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Ice coverage not only affects the climate and landscape of geographical regions but has impacted species composition, the fragmentation and isolation of populations, and the colonisation routes of species post-glaciation. Major advancements in generating genetic data and applying sophisticated analyses to accurately model the demographic and colonisation history of animal and plant species has allowed evolutionary biologists novel insights. Meanwhile, physical geographers have made major advancements in reconstructing glacial history. However, the information flow between the geographic and evolutionary fields on this topic remains limited; consequently, evolutionary studies on contemporary biodiversity and species colonisation tend to be vague about the role of glacial history, while evolutionary and biodiversity information is rarely leveraged when discussing historical glaciation. In this review, we bring together current knowledge on the changing patterns of ice coverage in the British Isles from the maximum extent of the British-Irish ice sheet (BIIS) ca. 27 ka through to the end of large-scale ice coverage at the start of the Holocene period ca. 11.5 ka. We do so to then highlight how glaciation affected species composition during this time period and the subsequent colonisation of temperate flora and fauna and the patterns of genetic variation seen in them. [ABSTRACT FROM AUTHOR]

This study analyzed the macro- and microphysical response characteristics of a typical multicell hailstorm after seeding on 27 April 2019 in Weining, China, using X-band dual-polarization radar (YLD1-D) data. An improved X-pol hydrometeor identification algorithm was employed for hydrometeor identification. According to the diffusion of the seeding agents, the seeded hailstorm was graded into three study regions, and the evolution of the seeded hailstorm was divided into four periods. The response characteristics of the seeded hailstorm in each region and period were compared and analyzed. The results show that 1) macroscopically, the decrease in the reflectivity and the height of strong echo mainly occurred in the seeded period, whereas the decrease in the echo top and the height of the storm was mainly in the postseeded period; the echo height variation of the unseeded hailstorm is obviously different from that of the seeded hailstorm; and 2) from the microscopic perspective, the decrease in low-density graupel and supercooled water and the increase in ice crystals and aggregates in the seeded region mainly occurred in the seeded period, which was consistent with the time required for the "benefit competition" after the silver iodide completed nucleation. When compared with the seeded region, the hydrometeors in the unseeded region had an opposite trend (or an in-phase trend with an obviously lower changing rate), which further indicated the impact of the artificial ice nuclei on microphysical processes in the seeded region. For hailstorms with a high content of supercooled droplets and graupel, the key mechanisms of hail suppression are "cloud water glaciation," "beneficial competition," and "early rainout." [ABSTRACT FROM AUTHOR]

The results of U–Pb (ID-TIMS) and U–Th–Pb (LA-ICP-MS) geochronological studies of baddeleyite from dolerite dikes of the Sulumat Complex and detrital zircon from red arkose sandstones of the Kebekta Group of the Ugui graben, Aldan Shield, are presented. It has been established that the Kebekta Group has an age of 2.01–1.87 Ga. The provenance areas of the Kebekta Group deposits were the Archean (2.92–2.52 Ga) igneous and metamorphic complexes of the Chara–Olekma Geoblock and the zone of its junction with the Western Aldan Megablock of the Aldan Shield, as well as the Paleoproterozoic (approximately 2.01 Ga) complexes unidentified on the present erosion level. The obtained geochronological data do not contradict the correlation of terrigenous rocks of the Kebekta Group of the Ugui graben and the Kemen Group of the Kodar–Udokan trough. The deposition of arkose sandstones of the Kebekta Group correlates in age with the glaciations in Australia and Sweden (approximately 1.9–1.8 Ga) associated with the formation of the Columbia/Nuna supercontinent. It cannot be excluded either that the deposition of the rocks in the Ugui graben was related to the inflow of glacial material into the intracontinental extensional basin from the southern and/or western (in modern coordinates) framing of the Chara–Olekma Geoblock at the stage of collapse of the Paleoproterozoic orogen. [ABSTRACT FROM AUTHOR]

The White River Badlands (WRB) of South Dakota record eolian activity spanning the late Pleistocene through the latest Holocene (21 ka to modern), reflecting the effects of the last glacial period and Holocene climate fluctuations (Holocene Thermal Maximum, Medieval Climate Anomaly, and Little Ice Age). The WRB dune fields are important paleoclimate indicators in an area of the Great Plains with few climate proxies. The goal of this study is to use 1 m/pixel-resolution digital elevation models from drone imagery to distinguish Early to Middle Holocene parabolic dunes from Late Holocene parabolic dunes. Results indicate that relative ages of dunes are distinguished by slope and roughness (terrain ruggedness index). Morphological differences are attributed to postdepositional wind erosion, soil formation, and mass wasting. Early to Middle Holocene and Late Holocene paleowind directions, 324°± 13.1° (N = 7) and 323° ± 3.0° (N = 19), respectively, are similar to the modern wind regime. Results suggest significant landscape resilience to wind erosion, which resulted in preservation of a mosaic of Early and Late Holocene parabolic dunes. Quantification of dune characteristics will help refine the chronology of eolian activity in the WRB, provide insight into drought-driven landscape evolution, and integrate WRB eolian activity in a regional paleoenvironmental context. [ABSTRACT FROM AUTHOR]

China is a crucial region for investigating the relationship between climate change and hominin evolution across diverse terrestrial ecosystems. With the continuous development of palaeoclimatology, chronology, and archaeology, the environmental and hominin record of the Early and Middle Pleistocene in China is steadily accumulating, shedding light on the effects of climate change on the distribution of early human settlements and population dynamics. However, the migration and dispersal of these early humans within long-term climate fluctuations and their underlying mechanisms remain to be clarified. Based on the spatial-temporal distribution of 95 Early to Middle Pleistocene archaeological sites in China, we found that intensified hominin activities gradually shifted southward under the influence of multiple glacial–interglacial cycles. The frequent bidirectional movements of these early humans between north and south were assumed as follows. During glacial periods, hominins living in North China migrated to southern areas, while inter-glacial periods witnessed the northward expansion of hominins inhabiting South China. Among all the potential driving mechanisms, we suggest that the available resources in terrestrial ecosystems may be the most fundamental factor. Combined with paleoenvironmental and archaeological records, we provide an Asian perspective for a better understanding of how the glacial–interglacial cycles shaped early human evolution. [ABSTRACT FROM AUTHOR]

Well-preserved Quaternary sedimentary sequences in the central coast of Ecuador have provided sufficient relevant information for paleogeographic reconstruction and climatic evolution, from stratigraphic, geochemical, and biological analysis. The Jaramijo canton site is one of the most remarkable results in the stratigraphic correlation of lithological units with delineation of a paleo sea-cliff of age 14C 43,245 ± 460 B.P. (belonging to the MIS-3). This MIS-3 is associated with a period of glaciation, but the data obtained, such as δ 18O, indicate paleo-temperature values of −1 to −1.5, which are interpreted in this study, indicate that the central coast of Ecuador has an interstadial phase (warm years in a glacial stage). Two more paleo-coastal cliffs have been mapped from orthophoto analysis, but these are younger. The sedimentary levels analyzed in this study include deposits that occurred in MIS 3 to MIS 1. Holocene transgression has modified the central coast of Ecuador and increased the level of coastal climate hazard by sea level rise. Indeed, paleo-coastlines have been evidenced from bathymetric data in the depth contours of −5.5 m and −7.6 m, at 440 and 650 m distances from the up-to-date coastline. For the Jaramijó site, the rate of cliff-erosion and wave-cut platforms are in the order of 1.1 to 2.4 m/yr. These cliff-erosion rates, with a moderate to high coastal vulnerability index, can be increased if we consider mathematical models with an estimated sea-level rise scenario to be, in 2100, about +1 to +1.4 m. [ABSTRACT FROM AUTHOR]

Holarctic species offer great opportunities to study biogeography, phylogenetics, taxonomy, and local adaptation. Species that are considered conspecific between the Palearctic and the Nearctic realms are often split into 2 or more species when denser sampling and molecular markers are applied. Similar in complexity but at a finer geographical scale are species groups having Arctic-Alpine distributions where lineages have complicated demographic histories due to glacial dynamics. In both cases, allopatric speciation might not result in fast differentiation of morphological characters if environmental conditions in isolated areas are similar and the main driver of variability is genetic drift. Here, we study the Holarctic Pardosa hyperborea (Thorell, 1872) and its closest European relatives to assess their taxonomic status and patterns of genetic variability. Based on DNA barcodes and genomic data from double-digest restriction site associated sequencing, we propose that the North American populations should be regarded as a distinct species (P. luteola Emerton,1894, stat. resurr.), possibly consisting of several independent lineages. With the help of D-statistics, population genetic simulations and phylogenetic networks analysis, we demonstrate historical introgression among European species of the group and a likely explanation for shared DNA barcodes among allopatric and fully differentiated species. Our study exposes a promising model for studying speciation processes and demographic history in parallel on both sides of the Atlantic Ocean and demonstrates the usefulness of genomic tools in elucidating the taxonomy and biogeography of taxa across broad geographic scales. [ABSTRACT FROM AUTHOR]

