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With the most prominent topography on Earth, the Tibetan Plateau has profound influences on the hydrologic cycle and climate dynamics in Asia. However, the regional uplift history of the Tibetan Plateau remains highly debated. Here, we use europium anomalies and LREE/HREE ratio in detrital zircon, combined with whole-rock La/Yb N ratio, to constrain the crustal thickness and topographic evolution of the Gangdese mountains in southern Tibet. Europium anomaly, controlled by pressure-sensitive minerals plagioclase and garnet, has been shown to correlate with crustal thickness. Our results reveal contrasting crustal thickening histories of the eastern (east of ∼88°E) and western (west of ∼88°E) parts of the Gangdese. Prior to the India-Eurasia collision (∼60–55 Ma), the crust of the eastern Gangdese thickened continuously from ∼40 km to nearly 60 km, while the western Gangdese maintained a mildly thickened crust of ∼50 km. Both parts underwent substantial thinning (to 40–45 km) immediately before the India-Eurasia collision, but the eastern Gangdese re-thickened rapidly afterwards. In the western Gangdese, post-collisional thickening was delayed until ∼40–20 Ma, which resulted in a mild elevation of ∼2000 m for most areas of southern Tibet until the late Oligocene. This diachronous uplift of the Gangdese after collision may have resulted from more mantle-derived magma additions in the eastern Gangdese before collision, which could rheologically weaken its lithosphere. We suggest that the diachronous uplift of the Gangdese after the India-Eurasia collision may have dominated the moisture transfer pattern across southern Tibet through the late Eocene and intensified the South Asian monsoon through the Oligocene-Miocene boundary (∼25–20 Ma). • Eastern and western Gangdese show different crustal thickening histories. • Uplift of western Gangdese was delayed by at least 20 Myr after collision. • Diachronous uplift of Gangdese might impact the regional and South Asian climate. [ABSTRACT FROM AUTHOR]

The distribution pattern of arid–humid climate in the modern northwest–southeast confrontation in Asia evolved from the zonal distribution pattern of the Paleogene. However, this evolutionary process remains poorly constrained by geological evidence. In this paper, we analyze the characteristics of sporopollen assemblages recorded in Late Eocene strata of the Jianchuan Basin in southwest China. We show that vegetation patterns exhibited a remarkable shift from tropical–subtropical sparse forest to subtropical–temperate mixed broad-leaved–coniferous forest at ∼40.6 Ma; this shift is further indicated by the rapid decrease in drought-tolerant plants, mostly Ephedra and Chenopodiaceae, evidence that the previous hot–dry climate was replaced by a warm–humid climate at this time. This evidence suggests that the Asian monsoon began to affect the study area at ∼40.6 Ma. We then comprehensively integrated sporopollen results from several basins across East Asia, revealing that the frontal edge of the humid monsoon climate moved intermittently to the northwest after the Late Eocene, and may have advanced to the Lunpola–Lanzhou line by the early Late Oligocene, this being similar to the position of the leading edge of the modern monsoon. Moreover, the frontal edge of the humid monsoon climate may have extended as far as the Qaidam Basin during the Middle Miocene, but then gradually retreated to the position of the modern monsoon front. The uplift of the Tibetan Plateau and global climate change may have played dominant roles in this evolution. • A Late Eocene sporopollen record was obtained from the subtropical Yunnan region. • The Asian monsoon extended from tropical to subtropical regions around 40.6 Ma. • The Asian monsoon reached the modern monsoon front in the early Late Oligocene. • The Asian monsoon advanced on one occasion to the Qaidam Basin in the Mid-Miocene. [ABSTRACT FROM AUTHOR]

Uplift of the Gangdese Mountains is important to the evolution of Asian monsoons and the formation of Tibetan Plateau, but its paleoaltitude before the India-Asia collision (Late Cretaceous) is less constrained so far. In this study, we investigate whether the geological records, which are indicators of soil dryness, discovered in East Asia can provide such a constraint. Through climate modeling using the Community Earth System Model version 1.2.2, it is found that the extent of dry land in East Asia is sensitive to the altitude of the Gangdese Mountains. It expands eastwards and southwards with the rise of the mountain range. Comparison of the model results with all the available geological records in this region suggests that the Gangdese Mountains had attained a height of ∼2 km in the Late Cretaceous.

The East Asian coastal mountains have been in place during the Late Cretaceous times, thus substantially influencing the Asian climate. So far, their altitude is uncertain. Here we investigate the influence of such mountains on Asian climate using an atmosphere‐ocean general circulation model, Community Earth System Model version 1.2.2. Simulation results show that extensive deserts would develop over the eastern part of the East Asia if the altitude of the coastal mountains was greater than 2 km. This is due to the pumping effect of the coastal mountains which deprives the moisture from the East Asian interior during summer and autumn, leading to less precipitation and greater potential evapotranspiration. The existence of extensive desert areas would be more consistent with the presented Asian paleoenvironmental reconstructions. Therefore, our results independently indicate that the altitude of the coastal mountains had attained 2 km or more by the early Late Cretaceous. Key Points: The East Asian coastal mountains had risen to 2 km or higher during the early Late CretaceousThe East Asian coastal mountains had a drying effect on the Asian climate during the Late CretaceousThe East Asian coastal mountains decreased the Asian precipitation by means of their pumping effect [ABSTRACT FROM AUTHOR]

