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China is a key region for understanding fire activity and the drivers of its variability under strict fire suppression policies. Here, we present a detailed fire occurrence dataset for China, the Wildfire Atlas of China (WFAC; 2005–2018), based on continuous monitoring from multiple satellites and calibrated against field observations. We find that wildfires across China mostly occur in the winter season from January to April and those fire occurrences generally show a decreasing trend after reaching a peak in 2007. Most wildfires (84%) occur in subtropical China, with two distinct clusters in its southwestern and southeastern parts. In southeastern China, wildfires are mainly promoted by low precipitation and high diurnal temperature ranges, the combination of which dries out plant tissue and fuel. In southwestern China, wildfires are mainly promoted by warm conditions that enhance evaporation from litter and dormant plant tissues. We further find a fire occurrence dipole between southwestern and southeastern China that is modulated by the El Niño-Southern Oscillation (ENSO). Fire activity in China and its associations with climate are not well quantified at a local scale. Here, the authors present a detailed fire occurrence dataset for China and find a dipole fire pattern between southwestern and southeastern China that is modulated by the El Niño-Southern Oscillation (ENSO).

The Earth’s three poles, the North Pole, South Pole, and Third Pole (i.e., the Tibetan Plateau and its surroundings), hold the largest amount of fresh water on Earth as glaciers, sea ice, and snow. They are sensitive to climate change. However, the linkages between climate variations of the three poles, particularly between the South Pole and Third Pole, remain largely unknown. The temperatures at 200 hPa over the three poles are the highest in the summer and are less affected by surface conditions, which could reflect large-scale dynamic linkages. Temperatures at 200 hPa peak the three poles during their respective hemispheric summer and exhibit in-phase variations on interdecadal timescales (10-100 years). The 200 hPa temperatures over the North Pole and South Pole were significantly correlated with the Brewer-Dobson circulation (BDC), which transports stratospheric ozone poleward, heating the air at 200 hPa. Tropopause warming over the Third Pole was found to enhance the poleward BDC, particularly to the South Pole, linking the Third Pole’s climate to the other two poles. Additionally, the Interdecadal Pacific Oscillation (IPO) also exhibits links with the 200 hPa temperatures of the three poles.

Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming. However, temperature reconstructions in humid southeastern China are scarce and particularly lack long-term data, limiting us to obtain a complete picture of regional temperature evolution. In this study, we present a well-verified reconstruction of winter-spring (January–April) minimum temperatures over southeastern China based on stable carbon isotopic (δ 13 C) records of tree rings from Taxus wallichiana var . mairei from 1860 to 2014. This reconstruction accounted for 56.4% of the total observed variance. Cold periods occurred during the 1860s–1910s and 1960s–1970s. Although temperatures have had an upward trend since the 1920s, most of the cold extremes were in recent decades. The El Niño-Southern Oscillation (ENSO) variance acted as a key modulator of regional winter-spring minimum temperature variability. However, teleconnections between them were a nonlinear process, i.e., a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.

Against the backdrop of global economic volatility, environmental pressures, and intensifying industry competition, tourism resilience has become a critical indicator for assessing the capacity of tourism systems to withstand external shocks and achieve sustainable development. As an important engine of high-quality economic growth, the digital economy provides new momentum for strengthening tourism economic resilience. Existing literature predominantly focuses on the direct impacts of the digital economy, with insufficient exploration of its mediating pathways and spatial effects. Based on panel data from 11 provinces in China’s Yangtze River Basin from 2011 to 2023, this study constructs comprehensive evaluation index systems for the digital economy and tourism economic resilience. A mediating effect model and a Spatial Durbin Model are employed to systematically examines the impact mechanisms and spatial spillover effects of the digital economy on tourism resilience. The results show that the digital economy significantly enhances tourism economic resilience, primarily by fostering openness and technological innovation. Heterogeneity analysis indicates that this effect is more pronounced in provinces located in the upper and lower reaches of the Yangtze River Basin. Spatial analysis further reveals a significant positive local effect, accompanied by a negative spillover—or ‘siphon’—effect on neighboring provinces. Building upon the verification of the fundamental relationship, this study further extends the theoretical analytical framework of tourism resilience from the dimensions of mechanism decomposition and spatial effects. It thereby offers new empirical evidence and policy insights for fostering regional tourism resilience in the era of the digital economy.