The investigation of deformations in Quaternary deposits holds primary importance in understanding recent geological history and natural hazards in highly populated areas, such as the Po Plain. While civil excavations and trenches possess the potential to be pivotal in identifying and characterizing these deformations, they often remain underused due to the stringent regulation framework and timetables governing civil construction works. In this study, we demonstrate how digital photogrammetry and digital outcrop modelling (DOM) are useful techniques for obtaining a permanent digital representation of a trench situated in Castelletto Ticino (Po Plain–Southern Alps transition). This trench exhibits Holocene deformational structures: (i) an overall tilting of sedimentary deposits towards the SW; (ii) folds with a NE–SW trend; (iii) slumping and other soft-sediment deformations structures; and (iv) reverse faults with NE–SW and NW–SE directions. Using radiocarbon and archeological dating, we are able to confidently constrain the age of these deformations to between 8760 and 400 years BC, suggesting recent tectonic activity related to buried thrust faults. [ABSTRACT FROM AUTHOR]

Quantifying variability in, and identifying the mechanisms behind, East Asian dust production and transport across the last several million years is essential for constraining future dust emissions and deposition. Our current understanding of East Asian dust dynamics through the Quaternary is primarily limited to low‐resolution records from the North Pacific Ocean, those from the Chinese Loess Plateau (CLP), and paleoenvironmental reconstructions from arid basins. All are susceptible to sediment winnowing and focusing as well as input of poorly constrained or unidentified non‐dust detrital material. To avoid these limitations, we examine high‐resolution, constant flux proxy‐derived dust fluxes from the North Pacific and find evidence for higher glacial dust fluxes in the late Pliocene‐early Pleistocene compared to the late Pleistocene‐Holocene. Our results suggest decreasing dust transported to the mid‐latitude North Pacific Ocean from eastern Asia across the Quaternary. This observation is ostensibly at odds with previous dust records from marine sediments and the CLP, and with the perception of higher East Asian dust production and transport during the late Pleistocene associated with the amplification of glaciations. We provide three possible scenarios to describe the ∼2,700‐ky evolution of eastern Asia glacial dust dynamics, and discuss them in the context of sediment production, availability, and atmospheric circulation. Our data and proposed driving mechanisms not only raise questions about the framework typically used to interpret dust archives from East Asia and the North Pacific Ocean, but also provide a roadmap for hypothesis testing and future work necessary to produce better‐constrained records of paleo‐dust fluxes. Key Points: Constant flux proxy‐derived glacial dust fluxes to the North Pacific decrease between the early and late QuaternaryReduced glacial dust fluxes may be a result of shifting dust production dynamics and/or atmospheric circulationChinese Loess Plateau accumulation rates may need to be reevaluated when considered for paleoclimate reconstructions [ABSTRACT FROM AUTHOR]

Pleistocene climate oscillations had a dramatic impact on the distribution of temperate ectothermic organisms. These range fluctuations plausibly have left a footprint on the species' genetic structure which is linked with modelled paleoclimatic conditions, allowing us to infer which environmental factors shaped the evolutionary history of Sand lizards. In this study, we evaluated the patterns of niche diversification of Lacerta agilis in Eurasia, based on mitochondrial DNA analyses and ecological niche models. The lineage of Sand lizards evolved 3.8-1.8 Mya, being the most basal in the east-Caucasian subclade, with eight mitochondrial subclades separated into two groups. These groups represent two independent waves of expansion from the ancestral region constituted by the Caucasus and the adjacent northern plains to the Paleartic. Paleoclimatic models suggested a high instability of the range of this lineage in the last 3 Mya, with niche contractions during the colder glacial periods and expansions following the glacier retreat. This suggested an allopatric diversification process, with subspecies boundaries upon secondary contact maintained by competitive interactions, at least between closely related pairs. The great mountain systems of the Mediterranean Peninsulas constituted stable refugia during the Pliocene-Pleistocene cycles, favouring the evolution of endemic subclades. These montane subclades have higher mitochondrial diversity than those that occur in the plains. However, the Pyrenean endemic L. agilis garzoni is exception possibly due to the occupation of a very small refugium during the recent glacial phases. [ABSTRACT FROM AUTHOR]

The oldest known hominin remains in Europe [~1.5 to ~1.1 million years ago (Ma)] have been recovered from Iberia, where paleoenvironmental reconstructions have indicated warm and wet interglacials and mild glacials, supporting the view that once established, hominin populations persisted continuously. We report analyses of marine and terrestrial proxies from a deep-sea core on the Portugese margin that show the presence of pronounced millennial-scale climate variability during a glacial period ~1.154 to ~1.123 Ma, culminating in a terminal stadial cooling comparable to the most extreme events of the last 400,000 years. Climate envelope-model simulations reveal a drastic decrease in early hominin habitat suitability around the Mediterranean during the terminal stadial. We suggest that these extreme conditions led to the depopulation of Europe, perhaps lasting for several successive glacial-interglacial cycles. [ABSTRACT FROM AUTHOR]

The continuous ice core record extends 800,000 years into the past, covering the period of 100,000-year glacial cycles, but not the transition from 40,000-year glacial cycles (the Mid-Pleistocene Transition, 1.2–0.7 million years ago). A primary goal of the International Partnership in Ice Core Sciences is therefore to retrieve a 1.5-million-year-old continuous ice core, increasing our understanding of this major change in the climate system and thus of fundamental climate forcings and feedbacks. However, complex glacial processes, limited bedrock data, and surprisingly young basal ice in previous cores necessitate careful reconnaissance studies before extracting a full core. Ice borehole optical logging reflects the ice dust content and may be used to date ice quickly and inexpensively if a reference record is known. Here we explore the relationship between ice dust records and well-dated marine dust records from sediment cores in the southern Atlantic and Pacific Oceans, which lie along paths of dust sources to Antarctica. We evaluate how representative these records are of Antarctic dust both through the existing ice core record and during the older target age range, suggesting that a newly published 1.5 million year record from site U1537 near South America is likely the most robust predictor of the Oldest Ice dust signal. We then assess procedures for rapid dating of potential Oldest Ice sites, noting that the ability to detect dating errors is an essential feature. We emphasize that ongoing efforts to identify, recover, date, and interpret an Oldest Ice core should use care to avoid unfounded assumptions about the 40 kyr world based on the 100 kyr world. [ABSTRACT FROM AUTHOR]

Simple Summary: The Siberian ibex has a wide distribution, spanning various mountainous regions and cold deserts in countries like India, China, Pakistan, Kazakhstan, Tajikistan, Russia, and Mongolia. Our study specifically examined the Himalayan ibex, which is an edge population of Siberian ibex found in India. Through genomic analysis, we discovered that the Himalayan ibex evolved as a distinct lineage after separating from the main population around 100,000 years ago, due to geographical isolation. By studying the region's past geography using paleo-climatic models and deep sequencing data, we observed significant transformations, including high mountains and deep valleys, particularly in the Pamir range, likely played a significant role in the divergence and independent evolution of the Himalayan ibex, after experiencing two historic genetic bottlenecks. Based on our findings, we propose prioritizing the Himalayan ibex as a unique phylogenetic species and advocate for its conservation attention and taxonomic revision. Furthermore, we hope that our research will inspire collaborative efforts and discussions among different countries to address the conservation and management of ibex populations worldwide. Pleistocene glaciations had profound impact on the spatial distribution and genetic makeup of species in temperate ecosystems. While the glacial period trapped several species into glacial refugia and caused abrupt decline in large populations, the interglacial period facilitated population growth and range expansion leading to allopatric speciation. Here, we analyzed 40 genomes of four species of ibex and found that Himalayan ibex in the Pamir Mountains evolved independently after splitting from its main range about 0.1 mya following the Pleistocene species pump concept. Demographic trajectories showed Himalayan ibex experienced two historic bottlenecks, one each c. 0.8–0.5 mya and c. 50–30 kya, with an intermediate large population expansion c. 0.2–0.16 mya coinciding with Mid-Pleistocene Transitions. We substantiate with multi-dimensional evidence that Himalayan ibex is an evolutionary distinct phylogenetic species of Siberian ibex which need to be prioritized as Capra himalayensis for taxonomic revision and conservation planning at a regional and global scale. [ABSTRACT FROM AUTHOR]