The growth of the Tibetan Plateau (TP) is one of the important forcings acting on the evolution of the Asian climate during the Cenozoic. However, whether vegetation and ocean feedbacks play a specific role in the Asian climate response to TP uplift remains unclear. Here we investigate this issue through a set of numerical experiments with the Community Earth System Model. The results indicate that vegetation and ocean feedbacks have important but different effects on the Asian climate change in association with TP uplift, which are intrinsically related to the adjustment of thermal structure. The vegetation feedback leads to excess annual precipitation in East China and South Asia and a weakening of the Asian winter monsoon winds and winter middle‐ and high‐level tropospheric westerly winds from South Asia to the northwestern Pacific. By comparison, the ocean feedback induces a deficit of annual precipitation particularly in most areas of the Bay of Bengal, Malay Peninsula, and the South China Sea, a weakening of the Asian summer and winter monsoon winds, and a strengthening of the winter middle‐ and high‐level tropospheric westerly winds from South Asia to the northwestern Pacific. These results highlight the importance of vegetation and ocean feedbacks and further facilitate a better understanding of the paleoclimatic response to the uplift of the TP. Key Points: Vegetation and ocean feedbacks have a remarkable effect on the response of the Asian climate to TP upliftThese feedbacks have different effects on precipitation, monsoon winds, and middle‐ and high‐level tropospheric westerly windsThe different effects of vegetation and ocean feedbacks are related to the thermal structure alteration [ABSTRACT FROM AUTHOR]

Known as the "water tower of central Asia" and a crucial component of the Tibetan Plateau (TP), the Pamir–Tienshan snow cover (PTSC) exerts profound impacts on regional and global climate extremes during summer. However, researches on origins of the summer PTSC variability have not attracted adequate attention. In recent works, the spring North Atlantic Oscillation (NAO) has been shown to "prolong" its influence through the North Atlantic tri‐pole sea surface temperature anomalies (Tri‐SSTAs) and affect remote Asian climate in the subsequent summer. The present study discovers that the spring NAO has a significant positive correlation with the summer PTSC in the period 1967–1981, but such connection weakens after 1981. The North Atlantic Tri‐SSTAs induced by the spring NAO during these two epochs can both persist into ensuing summer but excite significantly different downstream atmospheric teleconnections. The Rossby wave train triggered by positive (or negative) Tri‐SSTAs during the 1967–1981 period exhibits an anomalous cyclonic (or anticyclonic) centre over the Pamir–Tienshan region, favouring an excessive (or reduced) PTSC. By contrast, such atmospheric anomaly centre is not evident during the 1982–2014 period. Numerical experiments suggest that westwards shift of the spring NAO northern centre can modulate the Tri‐SSTA pattern via the wind–evaporation–SST feedback, which could further result in the displacement of the atmospheric anomaly centres in the Rossby wave train in summer. Therefore, such change in the spring NAO itself is responsible for the inter‐decadal change of the spring NAO impact on the summer PTSC. (a) Altitude (colour shadings, m) of the Pamir–Tienshan (black box) and its adjacent areas. (b) Long‐term mean (contours, %) and standard deviations (colour shadings) of the Pamir–Tienshan (PT) snow cover (PTSC) during boreal summer in the period 1967–2014. The areas included by the black curves are 2,500 m a.s.l. (c) One‐point (39°N, 73°E) correlation maps of the summer snow cover. The summer PTSC anomalies averaged in the plot areas and passed 99% confidence level based on a Student's t test (colour shading areas) is defined as a PTSC index (PTSCI). [ABSTRACT FROM AUTHOR]

This study presents trends in a newly compiled temperature extreme indices dataset for Asia covering the period of 1958-2012. Daily data were homogenized prior to the calculation of the indices. A clear warming trend was observed in all indices, which is consistent with the global warming. In most of the indices, larger warming was observed at high latitudes than at low latitudes. We also compared observations with simulations from the Coupled Model Inter-comparison Project Phase 5 for some indices using an optimal fingerprinting method. These indices include the number of days with daily maximum or minimum temperatures greater than their 90th percentiles or smaller than their 10th percentiles, the annual highest daily maximum and minimum temperatures, and the annual lowest daily maximum and minimum temperatures. We determined that the warming trend was inconsistent with the natural variability of the climate system but agreed with climate responses to external forcing as simulated by the models. The anthropogenic and natural signals could be detected and separated from each other in the region for almost all indices, indicating the robustness of the warming signal as well as the attribution of warming to external causes. [ABSTRACT FROM AUTHOR]

