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The north and south polar layered deposits (PLD) on Mars are composed of stacks of layered ice and dust, but the SPLD is approximately twice as bright as the NPLD in 20‐MHz radar echoes. We use Shallow Radar (SHARAD) data in ∼4‐MHz bands centered on 17.5 MHz ("L") and 22.5 MHz ("H") to determine whether radar reflectivity variations are due to scattering effects related to closely spaced, near‐surface dielectric layering. We mapped the ratio of the surface echo power at the two frequencies (H/L) for both PLDs. The NPLD has large areas where H and L echo power differ, consistent with destructive interference in the H band within the uppermost ∼20 m. The SPLD is dominated by H ∼ L (unity), except for isolated regions in and near the residual CO2 cap and Australe Lingula. The H/L variations can be partly explained by near‐surface structure, where large variations in H/L match locations with numerous near‐surface reflecting interfaces, and locations where H ∼L may contain few such reflectors. There is no obvious connection between H/L and surface morphology, but the distribution of non‐unity H/L resembles the extent of a widespread, recent accumulated package (WRAP) at both poles. The spatial association between H/L and WRAP and interference indicated by H/L suggests that large regions in the NPLD—and isolated areas in the SPLD—are characterized by shallow layer(s) of consistent thickness/separation potentially deposited within the past few tens of kyr as Mars emerged from the last obliquity‐driven ice age. Plain Language Summary: The north and south poles of Mars reflect radar energy differently, where the south polar region is more reflective than the north. We used radar data from the Shallow Radar instrument to investigate how the near‐surface ice and dust layering could affect reflectivity. We found that the north polar region is more densely layered near the surface, leading to radar signal interference that changes the reflectivity. The south polar region, in contrast, has fewer near‐surface reflectors in many locations. Both poles show evidence of interference in similar locations as a widespread young deposit of ice and dust layers that formed in the past ∼300,000 years. Since our data (which describe to the top several meters of the surface) suggest interference occurs in regions similar to this young deposit, one explanation is that these regions of strong radar interference accumulated over the past ∼20,000 years. Key Points: North and south polar layered deposits have different radar surface reflectivities due in part to layering in the uppermost ∼20 mInterference effects in radar scattering occur more often in the densely layered north polar depositsDifferences in reflectivity and near‐surface structure could indicate the extent of recent ice/dust accumulation in the past ∼20 kyr [ABSTRACT FROM AUTHOR]

The Late Paleozoic ice age is a vital event in the geological history. The sea level change caused by the Late Paleozoic ice age has a far-reaching impact on the reef system. The response of reefs to sea-level change in the context of the Late Paleozoic ice age is discussed. Reefs exhibit three primary modes of response：“abandonment”, “synchronization”, “persistence”. We calculated the rise of sea level in Gzhelian by the large Bianping coral reef in southern Guizhou. The sea level of Gzhelian in southern Guizhou rose by about （60±5）m, which is mainly caused by glaciation. The sources of error in this estimation chiefly revolve around basement subsidence and inaccurate estimation of paleo-water depth. The morphology and rapid growth characteristics of Fomitchevella reveal the paleoenvironmental conditions of warm climate, rising sea level and rapid transgression in the Gzhelian period in southern Guizhou. The development of the Bianping coral reef reflects the global climate change and sea level fluctuations are related to the ice age. [ABSTRACT FROM AUTHOR]

All else equal, if the ocean's "biological [carbon] pump" strengthens, the dissolved oxygen (O2) content of the ocean interior declines. Confidence is now high that the ocean interior as a whole contained less oxygen during the ice ages. This is strong evidence that the ocean's biological pump stored more carbon in the ocean interior during the ice ages, providing the core of an explanation for the lower atmospheric carbon dioxide (CO2) concentrations of the ice ages. Vollmer et al. (2022, https://doi.org/10.1029/2021PA004339) combine proxies for the oxygen and nutrient content of bottom waters to show that the ocean nutrient reservoir was more completely harnessed by the biological pump during the Last Glacial Maximum, with an increase in the proportion of dissolved nutrients in the ocean interior that were "regenerated" (transported as sinking organic matter from the ocean surface to the interior) rather than "preformed" (transported to the interior as dissolved nutrients by ocean circulation). This points to changes in the Southern Ocean, the dominant source of preformed nutrients in the modern ocean, with an apparent additional contribution from a decline in the preformed nutrient content of North Atlantic‐formed interior water. Vollmer et al. also find a lack of LGM‐to‐Holocene difference in the preformed 13C/12C ratio of dissolved inorganic carbon. This finding may allow future studies to resolve which of the proposed Southern Ocean mechanisms was most responsible for enhanced ocean CO2 storage during the ice ages: (a) coupled changes in ocean circulation and biological productivity, or (b) physical limitations on air‐sea gas exchange. Plain Language Summary: Recent studies have sealed the case that the concentration of oxygen was reduced in the deep ocean during the ice ages. Vollmer et al. (2022, https://doi.org/10.1029/2021PA004339) combine the oxygen results with data on deep ocean nutrient concentrations. They find that, relative to modern, more of the ice age deep ocean's nutrient reservoir arrived as sinking organic matter from surface waters, leading to more storage of carbon dioxide in the deep ocean. Moreover, they calculate that the entire observed drawdown in atmospheric carbon dioxide levels during ice ages can be explained by this strengthening of the ocean's "biological carbon pump." The findings bring the scientific community an important step closer to explaining why and how ice ages occur and end. The Southern Ocean, the ocean region around Antarctica, must have played a major role. However, it remains unclear whether the carbon dioxide was trapped in the Southern Ocean by changes in its circulation and biology or by limitations on air‐sea gas exchange across the Southern Ocean surface, such as might have occurred due to sea ice cover. Vollmer et al.'s reconstruction of the carbon isotopes in Southern Ocean surface waters may help to answer this question. Key Points: Proxies indicate less dissolved O2 in the ocean interior during ice ages than during interglacialsThis suggests an increase in CO2 storage by the ocean's biological pump adequate to explain the lower atmospheric CO2 of the ice agesReconstructed nutrient use implicates the Southern Ocean but does not yet resolve the roles of circulation, biology, and gas exchange [ABSTRACT FROM AUTHOR]

