Pub Date : 2026-01-18DOI: 10.1016/j.gloplacha.2026.105318
Bronwen S. Whitney, Danilo M. Neves, Nicholas J.D. Loughlin, Carlos D'Apolito, Coblinski Tavares Carla, Emma P. Hocking, Francis E. Mayle, Mitchell J. Power, , Mario L. Assine
{"title":"Millennial-scale fire and climate dynamics in the world's largest tropical wetland show emerging fire threat to flooded ecosystems","authors":"Bronwen S. Whitney, Danilo M. Neves, Nicholas J.D. Loughlin, Carlos D'Apolito, Coblinski Tavares Carla, Emma P. Hocking, Francis E. Mayle, Mitchell J. Power, , Mario L. Assine","doi":"10.1016/j.gloplacha.2026.105318","DOIUrl":"https://doi.org/10.1016/j.gloplacha.2026.105318","url":null,"abstract":"","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"4 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2026-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995742","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}
The wider occurrence of high topography on the eastern side of the Tibetan Plateau compared to the western side has sparked debate about the geodynamic mechanisms responsible for eastward plateau growth. Existing end-member models highlight either coherent block extrusion dominated by localized deformation along major faults, or plateau-scale distributed deformation driven by lower crustal flow. These two models have contrasting predictions in terms of spatial pattern of deformation and rock exhumation. Here, we reconstruct the Cenozoic exhumation pattern along a ∼ 150-km-long transect perpendicular to the NE-striking Ailaoshan-Red River shear zone, one of the largest Cenozoic strike-slip faults in the southeastern Tibetan Plateau. Exhumation rate modeling using new and published thermochronological ages shows a high spatial variation. Results reveal a sharp decrease from rapid Oligocene (∼1.9–4.1 km/m.y.) and Miocene (∼0.1–0.15 km/m.y.) exhumation within the ∼15 km-wide central Ailao Shan shear zone to minimum exhumation (∼0.03 km/m.y.) in the surrounding regions. Such a spatially short-wavelength exhumation pattern conflicts with models predicting long-wavelength deformation of crust, but supports the important role of highly localized deformation along major faults dominating the eastward plateau growth.
{"title":"Spatially focused exhumation supports short-wavelength deformation in the southeastern Tibetan Plateau","authors":"Guihong Zhang , Yuntao Tian , Philippe Hervé Leloup , Zengjie Zhang , Peizhen Zhang","doi":"10.1016/j.gloplacha.2026.105319","DOIUrl":"10.1016/j.gloplacha.2026.105319","url":null,"abstract":"<div><div>The wider occurrence of high topography on the eastern side of the Tibetan Plateau compared to the western side has sparked debate about the geodynamic mechanisms responsible for eastward plateau growth. Existing end-member models highlight either coherent block extrusion dominated by localized deformation along major faults, or plateau-scale distributed deformation driven by lower crustal flow. These two models have contrasting predictions in terms of spatial pattern of deformation and rock exhumation. Here, we reconstruct the Cenozoic exhumation pattern along a ∼ 150-km-long transect perpendicular to the NE-striking Ailaoshan-Red River shear zone, one of the largest Cenozoic strike-slip faults in the southeastern Tibetan Plateau. Exhumation rate modeling using new and published thermochronological ages shows a high spatial variation. Results reveal a sharp decrease from rapid Oligocene (∼1.9–4.1 km/m.y.) and Miocene (∼0.1–0.15 km/m.y.) exhumation within the ∼15 km-wide central Ailao Shan shear zone to minimum exhumation (∼0.03 km/m.y.) in the surrounding regions. Such a spatially short-wavelength exhumation pattern conflicts with models predicting long-wavelength deformation of crust, but supports the important role of highly localized deformation along major faults dominating the eastward plateau growth.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"258 ","pages":"Article 105319"},"PeriodicalIF":4.0,"publicationDate":"2026-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995744","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}
The Dongsheng region of the Ordos Basin (China) contains important sandstone-hosted uranium deposits that reveal an evolving interaction of geochemical evolution and tectono-sedimentary dynamics. The present work combines whole-rock and carbon‑sulfur isotopic compositions to understand the origin and formation of uranium metallogeny within the Middle Jurassic intracontinental Zhiluo Formation of the Ordos Basin. The δ13C values (−26.7‰ to −2.2‰) of calcite-cement indicate that the carbon mainly originated through biochemical remineralization. Negative and variable δ13C values indicate a strong biogenic carbon contribution, while positive excursions reflect mantle or inorganic inputs. Additionally, the δ34S composition (−25.2‰ to 10.2‰) indicates the mutual inputs from bacterial sulfate reduction and Rayleigh fractionation. The broad