Understanding the interdecadal periodicity of large-scale seismic activities is critical for improving long-term earthquake forecasting, yet it remains constrained by the limited duration of instrumental records. Here we apply high-resolution spectral analysis to a millennia-long catalog of historical earthquakes in China, extending to 1831 BC. The most pronounced seismic activities occurred during the 1620–1630 s AD, a period that coincided with a major regime shift that preceded the collapse of the Chinese Ming Dynasty. High-resolution spectral analysis was performed on the historical dataset to identify robust ~ 10- and ~ 50-year periodicities in seismic frequency. The ~ 10-year periodicity exhibits a significant lagged correlation with solar (sunspot) activity, while the ~ 50-year periodicity aligns with multidecadal variability in solar irradiance, sea level fluctuations, and tropical sea surface temperatures (SSTs). We propose that enhanced solar irradiance modulates the mean state and variability of tropical Pacific climate modes, particularly the El Niño–Southern Oscillation (ENSO), which is associated with changes in inter-basin sea-level gradients and crustal stress regimes. These findings reveal a potential coupling between external solar forcing and internal climate variability in shaping seismic cyclicity at interdecadal scales, offering a novel framework for assessing long-term earthquake risks.

The El Niño/Southern Oscillation exhibits considerable natural variability on interdecadal to centennial timescales making it difficult to understand how climate change affects it. A reconstruction now shows there has been anomalously high activity in the late twentieth century, relative to the past seven centuries. This is suggestive of a response to global warming, and will provide constraints to improve climate models and projections. Predicting how the El Niño/Southern Oscillation (ENSO) will change with global warming is of enormous importance to society 1 , 2 , 3 , 4 . ENSO exhibits considerable natural variability at interdecadal–centennial timescales 5 . Instrumental records are too short to determine whether ENSO has changed 6 and existing reconstructions are often developed without adequate tropical records. Here we present a seven-century-long ENSO reconstruction based on 2,222 tree-ring chronologies from both the tropics and mid-latitudes in both hemispheres. The inclusion of tropical records enables us to achieve unprecedented accuracy, as attested by high correlations with equatorial Pacific corals 7 , 8 and coherent modulation of global teleconnections that are consistent with an independent Northern Hemisphere temperature reconstruction 9 . Our data indicate that ENSO activity in the late twentieth century was anomalously high over the past seven centuries, suggestive of a response to continuing global warming. Climate models disagree on the ENSO response to global warming 3 , 4 , suggesting that many models underestimate the sensitivity to radiative perturbations. Illustrating the radiative effect, our reconstruction reveals a robust ENSO response to large tropical eruptions, with anomalous cooling in the east-central tropical Pacific in the year of eruption, followed by anomalous warming one year after. Our observations provide crucial constraints for improving climate models and their future projections.

With high temporal resolution and accurate age control, tree-ring width is a good proxy for recording past climate variations from interannual to centennial time scales. The complex network method, widely used in analyses of modern meteorological observations, is an effective method to demonstrate synchronizations within climate events, thus revealing potential climate teleconnections. In this study, we tested to use the complex network in analyzing extremes recorded in time serials of tree-ring width in East Asia during the past 600 years. Our study indicates that this method is a valuable approach to reveal synchronizations in climate-sensitive tree-ring width records, though the ability of this method is dependent on the quality of the tree-ring data. Furthermore, our study shows stronger synchronizations in extremes of tree-ring width records during the CE 1850–1950 period in the Modern Warm Period than the CE 1450–1650 period in the Little Ice Age. A remarkable shift in synchronization types within the south part and the inland East Asia sites appears during the year CE 1850–1950. These changes in synchronizations suggest potential reorganizations in climate teleconnections, which is worthy being addressed in further studies with detrending and statistical significance testing methods involved.