A discussion is presented of the effects generated by the imbalance between the insolation energy of polar-day zones and the radiation energy of polar-night zones on multicentennial changes in the Earth's climate. The dependence of this imbalance on the Earth's orbital parameters is determined. The energy imbalance curves are compared with the known temperature curves for the polar regions, which have been estimated from the results of an analysis of ice cores taken in Antarctica and Greenland. The curves clearly reveal a difference between the contributions of cosmic and terrestrial factors to the temperature profiles for the regions in question and demonstrate a synchronicity of these factors. Algorithms are obtained for calculating the magnitude of fluctuations in the size of the Earth's polar caps relative to their averages. The results obtained within the assumptions taken in this work enable predictions to be made about the development of the current global warming and about changes in the size of the Arctic and Antarctic polar caps. It is predicted that over the next three millennia, changes in the Earth's orbital parameters will contribute to the slow melting of the northern polar cap. Then, the trend for a new growth of the northern polar cap will again manifest itself. In the Southern Hemisphere, a trend towards increased glaciation has already formed. Influenced by the cosmic factor, it will intensify over the next 20 000 years. [ABSTRACT FROM AUTHOR]

The article is devoted to the problem of climate change on Earth, and in particular in the Caucasus. The main trends in climate change are traced during the Holocene epoch of the Quaternary period. Attention is focused on the most noticeable periods of cooling and warming - the medieval warming period, the Little Ice Age, the newest warming period, which began at the end of the 19th century. The issue of global warming is also touched upon. [ABSTRACT FROM AUTHOR]

For a long time after the end of large-scale student unrest in the 1970s Japan stood out by a comparatively low level of protest. Yet spectacular waves of mass-protest returned with the anti-nuke mobilizations following the 2011 Fukushima meltdown and other 'post-2011' movements. In this paper I develop an analytical framework inspired by the multi-level perspective in transition studies to illuminate two questions: how can the relatively low level of protest in Japan before 2011 – in particular the so called 'ice age' of protest from the 1970s to the early 2000s – be explained, and what enabled the recovery of protest afterwards, starting in the early 2000s and leading up to the post-2011 protest cycle? I point to the crucial role played on the one hand by niches in the form of social movement spaces in fostering oppositional discourses and on the other hand by landscape changes that destabilized the established politico-cultural regime. A crucial role was played by the creative work of freeter activists in social movement spaces during the 1990s who reinvented activism in response to stigmatization of open protest after the collective trauma of the perceived defeat of the New Left in the 1970s. This creative work was a precondition for the rise of protest movements in the early 2000s which in turn prepared the way for the post-2011 protest wave. [ABSTRACT FROM AUTHOR]

This multidisciplinary research paper examines Genesis, Chapter 8:13-22 which is the immediate post-Flood phase of the global Genesis Deluge. In a companion paper, I previously performed an exegetical and geological analysis of Genesis, Chapter 8:1-12 which documented the receding phase of the global Flood which was responsible for depositing the Tejas Megasequence (Paleogene and Neogene of the geological column). The receding phase of the Flood described in Genesis 8:1-12 encompassed 135 days of highly significant Earthshaping activity and is responsible for producing approximately a third of the total volume of the fossil-bearing portion of the geological column (Phanerozoic). The Tejas deposits are also responsible for the burying of numerous amounts of mammals, angiosperms, and many other plants and creatures living at higher pre-Flood elevations that are not found in lower (pre-Tejas) layers of the rock record. In this present analysis of Genesis 8:13-22, I exegete the Hebrew text showing that the earth surrounding the Ark landing site in the Middle East was completely dry by Genesis 8:14, and likely all the continents, which allowed for the disembarking of Noah, his family, and the animals off the Ark as noted in the following verses. Significantly, the Middle East is dominated by Tejas deposits of marine origin which were deposited in the receding phase of the Flood and according to the completed action of the verbal forms in the Hebrew text, was decidedly dry enough at the time of disembarkment and also for subsequent human development of the land of Shinar and the building of the tower of Babel. [ABSTRACT FROM AUTHOR]

We developed a new time-calibrated tree incorporating primarily endemic along with some cryptic Ryukyu islands cicada data, following the recent publication of global cicada data by Marshall et al. (2018), Łukasik et al. (2018), Simon et al. (2019), Price et al. (2019), and Hill et al. (2021). A total of 352 specimens were analyzed using BEAST v1. X software with a relaxed clock model. Fossil calibrations as old as Triassic were adopted largely following Johnson et al. (2018) and Moulds (2018), and a Quaternary geological event calibration was adopted following Osozawa et al. (2012, 2021b) and input into BEAST v1. X. Our timetree suggests that Tettigarctidae had a cicada basal lineage as old as 200.63 Ma, with Derotettiginae the next oldest lineage at 99.2 Ma. Tibicininae is a sister of the remaining subfamilies of Tettigomyiinae, Cicadettinae, and Cicadidae, and their species level differentiation and radiation began at 40.57 Ma. The Cicadinae clade consists of specific tribes with parapheletic relationship, and the vicariance and adaptive radiation generated many cryptic species in each tribe. We estimated base substitution rate as a function of age, and the result strongly indicates an exponential increase of base substitution rate in recent geologic time. The consequent increase in cicada biodiversity, including generation of cryptic species in the Ryukyu Islands and surroundings, may have been driven by the generation and spreading of C4 grasses and coeval Quaternary climate change.