Glacial diamictite may provide important information on paleoenvironment and average composition of the upper continental crust (UCC). In this study, we report sedimentary facies, petrological and geochemical characteristics of Neoproterozoic diamictite from a profile of the Luoquan Formation on the southern margin of the North China Block (NCB). Upwards the sampling profile, lithostratigraphic strata vary from massive diamictite with poorly sorted carbonate gravels to laminated diamictite with small gravels of terrestrial detrital materials. Along the profile, CaO-MgO-LOI-Sr values decrease with the increase of SiO2-Al2O3-K2O contents. All these petrological and geochemical variations indicate a change from lodgement till deposition in the proximal of ice sheet to ice-rafting deposition in glacial-marine environment with less dolomite to supply their source. Together with previous studies on diamictite from other outcrops on the NCB, the deposition of Luoquan diamictite reflects that the glaciation on the NCB vanished and the ice-rafting effect weakened with glacial transgression process. In addition, significant co-variations of various elements with La and Al2O3 confirm the significant conservation of most analyzed elements during the sedimentary processes to produce diamictite. [ABSTRACT FROM AUTHOR]

At the end of the last glacial period in the northern hemisphere, meltwater from receding ice sheets accumulated into large proglacial lakes, potentially limiting postglacial afforestation. We explored whether former islands of proglacial Lake Ojibway (Canada) (hilltops in the current landscape) could have acted as migration outposts and thus accelerated the postglacial migration. We extracted sediments from two small lakes located on "paleo-islands" and used XRF to detect changes in soil erosion and vegetation biomass. We also used plant macro-remains and wood charcoal to determine if (and which) tree species colonized the sites and to detect local fire events. Organic sediment accumulation started around 9657 and 9947 cal. yr BP at Lakes Perché and Despériers, respectively, before the level of Lake Ojibway started to decrease and liberate parts of the studied landscape ca 9400 cal. yr BP. Lithogenic elements (Ti, K, Sr, Fe, Zr, and Rb) decreased between the beginning of organic sediment accumulation and 8800–8700 cal. yr BP, indicating reduced soil erosion, possibly due to soil stabilization by vegetation. Then, the S/Ti ratio, a proxy of organic matter increased around 8800 and 8400 cal. yr BP. The earliest tree macro-remains (Larix laricina and Pinus spp.) were found between 9850 and 9500 cal. yr BP. Local fires were detected around 9820 and 8362 cal. yr BP. Early afforestation occurred on the islands of Lake Ojibway, 200 and 450 years before its level started to decrease, confirming that some islands acted as migratory outposts accelerating postglacial migration. [ABSTRACT FROM AUTHOR]

Vertically accreted, cyclic tidal rhythmites—laminated, fine-grained sandstones, siltstones and mudstones—occur in the late Cryogenian glaciogenic Elatina Formation (ca 635 Ma) and early Cryogenian Sturt Formation (ca 660 Ma) in the South Flinders Ranges region of the Adelaide Rift Complex within the Adelaide Superbasin, and in Cryogenian strata from Nicholson 2 drill hole in the eastern Officer Basin, South Australia. The rhythmites provide insights into Cryogenian littoral environments. The Elatina rhythmite was deposited during an interstadial and the Sturt rhythmite during early glacial advance, whereas the Nicholson 2 rhythmite is assigned to interglacial beds. The resultant raised sea levels and drowned valleys provided the tidal inlets, ebb-tidal deltas, estuaries and fjords favouring rhythmite deposition. The rhythmites display semidiurnal and diurnal (lunar day) tidal laminae grouped in fortnightly neap–spring cycles and record the semiannual tide. Periods of 26.2 ± 0.9 neap–spring cycles displayed by the Elatina rhythmite and ∼27 neap–spring cycles by the Nicholson 2 rhythmite mark the non-tidal annual variation of sea level, which results from seasonal surface winds and changes in atmospheric pressure and temperature acting on the waters of marine shelves and marginal seas. The strong annual signals and absence of dropstones in the Elatina and Nicholson 2 rhythmites indicate that respective marine shelves and marginal seas were ice-free during rhythmite deposition. The Sturt rhythmite, by contrast, shows a weak annual period of ∼27 neap–spring cycles and contains dropstones and till pellets, indicating that the adjacent marine shelf and sea were largely ice-covered. Paleotidal data for the Elatina rhythmite have illuminated Earth's late Cryogenian paleorotation and the Moon's orbit, and paleomagnetic studies of the Elatina rhythmite indicated a low paleolatitude for late Cryogenian glaciation. Contrary to recent modelling by others, strong tides existed at shallow-water continental margins during Cryogenian glaciations. Cyclic tidal rhythmites are associated with early and late Cryogenian (ca 660 and ca 635 Ma) glaciogenic successions and interglacial beds in South Australia. Rhythmite deposition occurred when raised sea levels provided the coastal environments favouring rhythmite deposition. The rhythmites display semidiurnal and diurnal tidal laminae grouped in fortnightly cycles, and record the semiannual tide and the non-tidal annual variation of sea level. Strong tides existed at shallow-water continental margins during early and late Cryogenian low-latitude glaciations and the interglacial interval. [ABSTRACT FROM AUTHOR]

Recent observations confirm the Indo-Pacific Little Tern Sternula albifrons sinensis has been extending its breeding range in Western Australia in recent years, following a pattern documented in other tern and noddy species on the western coast of Australia. Nesting Indo-Pacific Little Terns have been recorded annually as far south as North West Cape since 2016. A similar southward shift in breeding range may have occurred during the last interglacial period and it is hypothesised that Little Terns isolated at the Houtman Abrolhos Islands during the following glacial period gave rise to the Australian Fairy Tern Sternula nereis nereis. The Australian Fairy Tern subsequently colonised the continental shelf from Dampier, Western Australia to the south-eastern states and then New Zealand as sea levels rose again during the Holocene. The two former sibling species are now sympatric between Dampier and North West Cape and interbreeding and hybridisation have the potential to occur in that area. Most jurisdictions require populations to be defined at the species or subspecies level in order to be listed and managed as threatened. However, relying on such taxonomic criteria has the potential to obscure the management of threats faced by each inter-breeding population unit. Approaches that identify and protect the sub-structure of superspecies and meta-populations might be more effective in the longer term. This contribution documents a breeding range extension of the Indo-Pacific Little Tern Sternula albifrons sinensis in Western Australia, following a pattern documented in other tern and noddy species. It also discusses the overlap and relationship with the closely related Australian Fairy Tern Sternula nereis nereis and relevant conservation implications. [ABSTRACT FROM AUTHOR]

This paper addresses the effect of fractures within crystalline bedrock on glacial erosion processes in fast flowing hard bed glacier environments. In particular, we examine (i) whether the fracture type is critical for the capability of a glacier to erode the bedrock through quarrying/plucking processes and (ii) whether we can recognize specific fracture‐controlled erosion signatures from bedrock surface morphologies. We conducted an investigation within the northern part of the Åland Islands, southern Finland, where the ice‐flow direction (N–S) has remained constant through Late Pleistocene glaciations and where the bedrock is characterized by a lack of any mesoscopic anisotropies (such as foliation) and hence provides an optimal target to recognize the relationships between fractures and erosional morphologies. We characterized the fracture systems within the bedrock using both UAV‐acquired orthophotographs and standard field approaches and extrapolated the results to larger scales using LiDAR‐based digital elevation models. Our findings indicate that individual joints or shear fractures are associated with the development of minor vertical breaks along the bedrock surface. However, they do not provide sufficient mechanical weakness zones in the bedrock to allow effective glacial quarrying, even though their lengths can be relatively large (>50 m). By contrast, the linkage of several parallel shear fractures or the presence of larger faults with gouge‐bearing cores and well‐developed damage zones leads to localized disintegration of the rock material and the subsequent development of distinct topographic depressions along the bedrock surface. Consequently, the results allow predictions to be made about the bedrock features underlying the observed topographic signatures along the bedrock surface. Applied to the area of this investigation, abrasion associated with N–S‐directed glacial flows is responsible for the N–S‐oriented elongate but smooth fjord‐like megagrooves, whereas the more abrupt topographic breaks were generated by quarrying controlled by sub‐vertical, E–W‐trending zones of localized brittle deformation. [ABSTRACT FROM AUTHOR]

