Global and Planetary Change最新文献

{"title":"Lake energy balance response to 21st century warming in the tropical high Andes","authors":"Jarunetr (Nadia) Sae-Lim ,&nbsp;Bronwen L. Konecky ,&nbsp;Carrie Morrill ,&nbsp;Neal Michelutti ,&nbsp;Christopher Grooms ,&nbsp;John P. Smol","doi":"10.1016/j.gloplacha.2025.104741","DOIUrl":"10.1016/j.gloplacha.2025.104741","url":null,"abstract":"<div><div>The response of Andean high-alpine lakes (&gt;4000 m above sea level) to atmospheric warming is poorly understood, in part due to a lack of long-term limnological and meteorological observations. Here, we use in situ observations, reanalysis data, satellite-derived data, and climate modeling output data paired with a one-dimensional lake energy balance model to investigate the response of lake thermal properties to observed and projected 21st century warming in the tropical high Andes of Peru. The lake model configuration is based on Lake Sibinacocha (13.86°S, 71.02°W, 4860 m a.s.l.), the largest high-alpine lake in the Andes and one of the few such lakes with temperature observations sufficient for model calibration. Relationships between recent air and lake temperature changes were investigated using the model forced with 21st-century ERA5-Land climate reanalysis data, CERES satellite-based observations, and future relationships were investigated using two CMIP6 future climate scenarios with CESM2 (SSP2–4.5 and SSP5–8.5). Results show that Sibinacocha whole-lake average temperature stayed relatively consistent between 2000 and 2023 due to high interannual variability. Lake Sibinacocha temperatures also display interannual variability that aligns with air temperature variations, suggesting that broad climatic teleconnections that affect Andean air temperatures also influence lake temperature and stratification. Under the SSP2–4.5 and SSP5–8.5 scenarios, the model indicates an acceleration of Lake Sibinacocha's whole-lake warming rate. By 2091–2100, Lake Sibinacocha is projected to increase 2.5 °C to 5.9 °C. Lake Sibinacocha is projected to warm unevenly, with greater warming in the top 20 m and austral spring, contributing to increased weak stratification in spring. Lake Sibinacocha is anticipated to respond more slowly to warming simply due to its large size. Therefore, our results should be considered a conservative end-member for other lakes in the tropical high Andes, which, due to their shallower sizes, will likely respond more quickly to atmospheric warming.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"248 ","pages":"Article 104741"},"PeriodicalIF":4.0,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Palaeoenvironmental evolution of the Northeastern Tibetan Plateau and its response to global temperature change during the Late Miocene: Geochemical and clay mineralogical evidence from the Jianzha Basin","authors":"Peng Jia ,&nbsp;Chaofeng Fu ,&nbsp;Yougui Song ,&nbsp;Jinhua Du ,&nbsp;Jun Zuo ,&nbsp;Saimaiti Akemu ,&nbsp;Beibei Zhang","doi":"10.1016/j.gloplacha.2025.104748","DOIUrl":"10.1016/j.gloplacha.2025.104748","url":null,"abstract":"<div><div>Aeolian deposits on the northeastern Tibetan Plateau (NETP) are valuable archives of the interaction between plateau uplift and climate change. We used the clay mineral assemblages and geochemistry of aeolian red clay in the Jianzha Basin, on the NETP, to reconstruct its paleoenvironmental evolution during the Late Miocene. We compared these data with those for surrounding basins and with global temperature changes sheds light on the relationship between regional tectonic-climatic processes and global changes on the NETP. Geochemical proxies of provenance change (Th/Sc, Zr/Sc, Eu/Eu*, La_N/Yb_N, and Zr/Cr) indicate a significant tectonic uplift event at ∼8.5 Ma on the NETP. Chemical weathering proxies (Rb/Sr, Li/Sr, and Ba/Sr) of bulk samples may be affected by sedimentary sorting. Hence, we used clay mineral (It = illite, Ch = chlorite, I/S = illite/smectite mixed layers, and Kao = kaolinite) and their assemblages ([S + I/S + Kao]/(It + Ch), (S + I/S)/(It + Ch), and (S + I/S)/It) to show that the climate of the Jianzha Basin tended towards aridity before ∼8.5 Ma and after ∼7.2 Ma. Conversely, during ∼8.5–7.2 Ma, the relatively humid environment in the Jianzha Basin was affected by both tectonic uplift and the intensification of the East Asian summer monsoon precipitation. Our study suggests that global temperature change controlled the climate of the NETP during the Late Miocene, and regional tectonism reinforcing this effect as a secondary controlling factors.