Paleo-proxy reconstructions reveal a moistening of the American Southwest during the Last Glacial Maximum (LGM; 21 ka). However, the primary mechanisms driving the moistening trend are still debated, with relatively few studies focused on hypotheses related to synoptic changes in precipitation. Analysis of the Paleoclimate Intercomparison Model Project (PMIP3) simulations shows enhancement of precipitation in the southwest and south-central United States during the winter and summer. Here, we suggest that summertime eastward phase shifting of stationary waves at the LGMenhanced precipitation in the south-central United States and dried the southeastern United States. Mechanism denial experiments performed with version 3 of the Hadley Centre Coupled Model (HadCM3) indicate that the thermodynamic effect of the Laurentide Ice Sheet forced eastward phase shifting of stationary waves. By comparing a synthesis of LGM proxies to the PMIP3 ensemble, we find models that compare more favorably to the reconstructions simulate a weaker Laurentide ice thermodynamic effect, smaller eastward phase shifting of stationary waves, and weaker jet stream anomalies. [ABSTRACT FROM AUTHOR]

In 1976 M.W. Mahaffy published a basic ice-sheet model which did not make the usual steady-state assumption of constant height and which allowed for time-varying ice accumulation rates. For this reason his model should be of interest to creation researchers, who can use it to model the rapid growth of post-Flood ice sheets. This paper provides a brief overview of the theory and assumptions behind Mahaffy's model and its solution. The model is used to simulate the rapid growth of a long but thin isothermal ice ridge. The results are then compared with the results from the Vardiman model. A suggested technique for using the Dansgaard-Johnsen and Mahaffy ice sheet models to estimate annual layer thicknesses near an ice divide is also presented. [ABSTRACT FROM AUTHOR]

The fossil piece of an "Aves" once recorded but then long neglected, from the 18000 yrBP "Felis bed" of the Gansuiji Formation of the Nekata Site of Gansuiji, Hamakita, Hamamatsu City, Shizuoka Prefecture, central Japan(NSMS-PV 25157) was identified as the Cinereous Vulture Aegypius monachus here. The specimen is a well-fossilized distal portion of the right tarsometatarsus. The "Felis bed" was named after the characteristic fossil occurrence of tiger. This bed also yielded the older individual of "Hamakita Man" Homo sapiens fossils. This paper confirms the co-existence of an early population of Homo sapiens in Japan with tiger and vulture in the Hamakita area during the last ice age. This is the first fossil record of Cinereous Vulture in Japan, and the most easterly fossil occurrence of this species. The climate of the Japanese Archipelago during the last glacial maximum was similar to the original habitat of the Cinereous Vulture. It is possible that this species lived in the Japanese Archipelago as the resident bird during the last ice age. [ABSTRACT FROM AUTHOR]

O'Dea et al. (2022) (Pleistocene sea level changes and crocodile population histories on the isthmus of panama: a comment on Avila-Cervantes et al. (2020). Evolution , 76(11), 2778–2783. https://doi.org/10.1111/evo.14610) question our hypothesis that sea-level changes during the past glaciation played a role in restricting gene flow between Pacific and Caribbean Crocodylus acutus in Panama. They argue that an error in sea-level high-stand reconstruction during the last interglacial period (118–130 ka) does not support our hypothesis. Although they are correct in our high-stand reconstruction error, overlooked the point in that we were presenting a model of restricted gene flow across the Panamanian Isthmus during low sea levels. We review the assumptions of gene demographic methods, emphasizing that we were focusing on times of genetic divergence. We expand here why gene flow between these coastal populations could have been restricted during the last glacial maximum (19–26.5 ka) and the 50,000 years preceding it when sea levels were lower than today. O'Dea et al. suggest local climates may have played larger roles than sea levels. We demonstrate that paleoclimate estimates for the past 3.3 Ma in Panama are within the bounds of extant C. acutus. The importance of Ice Age Sea-level dynamics on Neotropical species was likely profound and should be incorporated into evolutionary studies of these taxa. [ABSTRACT FROM AUTHOR]

Paleontological studies of the distant past and historical chronicles of the last millennia indicate that warming and cooling of the climate on our planet, replacing each other, have taken place in a continuous series. An important role in this process has been and is played by cosmic factors: variations in solar activity and parameters of the Earth's orbital motion in the gravitational field of the Sun and the planets of the Solar System. It is suggested that the currently observed climate change is associated with a decrease in the eccentricity of the Earth's orbit and the inclination of the axis of its rotation relative to the plane of the ecliptic, which has been going on for almost 30 thousand years. Both processes lead to changes in the boundaries of climatic zones. In the foreseeable future, these processes will proceed in the same direction. Therefore, the current trend towards climate change will continue. Despite the importance of addressing the problem of reducing greenhouse-gas emissions as soon as possible, this paper expresses doubts about the possibility of fending off climate warming in this way. It is proposed to focus on the development of mathematical climate models taking into account space factors and on finding the best ways to adapt industry, transport systems, and the environment to the conditions of expected climate change. [ABSTRACT FROM AUTHOR]

