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The nature, extension, and evolution of the Meso-Tethys still remain unclear to researchers, and this has thereby hindered in-depth study of the Tethys tectonic domain. In this paper, we review the geology of the Tethys tectonic domain and suggest that the Meso-Tethys is a massive tectonic zone divided into three segments. The central segment includes the Bangong-Nujiang Suture Zone on the Tibetan Plateau and the Shyok Suture Zone in the South Pamir Mountains. This segment has been well studied and is the key link that fully records the birth, evolution, and demise of the Meso-Tethys Ocean from the Permian to Cretaceous, as well as the subsequent continental collision and crustal uplift. The western segment includes the Sanandaj-Sirjan Suture Zone and the Izmir-Ankara-Erzincan Suture Zone in the Middle East. Due to limited research on the western segment, our understanding of it is mainly derived from records of the Jurassic forearc extension,development of arc, and subsequent arc-continent collision. The eastern segment includes the Shan Boundary in Southeast Asia. It has received widespread attention in recent years, and it contains complete records of the Jurassic subduction of the Meso-Tethys Ocean. Based on the latest comprehensive data, we propose that the evolution of the Meso-Tethys Ocean can be divided into four stages: (1) the Early Permian rifting and opening stage; (2) the Middle Permian-Triassic seafoor spreading stage; (3) the Late Triassic-Jurassic convergence stage; and (4) the Late Jurassic-Early Cretaceous diachronous closure from east to west in the central segment and transition from the Meso-Tethys evolution to the Neo-Tethys evolution in both the eastern and western segments. The Meso-Tethys Ocean underwent complex evolution for at least ∼160 Myrs. It has an east-west length of over 8000 km and a maximum north-south width of close to 5000 km during the Late Triassic, which basically reached the scale of the current Indian Ocean. It was an important ocean basin that coexisted with the Paleo- and Neo-Tethys oceans, a key intermediate link in the evolution of the Tethys, and one of the major contributors to the continuous disintegration of Gondwana and the accretion of the Eurasian continent. Its complex evolution process and multiple periods of accretion resulted in the formation of complex geological records and the wide scale of the Meso-Tethys (e.g., the Bangong-Nujiang Suture Zone), making this area a rare natural laboratory for in-depth study of orogenesis, which is of great significance for studying tectonic processes on the global scale from seafloor geology to continental accretion and mineralization. [ABSTRACT FROM AUTHOR]

Abstract Global warming has already had a significant impact on social ecosystems. The Tibetan Plateau (TP), which is characterized by a cryosphere, is also recognized to have a profound influence on regional and global climate systems, as well as the ecological economy. Therefore, research on the cryosphere is of significant importance. This paper comprehensively reviews the current status and recent changes of the cryosphere (e.g., glacier, snow cover, and frozen ground) in the TP from the perspectives of observations and simulations. Because of enhanced climate warming in the TP, a large portion of glaciers have experienced significant retreat since the 1960s, with obvious regional differences. The retreat is the smallest in the TP interior, and gradually increases towards the edges. Glacier simulations are comparatively few and still under development. Snow cover is a highly sensitive element of the cryosphere and decreases with large interdecadal variations from the 1960s to the 2010s in general. Simulations of snow cover mostly focus on the mutual feedback between the snow cover anomaly, climate and atmospheric circulation. In situ observations and simulations both indicate that the mean annual temperature of frozen ground increases, causing permafrost thaw and degradation and decreasing the seasonal freeze depth of seasonally frozen ground. Under future climate warming, the cryospheric elements in the TP will continue to diminish on the whole. Studies of climate and the cryosphere are ongoing. To date, the lack of observations is the biggest challenge on the TP, resulting in a divergence of cryosphere dynamics and its simulation being a bottleneck. To overcome these issues, a strategy that combines sets of in situ and remote sensing measurements and improved numerical models is of great importance for achieving breakthroughs with respect to research on the TP cryosphere and its interaction with climate. [ABSTRACT FROM AUTHOR]