This study uses 2001-2014 satellite observations and reanalyses to investigate the seasonal characteristics of Cloud Radiative Effects (CREs) and their associations with cloud fraction (CF) and precipitation over the Asian monsoon region (AMR) covering Eastern China (EC) and South Asia (SA). The CREs exhibit strong seasonal variations but show distinctly different relationships with CFs and precipitation over the two regions. For EC, the CREs is dominated by shortwave (SW) cooling, with an annual mean value of − 40 W m for net CRE, and peak in summer while the presence of extensive and opaque low-level clouds contributes to large Top-Of-Atmosphere (TOA) albedo (>0.5) in winter. For SA, a weak net CRE exists throughout the year due to in-phase compensation of SWCRE by longwave (LW) CRE associated with the frequent occurrence of high clouds. For the entire AMR, SWCRE strongly correlates with the dominant types of CFs, although the cloud vertical structure plays important role particularly in summer. The relationships between CREs and precipitation are stronger in SA than in EC, indicating the dominant effect of monsoon circulation in the former region. SWCRE over EC is only partly related to precipitation and shows distinctive regional variations. Further studies need to pay more attention to vertical distributions of cloud micro- and macro-physical properties, and associated precipitation systems over the AMR. [ABSTRACT FROM AUTHOR]

The Tianshan Mountains are known as the 'water tower' in the arid region of Central Asia. Change in precipitation amount and pattern can have a profound impact on regional civilization and life supporting ecosystems. For this study, a systematic analysis of long-term precipitation data for the eastern Tianshan Mountains was conducted to investigate the influence of climate teleconnections on annual and intra-annual precipitation using data collected between 1951 and 2014 from 39 meteorological stations. Annual precipitation has increased during the past six decades at an average rate of 6.7 mm/10 years largely due to the increase in precipitation during the intra-annual wet period (May-October). The annual precipitation and its rate of increase were higher in the northwestern region. Annual precipitation was found to be most strongly correlated with index of Indian Summer Monsoon (ISM), and partially correlated with indices of Pacific Decadal Oscillation (PDO), Pacific North American Teleconnection Pattern (PNA), Arctic Oscillation (AO), El Nino-Southern Oscillation (ENSO), and North Atlantic Oscillation (NAO). ISM was positively correlated with the precipitation in almost the entire region during the intra-annual wet period, while it showed positive correlations in the northern slope and the alpine region, and negative correlations in the southern slope during the intra-annual dry period (November to April). PDO had much weaker influence both in spatial scale and strength and primarily affected low elevations on the southern slopes of the middle and western regions. The impacts of PNA and AO on precipitation were weak and localized. ENSO and NAO indices were almost not correlated with annual precipitation observation in the eastern Tianshan Mountains. [ABSTRACT FROM AUTHOR]

The Upper Tropospheric Quasi-Biweekly Oscillation (UQBW) of the South Asian monsoon is studied using the potential vorticity field on the 370 K isentrope. The UQBW is shown to be a common occurrence in the upper troposphere during the monsoon, and its typical evolution is described. We suggest that the UQBW is a phenomenon of both the middle and tropical latitudes, owing its existence to the presence of the planetary-scale upper-tropospheric monsoon anticyclone. The UQBW is first identified as Rossby waves originating in the northern flank of the monsoon anticyclone. These Rossby waves break when reaching the Pacific Ocean, and their associated cyclonic PV anomalies move southward to the east of Asia and then westward across the Indian Ocean and Africa advected by the monsoon anticyclone. A strong correlation, or co-evolution, between the UQBW and quasi-biweekly oscillations in the lower troposphere (QBW) is also found. In particular, analysis of vertically-integrated horizontal moisture transport, 850 hPa geopotential, and outgoing long-wave radiation show that the UQBW is usually observed at the same time as, and co-evolves with, the lower tropospheric QBW over South Asia. We discuss the nature of the UQBW, and its possible physical link with the QBW. [ABSTRACT FROM AUTHOR]

Orbital forcing influences climate phenomena by changing incoming solar radiation in season and latitude. Here, changes in the El Niño-Southern Oscillation (ENSO)'s impact on the East Asian winter monsoon (EAWM) due to orbital forcing, especially for three selected time periods in each of two interglacial periods, the Eemian (126, 122, 115 ka) and Holocene (9, 6, 0 ka), are investigated. There was a high negative correlation between ENSO and EAWM when the obliquity was low, the processional angle was large, and especially when accompanied by large eccentricity, which corresponds to a weaker monsoon period. The correlation was also high when ENSO variability was high, which interestingly corresponded to lower obliquity and higher-degree precession periods. Therefore, as both lower obliquity and higher-degree precession, such as during 115 ka and 0 ka, cause the EAWM to be weakened through higher winter insolation over Northern hemisphere, and the ENSO to be enhanced through an intensified zonal contrast of the equatorial sea surface temperature, the relationship between the ENSO and EAWM becomes tighter. The opposite case (i.e., during 126 and 9 ka) is also true dynamically. Furthermore, the sensitivity of boreal winter precipitation against sea surface temperature (SST) anomaly over the tropical Pacific, which depends on mean SST, was positively correlated to the strength of the ENSO-EAWM correlation, implying that the warmer mean ocean surface causes the strong response of atmosphere to change in the SST anomaly, thereby enhancing the impact of ENSO on EAWM. Warmer wintertime tropical SST is attributed to higher insolation over the tropics, especially during 115 and 0 ka, while cooler SSTs occurred during 126 and 9 ka. [ABSTRACT FROM AUTHOR]