Understanding the temporal‐spatial patterns of modern and relict sediments is of importance for assessing changes in the Quaternary environment and sea‐level. Sedimentological and geochemical data is presented, along with in situ shell‐based accelerator mass spectrometry 14C ages of 30 samples from the surface sediments on the northern shelf of the South China Sea (NSSCS). The authors' data show that the NSSCS surface sediments exhibit considerable diversity in composition. Modern sediments are primarily constrained to the NW inner shelf, which is fed by fluvial sands sourced from Coastal South China river systems and dominated by the Pearl River Estuary delivery. The transport and discharge of the terrestrial sediments to the NSSCS is highly influenced by the Guangdong Longshore Current and its secondary cyclonic eddies. Relict sediments dominated by well‐sorted, medium‐ and coarse‐grained sands were identified in the NW Shenhu and NW Dongsha areas of the outer NSSCS. The sedimentology and geochemistry of the relict sediments imply that they were deposited in a dry and cold environment either during the low sea levels of the late Pleistocene (∼40 ka) or the early Holocene (∼10 ka). To the east, the Taiwan Shoal and vicinity are dominated by a sand mixture, at which the relict sediments were reworked by terrigenous supply and modern hydrodynamic environment due to the compound action of the Guangdong Longshore Current, seasonal cyclones, and Kuroshio Intrusion. The present isobaths of ∼−90 m in the NSSCS might be the reflective of the early Holocene coastal delta or the last glacial maximum shoreline. Plain Language Summary: Reconstructing the temporal‐spatial pattern for relict sediments in shelf environments is an important way of determining the shoreline or coastal delta position during the late glacial period or the early Holocene. The largest and longest zone of the relict sediments has been traditionally suggested to be along the outer shelf of the East Asian continental margin from Malaya to Korea across the NSSCS. However, less attention has been paid to the NSSCS relict sediments despite the fact that much research has documented the sediment supply, Holocene environment, and marine resource surveys. The authors' data revealed the development of the modern sediments in the NW inner shelf and the relict sediments in the NW Shenhu and NW Dongsha areas of the NSSCS outer shelf. The relict sediments were sourced from Coastal South China and SW Taiwan, and have a distinct depositional environment in comparison with that of the modern sediments. The temporal‐spatial pattern of the relict sediments suggests that the current ca. −90 m isobaths were close to the shoreline or coastal delta at the last glacial period or the early Holocene. Key Points: The modern sediments preserved on the NW inner shelf of the northern South China Sea are heavily influenced by the Guangdong Longshore CurrentRelict sediments characterized by well‐sorted, medium‐ and coarse‐grained sands dominated the NW Shenhu and Dongsha areasThe −90 m isobaths in the NSCS are in close proximity to the last glacial maximum shoreline or northern limit of the early Holocene coastal delta [ABSTRACT FROM AUTHOR]

Pollen reconstructions of tree genera in North America since glaciation are available, but species distributions predicted for paleoclimate based on tree inventories may inform knowledge gaps. Here I examined the distributions of 25 species or species groups from 20 000 years ago (ka) to 5 ka to give potential paleoecological ranges of boreal and temperate tree species. I also assessed the effects of correlated climate variables on species distribution models for current and past climate, which were modeled with the non‐linear random forests classifier. Climate change alone was enough to create unique, species‐specific paths that did not run directly north. At 20 ka, black spruce (Picea mariana) occurred as far north as the ice sheet and most boreal species generally may have extended as far south as 32°N, or the northern southeastern United States. Temperate eastern species may have extended as far north as 39°N in low‐elevation locations and temperate eastern species displayed both continuous and clustered distributions across the southeastern United States. Rate of movement was 5.5 km per century between 20 and 14 ka, 13.3 km per century between 14 and 10 ka, and 3.25 km per century between 10 and 5 ka. Species retreated southward between 7 and 5 ka. Regarding correlation, models with all variables had greater accuracy than models with the two most important variables, which had greater accuracy than models with two variables of intermediate importance, demonstrating both reduced accuracy with omission of relevant variables and isolation of important variables that improve accuracy in models with correlated climate variables. Models from different climates identified the same two most important variables and ranked the remaining variables similarly, revealing robustness in the models over time. Distribution models agreed with pollen reconstructions regarding timing and rate of change, while generating detailed species‐specific information about movement trajectories and velocities, latitudinal extents, and distribution continuities. [ABSTRACT FROM AUTHOR]

Reconstructions of palaeo‐sea level are vital for predicting future sea level change and constraining palaeo‐ice sheet reconstructions, as well as being useful for a wide array of applications across Quaternary Science. Previous reconstructions of the palaeo‐sea level of Britain and Ireland relied on a circular tuning of glacio‐isostatic models: input ice sheet thicknesses and extents were iteratively altered to fit relative sea level data. Here we break that circularity by utilizing new data from the BRITICE‐CHRONO project, which constrains the position of the British–Irish ice sheet margin through time, and we compare derived glacio‐isostatic modelling to the rich relative sea level record. We test a combination of plausible ice thickness scenarios which account for the uncertainty of ice margin position over the North Sea, demonstrating the region where regional sea level data could distinguish between different glaciation scenarios. Our optimal reconstruction is then combined with several global‐scale reconstructions. As the signal of the British–Irish Ice Sheet is constrained, we demonstrate how the relative sea level record of Britain and Ireland can be used to test reconstructions of far‐field ice sheets (e.g. Antarctica, Eurasia and the Laurentide). The derived palaeo‐topography data are likely to be useful for multiple disciplines. Finally, our improved method of sea level reconstruction impacts predictions of contemporary vertical land motion. [ABSTRACT FROM AUTHOR]

The Marine20 radiocarbon (14C) age calibration curve, and all earlier marine 14C calibration curves from the IntCal group, must be used extremely cautiously for the calibration of marine 14C samples from polar regions (outside ∼ 40ºS–40ºN) during glacial periods. Calibrating polar 14C marine samples from glacial periods against any Marine calibration curve (Marine20 or any earlier product) using an estimate of ${\rm{\Delta R}}$ , the regional 14C depletion adjustment, that has been obtained from samples in the recent (non-glacial) past is likely to lead to bias and overconfidence in the calibrated age. We propose an approach to calibration that aims to address this by accounting for the possibility of additional, localized, glacial 14C depletion in polar oceans. We suggest, for a specific polar location, bounds on the value of ${\rm{\Delta }}{{\rm{R}}_{20}}\left({\rm{\theta }} \right)$ during a glacial period. The lower bound ${\rm{\Delta R}}_{20}^{{\rm{Hol}}}$ may be based on 14C samples from the recent non-glacial (Holocene) past and corresponds to a low-depletion glacial scenario. The upper bound, ${\rm{\Delta R}}_{20}^{{\rm{GS}}}$ , representing a high-depletion scenario is found by increasing ${\rm{\Delta R}}_{20}^{{\rm{Hol}}}$ according to the latitude of the 14C sample to be calibrated. The suggested increases to obtain ${\rm{\Delta R}}_{20}^{{\rm{GS}}}$ are based upon simulations of the Hamburg Large Scale Geostrophic Ocean General Circulation Model (LSG OGCM). Calibrating against the Marine20 curve using the upper and lower ${\rm{\Delta }}{{\rm{R}}_{20}}$ bounds provide estimates of calibrated ages for glacial 14C samples in high- and low-depletion scenarios which should bracket the true calendar age of the sample. In some circumstances, users may be able to determine which depletion scenario is more appropriate using independent paleoclimatic or proxy evidence. [ABSTRACT FROM AUTHOR]

The Eocene-Oligocene transition (ca 40–33 Ma) marks a transformation from an ice-free to an ice-house climate mode that is well recorded by oxygen stable isotopes and sea surface temperature proxies. Opening of the Southern Ocean gateways and decline in atmospheric carbon dioxide have been hypothesised as possible triggers of the major climate shift during the Cenozoic. However, identifying the driving mechanisms remains controversial and depends on a better understanding of how the different environmental changes correlate. In this study, we investigate the spatio-temporal variation in export productivity using biogenic Ba (bio-Ba) from different Ocean Drilling Program (ODP) Sites in the Southern Ocean, focusing on possible mechanisms that controlled them as well as the correlation of export productivity changes to changes in the global carbon cycle. We document two significant SO region high export productivity late-Eocene events (ca. 37 and 33.5 Ma) correlated to pronounced changes in global atmospheric p CO2. We propose that paleoceanographic changes that followed Southern Ocean gateway openings, along with more variable increases in circulation driven by episodic expansion and decline of the Antarctic ice sheet, drove enhanced SO export production in the late Eocene through basal Oligocene. These factors may have driven the episodic reduction of atmospheric carbon dioxide and contributed to Antarctic glaciation during the Eocene-Oligocene transition. [ABSTRACT FROM AUTHOR]