Estimates of ice volume over the last 120 ka, from marine isotope Stage (MIS) 5d (∼110 ka) through MIS 3 (60–26 ka) are uncertain. Weiss et al. (2022, https://doi.org/10.1029/2021PA004361) offer an innovative new constraint on past sea level using the oxygen isotopes (δ18O) of planktic (surface and thermocline dwelling) foraminifers to infer the salinity of the Sulu Sea in the Indo‐Pacific Ocean and assess flow through the Karimata Strait (Indonesia) over the last glaciation. Based on the timing of Karimata Strait flooding, the study concludes that local relative sea level in the Karimata Strait was >−8 ± $\pm $ 6 m during MIS 5c (∼100 ka) and >−12 ± $\pm $ 6 m during MIS 5a (∼80 ka), relative to present. For MIS 3, a maximum possible relative sea level of −16 ± $\pm $ 6 m is determined. Here, these results are placed into the context of current knowledge of last glacial sea‐level change and the implications for climate forcings and feedbacks (e.g., global average surface temperature and greenhouse gases) and ice sheet growth are discussed. By tracing past ocean circulation patterns that are modulated by the depth of shallow straits such as the Karimata Strait, Weiss et al. (2022, https://doi.org/10.1029/2021PA004361) provide independent constraints on local sea level, which are essential for improving global mean sea level reconstructions on late Pleistocene glacial‐interglacial cycles. Key Points: Weiss et al. use planktic oxygen isotopes (δ18O) infer flooding and exposure of the Karimata Strait (Indonesia) over the last glacial cycleNew sea‐level constraints are contextualized within ongoing debates about global ice volumes during the last glaciation phasePast ocean circulation offers new insight into glacial‐interglacial sea‐level change [ABSTRACT FROM AUTHOR]

The C‐repeat binding factors/dehydration‐responsive element binding protein 1s (CBFs/DREB1s) have been identified as major regulators of cold acclimation in many angiosperm plants. However, their origin and evolutionary process associated to cold responsiveness are still lacking. By integrating multi‐omics data of genomes, transcriptomes, and CBFs/DREB1s genome‐wide binding profiles, we unveil the origin and evolution of CBFs/DREB1s and their regulatory network. Gene collinearity and phylogeny analyses show that CBF/DREB1 is an innovation evolved from tandem duplication‐derived DREB III gene. A subsequent event of ε‐whole genome duplication led to two CBF/DREB1 archetypes (Clades I and II) in ancient angiosperms. In contrast to cold‐insensitivity of Clade I and their parent DREB III genes, Clade II evolved a further innovation in cold‐sensitive response and was stepwise expanded in eudicots and monocots by independent duplications. In geological time, the duplication events were mainly enriched around the Cretaceous–Paleogene (K–Pg) boundary and/or in the Late Cenozoic Ice Age, when the global average temperature significantly decreased. Consequently, the duplicated CBF/DREB1 genes contributed to the rewiring of CBFs/DREB1s‐regulatory network for cold tolerance. Altogether, our results highlight an origin and convergent evolution of CBFs/DREB1s and their regulatory network probably for angiosperms adaptation to global cooling. [ABSTRACT FROM AUTHOR]

Using all relevant climate experiments archived in phases 3 and 4 of the Paleoclimate Modeling Intercomparison Project (PMIP3/4), we examine the interannual variability change in global-scale surface air temperature and associated physical mechanisms during the Last Glacial Maximum (LGM). The results show that relative to the preindustrial period, the LGM interannual temperature variability increased by 20% globally, which was mainly attributed to the large-scale increase in the meridional temperature gradient, especially at midlatitudes. Larger magnitudes of change occurred in areas where the underlying surface properties, such as the surface altitude, land–sea distribution, and ice sheet extent, differed from those in the preindustrial period. In addition, the relationship between changes in the meridional temperature gradient and the interannual temperature variability became closer in the winter hemisphere. In the tropical land regions, changes in interannual temperature variability are mainly related to the adjustment of latent and sensible heat fluxes during the LGM. [ABSTRACT FROM AUTHOR]

Through an in-depth study of the literature, as well as some other sources of information, geographical distribution maps of the various taxa of the European freshwater planarian genus Crenobia (Platyhelminthes, Tricladida) are provided, which document their records and distributional ranges in a detail that was previously unavailable. The genus Crenobia ranges across Northern, Western, Southern, and Eastern Europe, including several islands in the Mediterranean region, but is absent from a major part of the Iberian Peninsula; it is distributed also in Turkey. The chromosome portrait of Crenobia is complex, as it exhibits chromosome numbers that are multiples of 7, such as 28, 35, 42, 56, and 63. Sexually reproducing populations are tetraploid or hexaploid, while asexually reproducing populations exhibit high chromosome numbers. All taxa of Crenobia are stenothermic, cold-loving species. Although historical biogeographic scenarios interpreting the taxonomic diversification of the genus as being the result of the vicissitudes of the Last Ice Age are still captivating, it may be the case that the genus already diversified 6-20 million years ago. The paper sketches in some detail the anatomy of the copulatory complex of the various taxa. Previously, it went unnoticed that in two of the taxa (Crenobia alpina and C. anophthalma) the two sperm ducts have different, asymmetrical trajectories. Further, it was largely undocumented that in several taxa the sperm ducts exhibit a pronounced recurvature, as well as a dorsal loop before entering the penis papilla. Neither did previous studies document that in C. montenigrina the mouth opening is not located at the most posterior end of the pharyngeal pocket, but has shifted anteriad for some distance. Polypharyngy is a stable, species-specific character, with C. montenigrina usually exhibiting 11-17 pharynges, while C. anophthalma has never more than three pharynges. Different views have been expressed on the taxonomic status of several geographic and anatomical forms of Crenobia. It is shown here that Crenobia comprises five, well-defined full species, viz., C. alpina , C. corsica , C. montenigrina , C. anophthalma , and C. bathycola. [ABSTRACT FROM AUTHOR]