The present study investigates the fidelity and resolution sensitivity of Met Office Unified Model Global Atmosphere 3.0 in simulating the intraseasonal oscillation (ISO) of the East Asia and western North Pacific summer monsoon. Two sets of model simulations at horizontal resolutions of N216 (60 km) and N96 (130 km) forced by observed daily high-resolution sea-surface temperature are examined and compared with the observations. Diagnostic results show that the model can well reproduce the gross spatio-temporal features of observed summer ISO over East Asia and the western North Pacific in terms of period, dominant rotated empirical orthogonal function (REOF) mode, variance, northward propagation, cycle evolution and vertical structure. The intraseasonal change in intensity and position of the western North Pacific subtropical high and upper troposphere westerly jet associated with the northward propagating ISOs are also reasonably captured in the model. Moreover, increasing horizontal resolution improves most aspects of the ISO simulation, especially the intensity and northward propagation of the ISO-related convection and circulation systems. Further analysis indicates that the improvement as resolution increases is related to the weakening in background state of the East Asian summer monsoon, which is due to the realistic simulation of land-sea thermal contrast in the higher resolution model. This study suggests that enhanced model resolution can have some beneficial impacts on the ISO simulation. [ABSTRACT FROM AUTHOR]

A multiple parameter dating technique was used to establish a depth/age scale for a 171.3 m (145.87 m w.e.) surface to bedrock ice core (Bl2003) recovered from the cold recrystallization accumulation zone of the Western Belukha Plateau (4115 m a.s.l.) in the Siberian Altai Mountains. The ice-core record presented visible layering of annual accumulation and of δ18O/δD stable isotopes, and a clear tritium reference horizon. A steady-state glacier flow model for layer thinning was calibrated and applied to establish a depth/age scale. Four radiocarbon (14C) measurements of particulate organic carbon contained in ice-core samples revealed dates for the bottom part of Bl2003 from 9075 ± 1221 cal a BC at 145.2 ± 0.1 m w.e. (0.665 m w.e. from the bedrock) to 790 ± 93 AD at 121.1 m w.e. depth. Sulfate peaks coincident with volcanic eruptions, the Tunguska meteorite event, and the 1842 dust storm were used to verify dating. Analysis of the Bl2003 ice core reveals that the modern Altai glaciers were formed during the Younger Dryas (YD) (~10 950 to ~7500 cal a BC), and that they survived the Holocene Climate Optimum (HCO) (~6500 to ~3600 cal a BC) and the Medieval Warm Period (MWP) (~640 to ~1100 AD). A decrease in air temperature at the beginning and an abrupt increase at the end of the YD were identified. Intensification of winds and dust loading related to Asian desert expansion also characterized the YD. During the YD major ion concentrations increased significantly, up to 50 times for Na+ (background), up to 45 times for Ca2+ and Mg2+, and up to 20 times for SO42− relative to the recent warm period from 1993 to 2003. A warm period lasted for about three centuries following the YD signaling onset of the HCO. A significant and prolonged decrease in air temperature from ~2000 to ~600 cal a BC was associated with a severe centennial drought (SCD). A sharp increase in air temperatures after the SCD was coincident with the MWP. After the MWP a cooling was followed gradually with further onset of the Little Ice Age. During the modern warm period (1973–2003) an increase in air temperature is noted, which nearly reaches the average of HCO and MWP air temperature values. [ABSTRACT FROM AUTHOR]

The outputs of last millennium (A.D. 850–1850) experiments from seven climate models of the Paleoclimate Modeling Intercomparison Project 3, have been used to analyze decadal to centennial climatic variations over Asia, including the Indian monsoon, the East Asian monsoon and the westerly jet. In particular, the differences between the Medieval Warm Period (MWP, A.D. 901–1200) and the Little Ice Age (LIA, A.D. 1551–1850) are focused on. Statistically, significant temperature contrasts between the MWP and LIA are simulated by all of the models, and larger temperature deviations occur during colder periods. Although discrepancies exist, stronger Indian and East Asian summer monsoon circulations, as well as a stronger Asian westerly jet stream in winter, are found during the MWP compared to the LIA, in most of the models. These changes primarily originate from different atmospheric thermal structures over the two periods, which occur in response to the external radiative forcings. However, the monsoon-associated precipitation is quite complicated, with distinctly different patterns simulated among the models. There are phase differences in the multi-decadal variability of precipitation among the models, which consistently fail to detect a weakening in the precipitation at the minima of the radiative forcings. Only limited models are able to simulate the quasi-100-year solar cycles in the changes of precipitation over India and East Asia. Thus, although the climate system is certainly affected by external radiative forcings, our results imply that the natural forcings may not exert such a substantial influence on the Asian monsoon rainfall, or the models may underestimate the response. [ABSTRACT FROM AUTHOR]

