considered of marginal importance. Indeed, a global understanding of human origins cannot be properly understood without a detailed consideration of the largest continent. In this study, Robin Dennell examines a variety of sources, including the archaeological evidence, the fossil hominin record, and the environmental and climatic background from Southwest, Central, South, and Southeast Asia, as well as China. He presents an authoritative and comprehensive framework for investigations of Asia's oldest societies, challenges many long-standing assumptions about its earliest inhabitants, and places Asia centrally in the discussions of human evolution in the past two million years.

Y chromosome evidence of earliest modern human settlement in East Asia and multiple origins of Tibetan and Japanese populations

Abstract: The phylogeography of the Y chromosome in Asia previously suggested that modern humans of African origin initially settled in mainland southern East Asia, and about 25,000–30,000 years ago, migrated northward, spreading throughout East Asia. However, the fragmented distribution of one East Asian specific Y chromosome lineage (D-M174), which is found at high frequencies only in Tibet, Japan and the Andaman Islands, is inconsistent with this scenario. In this study, we collected more than 5,000 male samples from 73 East Asian populations and reconstructed the phylogeography of the D-M174 lineage. Our results suggest that D-M174 represents an extremely ancient lineage of modern humans in East Asia, and a deep divergence was observed between northern and southern populations. We proposed that D-M174 has a southern origin and its northward expansion occurred about 60,000 years ago, predating the northward migration of other major East Asian lineages. The Neolithic expansion of Han culture and the last glacial maximum are likely the key factors leading to the current relic distribution of D-M174 in East Asia. The Tibetan and Japanese populations are the admixture of two ancient populations represented by two major East Asian specific Y chromosome lineages, the O and D haplogroups.

Securing Japan: Tokyo's Grand Strategy and the Future of East Asia

Abstract: For the past sixty years, the U.S. government has assumed that Japan's security policies would reinforce American interests in Asia. The political and military profile of Asia is changing rapidly, however. Korea's nuclear program, China's rise, and the relative decline of U.S. power have commanded strategic review in Tokyo just as these matters have in Washington. What is the next step for Japan's security policy? Will confluence with U.S. interests-and the alliance-survive intact? Will the policy be transformed? Or will Japan become more autonomous? Richard J. Samuels demonstrates that over the last decade, a revisionist group of Japanese policymakers has consolidated power. The Koizumi government of the early 2000s took bold steps to position Japan's military to play a global security role. It left its successor, the Abe government, to further define and legitimate Japan's new grand strategy, a project well under way-and vigorously contested both at home and in the region. Securing Japan begins by tracing the history of Japan's grand strategy-from the Meiji rulers, who recognized the intimate connection between economic success and military advance, to the Konoye consensus that led to Japan's defeat in World War II and the postwar compact with the United States. Samuels shows how the ideological connections across these wars and agreements help explain today's debate. He then explores Japan's recent strategic choices, arguing that Japan will ultimately strike a balance between national strength and national autonomy, a position that will allow it to exist securely without being either too dependent on the United States or too vulnerable to threats from China. Samuels's insights into Japanese history, society, and politics have been honed over a distinguished career and enriched by interviews with policymakers and original archival research. Securing Japan is a definitive assessment of Japanese security policy and its implications for the future of East Asia.

Spatial and temporal variations of the Kuroshio east of Taiwan, 1982–2005: A numerical study

Abstract: [1] A 1/8° East Asian Marginal Seas model nested to a larger-domain North Pacific Ocean model is implemented over a span of 24 years from 1982 to 2005 to investigate the spatial and temporal variations of the Kuroshio east of Taiwan. Between 22 and 25°N, the mean state and variability of the Kuroshio, such as the two paths observed in the trajectories of surface drifters southeast of Taiwan and the branching of the Kuroshio northeast of Taiwan, are well reproduced by the model. Southeast of Taiwan, the Kuroshio is mostly in the top 300 m in the inshore path but extends to 600 m in the offshore path. Northeast of Taiwan, the Kuroshio follows the shelf edge in the East China Sea but may branch along a path south of the Ryukyu Islands. The latter path often meanders southward, and a significant portion of the Kuroshio transport may be diverted to this path. The Kuroshio extends from the coast to 123–123.5°E between 22 and 25°N with currents reaching a depth of 1000 m at some latitudes. The Kuroshio transports averaged over five sections east of Taiwan are 28.4 ± 5.0 Sv and 32.7 ± 4.4 Sv with and without the contribution from the countercurrent, respectively.