We sought to identify counties in the northeastern United States where the incidence of infant botulism (IB) is elevated compared to the nationwide incidence and to assess associations with soil type at the case residence. IB cases were identified through the distribution of the orphan drug Human Botulism Immune Globulin Intravenous for treatment of IB by state and national surveillance systems and were subsequently confirmed by laboratory testing. IB incidence by county was calculated as the number of IB cases divided by the number of live births in the county from 2000 to 2019. Cases were spatially mapped and assigned to soil types using the US Department of Agriculture's online soils database. Possible association with soil type was evaluated with the Chi-squared test. We identified a rectangular area consisting of 17 contiguous counties in Delaware, Maryland, New Jersey, New York, and Pennsylvania, approximately 80 km by 250 km, in which the 20-year incidence of IB was nearly seven times greater than that of the remaining counties in those five states. Within this area, case residences were strongly associated with certain soil types ( P ≤ 0.003). From 2000 to 2019, IB occurred with disproportionate incidence in a rectangular area encompassing the lower Delaware and Raritan River Valley and parts of five adjacent states. Further investigation of the soils in counties from this area could assess whether C. botulinum is more prevalent in certain soil types and whether isolation of C. botulinum is more common in counties with higher IB incidence., Importance: Infant botulism occurs more frequently in 17 counties within and adjacent to the Delaware and Raritan River watersheds. This study should alert physicians and pediatricians in the area to the higher likelihood of encountering cases of this otherwise rare disease that manifests with constipation, poor feeding, loss of head control, weak suck/cry, generalized weakness, and descending bilateral paralysis.

Abstract Background The boreal forest is one of the largest biomes on earth, supporting thousands of species. The global climate fluctuations in the Quaternary, especially the ice ages, had a significant influence on the distribution of boreal forest, as well as the divergence and evolution of species inhabiting this biome. To understand the possible effects of on-going and future climate change it would be useful to reconstruct past population size changes and relate such to climatic events in the past. We sequenced the genomes of 32 individuals from two forest inhabiting bird species, Hazel Grouse (Tetrastes bonasia) and Chinese Grouse (T. sewerzowi) and three representatives of two outgroup species from Europe and China. Results We estimated the divergence time of Chinese Grouse and Hazel Grouse to 1.76 (0.46–3.37) MYA. The demographic history of different populations in these two sibling species was reconstructed, and showed that peaks and bottlenecks of effective population size occurred at different times for the two species. The northern Qilian population of Chinese Grouse became separated from the rest of the species residing in the south approximately 250,000 years ago and have since then showed consistently lower effective population size than the southern population. The Chinese Hazel Grouse population had a higher effective population size at the peak of the Last Glacial Period (approx. 300,000 years ago) than the European population. Both species have decreased recently and now have low effective population sizes. Conclusions Combined with the uplift history and reconstructed climate change during the Quaternary, our results support that cold-adapted grouse species diverged in response to changes in the distribution of palaeo-boreal forest and the formation of the Loess Plateau. The combined effects of climate change and an increased human pressure impose major threats to the survival and conservation of both species.

Simple Summary: During the last Ice Age, most European animals retreated into southern refuges (mainly the Iberian, Italian, and Balkan peninsulas) from which they recolonized central and northern countries after deglaciation. These medio-European territories may have subsequently acted as secondary centers of southward dispersion for many species. Acting both as a refuge and as an area of colonization from adjacent territories, Italy was the theater of complex biogeographical histories, as illustrated by current distributional patterns of odonates (damselflies and dragonflies). These patterns are a result of historical factors and current ecological conditions. Odonates need freshwater for their development, and their richness in Italy decreases southwards, both because of a decrease in precipitation and because of increasing distance from the mainland (peninsula effect). Biogeographical composition of Italian regions is influenced by climate, geographical distances and historical factors. In particular, biogeographical similarities between Italian regions and adjacent areas revealed multiple colonization patterns. After serving as a glacial refuge from which odonates may have colonized medio-European areas, Italy was in turn subject to complex colonization processes, that made its fauna biogeographically very complex, albeit not particularly rich. As a natural bridge between Europe and Africa, Italy occupies a prominent position to understand the biogeography of Europe. The influence of climatic, spatial, and historical factors on current patterns of species richness and turnover (i.e., inter-regional biogeographical differences) has been analyzed for 88 species occurring in 17 Italian natural regions. Use of multimodel inference showed that odonate richness decreased southwards in response to decreasing rainfall, as expected for animals that depend on freshwater for their development. Use of Mantel tests indicated that patterns of inter-regional similarities were influenced by both climate and geographical distances. These patterns, as highlighted using Non-Metric Multidimensional Scaling, indicate a role for historical factors. Biogeographical similarities between Italian regions and adjacent areas revealed multiple colonization pathways. These results, coupled with the overall southward decrease in species richness, suggest that, after serving as a Pleistocene refuge from which odonates may have colonized medio-European areas, Italy was in turn subject to colonization from north to south. This resulted in Italian odonate fauna being less species rich compared to faunas in the medio-European territories, but also being biogeographically very complex. [ABSTRACT FROM AUTHOR]

We developed a new time-calibrated tree incorporating primarily endemic along with some cryptic Ryukyu islands cicada data, following the recent publication of global cicada data by Marshall et al. (2018), Łukasik et al. (2018), Simon et al. (2019), Price et al. (2019), and Hill et al. (2021). A total of 352 specimens were analyzed using BEAST v1. X software with a relaxed clock model. Fossil calibrations as old as Triassic were adopted largely following Johnson et al. (2018) and Moulds (2018), and a Quaternary geological event calibration was adopted following Osozawa et al. (2012, 2021b) and input into BEAST v1. X. Our timetree suggests that Tettigarctidae had a cicada basal lineage as old as 200.63 Ma, with Derotettiginae the next oldest lineage at 99.2 Ma. Tibicininae is a sister of the remaining subfamilies of Tettigomyiinae, Cicadettinae, and Cicadidae, and their species level differentiation and radiation began at 40.57 Ma. The Cicadinae clade consists of specific tribes with parapheletic relationship, and the vicariance and adaptive radiation generated many cryptic species in each tribe. We estimated base substitution rate as a function of age, and the result strongly indicates an exponential increase of base substitution rate in recent geologic time. The consequent increase in cicada biodiversity, including generation of cryptic species in the Ryukyu Islands and surroundings, may have been driven by the generation and spreading of C4 grasses and coeval Quaternary climate change.

