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The glaciers in southeastern Tibet Plateau (SETP) influenced by oceanic climate are sensitive to global warming, and there remains a notable deficiency in accurate multitemporal change analyses of these glaciers. We conduct glacier inventories in the Yigong Zangbo River Basin (YZRB) in SETP for the years 1988, 2015, and 2023 utilizing Landsat and Sentinel-2 imagery, and analyze the glacier spatiotemporal variation incorporating the existing glacier inventory data. Since the 1970s until 2023, the glaciers significantly retreated at a rate of 0.76 ± 0.11%·a−1, with the area decreasing from 2583.09 ± 88.80 km2 to 1635.89 ± 71.74 km2, and the ice volume reducing from 221.7017 ± 7.9618 km3 to 152.7429 ± 6.1747 km3. The most significant retreat occurred in glaciers smaller than 1 km2. Additionally, glaciers on southern aspects retreated slower than the northern counterparts. The glaciers in the western YZRB witnessed a significantly greater shrinkage rate than those in the eastern section, with the most pronounced changes occurring in Aso Longbu River Basin. Furthermore, severe glacier mass deficits were observed from 2000 to 2019, averaging a loss rate of 0.57 ± 0.06 m w.e. a−1. The continuous rise in air temperature has primarily induced a general widespread glacier change in the YZRB. However, diverse topography led to spatial variability in glacier changes with discrepancies as large as several times. The features of individual glaciers, such as glacier size, debris cover, and the development of ice-contact glacial lakes enhanced the local complexity of glacier change and elusive response behaviors to climate warming led by the different topographic conditions. [ABSTRACT FROM AUTHOR]

An editorial focuses on the potential for increased catastrophic flow events in alpine glacier zones due to climate change, using the Chamoli rock-ice avalanche as a case study. It highlights the severe instability of alpine slopes as a consequence of glacial retreat and warming temperatures, suggesting that such events are likely to become more frequent and severe. It emphasizes the need for ongoing monitoring and assessment of these high-risk areas to mitigate future disasters.

Under global warming, many glaciers worldwide are receding. However, recent studies have suggested the extension of the Karakoram Anomaly, a region of anomalous glacier mass gain, into the western Kunlun and eastern Pamir mountains. However, the eastern limit of this anomaly in the Kunlun Mountains is unclear. This study, using changes in glacier area and surface elevation, estimates the eastern limit of the Kunlun-Pamir-Karakoram anomaly at ~85°E. Over the past 50 years, glaciers west of 85°E in the Kunlun Mountains decreased in area from 8401 to 7945 km2 at a rate of −0.12 ± 0.07% a−1, showed a reduction in the rate of retreat through time and have recently gained mass, with surface elevation changes of 0.15 ± 0.35 m a−1 over the period of 2000–2013. Glaciers east of 85°E have experienced greater rates of area change (−61 ± 12 km2 and −0.43 ± 0.13% a−1) over the past 50 years, accelerated area loss in recent years and elevation change rate of −0.51 ± 0.18 m a−1 between 2000 and 2013. These patterns of elevation and area change are consistent with regional increases in summer temperature in the eastern Kunlun Mountains and slight cooling in the western Kunlun Mountains. [ABSTRACT FROM AUTHOR]

