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Exceptionally strong summertime warming occurred over the Mongolian Plateau between 1986 and 2004, at a rate that was three times the average terrestrial warming in the Northern Hemisphere. The physical processes responsible for this extreme warming remain unclear. Here we show that the synchronous phase shift of the Interdecadal Pacific Oscillation and the Atlantic Multidecadal Oscillation contributed to this extreme Mongolian Plateau warming, which cannot be fully explained by the increasing anthropogenic CO 2 alone. Pacemaker model experiments show that the Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation excited an atmospheric wave train, resulting in an upper-level anticyclonic circulation over the Mongolian Plateau. This anticyclonic circulation increased surface warming by enhancing downward solar radiation, and the surface warming was further boosted by positive land–atmosphere feedbacks. Our results highlight the important role of internal climate variability in driving rapid regional climate change over the Mongolian Plateau. Relatively strong warming over the Mongolian Plateau in recent decades can be explained, in part, by synchronous internal climate oscillations, according to climate model experiments.

Southern China spring rainfall (SCSR) is significant for agricultural sowing and soil moisture accumulation before the rainy summer. A better prediction of the rainfall improves our ability to risk response to natural disasters. It is found that the SCSR can be promoted by multi‐year El Niño events through the high‐latitude pathway (HP) and low‐latitude pathway (LP). The long‐lasting El Niño warming heats the tropical troposphere persistently until the decaying spring, which strengthens the Arctic polar vortex and the mid‐latitude blockings. This HP is in favor of more southward transport of Rossby wave energy and cold air, resulting in strong ascending motions over southern China (SC) in spring. The multi‐year El Niño also induces an enhanced western North Pacific anticyclone and a secondary circulation transporting moisture to SC through the LP. The HP is more important in the early spring, while the LP dominates the heavy SCSR in the late spring. Plain Language Summary Southern China (SC) experiences a period of rainy time in spring, with the rainband located from South China to the Yangtze River. The southern China spring rainfall (SCSR) is influential for agriculture and soil moisture accumulation before the flood season in summer. A better prediction of the SCSR improves our ability to risk response to natural disasters. El Niño‐Southern Oscillation (ENSO) is the dominant climate signal that exerts significant remote impacts, especially in East Asia. However, whether it can help to predict the SCSR is still unclear. In this study, we show that a particular type of ENSO event, the multi‐year El Niño, initiates remarkable impacts on the SCSR. The long‐lasting Pacific warming favors a HP that transports more cold air and wave energy southward to SC during the decaying spring. Moreover, it also strengthens the western North Pacific anticyclone and generates a meridional secondary circulation with low‐level moisture transport toward SC. The low‐latitude and HPs collaborate to generate strong ascending motions and water vapor convergence in SC, being responsible for the large SCSR. Thus, the remote climate impact of multi‐year ENSO events is distinctive from the other ENSO events. Key Points Multi‐year El Niño enhances southern China (SC) spring rainfall through both the low‐latitude pathway (LP) and the high‐latitude pathway (HP) Long‐lasting tropical warming supports the HP which transports wave energy and cold air to SC and exerts ascending motions These ascending motions and moisture transportation by El Niño‐induced western Pacific anticyclone can be further intensified by the LP

When atoms are accelerated in the vacuum, entanglement among atoms will degrade compared with the initial situation before the acceleration. In this study, we propose a novel and interesting view that the lost entanglement can be recovered completely when the high-dimensional spacetime is exploited, in the case that the acceleration is not too large, since the entanglement loss rate caused by the large acceleration is faster than the recovery process. We also calculate the entanglement change caused by the anti-Unruh effect and found that the lost entanglement could just be recovered part by the anti-Unruh effect, and the anti-Unruh effect could only appear for a finite range of acceleration when the interaction time scale is approximately shorter than the reciprocal of the energy gap in two dimensional spacetime. The limit case of zero acceleration is also investigated, which gives an analytical interpretation for the increase or recovery of entanglement.

This study reveals that the onset of tropical Asian summer monsoon (TASM) experienced a pronounced interdecadal delay (about one week) after the late‐2000s. Both the large‐scale seasonal transition reflected by EOF analysis and the monsoon onset dates defined by local rainfall exhibited a clear interdecadal change. Correspondingly, there appears reduced rainfall and low‐level easterly anomalies over tropical Asia in May, indicating that the monsoonal westerly winds and convective activities cannot be stably established. Further analysis suggests that the SST warming in the equatorial western Indian Ocean serves as a possible driver of the delayed TASM onset. The warm SST anomalies trigger a Kelvin wave‐like response to the east, inducing anticyclonic circulation and easterly anomalies over tropical Asia, which hinder moisture transport and reduce rainfall. The reduced rainfall further strengthens anomalous easterly winds, thereby favoring the delayed onset of the summer monsoon.