Retrospective sea-level mapping advances a promising geographic solution to the longstanding mystery about when, where, and how the first Americans crossed over from Asia. A paleotopographic reconstruction accounting for Glacial Isostatic Adjustment digitally explores an archipelago about 1400 km long that likely existed from $>$30,000 BP to 8000 BP. Here the authors examine this Bering Transitory Archipelago in regard to established hypotheses—Clovis-first, Ice-free (deglaciation) Corridor, Kelp Highway, and Beringian Standstill hypotheses—and a new Stepping-Stones hypothesis. Scores of islands at that time would meet all requirements previously proposed for a viable hypothesis: a source population in Asia, a pathway with abundant sustenance, settlements in North America soon after but not before, and an isolated sanctuary where Beringians could have become genetically distinct.

The Hirnantian carbon isotopic excursion (HICE) was characterized by a positive δ13C excursion (up to ∼ + 7‰) of oceanic dissolved inorganic carbon (DIC). However its mechanism remains controversial, impeding our understanding of this global event and its environmental significance. Here, we conducted a comprehensive analysis of global carbon-isotope records, based on 65 paleogeographically-widely distributed sections (4612 carbon-isotope data), documenting a steep oceanic DIC δ13C water-depth gradient (e.g., a 4.6‰ offset in the HICE excursion magnitude within Laurentia) during the Hirnantian Stage. We propose a hybrid hypothesis that the HICE records a shift toward more positive values owing to a large glacio-eustatic fall (>100 m) under the herein-identified steep δ13C water-depth gradient, with potential contributions from global-ocean δ13C DIC changes and authigenic carbonates. This study provides the first large-data evidence for a widely density-stratified ocean during the Hirnantian Glaciation, with implications for reconstructions of ocean circulation and the carbon cycle during the Early Paleozoic. [ABSTRACT FROM AUTHOR]

In 1976 M.W. Mahaffy published a simple model for an ice sheet which allowed for time-varying accumulation rates and which did not make the usual steady state assumption that the ice sheet has a constant height. For this reason his model should be of interest to creation researchers, who could conceivably use it to model the rapid growth of a post-Flood ice sheet. This paper explains the theory and assumptions behind Mahaffy’s model, as well as mathematician Ed Bueler’s clever solution for the case of a shallow ice dome with a frozen base, resting on level ground. The results from the Mahaffy/Bueler solution are compared with the results from Larry Vardiman’s ice sheet model, and limitations of the Mahaffy model are discussed, as are the logical next steps in creation ice core research. [ABSTRACT FROM AUTHOR]

Seasonal and long-term variability of the ice age and concentration in the Japan Sea is analyzed on the base of all available information for 1960–2019. The highest variability of ice concentration is localized in the area with concentration 7–8 points (70–80 %) and follows to shifts of this area: form north to south in early winter and back to the north in late winter. The highest variability of ice age is associated with the area of young ice (age 1–3 points), where influence of melting or freezing on the ice thickness is the greatest. The areas of in-phase and out-phase variability of the ice age and concentration are identified and compared by analysis of standard deviations and 3 the first eigenvectors for restored mid-month fields of ice cover in December-May. Contributions of 3 the first empirical orthogonal functions (EOF) to total variability of the ice cover are determined. Cyclics with periods of 9–12, 2–4, and sometimes 15–16 and 4–6 years are found in variation of EOFs for the ice age and concentration; besides, the 5–7 years periodicity occurs in the ice age spectra for December, January and April.

Shorea parvifolia (Dipterocarpaceae) is a widely distributed tree species which is important in terms of ecosystem functioning as well as forestry in Southeast Asia. During glacial periods, substantial precipitation decline is believed to have occurred in Southeast Asia, which considerably changed the distribution of the species. Repeated glacial and inter-glacial fluctuations were found to have influenced the genetic structure of the species, which is important to know for conservation and sustainable use. Leaf samples were collected from 18 populations covering most of the natural distribution of this species including the Malay Peninsula, Sumatra, and Borneo Islands. We investigated these samples using sequence data for eight chloroplast DNA (cpDNA) regions and 14 nuclear EST-SSR loci. The nucleotide diversity of cpDNA is higher in Malay Peninsula populations but the genetic diversity of nuclear DNA is higher in Borneo populations. The genetic structure revealed by nuclear DNA clearly separated Borneo populations from the rest, with an FST value of 0.150, while the genetic structure obtained from cpDNA was less pronounced (FST value = 0.136). Tajima's D and Fu and Li's D* for cpDNA showed statistical significance only in populations from Borneo. These results suggested that there has been recent population expansion of S. parvifolia in Borneo. [ABSTRACT FROM AUTHOR]

The work contains the analysis of possible distributions of aerosol impurities through the glacier depth in those regions of Antarctica, where synoptic maps have shown stabilization of cyclones; and based on this analysis a methodology has been proposed for the determination of climatic parameter changes (average temperature and atmospheric precipitation amount) over a long time period. The main sources of the impurities in the glaciers of Antarctica are marine and continental aerosols, carried by meridional circulation of air masses. The annual concentration of chemical impurities, carried from both ocean and continent, and fallen on the glacier with rain or snow, is approximately the same over a long time period, if the glacier is located in a region of stable cyclonic activity. In this case, for the analysis, ice cores are taken continuously through the glacier depth. Linear sizes of all samples are similar. The quantity of annual layers in the sample is determined based on the age of the lower and upper levels in the glacier, from where the sample is taken. The thickness of the annual ice layer in the glacier is determined by the amount of fallen atmospheric precipitation and ablation processes. Consequently, all samples correspond to the periods of both equal and different durability. The quantity of annual layers in the sample (n) characterizes the amount of atmospheric precipitation of the corresponding period. Changes in the impurity concentrations from sample to sample are connected with the relative change in temperature of the corresponding periods. Then the two parameters, the number of annual layers, n, and the layer impurity content, C, have been determined experimentally in each sample. Based on these two parameters, a new technique has been proposed that allows determination of approximate temperature and precipitation changes over the time period, equal to the age of the studied glacier.

