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This paper presents the first results of palynological research from the Spila nad Procjepom cave, situated in the Mljet National Park, Croatia. The palynological data obtained, enables a partial insight into the local vegetation cover, temporal changes in the vegetation during the accumulation of studied deposits (at ca. 3500 cal years BP), and post-depositional processes that influenced the palynomorph assemblage. Results of palynofacies analysis indicate changes from fluvial (channel deposits), through palustrine to terrestrial environments. Although the interpretation of changes in plant cover, due to the lack of statistical significance, should be taken with caution, preserved pollen types confirm the dominance of the Mediterranean evergreen forest vegetation on Mljet island. Moreover, a high proportion of non-arboreal pollen (NAP) indicates some level of forest degradation, ranging from Mediterranean open forest to degraded maquis. Abundant charcoal additionaly confirms that the cave was inhabited by humans. [ABSTRACT FROM AUTHOR]

Impact craters are formed by collisions of cosmic bodies moving with hypervelocity. The formation of these features is not restricted to the distant geological past; new structures are constantly being created and at least 13 confirmed impact craters and crater fields have formed during the Holocene alone. This short review paper: (1) introduces the basics of the impact cratering process to physical geographers and Quaternary geologists; (2) provides a short description of representative examples of such features (Morasko, Kaali, Kamil, Ilumetsa); and (3) discusses the similarities and differences among very small craters, and contrasts these with larger impact structures. This manuscript may be useful to researchers planning to test whether a small Quaternary depression in the ground may be of impact origin. [ABSTRACT FROM AUTHOR]

This paper describes an approach assuming that already in the sea, based on the express analysis of visually similar cores of Arctic Holocene sediments and their comparison with dated and studied in detail cores of the regional sediments, it is possible to select a material that is promising for sequence stratigraphic correlation and paleoreconstructions. The range of lithological, colorimetric (CIE L*, CIE a*, and CIE b*), geophysical (magnetic susceptibility), and geochemical (Fe/Rb, Mn/Rb, and Ti/Rb) parameters is analyzed. The most informative characteristics include the CIE b* color coordinate, magnetic susceptibility, and Fe/Rb. [ABSTRACT FROM AUTHOR]

Recent climate and environment over the Tibetan Plateau (TP) have undergone significant changes, dominated by variations in the Westerlies and the Indian summer monsoon. However, long‐term shifts in atmospheric circulation during the transitional seasons are still lacking. Here we investigate the modern distribution of Tsuga pollen over the central‐western TP and confirm it as an indicator of variable atmospheric circulation in spring. By combining our Tsuga record from Taro Co with existing records in the Tsuga pollen source area, we suggest that a potential particle transport pathway from the southern slope of the Himalayas to the interior of the plateau appeared in the spring of the late Holocene. Our results show that the springtime atmospheric circulation over the southwestern TP during the early and late Holocene is closely related to the substantial remnants of ice sheets at northern high latitudes and the frequency of El Niño events, respectively. Plain Language Summary: The spring climate over the Tibetan Plateau (TP) is undergoing significant changes that yield profound impacts on environmental changes such as variations in vegetation phenology and alpine treeline. Knowledge of long‐term variations in atmospheric circulation during spring can improve the understanding of current climatic and environmental change and the projection of future variability. In this paper, we use an exotic pollen grain, which can be transported long distances in the air, as an indicator to trace the variability of spring atmospheric circulation over the TP. The results indicate that the spring meridional atmospheric circulation from the southern slope of the TP to its interior has been enhanced in the last four thousand years, which is mainly influenced by the frequency of El Niño events. Key Points: Spring atmospheric circulation change over the southwestern Tibetan Plateau (TP) during Holocene is reconstructedMeridional atmospheric circulation in spring over the southwestern TP is strengthened in the late HoloceneHigh‐(low‐) latitude forcing mainly influence the variations in spring atmospheric circulation during the early (late) Holocene [ABSTRACT FROM AUTHOR]