δ34S range of pyrite similarly points to multiple sources, with a strong bacterial sulfate reduction signal. Trace element patterns show Light Rare Earth Element (LREE) enrichment, Heavy Rare Earth Elements (HREE) depletion, and distinctive “W-shaped” anomalies (e.g., Nd, Nb, Zr), consistent with reductive immobilization under diagenetic conditions. Tectonic reconstruction and sedimentary provenance support a deposition along an active continental margin with felsic to intermediate source rocks. The Zhiluo Formation was deposited in arid to semi-arid settings, as evidenced by low Rb/Sr and high Sr/Cu and Sr/Ba ratios, reflecting high paleosalinity and strong evaporation. A revised genetic model is here proposed in which oxidized uranium-bearing groundwater interacts with both locally derived organic matter and hydrocarbon-charged reducing fluids (e.g., CH4, CO, H2S, CO2) along structurally controlled fluid pathways, resulting in redox-driven uranium precipitation. This integrated isotopic–geochemical framework not only refines the mineralization model for the Dongsheng deposit but also provides a predictive approach for uranium exploration in analogous basinal settings worldwide. Our outcomes stress the wider role of microbial-hydrocarbon cycling in modulating uranium deposits across continental settings.
{"title":"Geochemical and isotopic insights into uranium mineralization in the Dongsheng Area (Ordos Basin, NW China): Implications for global uranium systems","authors":"Shamim Akhtar , Tehseen Zafar , Xiaoyong Yang , Fabrizio Frontalini","doi":"10.1016/j.gloplacha.2026.105313","DOIUrl":"10.1016/j.gloplacha.2026.105313","url":null,"abstract":"<div><div>The Dongsheng region of the Ordos Basin (China) contains important sandstone-hosted uranium deposits that reveal an evolving interaction of geochemical evolution and tectono-sedimentary dynamics. The present work combines whole-rock and carbon‑sulfur isotopic compositions to understand the origin and formation of uranium metallogeny within the Middle Jurassic intracontinental Zhiluo Formation of the Ordos Basin. The δ<sup>13</sup>C values (−26.7‰ to −2.2‰) of calcite-cement indicate that the carbon mainly originated through biochemical remineralization. Negative and variable δ<sup>13</sup>C values indicate a strong biogenic carbon contribution, while positive excursions reflect mantle or inorganic inputs. Additionally, the δ<sup>34</sup>S composition (−25.2‰ to 10.2‰) indicates the mutual inputs from bacterial sulfate reduction and Rayleigh fractionation. The broad δ<sup>34</sup>S range of pyrite similarly points to multiple sources, with a strong bacterial sulfate reduction signal. Trace element patterns show Light Rare Earth Element (LREE) enrichment, Heavy Rare Earth Elements (HREE) depletion, and distinctive “W-shaped” anomalies (e.g., Nd, Nb, Zr), consistent with reductive immobilization under diagenetic conditions. Tectonic reconstruction and sedimentary provenance support a deposition along an active continental margin with felsic to intermediate source rocks. The Zhiluo Formation was deposited in arid to semi-arid settings, as evidenced by low Rb/Sr and high Sr/Cu and Sr/Ba ratios, reflecting high paleosalinity and strong evaporation. A revised genetic model is here proposed in which oxidized uranium-bearing groundwater interacts with both locally derived organic matter and hydrocarbon-charged reducing fluids (e.g., CH<sub>4</sub>, CO, H<sub>2</sub>S, CO<sub>2</sub>) along structurally controlled fluid pathways, resulting in redox-driven uranium precipitation. This integrated isotopic–geochemical framework not only refines the mineralization model for the Dongsheng deposit but also provides a predictive approach for uranium exploration in analogous basinal settings worldwide. Our outcomes stress the wider role of microbial-hydrocarbon cycling in modulating uranium deposits across continental settings.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"258 ","pages":"Article 105313"},"PeriodicalIF":4.0,"publicationDate":"2026-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995741","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}
Pub Date : 2026-01-17DOI: 10.1016/j.gloplacha.2026.105316
Ting Chen , Yixuan Wang , Ran Wei , Yi Zhong , Qingsong Liu