Understanding the population dynamics of megafauna that inhabited the mammoth steppe provides insights into the causes of extinctions during both the terminal Pleistocene and today. Our study area is Alaska's North Slope, a place where humans were rare when these extinctions occurred. After developing a statistical approach to remove the age artifacts caused by radiocarbon calibration from a large series of dated megafaunal bones, we compare the temporal patterns of bone abundance with climate records. Megafaunal abundance tracked ice age climate, peaking during transitions from cold to warm periods. These results suggest that a defining characteristic of the mammoth steppe was its temporal instability and imply that regional extinctions followed by population reestablishment from distant refugia were characteristic features of ice-age biogeography at high latitudes. It follows that long-distance dispersal was crucial for the long-term persistence of megafaunal species living in the Arctic. Such dispersal was only possible when their rapidly shifting range lands were geographically interconnected. The end of the last ice age was fatally unique because the geographic ranges of arctic megafauna became permanently fragmented after stable, interglacial climate engendered the spread of peatlands at the same time that rising sea level severed former dispersal routes.

The geometry of unconformities carved by deep time ice sheets is often obscured and restricted by discontinuous exposure, or outcrop conditions that do not readily permit the examination of glacial unconformities (for example, steeply dipping strata). Here, we present new uncrewed aerial vehicle (UAV) data from selected outcrops across northern, central and southern Namibia to shed further light on the nature of the basal Dwyka Group unconformity. This includes the onlap relationship of basal diamictites onto the Gomatum palaeo-fjord system in northern Namibia, highly complex mapped ice flow orientations elsewhere in the northern Kaokoveld, previously undiscovered grooves along the Fish River area, and a set of subglacial grooves along the border with South Africa along the Orange River. In the latter two cases, photogrammetric methods integrating orthophotos and digital elevation models reveal the presence of subglacial grooves. Furthermore, subglacial grooves often show different orientations to striations and fabrics measured in overlying diamictites, raising fresh questions about the nature of small-scale flow variations beneath Late Palaeozoic ice sheets. [ABSTRACT FROM AUTHOR]

As a natural bridge between Europe and Africa, Italy occupies a prominent position to understand the biogeography of Europe. The influence of climatic, spatial, and historical factors on current patterns of species richness and turnover (i.e., inter-regional biogeographical differences) has been analyzed for 88 species occurring in 17 Italian natural regions. Use of multimodel inference showed that odonate richness decreased southwards in response to decreasing rainfall, as expected for animals that depend on freshwater for their development. Use of Mantel tests indicated that patterns of inter-regional similarities were influenced by both climate and geographical distances. These patterns, as highlighted using Non-Metric Multidimensional Scaling, indicate a role for historical factors. Biogeographical similarities between Italian regions and adjacent areas revealed multiple colonization pathways. These results, coupled with the overall southward decrease in species richness, suggest that, after serving as a Pleistocene refuge from which odonates may have colonized medio-European areas, Italy was in turn subject to colonization from north to south. This resulted in Italian odonate fauna being less species rich compared to faunas in the medio-European territories, but also being biogeographically very complex.

The westerly jet (WJ) is an important component of atmospheric circulation, which is characterized by prominent seasonal variations in intensity and position. However, the response of the WJ over Asia during the Last Glacial Maximum (LGM) is still not clear. Using general circulation model experiments, the seasonal behaviors of the WJ over central Asia and Japan are analyzed in this paper. The results show that, compared to the present day (PD), the WJ presents a complicated response during the LGM, both in intensity and position. Over central Asia, it becomes weaker in both summer and winter. But over Japan, it is enhanced in summer but becomes diminished in winter. In terms of position, the WJ over central Asia shifts southward in both summer and winter, whereas the WJ over Japan moves southward in summer but does not change obviously relative to PD in winter. Such WJ changes are well explained by meridional temperature gradients in high troposphere, which is closely linked to seasonal thermal anomalies over the Tibetan Plateau (TP). Despite cooler LGM conditions, the anomalous warming center over the TP becomes stronger in summer. Derived from the heat budget equation, the stronger heating center is mainly caused by the weaker adiabatic cooling generated from ascending motion over the area south of the TP. In winter, the cooling over the TP is also strengthened, mostly owing to the subsidence-induced weaker adiabatic heating. Due to the importance of the WJ, the potential role of TP thermal effects should be a focus when explaining the East Asian climate change during the LGM. [ABSTRACT FROM AUTHOR]

MtDNA-based phylogeography has illuminated the impact of the Pleistocene Ice Age on species distribution dynamics and the build-up of genetic divergence. The well-known shortcomings of mtDNA in biogeographical inference can be compensated by integrating multilocus data and species distribution modelling into phylogeography. We re-visit the phylogeography of the Italian crested newt (Triturus carnifex), a species distributed in two of Europe's main glacial refugia, the Balkan and Italian Peninsulas. While a new 51 nuclear DNA marker dataset supports the existence of three lineages previously suggested by mtDNA (Balkan, northern Italy and southern Italy), the nuclear DNA dataset also provides improved resolution where these lineages have obtained secondary contact. We observe geographically restricted admixture at the contact between the Balkan and northern Italy gene pools and identify a potential mtDNA ghost lineage here. At the contact between the northern and southern Italy gene pools we find admixture over a broader area, as well as asymmetric mtDNA introgression. Our species distribution model is in agreement with a distribution restricted to distinct refugia during Pleistocene glacial cycles and postglacial expansion with secondary contact. Our study supports: (1) the relevance of the north-western Balkan Peninsula as a discrete glacial refugium; (2) the importance of north-eastern Italy and the northern Apennine as suture zones; and (3) the applicability of a refugia-within-refugia scenario within the Italian Peninsula. [ABSTRACT FROM AUTHOR]

The paper presents preliminary results of data processing of special ship observations of ice cover in the Arctic Basin between Franz Josef Land and the North Pole in summer 2018. Distribution of total ice concentration and ice age on the route of navigation of the nuclear icebreaker «50 let Pobedy» is shown. Comparatively to 2006-2011, amount of old ice in this area increased, however average ice thickness dramatically decreased. Mean thickness of level old ice in 2018 was 160 cm, which is 65 less than in 2006-2011 years of observations, and 90 cm less than in 1991-1996. Mean thickness of first-year ice in 2018 was 90 cm, which is 35 cm less than observed in 2006-2011 and 60 cm less than in 1991-1996.