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"248 ","pages":"Article 104748"},"PeriodicalIF":4.0,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increased in local precipitation weakenes long-term responses of soil carbon and nitrogen to climate change: Insights from a 37-year experiment","authors":"Yi Zhou ,&nbsp;Shenghua Chang ,&nbsp;Xiaojuan Huang ,&nbsp;Wenjun Wang ,&nbsp;Fujiang Hou ,&nbsp;Yanrong Wang ,&nbsp;Zhibiao Nan","doi":"10.1016/j.gloplacha.2025.104745","DOIUrl":"10.1016/j.gloplacha.2025.104745","url":null,"abstract":"<div><div>Soil ecological stoichiometry play vital roles in regulating structure and function of grassland ecosystems. However, the long-term dynamics of soil nutrient elements and their underlying driving mechanisms remain poorly understood, particularly in the context of changing precipitation patterns. Here, we conducted a long-term experiment to assess temporal-spatial dynamics and mechanisms of soil ecological stoichiometry along the precipitation gradient. Over the past 37 years, our results indicated a significant overall increase in soil organic carbon (SOC) and total nitrogen (STN) contents, accompanied by a decrease in soil total phosphorus (STP) content across the three sites. The sensitivity of SOC, STN, C:P, and N:P to climate change decreased significantly as local precipitation increased, while the sensitivity of SOC, STN, and C:N to local precipitation declined significantly over time. From north to south, STP content increased on average by 1.03 %, 1.16 % and 1.68 % in 1985, 2002 and 2022, respectively. Additionally, the coupling strength of SOC, STN and STP decreased with increasing local precipitation from 1985 to 2002. Furthermore, the interaction between climate and soil properties explained 18 % and 22 % of the variation in temporal stability and contents of SOC, STN and STP, climate was the most critical factor affecting spatial stability of SOC, STN and STP. Among them, average precipitation, plant phylogenetic diversity and soil moisture were key indicators of temporal-spatial variability in soil C:N:P stoichiometry. Our findings provide an overview of biogeographical nutrient cycles under different temporal and spatial contexts, which is critical for grassland management and conservation in future global change scenarios.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104745"},"PeriodicalIF":4.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic interactions between Fe, Mn, S and C cycles in the Okinawa Trough seep sediments","authors":"Cuiling Xu ,&nbsp;Qing Li ,&nbsp;Taiheng Lv ,&nbsp;Zhilei Sun ,&nbsp;Ang Li ,&nbsp;Ye Chen ,&nbsp;Xilin Zhang ,&nbsp;Feng Cai ,&nbsp;Nengyou Wu","doi":"10.1016/j.gloplacha.2025.104736","DOIUrl":"10.1016/j.gloplacha.2025.104736","url":null,"abstract":"<div><div>The semi-enclosed Okinawa Trough hosts hydrothermal vents and cold seep systems. The authigenic carbonate formation in the Okinawa Trough is thought to be associated with the anaerobic oxidation of methane (AOM) driven by Fe/Mn oxide reduction due to hydrothermal metal supply. However, in seep sediments near hydrothermal vents, Fe, Mn, S and C cycles and their diagenetic interactions are disconnected. Herein, a comprehensive suite of pore water solute concentrations and isotope ratios of four gravity cores (GC02, GC04, GC05, GC07) and three drilling cores (QZ02-C1, QZ03, QZ04) were analyzed to examine the diagenetic processes in the Okinawa Trough seep sediments. The accumulation of total dissolved Fe (DFe) and total dissolved Mn (DMn) in pore water suggested that metal oxide reduction occurred commonly in the sediments. In the Manganous zones, dissimilatory Mn reduction generally increased closer to the hydrothermal field, indicating that hydrothermal Mn supplies promoted organic matter mineralization. In the Sulfidic zones of Sites QZ03 and QZ04, the DMn and HS⁻ contents reached peaks synchronously revealed inorganic Mn reduction coupled with HS⁻ oxidation. At 21–25 m below the seafloor (mbsf) of Site QZ02-C1 and at 0.5 and 1.1 mbsf of Site GC02, the accumulation of DFe in pore water, accompanied by the negative offset in δ¹³C_DIC, suggested Fe-AOM or a Fe-derived cryptic S cycle in the Sulfidic zones. In the Methanic zone of Site QZ03, high Mg²⁺ consumption with DFe and DMn enrichment and effectively neutralized pore water implied that Fe/Mn oxide reduction could promote dolomite and siderite precipitation. However, the upward migration of deep CO₂ prevented precipitation. The results revealed that hydrothermal metal is crucial in the diagenetic processes in methane seep sediments, e.g., it promotes organic matter degradation, enhances benthic filtering of methane by promoting Fe-rich carbonate precipitation, and alters the geochemical cycles of Mg²⁺, HS⁻, total alkalinity, pH, dissolved inorganic carbon, and CH₄. Overall, this research helps understand Fe, Mn, S and C cycles in back-arc basins and can be important for the CH₄-rich but <span><math><mi>S</mi><msubsup><mi>O</mi><mn>4</mn><mrow><mn>2</mn><mo>−</mo></mrow></msubsup></math></span>-depleted Archaean ocean.