The causes of Northern Hemisphere Glaciation (NHG) during the Pliocene remain controversial. The western North Pacific Subtropical Gyre (wNPSG), the dominant conduit for poleward heat and moisture transport, may have modulated NHG development, yet its Pliocene evolution remain unconstrained. In this study, we analyzed diatom assemblage changes along the northern boundary of the wNPSG to investigate its meridional displacement. We compared these changes with those of the eastern NPSG (eNPSG) reconstructed using compiled published sea surface temperature data, and examined their linkages to the NHG. The diatom assemblages indicate a northward expansion of the wNPSG from ∼5.8 Ma to ∼4.5 Ma. This wNPSG expansion coincided with an expansion of the eNPSG, both likely related to global warming. Subsequently, a continued northward expansion of the wNPSG occurred between ∼4.5 Ma and ∼ 3.7 Ma, corresponding to an expansion of the Western Pacific Warm Pool but an eNPSG contraction. These contrasting changes probably linked to stronger easterly trade winds driven by an increased SST gradient between low- to mid-latitudes. We propose that the northward expansion of wNPSG during this period likely suppressed NHG formation until ∼3.7–3.5 Ma by transporting more heat to high latitudes via oceanic and atmospheric circulations. From ∼3.7 Ma to ∼2.5 Ma, diatom assemblages indicate that wNPSG retreated southward, coinciding with the onset of NHG. This study highlights the different behavior of the wNPSG versus the eNPSG during the early Pliocene and its potential role in suppressing the onset of NHG until ∼3.7 Ma.
{"title":"Contrasting meridional displacement of the western and eastern North Pacific Subtropical Gyre occurred during ∼4.5–3.5 Ma: A response to strengthened SST gradient","authors":"Ting Chen , Yixuan Wang , Ran Wei , Yi Zhong , Qingsong Liu","doi":"10.1016/j.gloplacha.2026.105316","DOIUrl":"10.1016/j.gloplacha.2026.105316","url":null,"abstract":"<div><div>The causes of Northern Hemisphere Glaciation (NHG) during the Pliocene remain controversial. The western North Pacific Subtropical Gyre (wNPSG), the dominant conduit for poleward heat and moisture transport, may have modulated NHG development, yet its Pliocene evolution remain unconstrained. In this study, we analyzed diatom assemblage changes along the northern boundary of the wNPSG to investigate its meridional displacement. We compared these changes with those of the eastern NPSG (eNPSG) reconstructed using compiled published sea surface temperature data, and examined their linkages to the NHG. The diatom assemblages indicate a northward expansion of the wNPSG from ∼5.8 Ma to ∼4.5 Ma. This wNPSG expansion coincided with an expansion of the eNPSG, both likely related to global warming. Subsequently, a continued northward expansion of the wNPSG occurred between ∼4.5 Ma and ∼ 3.7 Ma, corresponding to an expansion of the Western Pacific Warm Pool but an eNPSG contraction. These contrasting changes probably linked to stronger easterly trade winds driven by an increased SST gradient between low- to mid-latitudes. We propose that the northward expansion of wNPSG during this period likely suppressed NHG formation until ∼3.7–3.5 Ma by transporting more heat to high latitudes via oceanic and atmospheric circulations. From ∼3.7 Ma to ∼2.5 Ma, diatom assemblages indicate that wNPSG retreated southward, coinciding with the onset of NHG. This study highlights the different behavior of the wNPSG versus the eNPSG during the early Pliocene and its potential role in suppressing the onset of NHG until ∼3.7 Ma.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"258 ","pages":"Article 105316"},"PeriodicalIF":4.0,"publicationDate":"2026-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995740","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}
Pub Date : 2026-01-17DOI: 10.1016/j.gloplacha.2026.105293
Harry J. Dowsett, Kevin M. Foley
Paleoclimate researchers have been comparing Pliocene environmental data to paleoclimate model results since the 1980s. The Pliocene Model Intercomparison Project (PlioMIP) began in 2008 with a focus on the Late Pliocene. Here we assess the availability and utility of sea surface temperature (SST) data for verification of Pliocene Model Intercomparison Project (PlioMIP3) Early Pliocene (Zanclean) experiments. We analyze published data in terms of quantity and spatial distribution. Only SST estimates derived using alkenone paleo thermometry are reported, and all estimates are based upon the same temperature calibration. Sea surface temperature data are selected from within three distinct time intervals: The early Zanclean 5.3 Ma – 4.2 Ma time slab, and two time slices within the early Zanclean, chosen by PlioMIP3 at 4.870 Ma and 4.474 Ma. Results show the early Zanclean time slab contains 2055 individual estimates. Approximately ∼ 80% of these estimates come from Sites 609, 642, 846, 847, 882, 907, and 1146. There are 17 sites with a total of 42 estimates within the 4.474 Ma ±10 kyr time slice, and 15 sites with a total of 47 data points within the 4.870 Ma ±10 kyr interval. The sparse spatial and temporal distribution of Zanclean data, relative to the data available for the mid Piacenzian, makes point-by-point data model comparison suspect. We suggest interpreting model output against lower resolution long term trends in proxy data, and comparison of models through temperature gradients, may be the most useful application of currently available data. Integrating Zanclean age coastal plain sequences within data model comparison schemes, for increased understanding of regional climate impacts, also holds great potential.