Regional summer precipitation events in Asia and their changes in the past decades

Abstract: [1] A recently derived data set of daily precipitation is used to study the summer precipitation events over Asia and their changes in the decades of 1978–2002. Regional features of the precipitation over entire tropical-subtropical Asia are investigated, exploiting the increased resolution and improved accuracy of the data set relative to other estimates. The changes in precipitation amount and precipitation days for total, extreme, heavy, and light-moderate precipitations are examined. Although the Asian summer monsoon precipitation falls mostly in the form of light-moderate rainfalls, regions of relatively frequent extreme precipitation events are found over South Asia and East-Southeast Asia. These regions are separated by a narrow zone over the Indo-China peninsula, along 100°E, where extreme precipitation rarely occurs. During the period examined, the amount of total precipitation and light-moderate precipitation exhibits positive trends over southeastern and northwestern China, separated by negative trends over central China and southwestern and northeastern Asia. This sandwich-like pattern, which also appears in the fields of precipitation days and soil moisture content, is associated with the enhanced water vapor supply related to the strengthened monsoon flow over southeastern China and the anomalous easterlies over northwestern China. It is also associated with the decreased water vapor supply linked to the weakened monsoon flows over southern-southwestern Asia and central China and to the anomalous northerly flow over northeastern Asia. Over the entire tropical-subtropical Asia, the largest changes in precipitation, atmospheric circulation, and water vapor transport occur over southern China. On the other hand, the changes over India are much smaller.

Reshaping Economic Geography in East Asia

Abstract: Reshaping economic geography in East Asia illustrates how extensively spatial factors have influenced and informed by growth and development in the region. This study was conceived as a companion volume to and informed by the World Development Report (WDR) 2009: reshaping economic geography. By providing case studies and illustrative examples and by deepening the understanding of the forces of economic geography in the East Asia region, this work helped to substantiate some of the key concepts in the WDR 2009. There is full consistency in terms of the analytical framework used and broad agreement on how economic geography has influenced growth trends across a diverse range of countries. Reshaping economic geography in East Asia also highlights the dramatic urbanization process under way in the region, evidenced by the number of globally recognized 'mega cities'. Seven of the world's 21 mega cities are in East Asia. Cities in East Asia generate about three-quarters of annual output and between a half and two-thirds of exports. Often, much of this is concentrated in one major city: Bangkok. Bangkok accounts for 40 percent of Thailand's gross domestic product (GDP) and Manila for 30 percent. Other major centers such as Guangzhou, Jakarta, Seoul, Shanghai, and Tokyo are seen as driving their economies. East Asian cities have been able to deliver the agglomeration benefits required for growth and are now exceptionally well connected to the global economy. The region, excluding Japan, is home to 16 of the largest 25 seaports in the world and 14 of the largest 25 container ports. Without this improved connectivity, the region's rapid expansion in trade volumes will not have been possible. This collection of studies is organized in four sections. The first section comprises chapters dealing with the 'context and concepts' for this volume. The second deals with Southeast Asia, specifically, the Association of South East Asian Nations (ASEAN) countries. The third deals with Northeast Asia: China and the Republic of Korea, and the fourth section provide an overview of lessons learned. The time perspective for most of the studies spans several decades; in many cases, outcomes and policies can be traced back half a century or more.

Siberia at the Last Glacial Maximum: Environment and Archaeology

Abstract: This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene, called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia, based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored clothes, and megafaunal bones as fuel.