ABSTRACT Dynamically downscaled agro-climates for present (1981-2010) and future (2071-2100) climates under Representative Concentration Pathways (Historical, RCP4.5, and RCP8.5) in Northeast Asia (118°-138°E, 30°-45°N) are analysed in terms of the indices, such as vegetable and crop periods, frost days, and the climatic yield potential ( CYP) for Japonica type rice (hereafter, rice). The model employed for dynamical downscaling is the Weather Research and Forecasting ( WRF), with a 12.5-km horizontal grid spacing in the domain. According to our results, the CYP for rice, one of the major crops presently cultivated in the area, is expected to decrease throughout most of the region, despite a projected expansion of both vegetable and crop periods. This is projected to occur particularly in South Korea, Japan, and Southeast and Northeast China. Such a change is related to the projected rise in temperature within these regions, which will exceed the grain-filling optimum temperature of rice. In contrast, the climate projection of the RCPs is that the CYP will increase over northeastern parts of the Korean Peninsula and the Russian Far Eastern region (Primorsky), because temperatures in these regions are expected to rise and approach the grain-filling optimum temperature. For the RCPs, the optimum heading date, on which the domain averaged CYP is the highest, is expected to be later than that of the Historical by approximately 17-24 days. In addition, the maximum CYP in the RCPs is projected to decrease compared with that of the historical, and the possible period of rice ripening (period in which the CYP is greater than 0) is also expected to decrease. [ABSTRACT FROM AUTHOR]

The sediment succession in the Bay of Bengal (BoB) records the signatures corresponding to India-Asia collision, regional climate change, and erosional processes of both the Himalayan orogen and Indian subcontinent. The Bengal Fan - the world's largest submarine fan - has long been studied to understand the link between the Himalayan tectonics and Asian monsoon. But, lack of detailed information on corresponding signals hampered the understanding of related processes of tectonics, climate and erosion. The present study of long-streamer seismic reflection profile data and information from deep drill well logs in the western BoB has revealed two different phases of sediment deposition. In the first phase, until Oligocene- Miocene (∼23 Ma), Indian peninsular rivers discharged sediments to the BoB which accumulated at a rate ∼20 m/m.y. with an aberration of twofairly enhanced sediment pulses during the periods from 65 to 54 Ma and 34 to 23 Ma. In the second phase, since 23 Ma, the Ganges and Brahmaputra rivers added huge volumes of sediments to the bay at variable rates ranging from 40 to >1000 m/m.y. A distinct increase in sediment discharge (∼140 m/m.y.) during the Oligocene- Miocene (∼23 Ma) together with the development of regional onlap unconformity and the start of turbidity system provide an important age marker corresponding to rapid exhumation of the Himalaya, which intensified the erosional process and commencement of Bengal Fan sedimentation. Further rise in the rate of sedimentation during the period 6.8-0.8 Ma is coincident with the change in monsoon intensity, but surprisingly not in agreement with the decrease in sediment rate reported at ODP Leg 116 sites in the distal Bengal Fan. Here we provide wellconstrained ages for the commencement and growth of the Bengal Fan, which can serve as benchmark information for understanding the interaction between the Himalayan exhumation and Asian climate. [ABSTRACT FROM AUTHOR]

This paper describes two dominant patterns of Asian winter climate variability: the Siberian high (SH) pattern and the Asia-Arctic (AA) pattern. The former depicts atmospheric variability closely associated with the intensity of the Siberian high, and the latter characterizes the teleconnection pattern of atmospheric variability between Asia and the Arctic, which is distinct from the Arctic Oscillation (AO). The AA pattern plays more important roles in regulating winter precipitation and the 850-hPa meridional wind component over East Asia than the SH pattern, which controls surface air temperature variability over East Asia. In the Arctic Ocean and its marginal seas, sea ice loss in both autumn and winter could bring the positive phase of the SH pattern or cause the negative phase of the AA pattern. The latter corresponds to a weakened East Asian winter monsoon (EAWM) and enhanced winter precipitation in the midlatitudes of the Asian continent and East Asia. For the SH pattern, sea ice loss in the prior autumn emerges in the Siberian marginal seas, and winter loss mainly occurs in the Barents Sea, Labrador Sea, and Davis Strait. For the AA pattern, sea ice loss in the prior autumn is observed in the Barents-Kara Seas, the western Laptev Sea, and the Beaufort Sea, and winter loss only occurs in some areas of the Barents Sea, the Labrador Sea, and Davis Strait. Simulation experiments with observed sea ice forcing also support that Arctic sea ice loss may favor frequent occurrence of the negative phase of the AA pattern. The results also imply that the relationship between Arctic sea ice loss and winter atmospheric variability over East Asia is unstable, which is a challenge for predicting the EAWM based on Arctic sea ice loss. [ABSTRACT FROM AUTHOR]