Despite the wealth of Late Pleistocene archaeology that exists across southern Africa's open landscape, it is routinely neglected in favour of rock shelter (re)excavation, biasing interpretation of human–environment interaction. This is compounded by the scarcity of open-air studies that use geoarchaeological methods to investigate the history and processes involved in their formation. The open-air archaeology of the Doring River Valley is an example of this, despite nearly a decade of dedicated study and publication. Consequently, there remains a limited and untested understanding of the valley's formation history. This paper rectifies this by providing a sedimentary context for the surface archaeology exposed across one of the Doring River Valley's artefact-baring localities, Uitspankraal 7 (UPK7). Characterisation, particle size, mineralogical, morphometric, and geophysical analysis of UPK7′s sand mantle resulted in the identification of four artefact-bearing sedimentary units, the aeolian and pedogenic processes involved in their formation, and their proposed order of deposition. This provides a stratigraphic, taphonomic, and environmental context against which chronometric dating and an analysis of the taphonomic, spatio-temporal, and technological composition of UPK7′s surface archaeology can be compared. This work is the first vital step towards understanding the depositional and behavioural history of a landscape, irrespective of context type. [ABSTRACT FROM AUTHOR]

Clues of climate change on the Alashan Plateau since the last glacial period (40 ka) are important for revealing the mechanism of desertification of middle-latitude deserts in the Northern Hemisphere (NH). Studies are still rare for the understanding of the specific relationship of climate changes between the Alashan Plateau and the global. Based on a systematic and comparative analysis of the existing research in China and the international academic community, this paper reviews the environmental evolution history of the Alashan Plateau since the last glacial period from the records of paleo-environment and geomorphological characteristics in different deserts of the plateau (e.g., Badanjilin, Tenggeli, and Wulanbuhe). From about 40 ka to the end of the last glacial maximum, the climate on the plateau was wetter than it is today, and to the end of the Pleistocene, the climate was generally dry and the aeolian activities were enhanced. However, the climate was arid during the whole last glacial period in the Wulanbuhe Desert, evidently different from the overall pattern of the plateau. The Tenggeli Desert was characterized by an arid climate in the early Holocene. The most controversial events for the Alashan Plateau are the drought events in the middle Holocene in the Badanjilin Desert. The role and impact of the westerlies and the East Asian Summer Monsoon (EASM) systems on the climate change of the desert and even the whole plateau is a vexed question that brings different views in different periods. There is still a lack of definite evidence representing the events of global environmental change that occurred on the plateau during the discussed period. The distinctive morphology of dune mountains and the distribution of sand dunes are mutually indicative of the direction and energy of wind systems on the plateau. It is suggested that appropriate wind energy is the significant key to the desertification in these middle-latitude deserts on the plateau. From a global-scale review of climate change, the desertification of the modern-scale sandy desert landscapes on the Alashan Plateau is generally related to the global glacial period and the cold and dry climate during the past 40 ka. [ABSTRACT FROM AUTHOR]

This paper develops a composite absolute paleointensity record for Holocene paleomagnetic secular variation (PSV) from central North America. Twelve full‐vector (inclination, declination, paleointensity) PSV records were assessed in order to build the composite record. Nine of the paleointensity records come from sediment paleomagnetic studies and are considered relative in intensity. Three of the paleointensity records come from absolute paleointensity measurements of archeological materials and lava flows. This paper develops a new method to normalize the sediment relative paleointensity records to the absolute intensity records. The final composite paleointensity record describes intensity variability over a region of Central North America delineated by 35°–48.6°N and 240.4–291.4°E (∼14° × 50°). This composite record shows a distinctive long‐duration (∼104 year) oscillation and a series of millennial‐scale intensity oscillations that are consistent over our study region. Plain Language Summary: This study develops a composite record of geomagnetic field intensity for the central North America for the last 8,000 years. This record is important for considering the total geomagnetic field variability I this region and its dynamo source(s). Key Points: We develop a new composite absolute paleointensity record for Holocene Central North AmericaWe develop a new renormalization technique to combine absolute paleointensity records and sediment relative paleointensity recordsThe final composite absolute paleointensity record has a distinctive long‐term trend and millennial‐scale variability [ABSTRACT FROM AUTHOR]