The trigger, pace, and nature of the intensification of Northern Hemisphere Glaciation (iNHG) are uncertain, but can be probed by study of ODP Site 1208 North Pacific marine sediments. Herein, we present magnetic proxy data that indicate a 4-fold increase of dust between ~ 2.73 and ~ 2.72 Ma, with subsequent increases at the start of glacials thereafter, indicating a strengthening of the mid-latitude westerlies. Moreover, a permanent shift in dust composition after 2.72 Ma is observed, consistent with drier conditions in the source region and/or the incorporation of material which could not have been transported via the weaker Pliocene winds. The sudden increase in our dust proxy data, a coeval rapid rise in dust recorded by proxy dust data in the North Atlantic (Site U1313), and the Site 1208 shift in dust composition, suggest that the iNHG represents a permanent crossing of a climate threshold toward global cooling and ice sheet growth, ultimately driven by lower atmospheric CO2. The amount and composition of North Pacific dust tracked by rock magnetism suggests that the intensification of North Hemisphere Glaciation ca. 2.7 million years ago marked the permanent crossing of a climate threshold. [ABSTRACT FROM AUTHOR]

The Pliensbachian–Toarcian transition was characterised by a drastic turnover from a cool climate to a period of rapid global warming. While the warming associated with the Early Toarcian Oceanic Anoxic Event is rather well-studied, the cause, intensity and extent of the preceding cooling in the late Pliensbachian are still discussed. Occurrences of glendonite play an important role in this debate, since glendonite is a pseudomorph after the cryophilic carbonate mineral ikaite. This study describes the first glendonite-bearing carbonate concretions from South Germany (Buttenheim clay pit, northern Franconian Alb), which represent the southernmost glendonite occurrence in the late Pliensbachian documented so far. Based on petrographical and sedimentological investigations as well as stable isotope analyses it is concluded that a low temperature was the main factor for ikaite formation in the studied section, suggesting that the late Pliensbachian cooling had a more far-reaching impact on the temperature of the European epicontinental sea than previously assumed. To explain the low temperatures required for ikaite precipitation, a model for the sea-ice driven formation of cold bottom-water masses on the continental shelf is proposed. The occurrence of several layers containing reworked hiatus concretions in the studied outcrop is interpreted as the result of recurrent sea-level falls caused by multiple glacial pulses characterising the overall cool climate in the late Pliensbachian. [ABSTRACT FROM AUTHOR]

Aim: The drivers of genetic diversity in Amazonia, the most species‐rich set of ecosystems on Earth, are still incompletely understood. Species from distinct Amazonian ecosystems have unique biogeographic histories that will reflect regional landscape and climatic drivers of genetic diversity. We studied bird species from patchy Amazonian white‐sand ecosystems (WSE) to evaluate the occurrence of shared biogeographic patterns to better understand the complex environmental and landscape history of Amazonia and its biodiversity. Location: Northern South America; Amazonia. Taxon: Passeriformes. Methods: We sequenced Ultra‐conserved Elements (UCEs) from 177 samples of seven bird species associated with WSE that have overlapping ranges. We used the SNP matrices and sequence data to estimate genetic structure and migration surfaces using 'conStruct' and eems, performed model‐selection to obtain the most probable demographic histories on 'PipeMaster' and implemented analyses of shared demography with ecoevolity. Results: Shallow genetic structure patterns varied among species. The Amazon river was the only barrier shared among them. Population structure dates to no more than 450,000 years ago. Nine geographically structured populations showed signals of population size changes and eight of these occur in Northern Amazonia. Population expansion was inferred at two distinct times: ~100,000 and ~ 50,000 years ago. The timing of co‐expanding populations is consistent with differences in habitat preference, as species that prefer dense scrubby to forested vegetation expanded more recently compared to species that prefer open vegetation. Main conclusions: WSE species responded in concert to environmental and landscape changes that occurred in the relatively recent past. Population expansions were likely driven by the genesis of new WSE patches and a return to wetter conditions after glacial periods. Pleistocene climatic cycles affected the distribution and dynamics of open vegetation habitats in Amazonia, especially in the Northern region, driving genetic diversity and demographic patterns of its associated biota. [ABSTRACT FROM AUTHOR]

Magnetic susceptibility (MS) of the Quaternary long‐term mid‐latitude Maros fluvial fan (Pannonian Basin) was recorded to understand the stratigraphical features of source‐proximal fluvial depositional settings. Three fully cored 500‐m‐deep boreholes were sampled at 0.5‐m intervals; low‐field and frequency dependent MS were measured, and complementary hysteresis and SEM‐EDAX investigations were performed on selected samples. Logged susceptibility data were also used to log correlations established by a simultaneous comparison of wireline log and laboratory measurements. Time‐series analyses of the susceptibility records reveal a ~41‐ka and ~100‐ka cyclicity. Towards the source‐distal sections the intensity of the ~41‐ka cycles decreases, while that of the ~100‐ka cycles remains strong. Stratigraphical and spectral similarities were observed between the Maros fluvial fan and Chinese loess records; however, based on complementary magnetic data, the magnetic phase of the Maros Fan sections is related to the detrital magnetite that originates from the catchment during early postglacial permafrost degradations. The amplification of the ~41‐ka cycles can be attributed to the very high susceptibility values in source‐proximal settings and to the special stratigraphical feature of the distributive fluvial systems. This comprises the increased avulsion frequency on the fluvial fans in 'glacial recession periods', in concert with the 'early postglacial' occurrence of the permafrost‐related magnetite originating from the catchment. As a local phenomenon, this is significant since it records the obliquity‐driven variations in permafrost development in a catchment. However, fluvial and alluvial fans are widespread depositional landforms within the Eurasian mountain range and were possibly the same during the Quaternary deglaciations. Thus, obliquity‐driven magnetic susceptibility variations in source‐proximal fan deposits attached or adjacent to regions of loess deposition should also be considered when scanning for potential source material of aeolian deposits. [ABSTRACT FROM AUTHOR]

Martian gullies are kilometer-scale, geologically young features with a source alcove, transportation channel, and depositional fan. On the walls of impact craters, these gullies typically incise into bedrock or surfaces modified by the latitude-dependent mantle (LDM; inferred as consisting of ice and admixed dust) and glaciation. To better understand the differences in the alcoves and fans of gullies formed in different substrates and infer the flow types that led to their formation, we have analyzed the morphology and morphometry of 167 gully systems in 29 craters distributed between 30 and 75 ∘ S. Specifically we measured length, width, gradient, area, relief, and relief ratio of the gully alcoves and fans; Melton ratio, relative concavity index, and perimeter; and form factor, elongation ratio, and circularity ratio of the gully alcoves. Our study reveals that gully alcoves formed in LDM/glacial deposits are more elongated than the gully alcoves formed in bedrock, and they possess a distinctive V-shaped cross section. We have found that the mean gradient of fans formed by gullies sourced in bedrock is steeper than the mean gradient of fans of gullies sourced in LDM/glacial deposits. These differences between gullies were found to be statistically significant and discriminant analysis has confirmed that alcove perimeter, alcove relief, and fan gradient are the most important variables for differentiating gullies according to their source substrates. The comparison between the Melton ratio, alcove length, and fan gradient of Martian and terrestrial gullies reveals that Martian gully systems were likely formed by terrestrial debris-flow-like processes. Present-day sublimation of CO2 ice on Mars may have provided the adequate flow fluidization for the formation of deposits akin to terrestrial debris-flow-like deposits. [ABSTRACT FROM AUTHOR]

The glaciogenic nature of the Yudnamutana Subgroup was first recognized over a century ago, and its global significance was recognized shortly after, with the eventual postulation of a global Sturtian Glaciation and Snowball Earth theory. Much debate on the origin and timing of these rocks, locally and globally, has ensued in the years since. A significant corpus of research on the lithology, sedimentology, geochronology and formal lithostratigraphy of these sequences globally has attempted to resolve many of these debates. In the type area for the Sturtian Glaciation, South Australia's Adelaide Superbasin, the lithostratigraphy and sedimentology are well understood; however, formal stratigraphic nomenclature has remained complicated and contested. Absolute dates on the stratigraphy are also extremely sparse in this area. The result of these longstanding issues has been disagreement as to whether the sedimentary rocks of the Yudnamutana Subgroup are truly correlative throughout South Australia, and if they were deposited in the same time span recently defined for Sturtian glacial rocks globally, c. 717 Ma to c. 660 Ma. This study presents a large detrital zircon study, summarizes and compiles existing global geochronology for the Sturtian Glaciation and revises the formal lithostratigraphic framework of the Yudnamutana Subgroup. We show equivalence of the rocks that comprise the revised Sturt Formation, the main glaciogenic unit of the Yudnamutana Subgroup, and that it was deposited within the time span globally defined for the Sturtian Glaciation. [ABSTRACT FROM AUTHOR]