In this study, the authors apply an efficient sampling approach and conduct a large number of simulations to explore the sensitivity of the simulated Asian summer monsoon (ASM) precipitation, including the climatological state and interannual variability, to eight parameters related to the cloud and precipitation processes in the Beijing Climate Center AGCM, version 2.1 (BCC_AGCM2.1). The results herein show that BCC_AGCM2.1 has large biases in simulating the ASM precipitation. The precipitation efficiency and evaporation coefficient for deep convection are the most sensitive parameters in simulating the ASM precipitation. With optimal parameter values, the simulated precipitation climatology could be remarkably improved, including increased precipitation over the equatorial Indian Ocean, suppressed precipitation over the Philippine Sea, and more realistic mei-yu distribution over eastern China. The ASM precipitation interannual variability is further analyzed, with a focus on the ENSO impacts. It is shown that simulations with better ASM precipitation climatology can also produce more realistic precipitation anomalies during El Niño-decaying summer. In the low-skill experiments for precipitation climatology, the ENSO-induced precipitation anomalies are most significant over continents (vs over ocean in observations) in the South Asian monsoon region. More realistic results are derived from the higher-skill experiments with stronger anomalies over the Indian Ocean and weaker anomalies over India and the western Pacific Ocean, favoring more evident easterly anomalies forced by the tropical Indian Ocean warming and stronger Indian Ocean-western Pacific teleconnection as observed. The model results reveal a strong connection between the simulated ASM precipitation climatological state and interannual variability in BCC_AGCM2.1 when key parameters are perturbed. [ABSTRACT FROM AUTHOR]

The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropogenic emissions continue to rise throughout the 21st century (i.e. RCP8.5) by all realizations from four Chinese models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Delayed onset of the monsoon over the Arabian Sea was evident in all simulations for present-day climate, which was associated with a too weak simulation of the low-level Somali jet in May. A consistent advanced onset of the monsoon was found only over the Arabian Sea in the projections, where the advanced onset of the monsoon was accompanied by an increase of rainfall and an anomalous anticyclone over the northern Indian Ocean. In all the models except FGOALS-g2, the enhanced low-level Somali jet transported more water vapor to the Arabian Sea, whereas in FGOALS-g2 the enhanced rainfall was determined more by the increased wind convergence. Furthermore, and again in all models except FGOALS-g2, the equatorial SST warming, with maximum increase over the eastern Pacific, enhanced convection in the central West Pacific and reduced convection over the eastern Indian Ocean and Maritime Continent region, which drove the anomalous anticyclonic circulation over the western Indian Ocean. In contrast, in FGOALS-g2, there was minimal (near-zero) warming of projected SST in the central equatorial Pacific, with decreased convection in the central West Pacific and enhanced convection over the Maritime Continent. The broader-scale differences among the models across the Pacific were related to both the differences in the projected SST pattern and in the present-day simulations. [ABSTRACT FROM AUTHOR]

The authors explore the preceding factors of summertime Asian-Pacific Oscillation (APO) using observations and output from the NCEP Climate Forecast System version 2 (CFSv2). Results show that the winter and spring sea surface temperatures (SSTs) in the tropical central-eastern Pacific (TCEP) and the spring sea level pressure (SLP) over the north Indian Ocean (NIO) are significantly correlated with summer APO. The preceding TCEP SST anomaly tends to exert a delayed impact on summer APO through the following process. The previous winter TCEP SST anomaly persists until spring and results in SLP anomaly over the NIO in spring. The latter induces a vertical motion anomaly over the western Tibetan Plateau, which alters spring rainfall and underlying soil moisture in situ, further modulating local surface air temperature during the following summer and hence the summer APO. The CFSv2 has high skills in predicting the winter and spring TCEP SST and the spring NIO SLP and successfully captures the observed relationships of TCEP SST and NIO SLP with summer APO. This result explains why the CFSv2 is capable of predicting the summer APO teleconnection by several months in advance. [ABSTRACT FROM AUTHOR]

The climatic effect of Tibetan Plateau (TP) uplift is a hot topic in paleoclimate research. In this paper, the results of a set of numerical simulations are reported to analyze the impact of regional TP uplift on the Asian monsoon climate. The focus is on the impact of the regional uplift in the west and east parts on South Asian summer monsoon, as well as the impact of regional uplift on East Asian winter monsoon. The results show that the uplifts of the Himalaya and the central-southern TP have little effect on summer precipitation increasing over South Asia. Whereas, the further uplifts of the TP in the west and east parts, including the uplifts of both the eastern and western TP, have important effects on the strengthening of the South Asian summer monsoon. The uplift of the eastern TP leads to low-level cyclonic circulation anomalies appearing in the Bay of Bengal, accompanied by anomalous upward movement, and in turn precipitation markedly increases in the Bay of Bengal. Whereas, the uplift of the western TP produces low-level cyclonic circulation anomalies around the uplifted region and intensifies the moisture transport from the tropical ocean, and thus precipitation further increases in South Asia, especially in the northern Arabian Sea. The strengthened summer monsoon in South Asia is coupled with the intensification in diabatic heating and moisture convergence. For the East Asian winter monsoon, the intensification of winter monsoon winds is related more to the regional uplifts than the uplift of the whole TP. The uplifts of the central-southern TP, the northern TP and other northern topography have greater effects on the strengthening of the winter monsoon winds. [ABSTRACT FROM AUTHOR]