{"title":"Early Pliocene (Zanclean) sea surface temperature for PlioMIP3","authors":"Harry J. Dowsett, Kevin M. Foley","doi":"10.1016/j.gloplacha.2026.105293","DOIUrl":"10.1016/j.gloplacha.2026.105293","url":null,"abstract":"<div><div>Paleoclimate researchers have been comparing Pliocene environmental data to paleoclimate model results since the 1980s. The Pliocene Model Intercomparison Project (PlioMIP) began in 2008 with a focus on the Late Pliocene. Here we assess the availability and utility of sea surface temperature (SST) data for verification of Pliocene Model Intercomparison Project (PlioMIP3) Early Pliocene (Zanclean) experiments. We analyze published data in terms of quantity and spatial distribution. Only SST estimates derived using alkenone paleo thermometry are reported, and all estimates are based upon the same temperature calibration. Sea surface temperature data are selected from within three distinct time intervals: The early Zanclean 5.3 Ma – 4.2 Ma time slab, and two time slices within the early Zanclean, chosen by PlioMIP3 at 4.870 Ma and 4.474 Ma. Results show the early Zanclean time slab contains 2055 individual estimates. Approximately ∼ 80% of these estimates come from Sites 609, 642, 846, 847, 882, 907, and 1146. There are 17 sites with a total of 42 estimates within the 4.474 Ma ±10 kyr time slice, and 15 sites with a total of 47 data points within the 4.870 Ma ±10 kyr interval. The sparse spatial and temporal distribution of Zanclean data, relative to the data available for the mid Piacenzian, makes point-by-point data model comparison suspect. We suggest interpreting model output against lower resolution long term trends in proxy data, and comparison of models through temperature gradients, may be the most useful application of currently available data. Integrating Zanclean age coastal plain sequences within data model comparison schemes, for increased understanding of regional climate impacts, also holds great potential.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"259 ","pages":"Article 105293"},"PeriodicalIF":4.0,"publicationDate":"2026-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995745","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}
Pub Date : 2026-01-16DOI: 10.1016/j.gloplacha.2026.105321
Sharmila Sherin , Manish Tiwari , Vikash Kumar
The Indian monsoon is highly sensitive to tropical Indian Ocean SST, which exhibits significant variability on various timescales. Here we reconstruct the surface and thermocline temperatures of the northern equatorial Indian Ocean for the past 37 kyr, using Mg/Ca ratios of the surface- and thermocline-dwelling foraminifera. Our findings indicate a consistent warming trend at the surface and thermocline during the cold Heinrich Stadials, coinciding with Antarctic Isotope Maxima (AIM) events and superimposed on the zonal negative dipole structure in the equatorial Indian Ocean. We further support this using a transient climate simulation (TraCE-21ka), which shows that warming of the Southern Ocean during North Atlantic stadials influenced the north equatorial Indian Ocean surface hydroclimate through northward tunnelling of Southern Ocean water masses. With the projected rise in Antarctic and Southern Ocean temperatures, the oceanic tunnels linking southern high-latitude and tropical Indian Ocean climates may have a significant impact on monsoon hydrology.