Simple Summary: Previous paleoclimatic modelling studies on the European whip snake, Hierophis viridiflavus, hardly explain its genetic structure. Through the combination of phylogeographic and paleoclimatic modelling analyses, we reconstructed the biogeographic history of the species. Phylogeographic analyses recovered two major lineages that had diversified in different ways in the late Pleistocene. Paleoclimatic models unveiled the species range dynamics since the late Pleistocene, showing major range contractions into multiple climatic refugia in Southern Europe during glacial and interglacial events, as well as more recent northwards expansions. This study contributes to our knowledge of H. viridiflavus' historical biogeography and sheds more light on the evolutionary processes that took place in the Mediterranean Basin hotspot. Phylogeographic and paleoclimatic modelling studies have been combined to infer the role of Pleistocene climatic oscillations as drivers of the genetic structure and distribution of Mediterranean taxa. For the European whip snake, Hierophis viridiflavus, previous studies based on paleoclimatic modelling have depicted a low reliability in the pattern of past climatic suitability across the central Mediterranean Basin, which barely fits the species' genetic structure. In this study, we combined phylogeographic and paleoclimatic modelling tools to improve our understanding of the biogeographic history of H. viridiflavus, particularly extending the sampling and phylogeographic inferences to previously under-sampled regions. Phylogeographic analyses recovered two major clades that diverged at the beginning of the Pleistocene and had diversified in different ways by the late Pleistocene: the east clade (composed of three subclades) and the west clade (with no further structure). Paleoclimatic models highlighted the temperate character of H. viridiflavus, indicating range contractions during both the last inter-glacial and last glacial maximum periods. Range expansions from southern-located climatic refugia likely occurred in the Bølling–Allerød and Middle Holocene periods, which are supported by signals of demographic growth in the west clade and South–East–North subclade. Overall, this work improves our understanding of the historical biogeography of H. viridiflavus, providing further insights into the evolutionary processes that occurred in the Mediterranean Basin hotspot. [ABSTRACT FROM AUTHOR]

Uniformitarian scientists were surprised to discover channels on Mars like the Channeled Scablands of eastern Washington. Climate models indicate that large-scale Martian floods are impossible. This paper will describe what appear to be flood features on Mars. Three types of channels on Mars are described in this paper: valley networks, outflow channels, and gullies. Like the Solar System's other solid bodies that have not been resurfaced by debris and volcanism, Mars possesses numerous impact craters, some very large, which provide a framework for the planet's history. Secular uniformitarian scientists divide the geologic history of Mars into four main periods which span 4.5 billion years. [ABSTRACT FROM AUTHOR]

Throughout the Flinders Ranges of South Australia, the red bed Brachina sequence comprises the lower of two regressive, coarsening-upward successions that together constitute the Ediacaran-aged Wilpena Group. Detailed examination of the Brachina sequence has identified evidence of ice-rafting, supporting the contention that frigid climatic conditions continued well after cessation of the Marinoan Glaciation, as well as features postulated to be harbingers of the macroscopic metazoans that occur in abundance higher in the local stratigraphy. Although tuffaceous and lying stratigraphically between deposits of the Marinoan Glaciation and the Acraman Impact/Gaskiers Glaciation, no absolute age dates exist for the sequence. However, through correlation to the global carbon isotope profile, the timespan of Brachina sequence deposition can be constrained to between 635 and 586 Ma, when the regression climaxed with terrestrial deposition upon a local disconformity. The tuffaceous input is timed to have begun at 620 Ma, essentially coincident with initial formation of the passive volcanic continental margin of southeastern Australia and initiation of both the Volyn Large Igneous Province and activity within the Central Iapetus Magmatic Province, all components marking the demise of Rodinia and initial amalgamation of Gondwana. Correlation to the global carbon isotope profile dates the early Ediacaran Brachina sequence of the Flinders Ranges to between 635 and 586 Ma. The ABC Range Quartzite in the central Flinders Ranges is derived from, and hence younger than, the deltaic ABC Range Quartzite in the southwestern Flinders Ranges. Several volcanic outpourings across the Ediacaran globe during the final breakup of Rodinia and initial assembly of Gondwana, including that associated with the development of the eastern Australian passive margin, produced an abundance of atmospheric ash that settled during and beyond deposition of the Brachina sequence. [ABSTRACT FROM AUTHOR]

Siniperca undulata and S. obscura (Centrarchiformes: Sinipercidae) are small Chinese perches, living in creeks and streams in southern China. While they have sympatric distribution and occupy similar macrohabitat, their body sizes and ecological niches have many differences. Determining the genome sequences of S. undulata and S. obscura would provide us an essential data set for better understanding their genetic makeup and differences that may play important roles in their adaptation to different niches. We determined the genome sequences of both S. undulata and S. obscura using 10× genomics technology and the next-generation sequencing. The assembled genomes of S. undulata and S. obscura were 744 and 733 Mb, respectively. Gene family analysis revealed that there were no overlap between S. undulata and S. obscura in terms of rapid expanding and rapid contracting genes families, which were related to growth, immunity, and mobility. Positive selection analyses also cooperated that the function of selected genes involve growth, athletic ability, and immunity, which may explain the preference of different niches by S. undulata and S. obscura. Pairwise sequentially Markovian coalescent analyses for the two species suggested that populations of both S. undulata and S. obscura showed a rising trend between 90 and 70 Ka probably due to the mild environment during the last interglacial period. A stage of population shrinking occurred from 70 to 20 Ka, which was in with the Tali glacial period in eastern China (57-16 Ka). [ABSTRACT FROM AUTHOR]

Upper Palaeolithic archaeological sites in the Basque Country have been excavated for over a century. They have yielded a rich palaeoenvironmental record with zoological and botanical remains that have been obtained in stratigraphic series dated precisely by radiocarbon. This information reveals cyclical environmental changes from climates similar to today to drier and extremely cold conditions, when species in current boreal biomes and others now extinct but with similar ecological preferences were present in the region. Moreover, the archaeological sites have provided high-resolution information about the resilience mechanisms of the communities of our own human species. This information allows us to increase the corpus of palaeoclimate data regarding the Marine Isotopic Stage (MIS) 2 and MIS 3 for a critical region within the human population of Eurasia. The aim of this paper is to show how an extraordinary capacity for adaptation to drastic climate changes Upper Palaeolithic hunter–gatherer societies displayed, even though their subsistence depended on biotic resources that alter rapidly. [ABSTRACT FROM AUTHOR]

Pollen analysis was performed on 14 profiles of fossil biogenic sediments from different parts of the vast depression near the Wola Starogrodzka village (Central Poland). The results allowed the determination of the time of their accumulation for the period from the end of the Odra Glaciation (Warta Stage, Saalian, MIS-6), through the Eemian Interglacial (MIS-5e), to the first interstadial of the Early Vistulian (Brørup, MIS-5c). In many studied profiles, we noted the incompleteness in the pollen record of the Eemian vegetation succession - hiatuses occur usually in the hornbeam (E5) and/or spruce phase (E6). Moreover, the thickness of the same pollen zone and the development of its palynological record are strongly differentiated between individual profiles, e.g. the hornbeam zone (E5) is contained in an exceptionally thick sediment layer (3.7 m) in the PWS1-19 profile, and the oak zone (E3) in the WH-123 and PWS2-19 profiles (1.0 and 1.2 m, respectively), while in other profiles they are represented only by single pollen spectra. If we only had a single profile with a hiatus and/or a poorly developed pollen record, it would be impossible to reconstruct a complete interglacial succession of vegetation. However, having several such imperfect profiles which complemented each other enabled us to do it. [ABSTRACT FROM AUTHOR]

The article presents the stages of development of the alluvial fan of the Stryi River (tributary of the Dniester River), which is the largest alluvial cone in the foreland of the Eastern Carpathians. The alluvial fan has a diverse morphology and complex structure, and its formation is the result of the accumulation and erosion activity of several rivers. In order to reconstruct the evolution of the alluvial fan, geological cross-sections of the Stryi, Svicha and Dniester river valleys were made on the basis of archival drillings and field research. The stratigraphy of the alluvial fills is based mainly on morphological (morphostratigraphic) criteria and the correlation of terrace levels with those of adjacent areas. Fluvial sediments from the Late Glacial and Holocene were dated by the radiocarbon method, which allowed the determination of the age of fan dissection. The main factor controlling the course of accumulation and erosion on the alluvial fan was climate change. The accumulation of alluvial covers was preceded by phases of erosion, which generally fell at the end of the glacial periods (late glacial) and the beginning of the interglacials. Differences in the depth of dissection of the strath and the thickness of the accumulated alluvial sediments in the northern and southern parts of the fan may be the result of different tectonic movements and/or the transport capacity and size of river discharges. In the Late Glacial (Alleröd-Younger Dryas) and the Early Holocene the alluvial fan was dissected to a depth of 10-15 m due to the erosion of the Stryi and Dniester rivers. [ABSTRACT FROM AUTHOR]