Rainwater chemistry at a high-altitude station, Mt. Lulin, Taiwan: Comparison with a background station, Mt. Fuji

Abstract: was 5.12, approaching that of typical natural water. Non-sea-salt (nss) SO4 and NH4 were the most abundant anion and cation, respectively, both existing mostly in the form of (NH4)2SO4. Chloride was excessive in most of the samples. The signature of biomass burning in south and Southeast Asia was evident in the Mt. Lulin samples. Concentrations of chemical species were found to be elevated in the spring months, owing to the emissions from south/Southeast Asia and peak biomass burning activities and frequent dust storms (in the Indian Thar Desert). In the summer and fall seasons our samples are mainly influenced by marine air masses. The episodic species concentrations measured at the summit of Mt. Fuji during the spring were due to the influence of volcanic emissions from Miyake-Jima. Tropical cyclones (TC) over the western Pacific region and deep convections play important roles in the transport of boundary layer pollutants to the free troposphere, although their influence is not frequently detected at Mt. Lulin and Mt. Fuji. The rainwater chemistry at Mt. Lulin and Mt. Fuji were examined together with the aerosol chemistry obtained from the TRACE-P and ACE-Asia campaigns. The analysis of the Mt. Lulin data set demonstrates its background characteristics of the rainwater chemistry in east Asia.

Winter-to-Spring Transition in East Asia: A Planetary-Scale Perspective of the South China Spring Rain Onset

Abstract: Analysis of observations from 1979 to 2002 shows that the seasonal transition from winter to spring in East Asia is marked with a distinctive event—the onset of the south China spring rain (SCSR). In late February, the reduced thermal contrast between ocean and land leads to weakening of the Asian winter monsoon as well as the Siberian high and the Aleutian low. Meanwhile, convection over Australia and the western Pacific Maritime Continent is suppressed on the passage of the dry phase of a Madden–Julian oscillation (MJO). In conjunction with the seasonal march of monsoon circulation in the Indonesian– Australian sector, this MJO passage weakens the local thermally direct cell in the East Asia–Australia sector. This development is further accompanied by a series of adjustments in both the tropics and midlatitudes. These changes include attenuation of the planetary stationary wave, considerable weakening of the westerly jet stream over much of the central Pacific adjacent to Japan, and reduction of baroclinicity near the East Asian trough. The influence of concurrent local processes in midlatitudes on the SCSR onset is also important. The weakened jet stream is associated with confinement of frontal activities to the coastal regions of East Asia as well as with rapid expansion of the subtropical Pacific high from the eastern Pacific to the western Pacific. A parallel analysis using output from an experiment with a GFDL-coupled GCM shows that the above sequence of circulation changes is well simulated in that model.

Simulation of direct effects of black carbon aerosol on temperature and hydrological cycle in Asia by a Regional Climate Model

Abstract: The simulation of direct radiative effect of black carbon (BC) aerosol over Asia is carried out with application of Regional Climate Model RegCM3 over the period of 1993–2003 based on BC emission inventory in 2000. Major findings are as follows. The column burden of BC exceeds 1 mg/m2 in central, eastern, and southern China with the highest value of 2.5 mg/m2 over Sichuan Basin of China, and is of 1–2 mg/m2 in India subcontinent. The column averaged advection field of BC shows an eastward tendency in north of 20° N, whereas an opposite trend is found in south of 10° N. Off-line radiative forcing (RF) induced by BC, which is due to direct absorption or scattering of BC, is positive at the top of the atmosphere (TOA), while maximum effect is found over Sichuan Basin. The RF is of 1–1.5 W/m2 in areas such as the middle and low reaches of the Yangtze River, East China Sea, South China Sea, Indo-China Peninsula and most parts of Indian subcontinent. Surface RF is found to be negative and its absolute value is larger than that at TOA. Based on simulation results, BC’s impacts on temperature, stratification stability, water vapor, precipitation and evaporation etc., are primarily characterized by cold-and-wet change in southern and northwest China, cold-and-dry change in northern and northeast China, warm-and-wet change of India subcontinent, as well as warm-and-dry change of Central Asia.