{"title":"Antarctic warming affects northern Equatorial Indian Ocean SST via oceanic tunnels","authors":"Sharmila Sherin , Manish Tiwari , Vikash Kumar","doi":"10.1016/j.gloplacha.2026.105321","DOIUrl":"10.1016/j.gloplacha.2026.105321","url":null,"abstract":"<div><div>The Indian monsoon is highly sensitive to tropical Indian Ocean SST, which exhibits significant variability on various timescales. Here we reconstruct the surface and thermocline temperatures of the northern equatorial Indian Ocean for the past 37 kyr, using Mg/Ca ratios of the surface- and thermocline-dwelling foraminifera. Our findings indicate a consistent warming trend at the surface and thermocline during the cold Heinrich Stadials, coinciding with Antarctic Isotope Maxima (AIM) events and superimposed on the zonal negative dipole structure in the equatorial Indian Ocean. We further support this using a transient climate simulation (TraCE-21ka), which shows that warming of the Southern Ocean during North Atlantic stadials influenced the north equatorial Indian Ocean surface hydroclimate through northward tunnelling of Southern Ocean water masses. With the projected rise in Antarctic and Southern Ocean temperatures, the oceanic tunnels linking southern high-latitude and tropical Indian Ocean climates may have a significant impact on monsoon hydrology.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"258 ","pages":"Article 105321"},"PeriodicalIF":4.0,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995748","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}
Pub Date : 2026-01-16DOI: 10.1016/j.gloplacha.2026.105315
K. Rubio-Sandoval , T.A. Shaw , M. Vacchi , N. Khan , B.P. Horton , J.R. Angulo , M. Pappalardo , A.L. Ferreira-Júnior , S. Richiano , M.C. de Souza , P.C. Giannini , D.D. Ryan , E.J. Gowan , A. Rovere
Holocene relative sea-level (RSL) changes along the Atlantic coast of South America reflect a complex interplay between ice equivalent sea-level, glacio-isostatic adjustment (GIA), regional tectonics, and local sedimentary processes. However, the uneven spatial and temporal resolution of existing Holocene RSL data has hindered regional assessments. Here, we compile and standardize 1108 RSL data points from Brazil, Uruguay, Argentina, and Chilean Tierra del Fuego, creating the first comprehensive database for the southwestern Atlantic. The data reveals a widespread Mid-Holocene highstand between 7000 and 4000 years BP, with RSL rising 2 to 4 m above present-day sea level, followed by a gradual fall to present. This pattern is consistent with GIA model predictions across the region's > 50° latitudinal span. Peak rates of RSL change occurred during the Early to Mid-Holocene transition, reaching up to 17.2 mm/yr in Tierra del Fuego and decreasing to 1.6 mm/yr near the Amazon delta. After 5000 years cal BP, RSL started to fall at 0.5 mm/yr. This Atlantic coast of South America database fills a critical geographic gap and provides a robust framework for refining GIA models and understanding sea-level evolution during the Holocene in the Southern Hemisphere.