This study provides a detailed analysis of the mid-Holocene to present-day precipitation change in the Asian monsoon region. We compare for the first time results of high resolution climate model simulations with a standardised set of mid-Holocene moisture reconstructions. Changes in the simulated summer monsoon characteristics (onset, withdrawal, length and associated rainfall) and the mechanisms causing the Holocene precipitation changes are investigated. According to the model, most parts of the Indian subcontinent received more precipitation (up to 5 mm/day) at mid-Holocene than at present-day. This is related to a stronger Indian summer monsoon accompanied by an intensified vertically integrated moisture flux convergence. The East Asian monsoon region exhibits local inhomogeneities in the simulated annual precipitation signal. The sign of this signal depends on the balance of decreased pre-monsoon and increased monsoon precipitation at mid-Holocene compared to present-day. Hence, rainfall changes in the East Asian monsoon domain are not solely associated with modifications in the summer monsoon circulation but also depend on changes in the mid-latitudinal westerly wind system that dominates the circulation during the pre-monsoon season. The proxy-based climate reconstructions confirm the regional dissimilarities in the annual precipitation signal and agree well with the model results. Our results highlight the importance of including the pre-monsoon season in climate studies of the Asian monsoon system and point out the complex response of this system to the Holocene insolation forcing. The comparison with a coarse climate model simulation reveals that this complex response can only be resolved in high resolution simulations. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents and optimizes the annual heating, cooling and lighting energy consumption associated with applying different types and properties of window systems in a building envelope. Through using building simulation modeling, various window properties such as U-value, solar heat gain coefficient (SHGC), and visible transmittance (Tvis) are evaluated with different window wall ratios (WWRs) and orientations in five typical Asian climates: Manila, Taipei, Shanghai, Seoul and Sapporo. By means of a regression analysis, simple charts for the relationship between window properties and building energy performance are presented as a function of U-value, SHGC, Tvis, WWR, solar aperture, effective aperture, and orientation. As a design guideline in selecting energy saving windows, an optimized window system for each climate is plotted in detailed charts and tables. [Copyright &y& Elsevier]

Based on the comprehensive hydrochemical and hydrobiological studies of the Selenga River near the Naushki settlement carried out in 2010, the quality of water flowing from the territory of Mongolia is assessed. The comparison with the results of the previous years indicates that the water quality deteriorated due to the intensification of economic activity in the river basin and unfavorable climatic factors. [ABSTRACT FROM AUTHOR]

South Asia covers more than 30° of latitude with weather observation stations situated from 6°N at Galle, Sri Lanka, to 36°N at Chitral in Pakistan. Moreover, the South Asian station network ranges in altitude from sea level to nearly 4000 m above sea level. This paper uses time series of 11 objectively defined indices of daily temperature extremes at 197 stations in Bangladesh, India, Nepal, Pakistan and Sri Lanka to examine the possible impacts of elevation and latitude on changes in temperature extremes over the period of 1971-2000. Trends in extreme indices are consistent with general warming only at low altitudes and latitudes. Stations at high altitudes and latitudes show both positive and negative trends in extreme temperature indices. As a notable example, the Diurnal Temperature Range (DTR), which has been known to decrease in most parts of the globe, has increasing trends over many high altitude stations in South Asia. Trends in extreme temperature indices at stations in South Asia higher than 2000 m above sea level are mostly in disagreement with those reported over the Tibetan Plateau. Observed trends at low altitude locations in South Asia suggest that these sites can generally expect future changes in temperature extremes that are consistent with broad-scale warming. High-elevation sites appear to be more influenced by local factors and, hence, future changes in temperature extremes may be less predictable for these locations. Copyright © 2012 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The article presents a study that was conducted to estimate the influence of geological, geomorphological, hydrogeochemical, and climatic factors on accumulation of uranium. It further investigates forms of uranium deposition in the lake systems of Western Mongolia with reference to the example of the uranium-bearing soda Shaazgai Nuur Lake. It informs that the investigation of the lake was performed during the International Interdisciplinary Russian-Mongolian Hydrogeochemical Expedition in 2011.

Abstract: Pastoralism represents a complex adaptive system that has existed in Inner Asia for thousands of years. The challenges of environmental change have highlighted the need to assess the potential for long-term sustainability while also considering the characteristics of systems that have the potential to maintain resilience. Here we assess the interaction between slow and fast processes and how interpretations of adaptive capacity and system resilience are affected by the scale at which observations are made. Agent-based modeling is used to identify the social and demographic interactions between landscape and weather variability for pastoralists in Inner Asia at a variety of social scales and from temporal scales of societal change ranging from a few days to 1000 years. Results indicate that the scale of abrupt changes may not be proportional to the severity or duration of the weather event, but is highly impacted by internal social factors. At the scale of individual families, highly interconnected social systems with less mobility and restricted decision making are less effective. When viewed from the vantage point of larger social units, highly interconnected kinship systems and restrictions in access to land may serve purposes that are counterproductive for individual families. [Copyright &y& Elsevier]