The North American Monsoon (NAM) is a critical component of the hydrologic cycle in southwestern North America. However, our understanding of the long‐term evolution of this monsoon system is incomplete due to a paucity of long‐term paleoclimatic records from the core and periphery of the NAM domain. C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) leverage a new compilation of Holocene proxy records to generate a new composite index of NAM evolution over the Holocene. They identify a relationship between NAM strength and the latitudinal temperature gradient over the Holocene. The authors suggest that shifts in the strength of the westerlies altered NAM convection via ventilation, a process whereby the large‐scale circulation imports low moist entropy air into the monsoon domain. These results highlight the importance of paleoclimatic records, especially from past "warm" intervals, for generating new insights about the evolution of regional monsoons. Plain Language Summary: The North American Monsoon is a circulation that brings summer rain to regions of the US southwest and western Mexico. Despite the fact that this circulation provides a majority of the precipitation in many parts of the arid southwest, we do not fully understand the factors that govern long‐term changes in this monsoon. A new paper by C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) uses proxy indicators of past summer rainfall, stretching from Central America to Arizona, to reconstruct changes in the monsoon over the geologic epoch known as the Holocene, or the last 11,000 years of Earth history. The results of this study suggest that Holocene changes in the temperature difference between the equator to pole, known as the "latitudinal temperature gradient," exerted an important influence over monsoon strength in the southwest. This has implications for the future of the summer monsoon, especially as the high latitudes of the northern hemisphere are expected to warm in the future. Key Point: The strength North American Monsoon tracks changes in the position of the midlatitude westerlies over the Holocene [ABSTRACT FROM AUTHOR]

The following paper addresses the study of those knapping processes occurred during the middle Holocene in Laguna de los Pampas (Central Pampean Dunefields, Buenos Aires), carried out through tecnomorphologic and technological (chaînes opératoires) studies of the lithic artifacts recovered in the surface of the Sector 2. The results obtained points to the employ of a wide diversity of raw materials, which sources are located at least 170 km away from the site, and among which stands the orthoquartzites and cherts from Tandilia. For these two rocks, as well as for the silicified dolomite, a direct acquisition is proposed. The production of blanks was mainly made by the unipolar and centripetal débitage. The presence of dull edges, reactivation flakes and exhausted cores, as well as the employment of the bipolar reduction, suggest an optimization in the exploitation of rocks. [ABSTRACT FROM AUTHOR]

The paper surveys the Quaternary (MN17-Q4) fossil record of Cricetinae in the Czech Republic and Slovakia with particular attention to the current glacial cycle (Q4: Vistulian-Holocene) and immediate history of extant taxa. Vast majority of records were reexamined using standardized techniques of morphometric analysis (in total 625 molars of Cricetus, 805 molars of small hamsters). Cricetus cricetus, recorded in 130 Q4 fossil communities, exhibits almost continuous appearance since the beginning of Vistulian, possibly with considerable range regressions during LGM and middle Holocene. It was recorded also in 27 Early Pleistocene (MN17-Q2) and 6 Middle Pleistocene (Q3) assemblages, with a small-sized form (Cricetus cricetus nanus) in MN17-Q1 stage and a mosaic of Q2-Q3 records exhibiting mostly excessively large size (C. c. runtonensis), similarly as the Vistulian items which are clearly larger than those of the post-LGM and early Holocene age. The appearance of hamster in fossil record shows a mosaic character suggesting temporal spatial and abundance fluctuations: in most sites it absents and in general, it appears as a rather rare sub-recedent element (in Q4 communities with overall dominance of mere 0.55% and this is valid also for its appearance in Early and Middle Pleistocene assemblages). Small hamsters arranged here in the genus Cricetulus (incl. Allocricetus) represent a constant element of the Early and Middle Pleistocene assemblages (43 sites in the Czech Republic and Slovakia). The items of Q4 record (21 communities) clearly differ from the Early to Middle Pleistocene form Cricetulus bursae by a consistently smaller size corresponding to extant species Cricetulus migratorius. The gap is quite distinct conforming even to the possible extinction of C. bursae during the Eemian interglacial followed by early Vistulian expansion of the extant species from its Asiatic range suggested by molecular phylogeography. We examined a question of possible appearance of Phodopus among the Q4 record of small hamsters, yet in our material, we did not succeed to confirm it. [ABSTRACT FROM AUTHOR]