{"title":"Holocene relative sea-level changes from the Atlantic coasts of South America","authors":"K. Rubio-Sandoval , T.A. Shaw , M. Vacchi , N. Khan , B.P. Horton , J.R. Angulo , M. Pappalardo , A.L. Ferreira-Júnior , S. Richiano , M.C. de Souza , P.C. Giannini , D.D. Ryan , E.J. Gowan , A. Rovere","doi":"10.1016/j.gloplacha.2026.105315","DOIUrl":"10.1016/j.gloplacha.2026.105315","url":null,"abstract":"<div><div>Holocene relative sea-level (RSL) changes along the Atlantic coast of South America reflect a complex interplay between ice equivalent sea-level, glacio-isostatic adjustment (GIA), regional tectonics, and local sedimentary processes. However, the uneven spatial and temporal resolution of existing Holocene RSL data has hindered regional assessments. Here, we compile and standardize 1108 RSL data points from Brazil, Uruguay, Argentina, and Chilean Tierra del Fuego, creating the first comprehensive database for the southwestern Atlantic. The data reveals a widespread Mid-Holocene highstand between 7000 and 4000 years BP, with RSL rising 2 to 4 m above present-day sea level, followed by a gradual fall to present. This pattern is consistent with GIA model predictions across the region's > 50° latitudinal span. Peak rates of RSL change occurred during the Early to Mid-Holocene transition, reaching up to 17.2 mm/yr in Tierra del Fuego and decreasing to 1.6 mm/yr near the Amazon delta. After 5000 years cal BP, RSL started to fall at 0.5 mm/yr. This Atlantic coast of South America database fills a critical geographic gap and provides a robust framework for refining GIA models and understanding sea-level evolution during the Holocene in the Southern Hemisphere.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"259 ","pages":"Article 105315"},"PeriodicalIF":4.0,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995747","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}
Pub Date : 2026-01-16DOI: 10.1016/j.gloplacha.2026.105314
Arturo Lucas , Sven Pallacks , Alessandro Incarbona , P. Graham Mortyn , Patrizia Ziveri
Climate-driven shifts in species diversity, community composition and phenology can disrupt ecosystem functioning and compromise marine ecosystem stability. The Mediterranean Sea, a global biodiversity hotspot, is particularly vulnerable to anthropogenic climate change and is experiencing a growing biodiversity crisis especially driven by warming, habitat degradation, pollution and the introduction of new species. Yet, current knowledge of biodiversity changes in this region is largely limited to shallow shelf benthic communities and macroorganisms. Calcifying phytoplankton and zooplankton, however, offer a unique lens into pelagic ecosystem dynamics, as their fossil record preserves signals of biodiversity change in deep-sea sediments spanning the Industrial Era and the current phase of rapid warming. This study focuses on the reconstruction of diversity change of two dominant calcifying plankton groups: coccolithophores and foraminifera (primary and secondary producers). We examine two selected sedimentary records of the western and central Mediterranean—Alboran Sea and the Strait of Sicily—spanning the last ∼1700 and 200 years of modern climate, respectively. By quantifying abundance, diversity and turnover of species composition we evaluate the potential response of calcifying plankton assemblages to oceanographic changes under anthropogenic climate change. The results revealed contrasting changes in the diversity of the two dominant calcifying plankton groups, with a rapid increase in coccolithophore diversity alongside a decrease in planktonic foraminiferal diversity during the Industrial Era. We attribute these group-specific responses to ecological and physiological differences, particularly in relation to life cycles and water column distribution, under increasingly stratified, nutrient-depleted surface waters driven by rising sea surface temperatures. In addition, this study provides first indication of tropicalization of the western Mediterranean plankton derived from the increasing intrusion and eastward expansion of the coccolithophore Gephyrocapsa oceanica from the Strait of Gibraltar into the Mediterranean Sea. The highest abundances of this species are restricted to the Equatorial Atlantic Divergence Zone and only found in higher proportions in the Mediterranean during past warm periods. Although the temperate-productivity foraminiferal species of Globigerina bulloides and Globorotalia inflata remain the dominant foraminiferal species, previous minor dominant species are being replaced by warm-oligotrophic species, such as Trilobatus sacculifer and Globigerinella spp. These align with model projections of tropical species migrating into the area, previously documented among benthic organisms and point to a broader restructuring of planktonic life.