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"248 ","pages":"Article 104736"},"PeriodicalIF":4.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dust deposition and iron cycling in the tropical western North Pacific based on thorium supply","authors":"Xin Wang ,&nbsp;Xinru Zhang ,&nbsp;Weifeng Yang ,&nbsp;Dalin Shi ,&nbsp;Min Chen ,&nbsp;Hua Cheng ,&nbsp;Qiaoyun Lin ,&nbsp;Pinghe Cai ,&nbsp;Yihua Cai","doi":"10.1016/j.gloplacha.2025.104740","DOIUrl":"10.1016/j.gloplacha.2025.104740","url":null,"abstract":"<div><div>Dissolved ²³²Th and biologically-essential micronutrients, such as Fe, are simultaneously supplied to the open ocean mainly through the dissolution of dust aerosols. Both dust and associated Fe deposition fluxes are therefore able to be estimated by the long-lived Th isotopes (²³⁰Th and ²³²Th) in seawater in combination with the concentration and solubility of Th and Fe in aerosols. The vertical distribution of dissolved ²³⁰Th and ²³²Th in water columns and the solubilities of Fe and Th in aerosols were examined in the tropical western North Pacific during the GEOTRACES-China GP09 cruise. The solubilities of Fe ad Th in aerosols were 14.38 ± 1.02 % and 12.22 ± 2.46 %, respectively, giving a solubility ratio of S_{<em>Fe/Th</em>} of 1.24 ± 0.34. Estimated dust deposition fluxes integrated over the upper 500 m of the water column ranged from 0.58 to 2.35 g m⁻² yr⁻¹ based on the vertical distribution of long-lived Th isotopes in seawater and measured aerosol Th solubility. The dust-borne Fe deposition flux in the tropical western North Pacific was further estimated as 4.02–12.55 mg m⁻² yr⁻¹, using the measured S_{<em>Fe/Th</em>}. Both estimated dust and dust-borne Fe deposition fluxes agree well with the dust deposition model. The spatial variability of surface dissolved Fe and primary production were predominantly driven by dust-borne Fe deposition as supported by their significant correlation. Dust-borne Fe input regulated the spatial distribution of Fe:N supply ratios, which, in turn, affected the growth of marine phytoplankton, notably diazotrophs, by stimulating N₂-fixation. Quantification of dust-borne Fe fluxes may improve our understanding of the biogeochemical cycling of Fe and N₂-fixation process in the tropical western North Pacific.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104740"},"PeriodicalIF":4.0,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Reef Island Geomorphic Activity Assessment: A new approach to quantify cay geomorphic change","authors":"Emily Lazarus ,&nbsp;Stephanie Duce ,&nbsp;Stephen Lewis ,&nbsp;Scott Smithers","doi":"10.1016/j.gloplacha.2025.104743","DOIUrl":"10.1016/j.gloplacha.2025.104743","url":null,"abstract":"<div><div>Cays (low-lying reef islands) are dynamic, unconsolidated sedimentary landforms which adjust their shape and position on a reef in response to hydrodynamic conditions and sediment supply. Quantifying meaningful cay geomorphic change is necessary to understand their natural variability and detect change patterns and trajectories. Shoreline movements on cays have been quantified globally using the Digital Shoreline Analysis System (DSAS) which records shoreline movements at regularly spaced shore-normal transects. However, DSAS was developed for relatively straight coasts and is less suited to cays which have 360° shorelines. Here we introduce the Reef Island Geomorphic Activity Assessment (RIGAA), an alternative approach to quantify changes to cay area and shape, orientation, and position that uses the entire cay footprint. To compare the RIGAA to the DSAS, we used digitised cay shorelines captured monthly for three cays on the Great Barrier Reef to quantify cay geomorphic change over almost a decade (2015–2023). Both approaches yield comparable assessments of net cay shoreline change but the DSAS overall Net Shoreline Movement metric suggests progradation (4.14–13.12 m) dominates at all cays whereas the RIGAA indicates more diverse behaviours, including shoreline contraction (Taylor Cay −32.8 %), expansion (Bushy Islet +22.9 %) and stability (Masthead Island +2.9 %). The RIGAA approach accounts for the frequency and magnitude of shoreline perturbations and provides a comprehensive assessment of cay morphodynamic behaviour applied to the entire cay footprint. The outputs provide meaningful metrics for a range of users, including key information about overall cay area and morphological change, and movement.