In the mid-latitude regions of the Asian continent, Zhuye Lake is located in the northwest margin of the Asian monsoon, where the modern climate is affected by the Asian monsoon and Westerlies. In this study, we investigated the absolutely dated Holocene records in Zhuye Lake for detecting the Holocene climate cycles. Totally, 14 C dates and 6 optically simulated luminescence (OSL) dates are obtained from the QTH01 and QTH02 sections. The proxies of grain-size, total organic carbon content (TOC), C/N and δC are used for wavelet analysis, and the results show obvious ∼256, ∼512 and ∼1024-year climate cycles, which are consistent with the Holocene millennial and centennial scale climate cycles in the typical Asian summer monsoon domain. In different parts of the Zhuye Lake, the Holocene sediments show variable climate cycles that are affected by the lake basin topography. In the Zhuye Lake, the Holocene climate cycles are mainly correlated with the solar-related Asian summer monsoon variability and the North Atlantic ice-rafting events. [ABSTRACT FROM AUTHOR]

The mechanism and factors of the impact of climate changes on the level regime of bog water and the runoff from bogs has been established. [ABSTRACT FROM AUTHOR]

Abstract: As an index denoting vegetation cover, NDVI is influenced by many climatic factors such as precipitation and average temperature. In this paper, NDVI is calculated on the basis of waveband characteristic of NOAA/AVHRR data for the YarlungZangbo River Basin. Then, the spatial-temporal change of NDVI is analyzed. The basin''s NDVI is in consistency with season from 2001 to 2003.Large value zone of NDVI is mainly distributed in the lower reaches and part of the middle reaches. Meanwhile, point-data of principal climatic factors are interpolated to spatial grid data with Kriging method consistent with NDVI based on DEM of the YarlungZangbo River Basin. Then, the relation of NDVI and precipitation or average air temperature is analyzed with F checking and two-sample variance test in the basin. The result is P=0, which shows that correlation analysis has larger confidence. The linear and logarithmic correlation of NDVI and precipitation or average air temperature is analyzed at confidence level of 0.05.The conclusion is that NDVI and precipitation and average air temperature in the basin vary with seasons and are closely correlated. The linear correlation coefficient of NDVI and precipitation is 0.8, and that of NDVI and average air temperature is about 0.77.And the logarithmic correlation coefficient of NDVI and precipitation is 0.71, and that of NDVI and average air temperature is 0.7. [Copyright &y& Elsevier]

Abstract: The South China Sea throughflow (SCSTF) involves the inflow through the Luzon strait and the outflow through the Karimata, Mindoro, and Taiwan straits. Recent studies have suggested that the SCSTF act as a heat and freshwater conveyor, playing a potentially important role in regulating the sea surface temperature pattern in the South China Sea and its adjoining tropical Indian and Pacific Oceans. In this introductory paper, we attempt to convey the progress that has recently been made in understanding the SCSTF. We first provide an overview of existing observations, theories, and simulations of the SCSTF. Then, we discuss its interaction with the Pacific western boundary current and Indonesian throughflow. Finally, we summarize issues and questions that remain to be addressed, with special reference to the SCSTF''s dynamics, variability, and implication for climate. [Copyright &y& Elsevier]

The article summarizes the temperature and precipitation conditions across Asia in 2013. Topics discussed include the above normal annual mean surface air temperatures in large areas of the Eurasian continent, the below normal temperatures in parts of northeastern Asia, and the annual precipitation ratio relative to the 1981 to 2010 base period.

We examine the links between the thermal condition of the troposphere over the Tibetan Plateau with the atmospheric circulation and climate over the Eurasian continent. The temperature of the troposphere over the Tibetan Plateau is higher than the temperature in other regions at the same latitude and is consistent with the temperature of the Eurasian troposphere on an interannual timescale. The higher temperature of the troposphere over the Tibetan Plateau leads to anomalous south–north temperature gradients from mid-latitudes over the Eurasian continent to its two flanks, accompanied by anomalous easterly and westerly winds in the upper troposphere in the subtropics and at higher latitudes. Anomalous anticyclonic circulations and subsidence motions appear between the anomalous easterly and westerly winds and contribute to the high surface air temperature over West Asia, Central Asia and East Asia via anomalous vertical temperature advection in the troposphere and change in the amount of solar radiation incident on the surface. The enhanced East Asian summer monsoon associated with the high temperature of the troposphere over the Tibetan Plateau also partly contributes to the high surface air temperature over East Asia via horizontal temperature advection. The westerly wind anomalies in the north of the mid-latitudes over the Eurasian continent indicate the enhancement and northward shift of the mid-latitude westerly jet. This is related to anomalous upward motion and higher precipitation in Northeast China and North China. Sensitivity experiments based on an atmospheric model verify the impact of anomalous tropospheric heating over the Tibetan Plateau in summer on the atmospheric circulation over the Eurasian continent. • The Tibetan tropospheric temperature is coincident with the Eurasian tropospheric temperature at interannual time scales. • The Tibetan tropospheric temperature anomaly can change the intensity and position of the mid-latitude westerly jet. • The thermal condition of the Tibetan Plateau is related to SAT anomalies over West Asia, Central Asia, and East Asia. [ABSTRACT FROM AUTHOR]