{"title":"Tropicalization and biodiversity restructuring of calcifying plankton in a rapidly warming Mediterranean Sea","authors":"Arturo Lucas , Sven Pallacks , Alessandro Incarbona , P. Graham Mortyn , Patrizia Ziveri","doi":"10.1016/j.gloplacha.2026.105314","DOIUrl":"10.1016/j.gloplacha.2026.105314","url":null,"abstract":"<div><div>Climate-driven shifts in species diversity, community composition and phenology can disrupt ecosystem functioning and compromise marine ecosystem stability. The Mediterranean Sea, a global biodiversity hotspot, is particularly vulnerable to anthropogenic climate change and is experiencing a growing biodiversity crisis especially driven by warming, habitat degradation, pollution and the introduction of new species. Yet, current knowledge of biodiversity changes in this region is largely limited to shallow shelf benthic communities and macroorganisms. Calcifying phytoplankton and zooplankton, however, offer a unique lens into pelagic ecosystem dynamics, as their fossil record preserves signals of biodiversity change in deep-sea sediments spanning the Industrial Era and the current phase of rapid warming. This study focuses on the reconstruction of diversity change of two dominant calcifying plankton groups: coccolithophores and foraminifera (primary and secondary producers). We examine two selected sedimentary records of the western and central Mediterranean—Alboran Sea and the Strait of Sicily—spanning the last ∼1700 and 200 years of modern climate, respectively. By quantifying abundance, diversity and turnover of species composition we evaluate the potential response of calcifying plankton assemblages to oceanographic changes under anthropogenic climate change. The results revealed contrasting changes in the diversity of the two dominant calcifying plankton groups, with a rapid increase in coccolithophore diversity alongside a decrease in planktonic foraminiferal diversity during the Industrial Era. We attribute these group-specific responses to ecological and physiological differences, particularly in relation to life cycles and water column distribution, under increasingly stratified, nutrient-depleted surface waters driven by rising sea surface temperatures. In addition, this study provides first indication of tropicalization of the western Mediterranean plankton derived from the increasing intrusion and eastward expansion of the coccolithophore <em>Gephyrocapsa oceanica</em> from the Strait of Gibraltar into the Mediterranean Sea. The highest abundances of this species are restricted to the Equatorial Atlantic Divergence Zone and only found in higher proportions in the Mediterranean during past warm periods. Although the temperate-productivity foraminiferal species of <em>Globigerina bulloides</em> and <em>Globorotalia inflata</em> remain the dominant foraminiferal species, previous minor dominant species are being replaced by warm-oligotrophic species, such as <em>Trilobatus sacculifer</em> and <em>Globigerinella</em> spp. These align with model projections of tropical species migrating into the area, previously documented among benthic organisms and point to a broader restructuring of planktonic life.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"259 ","pages":"Article 105314"},"PeriodicalIF":4.0,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995746","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}
Pub Date : 2026-01-14DOI: 10.1016/j.gloplacha.2026.105308
Ramesh Glückler , Shiro Tsuyuzaki , Ulrike Herzschuh , Luidmila A. Pestryakova , Elisabeth Dietze , Stefan Kruse , Youhei Yamashita
Intensifying fire regimes threaten to disturb the ecological balance among larch-dominated forests, permafrost, and historically low-intensity surface fires in the Republic of Sakha (Yakutia), known as Earth's coldest inhabited region. This ecological balance is currently considered to stabilize this unique ecosystem and its function as a continental-scale carbon reservoir. Here, we present the first paleoecological reconstructions of wildfire intensities, using benzene polycarboxylic acids (BPCAs) in lake sediments from the lowland of Central Yakutia and the highland of the southern Verkhoyansk Mountains as a proxy for fire intensity. Results reveal changes of BPCA-derived pyrogenic carbon concentration (BPCA-PyC) and inferred fire intensity over the past c. 7600 years. Unexpectedly, the highland region recorded higher levels of BPCA-PyC and fire intensity than the lowland region. Our results separate a shrub fire regime in the highland from a forest ground fire regime in the lowland, highlighting both an increased variability of fire regimes in the lowland since the Mid-Holocene and stable multi-centennial-scale fire intensity in the highland since the Late Holocene. This raises questions about potential future shifts in fire regimes and their ecological impacts. A separate application of the BPCA method to extracted macroscopic charcoal particles indicates their origin from low-intensity, smoldering fires, contrasting with smaller pyrogenic carbon components in the sediment matrix. We discuss effects of dominant fire regimes, lake size and setting, and proxy taphonomy on sedimentary pyrogenic carbon. This study highlights benefits of applying a mix of fire proxies, while providing an initial perspective on long-term changes of fire intensity for eastern Siberia.