Global warming has intensified extreme rainfall events and prolonged droughts, significantly impacting tree growth and wood formation. This study investigates the effects of late-summer precipitation variability on the intra-annual growth dynamics of Cunninghamia lanceolata and Cryptomeria fortunei in humid subtropical China. Microcores were collected from 12 trees at 7–10 days intervals between March and December from 2021 to 2023 in the Gushan Mountains. Typically, high temperatures and rainfall deficits in July induce cambial dormancy, while subsequent rainfall in August and September reactivates growth, resulting in a bimodal growth pattern. However, in 2022, an unprecedented drought (August–October rainfall 77% below average) shortened the growing season, causing an early cessation of growth and a rare unimodal growth pattern. In contrast, persistent rainfall in 2023 accelerated cell enlargement to 7 μm d - ¹ and significantly increased latewood intra-annual density fluctuations (L-IADFs). Notably, despite abundant late-summer rainfall in 2021, L-IADFs did not form, indicating a nonlinear and inconsistent relationship between rainfall and L-IADFs. These findings highlight the critical role of late-summer precipitation variability in shaping tree growth patterns and wood density in southeastern China. Given the expected increase in precipitation variability under climate change, regional forest ecosystems may become more vulnerable. This study provides valuable insights for forest management strategies to enhance resilience and mitigate climate-related risks.

The sensitivity of tree growth to precipitation regulates their responses to drought, and is a crucial metric for predicting ecosystem dynamics and vulnerability. Sensitivity may be changing with continuing climate change, yet a comprehensive assessment of its change is still lacking. We utilized tree ring measurements from 3,044 sites, climate data and CO2 concentrations obtained from monitoring stations, combined with dynamic global vegetation models to investigate spatiotemporal changes in the sensitivity over the past century. We observed an increasing sensitivity since around 1950. This increased sensitivity was particularly pronounced in arid biomes due to the combined effect of increased precipitation and elevated CO2. While elevated CO2 reduced the sensitivity of the humid regions, the intensified water pressure caused by decreased precipitation still increased the sensitivity. Our findings suggest an escalating vulnerability of tree growth to precipitation change, which may increase the risk of tree mortality under future intensified drought. Plain Language Summary The sensitivity of tree growth to precipitation strongly regulates global vegetation dynamics and their responses to climate change, yet changes in sensitivity remain poorly understood. Here, we defined a sensitivity of tree radial growth to precipitation, and found that most tree species showed an increased sensitivity in the second half of the 20th century. This increased sensitivity in arid biomes could be attributed to increasing precipitation, while the increased sensitivity in humid biomes was caused by decreasing precipitation. Although elevated atmospheric CO2 have generally increased sensitivity in arid biomes and decreased it in humid biomes, these contrasting influences were ultimately overshadowed by changes in precipitation, resulting in an overall increased sensitivity across both arid and humid biomes. Key Points The sensitivity of tree growth to precipitation is increasing since around 1950, both at the arid and humid biomes This increased sensitivity is particularly pronounced in arid biomes due to the combined effect of increased precipitation and elevated CO2 Although elevated CO2 reduce the sensitivity in humid biomes, the decreased precipitation still lead to an increased sensitivity

Rapid warming has been observed in the high-altitude areas around the globe, but the implications on moisture change are not fully understood. Here we use tree-rings to reveal common moisture change on the southeastern Tibetan Plateau (TP) during the past five centuries, and show that regional moisture change in late spring to early summer (April–June) is closely related to large-scale temperature anomaly over the TP, with increased moisture coincident with periods of high temperature. The most recent pluvial during the 1990s–2000s is likely the wettest for the past five centuries, which coincides with the warmest period on the TP during the past millennium. Dynamic analysis reveals that vertical air convection is enhanced in response to anomalous TP surface warming, leading to an increase in lower-tropospheric humidity and effective precipitation over the southeastern TP. The coherent warm-wet relationship identified in both tree-rings and dynamic analysis implies a generally wetter condition on the southeastern TP under future warming.