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104743"},"PeriodicalIF":4.0,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variations of Asian summer monsoon and regional hydroclimate between the MIS 7.1 and 6.5","authors":"Xiumin Zhai ,&nbsp;Jingwei Zhang ,&nbsp;Yi Li ,&nbsp;Yijia Liang ,&nbsp;Kan Zhao ,&nbsp;Qingfeng Shao ,&nbsp;Yongjin Wang ,&nbsp;Xinggong Kong","doi":"10.1016/j.gloplacha.2025.104739","DOIUrl":"10.1016/j.gloplacha.2025.104739","url":null,"abstract":"<div><div>Paleoclimatic evidence provides critical insights into the rhythm and mechanisms of the Asian summer monsoon (ASM). In this study, 1221 paired stalagmite δ¹⁸O and δ¹³C records, constrained by 20 U/Th dates, are used to reconstruct ASM and regional hydroclimate changes between MIS 7.1 and 6.5 (∼196.6 and ∼ 166.0 kyr BP). The major findings are as follows: 1) ASM changes did not consistently align with North Hemispher summer insolation (NHSI) variations, especially between ∼186.0 and ∼ 180.0 kyr BP. This asynchrony pattern likely occurred during higher precession and lower minima, suggesting that the NHSI may have reached to a threshold-like value and then triggered a collapse of the Atlantic meridional overturning circulation (AMOC) lasting for thousands of years, thus delaying the recovery of ASM via “high-low teleconnection” mechanism. 2) Within a single precession cycle, millennial-scale ASM failures occurred at an interval of ∼10.0 kyrs, this pattern corresponds to changes in the El Niño-Southern Oscillation, and climate proxy records in the warm pool regions, evidencing a fundamental role of prcesssion induced low-latitude processes in modulating the millennial-scale ASM failures. 3) Over the long-term, hydroclimate changes at the cave site are in line with an expansion of ice-volume and a strengthening winter monsoon.These broadly similar patterns suggest that regional hydroclimate variations are more strongly influenced by ice-volume and its feedback in oceanic-atmospheric anomalies than by precession induced insolation forcing.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104739"},"PeriodicalIF":4.0,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of cut-off lows on dust transport from the Great Lakes Basin to northern China","authors":"Lunga Su ,&nbsp;Zuowei Xie ,&nbsp;Mei Yong ,&nbsp;Chenglai Wu ,&nbsp;Zelun Cheng ,&nbsp;Gomboluudev Purevjav ,&nbsp;Cholaw Bueh ,&nbsp;Yuhai Bao","doi":"10.1016/j.gloplacha.2025.104738","DOIUrl":"10.1016/j.gloplacha.2025.104738","url":null,"abstract":"<div><div>In the context of global warming, the Great Lakes Basin in western Mongolia is undergoing escalating desertification, making it as an increasingly important dust source in Mongolia. This study investigated the dust transport from the Great Lakes Basin and its modulating circulation using ERA5 reanalysis data and applying the Lagrangian analysis tool (LAGRANTO) to the WRF-Chem simulation of two typical dust storm events in 2021 and 2023. The dust from the Great Lakes Basin and their subsequent transport toward China were primarily influenced by tropospheric cut-off lows. Cold advection to the west and warm advection to the east of the cut-off lows favored the development of near-surface anticyclones and cyclones, respectively. Between them, pronounced northwesterly and upward winds prevailed, lifting dust from the Great Lakes Basin into the troposphere. The cut-off lows transported the dust mainly eastward and southeastward, depending on their shape. A regional cut-off low deepened in the westerlies, driving dust eastward toward the Great Khingan and then in an anticlockwise direction toward the Changbai Mountain. In contrast, a zonally elongated cut-off low, associated with pronounced cold advection in the west, facilitated the near-surface anticyclone's southeastward extension. Consequently, dust from the Great Lakes Basin was primarily transported southeastward, affecting northern China. The cut-off lows influencing dust weather over northern China were predominantly located from Lake Baikal to Northeast China. Their high occurrence could have contributed to the rise in dust events over northern China in 2021 and 2023.