East Asian multilateralism : prospects for regional stability

Abstract: While the Iraq war and Middle East conflicts command the attention of the United States and most of the rest of the developed world, fundamental changes are occurring in East Asia. North Korea has tested nuclear weapons, even as it and South Korea have effectively entered a period of tepid detente; relations among China, Japan, and South Korea are a complex mixture of conflict and cooperation; and Japan is developing more forthright security policies, even as it deepens ties with the United States. Together, these developments pose vital questions for world stability and security. In East Asian Multilateralism, prominent international foreign affairs scholars examine the range of implications of shifting alignments in East Asia. The first part delves into the intraregional dynamics, and the second assesses current economic conditions and policies within individual East Asian states. The third section examines the challenge of regional cooperation from the perspectives of local players, while the fourth analyzes the implications for foreign policy in the United States and in Asia. This thorough review and assessment charts the preconditions and prospects for deeper multilateralism, poses tough questions about America's security and national interests in the region, and carries a plea for more serious institution-building in the North Pacific, using the ongoing six-party process in talks on North Korea as a point of departure.

Development of a statistical downscaling model for projecting monthly rainfall over East Asia from a general circulation model output

Abstract: [1] The objective of this paper is to describe a statistical downscaling model based on established links between large scale variables from a general circulation model (GCM) and regional rainfall to project climate change over East Asia in the 21st century. We develop a SVD (singular value decomposition)-based regression model to downscale the GCM data. In order to establish a link between monthly regional precipitation and large scale variable (mean sea level pressure, 10 m wind speed, or 2 m temperature), we used the IS92a scenario data of ECHAM4/OPCY3 and the data from the Climate Research Unit from 1901 to 1990. In the 20th century, their connections have remained unchanged over time for all seasons. The continuity of these relationships to the next century is tested by checking the similarity in the main SVD modes of predictors and the empirical orthogonal functions of predictors throughout the 20th and 21st century. Furthermore, comparing the SVD-downscaled and ECHAM4-projected changes of precipitation in the 2090s with respect to the 1990s reveals similar patterns over most areas with much more detailed regional characteristics, although the magnitude of change is not compatible. In all, the annual rainfall over East Asia is projected to increase over northern China and the Indochina peninsula and to decrease over the coast of southern China by the end of the 21st century.

Interdecadal variations of East Asian summer monsoon northward propagation and influences on summer precipitation over East China

Abstract: The interdecadal variation of northward propagation of the East Asian Summer Monsoon (EASM) and summer precipitation in East China have been investigated using daily surface rainfall from a dense rain gauge network in China for 1957–2001, National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis, European Center for Medium-Range Weather Forecast (ECMWF) reanalysis, and Global Mean Sea Level Pressure Dataset (GMSLP2) from Climatic Research Unit (CRU). Results in general show a consistent agreement on the interdecadal variability of EASM northward propagations. However, it appears that the interdecadal variation is stronger in NCEP than in ECMWF and CRU datasets. A newly defined normalized precipitation index (NPI), a 5-day running mean rainfall normalized with its standard deviation, clearly depicts the characteristics of summer rainbelt activities in East China in terms of jumps and durations during its northward propagations. The EASM northward propagation shows a prominent interdecadal variation. EASM before late 1970s had a rapid northward advance and a northern edge beyond its normal position. As a result, more summer rainfall occurred for the North China rainy season, Huaihe-River Mei-Yu, and South China Mei-Yu. In contrast, EASM after late 1970s had a slow northward movement and a northern edge located south of its normal position. Less summer precipitation occurred in East China except in Yangtze River basin. The EASM northernmost position (ENP), northernmost intensity (ENI), and EASM have a complex and good relationship at interdecadal timescales. They have significant influences on interdecadal variation of the large-scale precipitation anomalies in East China.

Human security in East Asia

Abstract: agenda in East Asia. It offers us a cutting-edge assessment of the conceptual debates and empirical cases that the region has experienced so far. On that basis, it provides us with a balanced and realistic framework that we need in overcoming the ongoing challenge we face: achieving policy collaboration among various stakeholders interested or involved in human security activities. This is a must read for academics and practitioners alike.” Dr. Tsuyoshi Kawasaki, Assistant Professor Department of Political Science, Simon Fraser University, Vancouver, Canada