Paleomagnetic data have long been used to hypothesize that the Cenozoic extrusion of the Indochina Block along the left-lateral Ailao Shan-Red River fault, as a result of the India-Asia collision, may have been associated with a major southward paleolatitude shift of as much as 10–15°, and a vertical-axis rotation of as much as 25–40°. However, although numerous paleomagnetic studies have been conducted in the southeast margin of the Tibetan Plateau and in the Indochina region during the last few decades, the detailed rotation as well as the latitudinal displacement of the Indochina Block remain controversial because of apparently contradicting paleomagnetic results. Geological constraints also yield contrasting estimates on the amount of displacement along different segment of the Ailao Shan-Red River fault: 700 ± 200 km in the northwest, but only ~ 250 km in the southeast. In this paper, the available paleomagnetic data from the southeast margin of the Tibetan Plateau and Indochina, as well as the South China Block, from Jurassic and younger rocks are compiled and critically reviewed using the new paleomagnetic toolkit on Paleomagnetism.org . Our results show that (1) the South China Block has declinations that reveal no significant rotations relative to Eurasia since latest Jurassic. Inclinations are consistently shallower than expected, which is likely the result of inclination shallowing in sedimentary rocks; (2) there is no paleomagnetically resolvable southward motion of the Indochina Block with respect to Eurasia based on the paleomagnetic data. Paleomagnetic inclinations are in fact lower than expected, probably due to inclination shallowing in sediments; (3) paleomagnetic declinations reveal large, more or less coherently rotating blocks in the northern Indochina domain and the SE Tibetan margin that rotated up to 70° clockwise, much more than the ~ 10–15° rotation of the stable, SE part of the Indochina Block. These blocks are bounded by fold-thrust belts and strike-slip faults, which we interpret to have accommodated these block rotations during the Cenozoic. We designed a new tool on the online open-access portal Paleomagnetism.org that allows testing whether Euler rotations in a kinematic reconstruction fulfill paleomagnetic data. Using this tool, we built a first-order kinematic reconstruction of rotational deformation of northwest Indochina in Cenozoic. We show that the northwestern part of Indochina extruded 350 km more along the Ailao Shan-Red River fault than the southeastern part accommodated by internal northwest Indochina rotation and deformation. Estimates of 250 km of extrusion of the southeastern part of the Indochina then predicts ~ 600 km of left-lateral motion along the northwestern part of the Ailao Shan-Red River fault, which reconciles the small and large estimates that prevail in the literature of extrusion of Indochina from the Tibetan realm during the Cenozoic India-Asia collision. [ABSTRACT FROM AUTHOR]

This paper reviews the spatial-temporal distribution, geological and geochemical features, and geophysical context of diverse types of Cenozoic ore deposits formed during India-Eurasia continental collision in Tibet, in order to shed new light on their genesis and their control by mantle lithosphere. The parental magmas for porphyry-skarn Cu (± Mo ± Au) deposits were derived from metal-rich pre-Cenozoic juvenile crust, and the high magma oxidation state was controlled by involved mantle-derived basic magmas and thickened crust condition; magma emplacement was controlled by structures related both to tears in the subducting continental slab to deep and to mantle-crust decoupling parts at depth. Orogenic Au deposits mostly formed intermittently from hydrothermal fluids formed by devolatilization of earlier-fertilized mantle lithosphere that was triggered by asthenosphere upwelling; they were largely controlled by lithosphere-scale shear systems that reactivated earlier-formed suture zones. Giant MVT Zn Pb deposits, hosted by ancient oil reservoirs, formed during salt diapirism and infiltration of metal-rich basinal brines related to crustal-scale channel flow. The diverse range of ore deposits was derived predominantly through release of metal and fluid components, introduced into the crust and mantle lithosphere that occurred in the earlier oceanic subduction during anomalous lithosphere-scale deformation. The metallogenic history of collisional orogens contrasts with those of accretionary orogens. • Tibetan mineralization system provides an important global insight into metallogenesis during continental collision. • Lithosphere architecture and fertility formed by oceanic subduction control diverse ore deposits in collision setting. • Diverse types of Tibetan ore deposits have different genesis to those from oceanic subduction settings. • Tibetan ore deposits formed in various geodynamic settings of thrusting, shearing, rotation, and rifting. [ABSTRACT FROM AUTHOR]

This paper reviews progress in the study of aerosol-cloud interactions over the Tibetan Plateau (TP) in the past decade. Clarifying the aerosol-cloud-precipitation interactions over the TP is an important issue for both local and downstream precipitation forecasts. By exerting a "dynamic pump" effect due to the elevated heat source in summer, the TP acts as a "transfer station" for aerosols and water vapor, possessing abundant water vapor and enough cloud condensation nuclei (CCN) and ice nuclei (IN) in cloud physical processes. We found that mixtures of aerosols and clouds are frequently observed over the margin areas of the TP, especially the mixture between aerosols and ice clouds. The convective clouds over the TP could be affected by the Taklimakan dusts lifted from the north slope of the TP, inducing higher and more invigorated convective clouds locally. Furthermore, the dust-polluted convective clouds can continuously move eastward and merge with the convective cloud clusters along their motion paths, inducing more intensive rainfall over the downstream regions of the TP. Finally, challenges to further understanding aerosol-cloud interactions over the TP in the future are discussed. [ABSTRACT FROM AUTHOR]

