The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998–2013 (0.25 °C decade⁻¹), compared with that during 1980–1997 (0.21 °C decade⁻¹). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud–radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998 and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud–radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau.

The relationship between Tibetan Plateau (TP) snow cover and the East Asian summer monsoon (EASM) has long been discussed, but the underlying mechanism remains controversial. In this paper, the snow–albedo and snow–hydrology feedbacks over the TP are investigated based on multiple sources of snow data for the period 1979–2011. The results indicate that winter snow cover plays an important role in cooling local air temperature through the snow–albedo effect; the TP surface net solar radiation in years with above-normal snow cover is approximately 18 W m ⁻² less than that in below-normal snow cover years. However, data analysis demonstrates that persistent effects of winter snow cover are limited to the period from winter to spring over most parts of the central and eastern TP. Therefore, the preceding snow cover over the central and eastern TP exerts little influence over either the in situ summer atmospheric heat source or the EASM, because of its limited persistence. In contrast, the effects of winter or spring snow cover anomalies over the western TP and the Himalayas can last until summer, and these anomalies further influence the EASM by modulating moisture transport to eastern China and favoring eastward-propagating synoptic disturbances that are generated over the TP. Generally, above-normal snow cover over the western TP and the Himalayas facilitates abundant summer precipitation between the Yangtze and Yellow River basins, which is confirmed by results from a regional Weather Research and Forecasting model simulation.

Temporal variability within the Tibetan Plateau summer monsoon (TPSM) is closely linked to both the East and South Asian summer monsoons over several time scales but has received much less attention than these other systems. In this study, extensive integrations under phase 5 of the Coupled Model Intercomparison Project (CMIP5) historical scenarios from 15 coupled general circulation models (CGCMs) and Atmospheric Model Intercomparison Project (AMIP) runs from eight atmospheric general circulation models (AGCMs) are used to evaluate the performance of these GCMs. Results indicate that all GCMs are able to simulate the climate mean TPSM circulation system. However, the large bias associated with precipitation intensity and patterns remains, despite the higher resolution and inclusion of the indirect effects of sulfate aerosol that have helped to improve the skill of the models to simulate the annual cycle of precipitation in both AGCMs and CGCMs. The interannual variability of the surface heat low and the Tibetan high in most of the AGCMs resembles the observation reasonably because of the prescribed forcing fields. However, only a few models were able to reproduce the observed seesaw pattern associated with the interannual variability of the TPSM and the East Asian summer monsoon (EASM). Regarding long-term trends, most models overestimated the amplitude of the tropospheric warming and the declining trend in the surface heat low between 1979 and 2005. In addition, the observed cooling trend in the upper troposphere and the decline of the Tibetan high were not reproduced by most models. Therefore, there is still significant scope for improving GCM simulations of regional climate change, especially in regions near extensive mountain ranges.

Severe landfall typhoons (SLTYs), defined as those with maximum sustained wind speed ≥41.5 m s⁻¹ at landfalls, strongly affect the coastal regions of China and cause grave losses of life and property. In this study, we analyse the SLTYs in China in peak summer (July–September) for the period of 1973–2017, during which typhoon landfall intensity (LFI) experienced significantly abrupt strengthening in 1987 and 2003. The period is divided into three sub‐periods: period‐I (1973–1987), period‐II (1988–2003), and period‐III (2004–2017). It is found that the increase in LFI is dominated by the enhancement of intensification rate but not intensification duration. Meanwhile, the SLTYs in China have also abruptly increased since 2004, characterized by the count of about 65.9% (72.7%) of SLTYs in China (South China) in period‐III. Further analysis shows that the warming subsurface ocean heat content (OHC) over the northern South China Sea (SCS) plays a key role in modulating typhoon's intensification, which subsequently enhances the easterly steering flow leading typhoons to move westward. Low‐level water vapour convergence and vorticity are enhanced accompanied by warming northern SCS along the coastal region of southeastern China, resulting rapid typhoon intensification before landfall. About 9.7% of typhoons with landfall in South China experienced a rapid intensification process in 24 hr before landfalls in period‐III. However, the percentage is only 1.6 and 3.1% for period‐I and period‐II, respectively. The warming land surface over South China plays a minor role in attracting typhoons to landfall in South China, which named as “warmward landfall”. Overall, the abrupt enhancement of LFI and more SLTYs in China since 2004 are governed by the warming ocean, while the abnormal easterly steering flow and warming land surface over South China leading typhoons to move westward play a secondary role.

The atmospheric heat source/sink (AHS) and snow cover/depth over the Tibetan Plateau (TP) in late spring play important roles in modulating the evolution of Asian summer monsoons. However, quantitative estimation of the AHS over the TP is still a large challenge because of limited observational data. In this work, both data analyses and numerical simulations from the Weather Research and Forecasting model with an updated daily snow‐depth data set are conducted to explore the intrinsic connection between the AHS and snow depth over the TP in May. Data analyses indicate that only a weak negative relationship exists between snow depth and the AHS over the western TP. On the other hand, despite the overall consistency in the spatial pattern of the AHS between the reanalysis data sets and the Weather Research and Forecasting model, a strong cooling effect (about −14.4 W/m²) appears over the western TP (32°–40°N, 70°–78°E) and the Nyenchen Tanglha Mountains in the simulation, where the altitude is above 4,000 m with thick snow cover. This characteristic is opposite to that observed in reanalysis data sets. Further analysis indicates that the underestimated atmospheric net longwave radiative cooling effect that is associated with snow depth may exaggerate the atmospheric heat source in current reanalysis data sets. Large uncertainties in the AHS still exist in current state‐of‐the‐art reanalysis data sets, especially over the regions of the TP covered by snow.