In the context of global warming, glaciers in the Asian High Mountains (AHMs) are shrinking at an accelerating rate. Projecting their future change is helpful for understanding the hydrological and climatic effects related to glacier retreat. Here, we projected glacier change in the AHMs from 1979 to 2100 under shared socioeconomic pathway (SSP) scenarios from the perspective of temperature, equilibrium-line altitude (ELA), and accumulation area. The annual mean temperature in the AHMs increased by 1.26°C from 1979 to 2014, corresponding to an increase of 210 m in the mean ELA and a decrease of 1.7×104 km2 in the glacier accumulation area. Under the SSP2-4.5 (SSP5-8.5) scenario, the annual mean temperature in the AHMs would increase by 2.84°C (3.38°C) in 2040–2060 relative to that in 1850–1900, leading to the mean ELA reaching an elevation of 5661 m (5777 m). The accumulation area in the AHMs decreased by 46.3% from 1995 to 2014 and was projected to decrease by 60.1% in 2040–2060. Moreover, the annual mean temperature in the AHMs was projected to increase by 3.76°C (6.44°C) in 2080–2100 relative to that in 1850–1900, corresponding to the ELA reaching an elevation of 5821 m (6245 m) and the accumulation area decreasing to 1.8×104 km2 (0.5×104 km2). These data suggest that the conditions for glacier development will disappear in most of the AHMs, except for extreme high-altitude regions in the Tianshan, Pamir, and Himalaya Mountains. Under the SSP2-4.5 (SSP5-8.5) scenario, when the global mean temperature increases 1.5°C (2°C) above pre-industrial levels, the annual mean temperature will increase by 2.12°C (2.86°C) and the accumulation area will decrease by 15% (48%) in the AHMs compared with that in 1995–2015. Therefore, a 1.5°C increase in global warming would keep 40% more of the glacial accumulation area (1.5×104 km2) in the AHMs compared to a 2°C increase in global warming. [ABSTRACT FROM AUTHOR]

With global warming and rapid urbanization, urban agglomerations (UAs) over the Loess Plateau (LP) are suffering from various urban disasters. Urbanization has aggravated the decreasing trends of extreme precipitation in Taiyuan and Xi'an UAs and enhanced the increasing trends of extreme precipitation in Luoyang, Hohhot and Xining UAs during 1979–2018. Meanwhile, the number of light rain days decreases in almost all the cities, indicating the sensitivity of light rain days to urbanization. Climate change is a primary contributor to the change of urban precipitation during 1979–2000 in this region. But, the contribution of urbanization has been increasing gradually since 2000, and it further amplifies the influence of climate change. In terms of physical mechanisms, rapidly increasing surface temperatures and aerosol particles are closely related to urban precipitation. Our findings provide a systematic understanding of the urbanization effects on extreme precipitation over the LP, playing an important role in the mitigation of future urban disasters. [ABSTRACT FROM AUTHOR]

Grasslands cover 41.7% of China's land surface and distribute mainly in NW China. To project future change of grassland fires, it is essential to explore paleofire dynamics. However, comparatively little is known about the patterns and driving forces of grassland fires in NW China due to the scarcity of paleorecords. Here, we present Holocene sedimentary records of grassland fire and vegetation in westerly‐dominated Xinjiang (NW China) to examine fire‐fuel‐climate interactions. We find that grassland fire regime is fuel‐limited, consistent with other grasslands worldwide. We reveal that burning increased throughout the Holocene, due to increasing moisture, grass cover, fuel load, and temperature of spring fire season. The Holocene pattern of burning coincides with several other records nearby and a global‐scale grassland fire record. Our results are different from monsoonal China where fuel load is not a constraining factor and more (less) fires occurred during colder/drier (warmer/moister) periods in the Holocene. Plain Language Summary: Recently, catastrophic fires occurred frequently, such as California (2018), Amazon (2019), and Australia (2020), causing tremendous losses to natural resources, human/animal lives, and socioeconomic assets. The fire risks with considerable costs are projected to increase under global warming. To estimate the effects of forthcoming climatic fluctuations on fire activity for large‐scale fire‐prone ecosystems, we need sufficient long‐term information regarding the fire‐fuel‐climate interactions on various spatial‐temporal scales. Notably, widespread grasslands make up roughly 40.5% and 41.7% of the Earth's and China's land surface, respectively. However, Holocene fire dynamics across extensive grassland areas of NW China are not well understood, owing to the scarcity of paleofire records. Here, we provide Holocene sedimentary records of grassland fire and vegetation in Xinjiang of NW China to explore the linkages among fire, fuel, and climate during the Holocene. We suggest that climatic conditions of spring fire‐season and moisture availability are essential for driving the fire‐regime evolution. We find that intensified fire activity has been caused by increased flammability (fire‐season) and enhanced cumulative biomass (fuel‐load) along with increased humidity throughout the Holocene. More importantly, we critically need more grassland paleofire records to understand long‐perspective fire dynamics of interior China. Key Points: The study examines Holocene fire and vegetation records to explore fire‐fuel‐climate interactions in Bortala Basin of Xinjiang in NW ChinaGrassland fire regime is fuel‐limited and burning shows a gradually increasing trend over the last ca. 10,000 yearsRelative humidity and temperature of the spring fire season are the primary drivers of fire‐regime dynamics during the Holocene [ABSTRACT FROM AUTHOR]