Tropical atmospheric convection generated by the El Niño–Southern Oscillation (ENSO) plays a crucial role in affecting the western Pacific pattern (WP) in the boreal winter by triggering an atmospheric teleconnection. Here we show from analysis of observations and model simulations that the Atlantic Multidecadal Oscillation (AMO) asymmetrically modulates the relationship between ENSO and WP. We find a significant modulatory effect of AMO on the relationship between wintertime El Niño and WP. A robust El Niño−WP relation can be attributed to the negative AMO phase (−AMO), yet a weak relationship during the positive AMO phase (+AMO). In contrast, the relationship between La Niña and WP is independent of AMO modulation. Furthermore, during the −AMO period, stronger El Niño amplitudes lead to stronger atmospheric convection anomalies over the tropical western North Pacific, which excites stronger atmospheric teleconnection and thus has a more significant effect on WP than during the +AMO period. Plain Language Summary The western Pacific pattern (WP) is one of the most crucial teleconnection patterns in boreal winter over the Northern Hemisphere, which exerts substantial impacts on weather and climate in Eurasia and North America. El Niño–Southern Oscillation (ENSO) is the most prominent air‐sea coupling system in the tropics, considered to exert great impacts on the WP via triggering atmospheric teleconnection. In this study, we revealed that the Atlantic Multidecadal Oscillation (AMO) has a significant asymmetrical modulation on the relation between the ENSO and WP. In particular, a significant El Niño‒WP connection only occurs in the negative AMO phase (‒AMO). Physical mechanisms of the modulation effects of AMO on the ENSO–WP relationship are further analyzed. The results suggest that stronger El Niño amplitude during the −AMO phase leads to larger atmospheric convection anomalies in the equatorial central Pacific and tropical western North Pacific compared to those during the +AMO phase. As such, stronger atmospheric convection anomalies during El Niño events have a greater impact on WP events during the −AMO phase; however, for La Niña events, there is no significant impact on WP events during the −AMO phase. Results obtained in this study may help to improve our understanding of the WP variability. Key Points The connection between El Niño–Southern Oscillation (ENSO) and the western Pacific pattern (WP) varies markedly in different Atlantic Multidecadal Oscillation (AMO) phases A robust connection between ENSO and the WP in the boreal winter can only be observed during the negative AMO phase The AMO influences the ENSO‐WP relationship via modulating the ENSO amplitude and the associated change in atmospheric convection

In this paper, we review some methods that have tried to solve the information loss problem. In particular, we revisit the solution based on Hawking radiation as tunneling and provide a detailed statistical interpretation of the black hole entropy in terms of the quantum tunneling probability of Hawking radiation from the black hole. In addition, we show that black hole evaporation is governed by a time-dependent Schrödinger equation that sends pure states into pure states rather than into mixed states (Hawking had originally established that the final result would be mixed states). This is further confirmation of the fact that black hole evaporation is unitary.

Optical coherence tomography (OCT) is a noninvasive imaging technique that provides high-resolution images of superficial skin tissues and has become widely used for diagnosing various skin disorders. Assessing laser-induced skin tissue damage is essential for understanding the healing mechanisms and optimizing treatment strategies. However, effectively quantifying skin damage and its correlation with laser dosage and recovery time poses a challenge. In this study, we established a laser-induced skin injury model in mice, utilizing 1 μ m–2 μ m laser wavelengths. We obtained SS-OCT images of the injury site under different laser doses and recovery times. To enhance image clarity, we applied noise reduction using the BM3D algorithm. We employed an improved UNet network model that incorporates SimAM and PSA modules, forming three attention mechanisms: TandemAT-UNet, ParallelAT-UNet, and NestedAT-UNet. These models were used to segment the damaged skin regions, followed by a 3D reconstruction method to quantitatively evaluate the volume of skin damage while analyzing changes about laser dose and recovery time.The BM3D algorithm effectively suppressed high-noise components, significantly improving image clarity. Among the three models, ParallelAT-UNet exhibited the best segmentation performance, achieving a Dice coefficient of 0.9364, mean Pixel Accuracy (mPA) of 92.67%, mean Intersection over Union (mIoU) of 96.31%, and an accuracy of 99.39%. Quantitative analysis revealed that laser doses between 25.0   J/cm 2 and 36.5   J/cm 2 caused minimal changes in skin damage volume, while doses ranging from 44.2   J/cm 2 to 74.4   J/cm 2 resulted in significant changes, which varied according to both the dose and recovery time. All groups showed signs of healing by 14 days post-laser treatment, with damage volumes smaller than the initial values. This study presents an efficient and reliable method for the quantitative assessment of laser-induced skin damage using OCT imaging. The findings demonstrate a strong relationship between laser dosage, recovery time, and skin damage, highlighting potential applications for noninvasive diagnosis and treatment monitoring using OCT.

