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Mio‐Pliocene sedimentary archives of the East Asian summer monsoon (EASM) in NE Tibet record a monotonic response to orbital forcing, dominated by eccentricity. By contrast, Pleistocene archives display a more stochastic response that varies regionally and temporally. When and why this response changed is poorly understood. Here, we present a new high‐resolution Rb/Sr ratio data set of EASM intensity from the Sanmenxia Basin, North China, that spans the Plio‐Pleistocene transition. Our results indicate decreased monsoonal rainfall in the late Pliocene, dated at 2.75–2.6 Ma, associated with an intensified response to obliquity and enhanced climate stochasticity. This transition is attributed to the increase of Northern Hemisphere ice volume. Quaternary monsoons display a sensitivity unique to the modern icehouse with large bipolar ice sheets, while pre‐Quaternary monsoons were solely impacted by Antarctic ice sheet dynamics on orbital time‐scales. Plain Language Summary: The late Pliocene‐early Pleistocene transition (LP/EP) is a period of global cooling and the intensification of Northern Hemisphere glaciation. Yet, the evolution of the East Asian summer monsoon (EASM) during this time remains a topic of ongoing discussion and debate. Here we present high‐resolution paleoclimate data from a record of lake sediments across the Pliocene‐Pleistocene transition period. We show that there was a reorganization of the East Asian monsoon system 2.75–2.6 million years ago, associated with an increase in climate forcing caused by cyclic changes in Earth's tilt and in climate stochasticity. This transition is attributed to the appearance of new high‐latitude forcing mechanisms on monsoon intensity caused by the growth of ice sheets in the Northern Hemisphere. Key Points: Cyclic patterns in East Asian summer monsoonal intensity during the Pliocene were mainly driven by Antarctic ice sheet variationsA major reorganization of the East Asian climate system occurred at 2.75–2.6 Ma in response to Northern Hemisphere glaciationQuaternary East Asian summer monsoon on orbital scales displays a sensitivity that is unique to the modern icehouse with bipolar ice sheets [ABSTRACT FROM AUTHOR]

Since the Quaternary, the alternate climate of dry and wet, cold and warm, and the emergence of glacial and interglacial periods have led to great changes in the global environment and climate. As an event closely related to cold climate, cryogenic soil has important reference significance for the study of climate change in a certain region and time period. The research on cryogenic soils mainly focuses on the following three aspects: particle size composition, surface morphology and mineral composition. Through the study of the relevant literature, we find that the correlation coefficient of particle size composition before and after freeze-thaw is used to determine the cause of cryogenic weathering. Due to the singleness of judgment conditions, the result is difficult to be convincing; It is difficult to prove the microscopic morphology of the cause of cryogenic weathering from a single mineral of quartz. Therefore, it is necessary to start with more types of primary minerals, and analyze the differences in the particle shape and microscopic surface morphology of different types of primary minerals during the cryogenic weathering process. And on this basis, the typical mineral morphology of the cause of cryogenic weathering is comprehensively judged; Freeze-thaw has little effect on the mineral composition of the soil, but has a greater impact on the size of the mineral particles, and this size change corresponds to the phenomenon of particles silt-fication. The mineral composition also controls the geochemical composition, and the insignificance of the mineral-chemical composition in the process of cryogenic silt-fication increases the difficulty of judging the cause of cryogenic weathering. [ABSTRACT FROM AUTHOR]

As one of the best indicators of the periglacial environment, ice-wedge polygons (IWPs) are important for arctic landscapes, hydrology, engineering, and ecosystems. Thus, a better understanding of the spatiotemporal dynamics and evolution of IWPs is key to evaluating the hydrothermal state and carbon budgets of the arctic permafrost environment. In this paper, the dynamics of ground surface deformation (GSD) in IWP zones (2018–2019) and their influencing factors over the last 20 years in Saskylakh, northwestern Yakutia, Russia were investigated using the Interferometric Synthetic Aperture Radar (InSAR) and Google Earth Engine (GEE). The results show an annual ground surface deformation rate (AGSDR) in Saskylakh at −49.73 to 45.97 mm/a during the period from 1 June 2018 to 3 May 2019. All the selected GSD regions indicate that the relationship between GSD and land surface temperature (LST) is positive (upheaving) for regions with larger AGSDR, and negative (subsidence) for regions with lower AGSDR. The most drastic deformation was observed at the Aeroport regions with GSDs rates of −37.06 mm/a at tower and 35.45 mm/a at runway. The GSDs are negatively correlated with the LST of most low-centered polygons (LCPs) and high-centered polygons (HCPs). Specifically, the higher the vegetation cover, the higher the LST and the thicker the active layer. An evident permafrost degradation has been observed in Saskylakh as reflected in higher ground temperatures, lusher vegetation, greater active layer thickness, and fluctuant numbers and areal extents of thermokarst lakes and ponds. [ABSTRACT FROM AUTHOR]

