The dynamics of permafrost (including the permafrost thermal state and active layer thicknesses (ALT)) across the Qinghai‐Tibetan Plateau (QTP) have not been well understood on a large scale. Here we simulate the ALT and permafrost thermal state using the Geophysical Institute Permafrost Lab version 2 (GIPL2) model across the QTP. Based on the single‐point simulations, the model is upscaled to the entire QTP. The upscaled model is validated with five investigated regions (IRs), including Wenquan (WQIR), Gaize (GZIR), Aerjin (AEJIR), Xikunlun (XKLIR), and Qinghai‐Tibetan Highway (G109IR). The results show that the modified GIPL2 model improves the accuracy of the permafrost thermal state simulations. Due to our simulated results on the QTP, the average ALT is of 2.30 m (2.21–2.40 m). The ALT decreases with an increase in the altitude and decreases from the southeast to the northwest. The ALT is thin in the central QTP, but it is thick in the high‐elevation mountain areas and some areas surrounding glaciers and lakes. The largest ALT is found in the border areas between permafrost and seasonally frozen ground regions. The simulated results of the MAGT (the mean annual ground temperature) indicate that most of the permafrost is substable, which is sensitive to climate warming. The simulated results would be of great significance on assessing the impacts of permafrost dynamics on local hydrology, ecology, and engineering construction.

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A relatively new addition to the application portfolio of lead halide perovskites is to photosensitize molecular triplets for a variety of photochemical applications. Here we report visible-light-driven isomerization and cycloaddition of organic molecules sensitized by spectrally-tunable perovskite nanocrystals. We first demonstrate with stilbene as the substrate molecule that photoisomerization can proceed efficiently and rapidly by either directly grafting carboxylated stilbene onto nanocrystal surfaces or using triplet-acceptor ligands as the energy relay. The relay approach is more generally applicable as it does not require anchoring-group functionalization of substrate molecules, allowing us to facilely extend it to isomerization of a series of substituted stilbene molecules and ring-closing isomerization of diarylethene, as well as intermolecular [2+2] cycloaddition of acenaphthylene. This study opens an avenue of energy-transfer photocatalysis using perovskite nanocrystals.