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Pub Date : 2026-01-14DOI: 10.1016/j.gloplacha.2026.105300
Jiaju Zhao , Qianwen Zhang , Zhongwei Shen , Zhiping Zhang , Jie Chen , Lin Chen , Jinzhao Liu , Yunning Cao , Jing Hu
Understanding the evolution and mechanisms of past droughts can provide critical insights for drought prediction in northern China in the context of global warming. During the late Holocene, drought was frequently in northern China; however, its spatial patterns and intensities have received less attention. Here, we present a high-resolution moisture record based on alkenone proxies from Daihai Lake (Inner Mongolia, China), which indicates a long-term decline in water depth in spring during the late Holocene. Notably, significant reductions in water depth were observed during the periods of ca. 4.3–3.4 cal ka BP, 2.5–2.2 cal ka BP, 1.5–0.8 cal ka BP, and the current warm period. In conjunction with published reconstructed precipitation records for northern China, we found that widespread and severe droughts occurred at ca. 4.3–3.4 cal ka BP, and 1.5–0.8 cal ka BP due to decreased monsoon rainfall, which closely corresponds to the expansion of Arctic sea ice and the weakening of Atlantic Meridional Overturning Circulation. Additionally, the most widespread and severe drought occurred at the period 1.5 to 0.8 cal ka BP in northern China, possibly linked with the expansion of sea ice in the North Atlantic. Importantly, the intensity of droughts resulting from the weakened summer monsoon circulation in northern China increases with latitude. In the current warm period, the spring water depth of Daihai Lake has reached its lowest level since the late Holocene, likely due to the enhanced evaporation resulting from climate warming. These findings suggest that, under the influence of ongoing global warming, spring drought, along with lake shrinkage and salinization in northern China, may intensify.
了解过去干旱的演变和机制可以为全球变暖背景下的中国北方干旱预测提供重要的见解。全新世晚期，中国北方干旱频繁；然而，其空间格局和强度却很少受到关注。本文以内蒙古代海为例，分析了代海在全新世后期春季水体深度的长期下降趋势。值得注意的是，在约4.3 ~ 3.4 cal ka BP、2.5 ~ 2.2 cal ka BP、1.5 ~ 0.8 cal ka BP和当前暖期，水体深度显著减少。结合已发表的中国北方降水重建记录，我们发现在约4.3 ~ 3.4 cal ka BP和1.5 ~ 0.8 cal ka BP期间，由于季风降水减少，发生了广泛而严重的干旱，这与北极海冰的扩张和大西洋经向翻转环流的减弱密切相关。此外，中国北方地区在1.5 ~ 0.8 cal ka BP期间出现了最广泛和最严重的干旱，这可能与北大西洋海冰的扩张有关。重要的是，中国北方夏季风环流减弱导致的干旱强度随纬度增加而增加。在当前暖期，代海的泉水深度达到了晚全新世以来的最低水平，这可能是由于气候变暖导致蒸发加剧所致。这些结果表明，在持续的全球变暖的影响下，中国北方春季干旱以及湖泊萎缩和盐碱化可能加剧。
{"title":"The intensity of the late Holocene drought in northern China related to Arctic Sea ice","authors":"Jiaju Zhao , Qianwen Zhang , Zhongwei Shen , Zhiping Zhang , Jie Chen , Lin Chen , Jinzhao Liu , Yunning Cao , Jing Hu","doi":"10.1016/j.gloplacha.2026.105300","DOIUrl":"10.1016/j.gloplacha.2026.105300","url":null,"abstract":"<div><div>Understanding the evolution and mechanisms of past droughts can provide critical insights for drought prediction in northern China in the context of global warming. During the late Holocene, drought was frequently in northern China; however, its spatial patterns and intensities have received less attention. Here, we present a high-resolution moisture record based on alkenone proxies from Daihai Lake (Inner Mongolia, China), which indicates a long-term decline in water depth in spring during the late Holocene. Notably, significant reductions in water depth were observed during the periods of ca. 4.3–3.4 cal ka BP, 2.5–2.2 cal ka BP, 1.5–0.8 cal ka BP, and the current warm period. In conjunction with published reconstructed precipitation records for northern China, we found that widespread and severe droughts occurred at ca. 4.3–3.4 cal ka BP, and 1.5–0.8 cal ka BP due to decreased monsoon rainfall, which closely corresponds to the expansion of Arctic sea ice and the weakening of Atlantic Meridional Overturning Circulation. Additionally, the most widespread and severe drought occurred at the period 1.5 to 0.8 cal ka BP in northern China, possibly linked with the expansion of sea ice in the North Atlantic. Importantly, the intensity of droughts resulting from the weakened summer monsoon circulation in northern China increases with latitude. In the current warm period, the spring water depth of Daihai Lake has reached its lowest level since the late Holocene, likely due to the enhanced evaporation resulting from climate warming. These findings suggest that, under the influence of ongoing global warming, spring drought, along with lake shrinkage and salinization in northern China, may intensify.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"258 ","pages":"Article 105300"},"PeriodicalIF":4.0,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145962394","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}
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