Climate variability has probably affected the frequency and distribution of debris flows and snow avalanches throughout the Holocene. In this paper, we reconstruct the Holocene history of debris flows and snow avalanches by investigating outcrops in colluvial fans surrounding lake Anestølsvatnet in western Norway and sediment cores penetrating the lake-floor deposits. We made a detailed map of the surface deposits around the lake. The formation of a large end moraine that dams the lake was radiocarbon dated to 10,200-10,800 cal. yr BP, and correlates to the Erdalen event, a Preboreal glacial oscillation. There are colluvial fans and debris-flow paths and snow-avalanche paths eroded on the steep slopes around the lake. On the western slopes, the fans are dominated by snow avalanches, and on the eastern slopes by debris-flow activity. Three of the lake cores were taken distal to the largest avalanche fan on the western slope, Storeskreda ('Storeskreda' means 'the big landslide'). Clasts > 2 mm in the lake sediments are interpreted as traces of snow avalanches and sorted sand layers as being derived from debris flows. Loss-on-ignition and magnetic susceptibility measurements document an increased silt content in the lake sediments after c. 6000 cal. yr BP, probably due to the reappearance of local glaciers in the area. Our combined data from the onshore outcrops/pits and lake sediments shows almost continuous snowavalanche activity and debris-flow activity throughout the last 10,000 years. However, there may have been an increase in the snow-avalanche activity over the last 5000 years. [ABSTRACT FROM AUTHOR]

This paper reviews the distribution of Pinus koraiensis in the south of the Russian Far East in the past based on palynological and chronological data. The aim is to determine the chronological timing of the spatial migration of Pinus koraiensis and to correlate it with climate fluctuations explaining the changes of the geographical range of Pinus koraiensis in the south of the Russian Far East during the Marine Isotope Stages MIS 5 (127 000--71 000 BP), MIS 3 (57 000 BP -- 28 000 cal BP), MIS 2 (28 000--11 700 cal BP), and MIS 1 (11 700 cal BP -- to present). The consideration of the obtained pollen fossil data suggests that the range of Pinus koraiensis was in the south of the Russian Far East during MIS 5, as it was proved based on significant pollen grain percentage in the sediments of this age. Pinus koraiensis was widespread along with Pinus densiflora, Quercus, Ulmus, Juglans, Carpinus, and Phellodendron. During MIS 3, Pinus koraiensis was a component of birch-fir and birch-broadleaved forests. In MIS 2, Pinus koraiensis disappeared from the vegetation of this region. In the early Holocene, Pinus koraiensis expanded its range northward and again appeared in the vegetation of the south of the Russian Far East. Soon enough, it became one of the leading components in spruce-fir forests with Quercus and Ulmus. The increase in its proportion in the vegetation in the Holocene coincided mostly with the periods of warming climate from 11 700 to 11 500 cal BP, from 10 100 to 9300 cal BP, from 8800 to 5300 cal BP, from 4700 to 3500 cal BP, and from 2600 to 1800 cal BP. In the present case, the most diverse vegetation with Pinus koraiensis was typical of the Holocene optimum of the south of the Russian Far East from 8800 to 5300 cal BP. [ABSTRACT FROM AUTHOR]