The latest Paleocene to early Eocene was an interval of globally warm climate. However, the driving mechanisms regulating climate across this interval remain unclear due to the paucity of well-dated and stratigraphically continuous records from terrestrial basins. In this study, we present a continuous ∼430-m lacustrine core record from the QY-1 borehole spanning the late Paleocene-Early Eocene in the Subei Basin, East China. This unique record can be used to better elucidate the response of terrestrial sedimentation to astronomically forced climate change. A 4.54 Myr long astronomical time scale spanning 57.1 to 52.56 Ma is constructed for the second member of the Funing Formation (E f 2) based on magnetostratigraphy and cyclostratigraphy. Low-latitude summer insolation via eccentricity modulation of precession controlled paleolake evolution in the basin during the studied interval. At the same time, we show that the climate system during this greenhouse state was sensitive enough to respond to the small changes in insolation associated with 200-kyr eccentricity cycles. Evidence from gamma ray data suggests that the climate in the Subei Basin changed from warm and humid to arid at ∼54.1 Ma. • Establish an ATS with magnetostratigraphy and cyclostratigraphy for E f 2 in Subei Basin, East China. • A record of astronomically forced climate changes in the late Paleocene to early Eocene terrestrial succession in the Subei Basin was conformed. • The climate system during this greenhouse state was sensitive enough to respond to the small changes in insolation associated with 200-kyr eccentricity cycles. [ABSTRACT FROM AUTHOR]

The changing position of the northern boundary of the East Asian summer monsoon (EASM) on different timescales is important for a better understanding of future environmental changes at the edge of this monsoon's influence. Here, we have reconstructed climate changes in the central Hexi Corridor, located at the monsoon-westerlies transition zone of western China, over the past 13.3 ka. Our element data from a loess record suggest a wetting trend through the Holocene, which is different from the climate pattern observed in areas influenced by the monsoon, but consistent with sites influenced by westerlies. Comparisons indicate that the average location of EASM northern boundary in northwestern China during the early to middle Holocene was ∼300 km further northwest than today. Our Zr/Rb and grain size abundance data suggest a significant 500-year periodicity in the intensity of the East Asian Winter Monsoon (EAWM), which most likely originated from AO/NAO changes linked to solar output cycles. • A persistent wetting trend in the central Hexi Corridor through the Holocene was observed. • The EASM northern boundary during the early to middle Holocene was ∼300 km further northwest than today. • A significant 500-year periodicity of the EAWM was most likely originated from solar output-related AO/NAO changes. [ABSTRACT FROM AUTHOR]

Carbon footprint (CF) and inequality reductions were two of the most important sustainable development goals. However, there was a lack of understanding of the latest equality of carbon footprint across regions. Based on the multi-regional input-output table and the China Family Panel Studies survey data of 17 provinces, this paper examined the evolution of carbon footprint and inequality in China. The results showed a stark disparity between regions and a declined inequality in the last few years. Specifically, the CF per capita in northern provinces (Liaoning, Shanxi, Heilongjiang, Shandong and Shaanxi) exceeded the average level in 2017. From 2015 to 2017, the carbon inequality showed a downward trend, with a national CF-Gini coefficient decrease from 0.31 to 0.28. Meanwhile, the gap between CF per capita in urban areas and rural areas was declining, with a growth rate at 18% and 32% from 2015 to 2017, respectively. In addition, CF per capita from various consumption categories indicated that household equipment and daily necessities, residential, transportation and communication were the three most important sources, with a downward trend from 2015 to 2017. This study would provide policymakers with deep insights into policies to achieve just transition. [ABSTRACT FROM AUTHOR]