This contribution characterises the stratigraphic schemes of the Quaternary as constructed and published by Leszek Lindner in 1967-2019. The oldest schemes assume the subdivision of the Pleistocene into three glaciations (i.e., Cracow, Middle-Polish and Baltic) separated by two interglacials (Great and Eemian). The scheme published in 1992 comprises eight glacial and seven interglacial units. The most recent scheme for the Quaternary contains seven advances of the Scandinavian ice-sheet on the area of Poland during the Nidanian (MIS 22), Sanian 1 (MIS 16), Sanian 2 (MIS 12), Liviecian (MIS 10), Krznanian (MIS 8), Odranian (MIS 6), and Vistulian (MIS 2-5d) glaciations. They are separated by six interglacials: Podlasian, Ferdynandovian, Mazovian, Zbójnian, Lublinian and Eemian. The ranges of glacial transgressions, and key interglacial and preglacial sites are assembled in a cumulative scheme for the area of Poland. We review the main study methods on which the subsequent versions of the stratigraphic scheme were based. These include Prof. Lindner's own detailed field research in glaciated and extraglacial areas, and paleofloristic, paleontological and paleomagnetic studies of major interglacial sites carried out by numerous researchers, as well as thorough literature studies. [ABSTRACT FROM AUTHOR]

On the southwest cape of the Congo craton, a subtropical carbonate bank the size of Greenland was heavily glaciated during two Cryogenian panglacial episodes spaced 10–20 Myr apart. In NW Namibia, the bank underwent crustal stretching with resultant Aegean Sea-type topography during the older and longer Sturtian glaciation (717–661 Ma). This is indicated by angular discordance between glacial and preglacial strata and diamictites sourced from all older units, including crystalline basement. In contrast, the bank was flat-topped and underwent broad thermal subsidence during Marinoan glaciation (646 ± 5–635 Ma), attested by stratal parallellism and diamictites sourced from ≤100 m stratigraphic depth. However, ≥2.0 km of relief existed on the Marinoan continental slope, where most glacial erosion and accumulation occurred. The average rates of Marinoan erosion (2.55–6.80 m/Myr, n = 190) and accumulation (2.65–7.07 m/Myr, n = 211) are indistinguishable, implying that the location in a continental promontory did not bias erosion over accumulation. The average accumulation rates for the Sturtian and Marinoan, scaled for different averaging times, including Marinoan uncertainty, are 3.95–4.93 m/Myr (n = 183) and 2.65–7.07 m/Myr (n = 190), respectively, suggesting that a Marinoan glacioeustatic coastal escarpment substituted for rift-related Sturtian basin-and-range topography. These slow rates, comparable to long-term pre-Quaternary accumulation rates on existing abyssal plains, reconcile glacial sedimentology with the feeble hydrologic cycle of snowball Earth. [ABSTRACT FROM AUTHOR]

Throughout the Plio-Pleistocene, climate change has impacted tropical marine ecosystems substantially, with even more severe impacts predicted in the Anthropocene. Although many studies have clarified demographic histories of seabirds in polar regions, the history of keystone seabirds of the tropics is unclear, despite the prominence of albatrosses (Diomedeidae, Procellariiformes) as the largest and most threatened group of oceanic seabirds. To understand the impact of climate change on tropical albatrosses, we investigated the evolutionary and demographic histories of all four North Pacific albatrosses and their prey using whole-genome analyses. We report a striking concordance in demographic histories among the four species, with a notable dip in effective population size at the beginning of the Pleistocene and a population expansion in the Last Glacial Period when sea levels were low, which resulted in increased potential coastal breeding sites. Abundance of the black-footed albatross dropped again during the Last Glacial Maximum, potentially linked to climate-driven loss of breeding sites and concordant genome-derived decreases in its major prey. We find very low genome-wide (π < 0.001) and adaptative genetic diversities across the albatrosses, with genes of the major histocompatibility complex close to monomorphic. We also identify recent selective sweeps at genes associated with hyperosmotic adaptation, longevity, and cognition and memory. Our study has shed light on the evolutionary and demographic histories of the largest tropical oceanic seabirds and provides evidence for their large population fluctuations and alarmingly low genetic diversities. [ABSTRACT FROM AUTHOR]

North‐central Poland was originally shaped by the Płock lobe of the ice sheet formed during the Weichselian Glaciation. The majority of the studied area comprises the Dobrzyń Lakeland, where numerous terminal moraine hills preserve a record of recession of the ice sheet from the maximum extent of the last glaciation (LGM). Analysis of a digital elevation model enabled the determination of a network of morpholineaments, referring to the formation of linear glacial forms. Recession of the ice sheet from the LGM extent in north‐central Poland was uneven and proceeded in stages. Ice‐sheet recession stages were interspersed with local or regional ice‐sheet advance stages. During these individual periods of ice‐sheet behaviour, ice‐sheet movement changed direction from WNW–ESE to NNW–SSE. Transgression of the ice sheet into the central part of the study area as well as the Kujawy–Dobrzyń subphase may be related to cooling of the climate during 18.5–17.7 ka before ad 2000. [ABSTRACT FROM AUTHOR]

Forty years ago, lichens were identified as extraordinary biological ice nucleators (INs) that enable ice formation at temperatures close to 0 ∘ C. By employing INs, lichens thrive in freezing environments that surpass the physiological limits of other vegetation, thus making them the majority of vegetative biomass in northern ecosystems. Aerosolized lichen INs might further impact cloud glaciation and have the potential to alter atmospheric processes in a warming Arctic. Despite the ecological importance and formidable ice nucleation activities, the abundance, diversity, sources, and role of ice nucleation in lichens remain poorly understood. Here, we investigate the ice nucleation capabilities of lichens collected from various ecosystems across Alaska. We find ice nucleating activity in lichen to be widespread, particularly in the coastal rainforest of southeast Alaska. Across 29 investigated lichen, all species show ice nucleation temperatures above -15 ∘ C, and ∼30 % initiate freezing at temperatures above -6 ∘ C. Concentration series of lichen ice nucleation assays in combination with statistical analysis reveal that the lichens contain two subpopulations of INs, similar to previous observations in bacteria. However, unlike the bacterial INs, the lichen INs appear as independent subpopulations resistant to freeze–thaw cycles and against temperature treatment. The ubiquity and high stability of the lichen INs suggest that they can impact local atmospheric processes and that ice nucleation activity is an essential trait for their survival in cold environments. [ABSTRACT FROM AUTHOR]

The marine dissolved organic carbon (DOC) reservoir rivals the atmospheric carbon inventory in size. Recent work has suggested that the size of the DOC reservoir may respond to variations in sea temperature and global overturning circulation strength. Moreover, mobilization of marine DOC has been implicated in paleoclimate events including Cryogenian glaciation and Eocene hyperthermals. Despite these suggestions, the dynamics of the marine DOC reservoir are poorly understood, and previous carbon cycle modeling has generally assumed this reservoir to be static. In this study, we utilize an Earth system model of intermediate complexity to assess the response of the marine DOC reservoir to various glacial boundary conditions. Our results indicate that the marine DOC reservoir is responsive to glacial perturbations and may shrink or expand on the order of 10–100 Pg C. In contrast to recent studies that emphasize the importance of DOC degradation in driving the mobility of DOC reservoir, our study indicates the importance of DOC production. In the experiment under full glacial boundary conditions, for example, a 19% drop in net primary production leads to an 81 Pg C reduction in the DOC pool, without which the atmospheric CO2 concentration would have been lower by approximately 38 ppm by dissolved inorganic carbon changes alone. Thus, DOC reservoir variability is necessary to fully account for the simulated changes in atmospheric CO2 concentration. Our findings based on glacial experiments are corroborated in a different set of simulations using freshwater flux to induce weakening of the Atlantic meridional overturning circulation. Plain Language Summary: There is a significant reservoir of dissolved organic carbon (DOC) in the ocean originating from the production and decay of microbes, nearly equal to the amount of carbon contained as carbon dioxide (CO2) in the atmosphere. Studies have suggested that the total amount of DOC in the ocean may respond to climate effects on ocean temperatures and circulation, and that releases of DOC from the ocean as CO2 to the atmosphere may have contributed to some climate change events in Earth's history. To date, however, little modeling work has been done to understand this suggestion. In this study, we used a computer model of the earth's ocean and atmosphere to simulate the response of marine DOC to climate conditions representing the height of Earth's last glacial period. We found that the total amount of marine DOC simulated in our model could vary in response to the specific climate conditions applied and the modeled impacts on ocean biological production. Importantly, we found that these changes in the DOC reservoir are sufficiently large that without it, changes in atmospheric CO2 levels cannot be fully understood. Our results suggest that understanding marine DOC is crucial in understanding global climate changes throughout Earth's history. Key Points: The marine dissolved organic carbon (DOC) reservoir is mobile in response to glacial climate forcing and rapid changes in the meridional overturning circulationChanges in the size of the DOC reservoir are primarily driven by changes in DOC production rather than DOC degradationMarine DOC cycling is directly related to atmospheric pCO2 over simulated climate change events [ABSTRACT FROM AUTHOR]

