The Third Pole (TP) is experiencing rapid warming and is currently in its warmest period in the past 2,000 years. This paper reviews the latest development in multidisciplinary TP research associated with this warming. The rapid warming facilitates intense and broad glacier melt over most of the TP, although some glaciers in the northwest are advancing. By heating the atmosphere and reducing snow/ice albedo, aerosols also contribute to the glaciers melting. Glacier melt is accompanied by lake expansion and intensification of the water cycle over the TP. Precipitation has increased over the eastern and northwestern TP. Meanwhile, the TP is greening and most regions are experiencing advancing phenological trends, although over the southwest there is a spring phenological delay mainly in response to the recent decline in spring precipitation. Atmospheric and terrestrial thermal and dynamical processes over the TP affect the Asian monsoon at different scales. Recent evidence indicates substantial roles that mesoscale convective systems play in the TP’s precipitation as well as an association between soil moisture anomalies in the TP and the Indian monsoon. Moreover, an increase in geohazard events has been associated with recent environmental changes, some of which have had catastrophic consequences caused by glacial lake outbursts and landslides. Active debris flows are growing in both frequency of occurrences and spatial scale. Meanwhile, new types of disasters, such as the twin ice avalanches in Ali in 2016, are now appearing in the region. Adaptation and mitigation measures should be taken to help societies’ preparation for future environmental challenges. Some key issues for future TP studies are also discussed.

The main geological factors controlling the accumulation and yield of marine‐facies shale gas reservoirs are the focus of the current shale gas exploration and development research. In this study, the Wufeng‐Longmaxi Formation in the Dingshan area of southeast Sichuan was investigated. Shale cores underwent laboratory testing, which included the evaluation of total organic carbon (TOC), vitrinite reflectance (Ro), whole‐rock X‐ray diffraction (XRD), pore permeability, and imaging through field emission scanning electron microscopy (FE‐SEM). Based on the results of natural gamma ray spectrum logging, conventional logging, imaging logging, and seismic coherence properties, the exploration and development potential of shale gas in the Dingshan area have been discussed comprehensively. The results showed that (1) layer No. 4 (WF2‐LM4) of the Wufeng‐Longmaxi Formation has a Th/U ratio <2 and a Th/K ratio of 3.5‐12. Graptolites and pyrite are relatively abundant in the shale core, indicating sub‐high‐energy and low‐energy marine‐facies anoxic reducing environments. (2) The organic matter is mainly I‐type kerogen with a small amount of II1‐type kerogen. There is a good correlation among TOC, Ro, gas content, and brittle minerals; the fracturing property (brittleness) is 57.3%. Organic and inorganic pores are moderately developed. A higher pressure coefficient is correlated with the increase in porosity and the decrease in permeability. (3) The DY1 well of the shale gas reservoir was affected by natural defects and important late‐stage double destructive effects, and it is poorly preserved. The DY2 well is located far from the Qiyueshan Fault. Large faults are absent, and upward fractures in the Longmaxi Formation are poorly developed. The well is affected by low tectonic deformation intensity, and it is well preserved. (4) The Dingshan area is located at the junction of the two sedimentary centers of Jiaoshiba and Changning. The thickness of the high‐quality shale interval (WF2‐LM4) is relatively small, which may be an important reason for the unstable production of shale gas thus far. Based on the systematic analysis of the geological factors controlling high‐yield shale gas enrichment in the Dingshan area, and the comparative analysis with the surrounding typical exploration areas, the geological understanding of marine shale gas enrichment in southern China has been improved. Therefore, this study can provide a useful reference for shale gas exploration and further development.

Knowledge of the quantitative importance of moisture transport pathways of the Sanjiangyuan region (known as the “water tower” of China) can provide insights into the regional atmospheric branch of the hydrological cycle over the Sanjiangyuan region. A combined method with a clustering algorithm [Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN)] and a Lagrangian moisture source diagnostic is developed to identify the major moisture transport pathways and quantify their importance to three types of consecutive precipitation events—extreme precipitation (EP) events, moderate precipitation (MP) events, and extreme aridity (EA) events—for the Sanjiangyuan region during the rainy season (June–September 1960–2017). The results indicate that moisture paths from the northwest covering northwest China and central Asia (the N.W. pathway) and moisture paths from southern and southeastern China (the S.S. pathway) are stable moisture transport pathways during EP and MP events [importance (precipitation contribution in percentage): N.W. pathway, 18.4% (EP), 32.2% (MP); S.S. pathway, 25.9% (EP), 28.5% (MP)]. Affected by the western edge of a significant anticyclone anomaly centered around 35°N, 115°E, the moisture paths via the Bay of Bengal (the B.B. pathway) can reach the target region and become a supplementary moisture contributor (14.9%) to EP events. Moisture paths via the Arabian Sea and Indian peninsula (the A.I. pathway) are also active but the contributions are limited [4.9% (EP) and 5.6% (MP)]. For EA events, the fast-moving trajectories from farther western Asia (the F.W. pathway) play a dominant role and all major moisture pathways (F.W., N.W., and S.S. pathways) carry limited moisture to the target region.

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