The Bohai Sea is a semi-enclosed shallow shelf sea that has undergone a unique sediment source-to-sink process in the past. Despite this, our knowledge about the sediment budget, existence of depocenters and the factors controlling depocenter formation during the Holocene remains limited. This paper aims to address these gaps by estimating the Holocene marine deposit thickness and sediment budget in the Bohai Sea using high-resolution subbottom profiles. The results reveal that the mean thickness of Holocene marine deposits is approximately 7.8 m and a maximum thickness of 28 m was found in Jinzhou Bay. The Highstand System Tracts (HST) have a mean thickness of approximately 5.4 m and a maximum thickness of 25 m observed in the Jinzhou Bay. On the other hand, the Transgressive System Tracts (TST) have a mean thickness of approximately 2.5 m and a maximum thickness of 7 m in the north of the Laizhou Bay. The total accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons, consisting of 489.28 × 109 tons from the HST and 224.69 × 109 tons from the TST. Three deposit centers were identified and estimated to be approximately 299 × 109 tons, accounting for approximately 42 % of the total Bohai Sea sediments. The development of Holocene marine deposit centers was mainly influenced by the Tanlu Fault zone and water circulations. Based on preliminary estimates, it is suggested that roughly half of the sediments dispersed from the estuaries are preserved on the Bohai Sea shelf since the maximum flooding (∼7000 cal yr BP). This research provides valuable insights for the post-glacial sedimentary and geomorphic evolution of the Bohai Sea. • Holocene marine accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons. • Accumulation in HST is of ∼489.28 × 109 tons and that in TST is of ∼224.69 × 109 tons. • Three depocenters were identified and account for ∼42 % of the total accumulation. • Roughly half of the sediments were preserved on the shelf over the past 7000 years. [ABSTRACT FROM AUTHOR]

In recent years, more and more record-breaking extreme weather/climate events have been reported from the Asian monsoon region, which have caused tremendous loss of property and lives. In this paper, we analyzed the Asian summer monsoon (ASM) variability during the Holocene and evaluated future climate extremes in monsoonal China from a paleoclimatic view. We found a significant regime transition to more chaotic fluctuations, with enhanced decadal variability of the ASM since 6.6 ka BP. We suggested the gradual intensification of ENSO was responsible for enhancing the ASM variability since the late mid-Holocene. If the observed relationship of monsoon mean intensity, ENSO and decadal variability of the ASM in the past 11.2 ka continue to exist, enhanced decadal variability of ASM in the future warming world will be expected. As a result, the intensification of daily precipitation extremes, superimposed on enhanced decadal variability of ASM, might make the record-breaking extremes more frequent in the future, increasing the risk of climate-related disasters in China. [ABSTRACT FROM AUTHOR]

In tropical Africa, Late Pleistocene-Holocene climatic fluctuations heavily impacted the continental hydro-systems. The timing and magnitude of 'African Humid Period' hydrological dynamics (AHP; ~14.8 to ~5.5 ka BP) are not yet fully understood due to the extreme variability in African geomorphic patterns and the complex network of past air convergence boundary shifts. The investigation of the functioning of specific hydro-sedimentary basins is needed to improve our knowledge on the AHP spatial and chronological patterns over the continent. In this paper we present a revised Holocene lake level curve of Lake Abhe: an endorheic basin situated in the Afar Depression at the northern extremity of the East African Rift System (EARS). Located at the boundary of the Red Sea and the Indian and Atlantic Oceans' air moisture mass fluxes, the Lake Abhe watershed represents a system sensitive to changes in Northeast African hydro-climate. Based on numerous littoral lacustrine geomorphic features and 53 related radiocarbon ages on stromatolites and nearshore deposits, we have defined the main Holocene lake highstands proposing a detailed paleo-shoreline record. The first rise in water level is dated to ~11.1 ka cal. BP, while the Maximal Holocene Highstand Shoreline (~420 m a.s.l.) was rapidly reached around ~10 ka cal. BP. Evidence of the impact of the 8.2 ka North Atlantic cooling event is recognized with slow lake level regression until ~8.3 ka cal. BP and with an abrupt drop at ~8 ka cal. BP. The resurgence of humid conditions was recorded from ~7.7 ka cal. BP to ~4.6 ka cal. BP. Radiocarbon ages on littoral materials allow us to propose a Holocene subsidence rate of the Abhe basin axial valley. Furthermore, multiphase sill overflow incisions towards the downstream Hanle basin and transient fluvial connectivity with the upstream Ziway-Shala basin, indicate strong geomorphic controls on lake highstand elevations. In summary, Lake Abhe Holocene fluctuations are the result of combined hydro-climatic, tectonic and local geomorphic controls. However, the confrontation with others East African basins allows us to discuss the transport of moisture masses dynamics into the northern EARS during the Holocene. [ABSTRACT FROM AUTHOR]