The paper presents a short review of modern technologies for sea ice thickness measuring, the experience of operation with ship-based television complex (STK), and the program for automatic sea ice thickness monitoring system STK-K. The key moment for operative satellite ice condition forecasts in active navigation areas is the ice charts validation. For qualitative ice charts validation is using the real ice thickness data. The general purpose of STK-K program (automatic sea ice thickness monitoring system) is transition from temporary local observations to real-time and large-area monitoring system. The STK-K program will provide the operative data-array of the ice thickness values for the qualitative and detailed ice charts validation.

Traits in Upper Palaeolithic art which are also seen in the work of talented artists with autism, including most obviously an exceptional realism, remain to be explained. However any association between the famously evocative animal depictions created in the European Upper Palaeolithic and what is commonly seen as a ‘disorder’ has always been contentious. Debate over these similarities has been heated, with explanations ranging from famous works of Upper Palaeolithic art having been created by individuals with autism spectrum conditions, to being influenced by such individuals, to being a product of the use of psychotropic drugs. Here we argue that ‘autistic traits’ in art, such as extreme realism, have been created by individuals with a cognitive extreme of local processing bias, or detail focus. The significance of local processing bias, which is found both as a feature of autism spectrum conditions and in artists with exceptional talent at realistic depiction who aren’t autistic, has implications for our understanding of Upper Palaeolithic society in general, as well as of the roles played by individuals with autism spectrum conditions.

Ice ages constitute a significant part of Earth's climate history with the first signs of widespread ice sheets occurring at about 2.4 billion years ago. In 2004, a nearly 450 metres thick accumulation of seafloor sediments on the submarine Lomonosov Ridge in central Arctic Ocean was drilled by the international Arctic Coring Expedition (ACEX). This geological archive has provided insights into the long-term history of the Arctic Ocean back to 56 million years. The first signs of extensive sea ice along the Arctic coasts appear 47.5 million years ago (Ma), while evidence for the type of pack ice we have today that survives more than one season occurs first 15-13 Ma. The Earth's climate changed mode at about 2.6 Ma. Cold periods, characterized by large ice sheets covering the Northern Hemisphere, were intervened by warmer periods with climates more similar of today. These glacial-interglacial cycles were largely controlled by changes in solar insolation resulting from cyclical variations in Earth's orbit around the Sun. In this article, I tell the personal story of how we mapped the Lomonosov Ridge and found evidence supporting a controversial hypothesis of the existence of kilometre-thick floating ice shelves in the Arctic Ocean during past glaciations. [ABSTRACT FROM AUTHOR]

The main tenet of this article is to show how the ice, so visually dominant in the High Arctic, is also a prominent life force. The ice is never still and as it moves, melts or freeze, it deeply affects human and animal life in the region; conversely the diverse life-forms affect the icy environment in their own way and tempo. This interplay exposes the geo-social relations at the centre of this article, taking off from the gradual retraction of the ice after the last Ice Age, opening up for human movement and settlement in High Arctic America and eventually in Thule (Avanersuaq), in Northwest Greenland. Today some 750 people live there as hunters in the unsurpassable old hunting style, yet also as modern as anybody when it comes to outlook. Through brief discussions of particular periods, from the "discovery" of the Inughuit in 1819 and until the present, it is shown how deeply their life is implicated in the living ice, for better and for worse. The ice emerges as a refrain that holds the landscape together. The argument is based both in historical research and in regular anthropological fieldwork in the region over ten years 2007-2017. [ABSTRACT FROM AUTHOR]

The assumption of a stationary global signal linked to El Niño–Southern Oscillation (ENSO) events is often used in paleo-ENSO proxy data interpretation. This paper attempts to investigate whether the assumption is valid during the last glacial maximum (LGM) over the region 60°S–90°N, 60°E−60°W. Using four models within phase 3 of the Paleoclimate Modeling Intercomparison Project framework that well reproduce ENSO-induced variabilities, differences from the preindustrial period to LGM in the ENSO-related sea surface temperature pattern and its impacts are investigated. Compared to the preindustrial period, the ENSO impacts are revealed to weaken and shift eastward during the LGM. According to multimodel medians, ENSO impacts on precipitation and near-surface air temperature are attenuated over most regions of concern, with percentage changes in both parameters averaging −21% for the whole region; the ENSO-induced Pacific–North America (PNA) teleconnection pattern is weakened, manifested by the 41% diminished center over the North Pacific and the almost vanished activity centers over the continent. Spatially, there is a zonal contraction of 13° for the sea surface warming of ENSO, as well as eastward migration over 10° for the ENSO-induced positive precipitation anomaly center over the tropical Pacific and the PNA teleconnection pattern outside the tropics. The aforementioned changes are linked to the altered climatic background during the LGM, which features a 16° eastward shift for the Pacific Walker circulation rising branch and a weakened waveguide in the midlatitudes. The results suggest that the hypothesis of stationary ENSO impacts should be applied cautiously to the past. [ABSTRACT FROM AUTHOR]