The PM2.5 (fine particulate matter with diameter ≤2.5 μm) concentration anomalies over the North China Plain (NCP) in early and late winter sometimes show a subseasonal reversal, which brings a great challenge for precise control of air pollution, and mechanisms are not well understood. This paper reveals the key role of the Barents Sea sea‐ice in this reversal. In early winter, a negative Scandinavian‐like pattern causes an anticyclonic anomaly over Northeast Asia and thus leads to the positive PM2.5 concentration anomaly over the NCP. In addition, anomalous warm advection associated with the positive North Atlantic Oscillation‐like pattern accelerates winter sea‐ice loss in the Barents Sea, especially in late winter, which increases the surface turbulent heating flux. These heating causes a negative Polar/Eurasian‐like pattern that induces a cyclonic anomaly over Northeast Asia and eventually leads to a negative PM2.5 concentration anomaly over the NCP in late winter. Vice versa. Plain Language Summary In this study, we find that there is a significant seesaw pattern of PM2.5 concentration anomalies over the North China Plain (NCP) in early and late winter. Further results reveal that variations in Barents Sea sea‐ice play a crucial role. More specifically, a negative (positive) Scandinavian‐like pattern in early winter tends to induce an anticyclonic (a cyclonic) anomaly over Northeast Asia. This anticyclonic (cyclonic) anomaly leads to a higher (lower) PM2.5 concentration anomaly over the NCP in early winter. In addition, a North Atlantic Oscillation‐related warm (cold) temperature advection promotes (inhibits) the sea‐ice loss in the Barents Sea, especially in late winter. The Barents Sea‐ice loss (increment) in late winter tends to heat (cool) the lower‐level atmosphere and thus triggers an anticyclonic (a cyclonic) response in the upper troposphere there. The anticyclonic (cyclonic) response in the Barents Sea region as a part of the negative (positive) Polar/Eurasian‐like pattern induces a cyclonic (an anticyclonic) anomaly over Northeast Asia, which leads to a lower (higher) PM2.5 concentration anomaly over the NCP in late winter. These findings could be of great value for the subseasonal predictions of PM2.5 concentrations over the NCP in winter. Key Points PM2.5 concentration anomaly over the North China Plain shows an visibly subseasonal reversal in early and late winter on interannual scale The Scandinavia‐like pattern and Polar/Eurasian‐like pattern are responsible for the seesaw pattern of PM2.5 concentration anomalies The sea‐ice variations in the Barents Sea play a key role in modulating such atmospheric circulations

Southwest China experienced a severe drought during winter 2022–spring 2023. This drought mainly struck Yunnan Province and surrounding regions (21°–30° N, 97°–106° E), with precipitation deficit lasting for about 8 months from Oct 2022 to May 2023. The area-mean precipitation and surface soil moisture in the study region during the drought were both the lowest recorded for the same period since 1950. The Standardized Precipitation Evapotranspiration Index (SPEI) also reached its lowest level since 1950 at −2.76. Quantitative analysis shows that precipitation deficit and potential evapotranspiration (PET) increase contributed 71.36%, and 28.64% to the SPEI, respectively. Of the raw contribution of PET, 7.05% can in turn be attributed to the changes in precipitation. Using data from the CMIP6 Detection and Attribution Model Intercomparison Project (DAMIP), we found that anthropogenic forcing increased the likelihood of a PET anomaly such as the one during the drought by about 133 times, with a fraction of attributable risk (FAR) of 0.99 [0.98, 1.00]. For the precipitation anomaly, we obtained a FAR of 0.26 [−1.12, 0.70], suggesting that anthropogenic forcings may have little impact. The extreme drought also increased the risk of fires, with the Fire Weather Index reaching its second-highest value since 1950 and abnormally high burned areas observed by satellites.

Extreme climate events have increasingly threatened global terrestrial ecosystems in recent decades. In spring 2023, Southwest China (SWC) experienced unprecedented heatwaves and droughts. Using multiple satellite-based datasets, we found that these events led to the most significant declines in gross primary productivity (GPP) and the enhanced vegetation index (EVI) for the past two decades, with lagged effects persisting until August in the drought-affected area. Unlike the widespread and persistent drought of 2010, the record-breaking heatwaves in April and May 2023 sustained and intensified the drought stress. Elevated temperatures and suppressed precipitation, driven by anomalous atmospheric circulations, exacerbated the soil moisture (SM) shortages and increased the atmospheric vapor pressure deficit (VPD), restricting water availability and carbon uptake for vegetation photosynthesis. Our findings reveal that, during the 2023 extreme event in SWC, the decreases in forest productivity were primarily driven by low SM anomalies, while the decreases in the grassland and cropland productivity mainly resulted from abnormally high VPDs. This study highlights the combined effects of low SM and high VPD anomalies caused by a compound heatwave–drought event on vegetation growth in SWC and provides valuable insights for future assessments of regional extreme climate events on vegetation growth.