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104738"},"PeriodicalIF":4.0,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A decrease in low-latitude weathering flux facilitated the demise of the Late Paleozoic Ice Age","authors":"Shi Sun ,&nbsp;Anqing Chen ,&nbsp;Mingcai Hou ,&nbsp;James G. Ogg ,&nbsp;Qian Li ,&nbsp;Shuai Yang ,&nbsp;Guanghui Huang ,&nbsp;Runan Yong","doi":"10.1016/j.gloplacha.2025.104730","DOIUrl":"10.1016/j.gloplacha.2025.104730","url":null,"abstract":"<div><div>The Late Paleozoic Ice Age (LPIA) was a series of modulated glacial-interglacial pulses that characterized the climate of the late Carboniferous through Permian. Although the ages and durations of the main major episodes of the LPIA have been calibrated from glacial deposits in eastern Australia and elsewhere, the causal factors for the final transition from the oscillating icehouse climate to a continuous hothouse remains uncertain. To aid in unraveling the potential causes for this climatic turnover and its characteristics in the tropical latitudes, we measured the weathering indices and redox proxies recorded by the Lopingian (Late Permian) strata in the Shangsi section of the Upper Yangtze region in South China. The multiple weathering indices derived from the geochemical composition of the acid-insoluble residues in the carbonate rocks exhibit consistent trends. These trends, when combined with published coeval weathering data from other regions, trace four global phases of weathering changes during the late Permian. After the middle Wuchiapingian, the observed increase in the weathering indices and a negative excursion in carbon isotope are apparent responses to gradual warming. The simultaneous increase in ocean oxygenation may have also played a role in the deglaciation. Based on the changes in tropical exposed land area through the late Permian, we quantitatively estimated the low-latitude chemical weathering flux by combining contemporaneous weathering indicators. The curve of that estimated flux support the hypothesis that a sustained decrease in low-latitudes weathering flux, the implied apparent decrease in the amount of exposure and total weathering of silicate rocks, may caused a weakening of the carbon sink and a continuous accumulation of atmospheric CO₂, which in turn facilitate the stepwise deglaciation of LPIA and the onset of a long-term hothouse climate.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104730"},"PeriodicalIF":4.0,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear feedback of Asian summer monsoon to abrupt events in North Atlantic: Evidence from a precisely dated speleothem record during late MIS3","authors":"Xi Chen ,&nbsp;Jingyao Zhao ,&nbsp;Kexin Wang ,&nbsp;Xiyu Dong ,&nbsp;Jiahui Cui ,&nbsp;Liangkang Pan ,&nbsp;Carlos Pérez-Mejías ,&nbsp;Hai Cheng","doi":"10.1016/j.gloplacha.2025.104733","DOIUrl":"10.1016/j.gloplacha.2025.104733","url":null,"abstract":"<div><div>Millennial-scale climate oscillations, particularly Dansgaard-Oeschger (DO) events, were prevalent during Marine Isotope Stage 3 (MIS3), but their regional responses/feedbacks remain poorly understood. We present a high-resolution (∼4 years) speleothem δ¹⁸O record from the Sichuan Basin, spanning late MIS3, with 56 precise ^{<span>230</span>}Th dates (∼ ± 60 years) and approximately ∼4804 fluorescence annual laminas, to constrain the Asian summer monsoon (ASM) response/feedback to the millennial-scale climate oscillations. Our results show that the varying durations of strong and weak ASM phases during DO events reinforce the important role of atmospheric CO₂ levels and orbital parameters (precession and obliquity) in shaping the nonlinear feedbacks of millennial-scale climate variability. These findings are consistent with recent climate simulations, which emphasize the influence of CO₂ and orbital factors on the balance between tropical net precipitation and subpolar sea-ice shelves in the North Atlantic. In addition, all transitions from weak to strong monsoon phases during the DO cycles extended to centennial timescales (∼153–233 years), in contrast to the abrupt, decadal-scale oxygen isotope transitions in Greenland influenced by regional sea-ice shelves changes in the North Atlantic. This observation suggests a relatively gradual change in the Atlantic Meridional Overturning Circulation during these periods, providing new insights into the dynamics of past climate transitions.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"247 ","pages":"Article 104733"},"PeriodicalIF":4.0,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}