Due to climate changes, most of the alpine glaciers have retreated dramatically during the past decades. Thus it is significant to predict the alpine glacier variability in the future for a better understanding of the impact of climate changes on water resource. In this paper, we perform the numerical simulation on Urumqi Glacier No.1 in the eastern Tianshan, central Asia (hereafter Glacier No.1 for short) by considering both the mass balance and ice flow. Given the shape of the Glacier No.1, the velocity of the glacier is obtained by solving a two-dimensional nonlinear Stokes equation and simulated result is in agreement with the observation. In order to predict the variability of Glacier No.1 in the next decades, a climatic scenario is constructed with a temperature rise rate as 0.17°C/10 a and precipitation as constant during the period of 2005-2070. The simulation shows that, the glacier terminus will retreat slowly and the glacier will thin dramatically before 2040, while after year 2040, the glacier terminus retreat will accelerate. This study confirms the increasing retreat rate of alpine glaciers under global warming. [ABSTRACT FROM AUTHOR]

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a decrease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ18O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change. [ABSTRACT FROM AUTHOR]

• Thermokarst landslides mainly occurred before 2016 and expanded since then. • Thermokarst landslides exhibited slow creep besides seasonal deformation. • The slope effect showed serious thermokarst landslides on shady slopes. Permafrost degradation under warming climate causes a variety of topographic separation and collapses on hillslopes, collectively known as thermokarst landslides, which seriously affects the stability of the permafrost environment. However, quantitative understanding of the formation and evolution of thermokarst landslides under warming conditions is still limited, thus easily ignoring their realistic vulnerability. Here, we combined the visual interpretation of high-resolution optical satellite images, interferometric synthetic aperture radar (InSAR) measurement, and wavelet analysis to demonstrate the spatiotemporal distribution and the creep characteristics of thermokarst landslides. A total of 385 thermokarst landslides were cataloged on central Tibetan Plateau from 2010 to 2020, and most failures occurred before 2016 and then expanded. The spatial distribution of thermokarst landslides was closely related to topography. The slope effect explained a higher occurrence of thermokarst landslides on shady slopes compared to sunny ones. Time-series InSAR also documented their deformation rates from −40 to 30 mm/year, with much higher rates on shady slopes. Coupled with permafrost stratification, wavelet analysis and time-series displacement fitting traced the stratification characteristics of thermokarst landslides. The freeze–thaw cycle of the active layer results in seasonal frost heave and thaw subsidence, and when combined with the underlying permafrost degradation can form prominent thermokarst landslides. The results quantify the kinematic characteristics of thermokarst landslides and their obvious slope effects, providing a comprehensive understanding of their intrinsic development. [ABSTRACT FROM AUTHOR]

Abstract: The dustiness on the remote Tibetan Plateau and its trend within the ongoing global warming perspective are not well understood. In this study, we present the detailed dust history from 1850 to 2004 AD on an annual timescale from a shallow ice core from Tanggula, central Tibetan Plateau. Two periods of strong dustiness, one at the end of the Little Ice Age (1860–1874) and the other during the period 1930–1954, occurred during low oxygen isotope stage, which is correlated with temperature on multi-year and decadal timescales. The extremely high level of dust flux between 1860 and 1874 was unique – this level has not occurred again during the past century, and the 1930s'' dustiness was characterized more by strong wind and dust storms rather than drought, as shown by great grain size but low dust flux. We have used the composite analysis of modern meteorological data to study the possible dustiness mechanism and found that strengthened high-level westerlies over the Tibetan Plateau and intensified low pressure activities in the upward potential source regions, such as Tarim Basin, are the possible causes for high dust flux in Tanggula. Those results have revealed that although the dustiness on the Tibetan Plateau normally occurs in cold conditions, pronounced warming since the 1960s can change the dust pattern and strengthen the dustiness in this remote and high-altitude region, and can thus induce associated environmental issues by creating dustier conditions. [Copyright &y& Elsevier]