The research was carried out as part of the preparation “Water Resources” section of the 4th National Communication of the Kyrgyz Republic to the UNFCCC. The article presents extensive information on the current state and changes over a long period of observations of water resources, climate and glaciation in Kyrgyzstan (Syr-Darya and Amu-Darya river basins). The representative rivers were selected as the main objects, which are transboundary between Kyrgyzstan, Uzbekistan, Kazakhstan and Tajikistan. The study aims to assess the inter-annual and intra-annual dynamics of the flow of the rivers for the period from 2020 to 2080, based on the climate projections CMIP5 (RCP4.5 and RCP8.5) and CMIP6 (SSP2-4.5 and SSP5-8.5) (IPCC WG II Report, 2022). The hydrological modeling method in the HBV light and HBV EHT models and the inertial mean annual flow change method were used to estimate changes in water resources. On the rivers of the northern part of the Fergana Valley, the average annual runoff is expected to increase by 1-19%, in the Amudarya river basin (Kyzyl-Suu river) – by 27-64% of the values for 2006-2019. In the Naryn river, water discharge for this period will remain within the current values for 2006-2019. The method of inertial change in the average annual runoff showed an increase in runoff for 2030 and 2040 for all the studied catchment areas by 6-19% of the current values for 2006-2020. The results of the study are intended for decision-makers on the rational use and long-term planning of water resources under climate change.

Wrinkle ridges are common landforms documented on all rocky planets and the Moon in the inner solar system. Despite the long research history, their formation mechanisms remain debated. A key unresolved issue is whether the wrinkle-ridge formation is related to igneous processes. This is because wrinkle ridges are mostly associated in space and possibly in time with the occurrence of flood-basalt volcanism in all cases in the inner solar system. To address this issue, we conducted geomorphological mapping, a topographic-data analysis, and a detailed landform and landsystem analysis of satellite images at a resolution of 25 cm/pixel to 6 m/pixel in the central Tharsis region of Mars. The main results of this work are in the form of (1) a regional geomorphological map at a resolution of 6 m/pixel and (2) a local geomorphological map at a resolution of 50 cm/pixel. Our work suggests the following older-to-younger sequence of geological events in the study area: (1) formation of a northeast-trending mountain range (i.e., the Thaumasia plateau) along the eastern margin of the Tharsis rise that was created by the Himalayan-style crustal-scale thrusting; (2) coeval volcanic-plateau construction west of the thrusting-induced rising mountain range; (3) eastward-flowing lavas that were sourced from a volcanic plateau to the west terminated at the rising Thaumasia plateau to the east; (4) wrinkle-ridge development by decollement folding of recently emplaced warm, ductile volcanic-lava piles; (5) emplacement of a regionally extensive ice sheet over the central Tharsis region that produced extensive boulder-bearing materials, striated surfaces, and boulder-bearing dendritic-ridge networks possibly representing subglacial eskers; and (6) local deposition of highly concentrated glacial flours resulted in the formation of mantled terrain on plains between wrinkle ridges. Our work supports the early suggestion that the Tharsis wrinkle ridges were created by horizontal shortening induced by crustal-scale tectonic processes. In detail, however, the occurrence of flow-front-like fold margins associated with many mapped wrinkle ridges suggests the involvement of ductile-flow deformation during ridge formation. We attribute the flow-like fold fronts to ductile deformation of thermally weakened lava piles that were emplaced during or immediately before the folding event. Our compression-induced wrinkle-ridge model also differs from the early hypotheses in that the thin-skinned folding is associated with basement subduction, which explains the lack of coeval and parallel folding and extensional faulting associated with wrinkle ridge formation in the study area. Post-folding glacial modification means that the present wrinkle-ridge morphologies may differ significantly from the original fold shapes, which prevents the utility of using topographic profiles across wrinkle ridges for inverting the underlying thrust geometries.

In the Ennedi Plateau, northeastern Chad, Cambrian(?)–Ordovician to Carboniferous strata represent one of the most proximal succession of the north-facing Gondwana platform. This study presents preliminary results related to the c. 200 m-thick Lower Sandstones and overlying Bedo Formation, which essentially record Early to Middle Ordovician flooding events and the end-Ordovician glaciation and subsequent deglaciation. In the Lower Sandstones, fluvial-dominated deposits (prevailing cross-stratification, NW to NNE paleocurrent trends) include intervening high-frequency marine incursions (tidal deposits, ichnofacies including Cruziana and Arthrophycus). Above an erosional unconformity, the end-Ordovician glacial record consists of fluvioglacial conglomeratic deposits atop the Lower Sandstones, which are in turn superimposed by the fine-grained Bedo Formation. The latter interval, onlapping an exhumed erosion surface showing north-trending km-scale glacial lineations, shows glaciomarine deposits only at its base and possibly include Lower Silurian deposits in its upper part.

Comprehensive geological, geophysical, geomorphological, and hydrophysical studies were carried out on the R/V Akademik Boris Petrov in the eastern Barents Sea and western Kara Sea in fall 2022. The research included multibeam echo sounding and seismic profiling, hydrological sounding, and sampling of water and sediments in the areas of oil and gas field development and along the Northern Sea Route. The expedition studied in depth the structure of the seabed relief and upper sedimentary strata at the given research sites. The distribution areas of various glacial landforms and modern geohazards were refined during the expedition. [ABSTRACT FROM AUTHOR]

Siraitia grosvenorii, an economically important plant species with high medicinal value, is endemic to subtropical China. To determine the population structure and origin of cultivated S. grosvenorii, we examined the variation in three chloroplast DNA regions (trnR‐atpA, trnH‐psbA, trnL‐trnF) and two orthologous nuclear genes (CHS and EDL2) of S. grosvenorii in 130 wild individuals (selected from 13 wild populations across its natural distribution range) and 21 cultivated individuals using a phylogeographic approach. The results showed three distinct chloroplast lineages, which were restricted to different mountain ranges, and strong plastid phylogeographic structure. Our findings suggest that S. grosvenorii likely experienced ancient range expansion and survived in multiple refuges in subtropical China during glacial periods, resulting in population fragmentation in different mountainous areas. Our results also demonstrated that wild populations in Guilin (Guangxi, China) share the same gene pool as cultivated S. grosvenorii, suggesting that current cultivars were collected directly from local wild resources, consistent with the principles of "nearby domestication." The results of this study provide insights into improving the efficiency of S. grosvenorii breeding using a genetic approach and outline measures for the conservation of its genetic resources. [ABSTRACT FROM AUTHOR]

The Hengduan Mountains region is a biodiversity hotspot known for its topologically complex, deep valleys and high mountains. While landscape and glacial refugia have been evoked to explain patterns of interspecies divergence, the accumulation of intra‐species (i.e., population level) genetic divergence across the mountain‐valley landscape in this region has received less attention. We used genome‐wide restriction site‐associated DNA sequencing (RADseq) to reveal signatures of Pleistocene glaciation in populations of Thitarodes shambalaensis (Lepidoptera: Hepialidae), the host moth of parasitic Ophiocordyceps sinensis (Hypocreales: Ophiocordycipitaceae) or "caterpillar fungus" endemic to the glacier of eastern Mt. Gongga. We used moraine history along the glacier valleys to model the distribution and environmental barriers to gene flow across populations of T. shambalaensis. We found that moth populations separated by less than 10 km exhibited valley‐based population genetic clustering and isolation‐by‐distance (IBD), while gene flow among populations was best explained by models using information about their distributions at the local last glacial maximum (LGML, 58 kya), not their contemporary distribution. Maximum likelihood lineage history among populations, and among subpopulations as little as 500 m apart, recapitulated glaciation history across the landscape. We also found signals of isolated population expansion following the retreat of LGML glaciers. These results reveal the fine‐scale, long‐term historical influence of landscape and glaciation on the genetic structuring of populations of an endangered and economically important insect species. Similar mechanisms, given enough time and continued isolation, could explain the contribution of glacier refugia to the generation of species diversity among the Hengduan Mountains. [ABSTRACT FROM AUTHOR]