In their thoughtful paper entitled "An equable subtropical climate throughout China in the Miocene based on palaeofloral evidence", Qing Wang, Yan Li, David K. Ferguson, Wen-Bo Mo, and Nan Yang (2021) imply that China exhibited negligible latitudinal mean annual precipitation (MAP) gradients and lacked arid regions during the Miocene. They also speculate that there was no abrupt change in elevation of the Tibetan Plateau, nor that the plateau attained its present altitude or orography during that period. These conclusions were derived mainly by using a co-existence approach (CA) and 'incomplete data'. Here, we use CA with training data and also integrate a coexistence likelihood estimation, a pollen-MAP boundary, a desert-MAP boundary, and other newly published MAP data to show that Northwest China consistently exhibited drier conditions than South China and East China during the entire Miocene, with our new values being 300–500 mm lower than those of Wang et al. (2021). This implies that there were large spatial gradients of MAP in China during the Miocene, which may be directly linked with the growth of the Tibetan Plateau, the global cooling, as well as other factors. We recommend the comprehensive consideration of multiple methods and proxies for reconstructing past climate conditions as opposed to a single proxy. [ABSTRACT FROM AUTHOR]

Known as the "third pole" and "water tower of Asia", the Tibetan Plateau (TP) is the home to the largest number of glaciers in the mid-latitudes and one of the most sensitive areas to global climate change due to its special geographical location and powerful thermodynamic effects. In recent years, the TP has been affected by exogenous pollutants and the concentrations of some pollutants have shown an increasing trend, especially light-absorbing aerosols (LAAs), when ice core records, ground- and aircraft-based field campaigns and satellite technology enabled synthesized monitoring. The enhanced warming of the vast majority of regions in TP, together with Arctic warming, and snow/ice decline, represents credible evidence of anthropogenic climate change. This paper provides a comprehensive review of studies on the sources, characteristics and climate impacts of LAAs over the TP. Adjacent to the two major emission sources of LAAs in East Asia and South Asia, the unique geographical location and climatic characteristics of the TP make it possible for TP LAAs to cause atmospheric warming and accelerated glacier melting, affecting the hydrological cycle in South Asia, East Asia and even the Northern Hemisphere, thus causing a series of serious environmental and social problems. LAAs, such as black carbon and dust, can strongly absorb solar radiation and and have significantly influence on climate change. Moreover, light-absorbing impurities (LAIs) on snow/ice can reduce the snow/ice albedo and further accelerate the snow/ice melting. Both LAAs and LAIs over the TP can induce thermodynamic feedback processes, cause significant warming of the TP and then lead to a strengthening of the early monsoon and affect the subsequent evolution of the monsoon. Many mechanisms have been proposed forth regarding how TP LAAs modulate the phase, intensity, and amplitude of the Asian climate system. A wide range of theoretical, observational, and modeling findings on TP LAAs and their climate impacts are synthesized, in which dust aerosols from drylands and black carbon from biomass burning are considered leading components. By coupling an integrated approach with state-of-the-art modeling, high temporal and fine spatial resolution remote sensing observations with increasing sampling over the TP will provide further insights into TP aerosols. • Light-absorbing aerosols warm the Tibetan Plateau, further influence climate system • The external input of light-absorbing aerosols over the Tibetan Plateau is dominant • Climate effects of light-absorbing aerosols or impurities in snow is divergent [ABSTRACT FROM AUTHOR]

Abstract: Debate continues over whether global cooling or uplift of the Tibetan Plateau provided the first-order driver for the aridification (moisture levels) of Central Asia throughout the Mid–Late Miocene, between about 17 and 5Ma. This review attempts to throw new light on the relations between the aridification and these two key factors. This paper examines the evolution of Miocene climate (both moisture and temperature) within five separate regions of Eurasia to help understand the large scale controls of long-term moisture in Central Asia. The five regions include: (1) Europe, (2) high-latitude Asia, (3) the East Asian Monsoon region, (4) the South Asian Monsoon region, and (5) Central Asia itself, because moisture reaching Central Asia has to firstly cross at least one of the other four regions. Temperature proxy data compiled from these five regions correlate with ocean temperatures from the global deep-sea oxygen isotope records. Furthermore, compiled moisture proxy data from the four regions surrounding Central Asia co-vary and correlate with each other. This can be explained by positive feedbacks between drying and cooling, and supports the assumption that global cooling provides a dominant driving factor for the drying of Eurasia: global cooling reduces the amount of water vapor held in the atmosphere and thereby can cause terrestrial drying. However, in Central Asia the moisture evolution shows less similarity with its surroundings. The uplift of the Tibetan Plateau (including the Tianshan Mountains) could provide a possible explanation for this difference. The changing topography resulting from uplift events over time and space strongly influenced the moisture patterns in Central Asia during Miocene times. Future research on the spatial timing and amplitude of Tibetan Plateau uplift should be useful to understand the moisture processes in Central Asia during the Miocene. [Copyright &y& Elsevier]