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Scientific knowledge advances by the discussions on hypotheses, methods, and results, wherein the contradictory plays a positive role developing new theoretical-methodological approaches. In a positive debate to the progress of the science, the agreements and disagreements must only permeate the scientific scope and based on ethics to be away from the conflicts of interest. From this perspective, after knowing the submission titled Comments on Souza et al. (2022) "Recent geomorphological changes in the Paraiba do Sul delta, South America East Coast" to the journal Progress in Physical Geography: Earth and Environment (PPG), which addressed several issues concerning the results published in that article, we wrote this response to clarify the doubts related to the original paper. The comment's authors focus mainly on da Rocha et al. (2019), a locally published article that did not fully encompass the complexity of processes and geomorphological dynamics related to the delta evolution. Furthermore, it did not present the parameters used in the geochronological analyses in accordance with the international literature. Finally, the discussions presented in the original article contribute to advances in knowledge about the responses of the Paraíba do Sul delta to the Little Ice Age. [ABSTRACT FROM AUTHOR]

This paper aims to reconstruct the alluvial activity for the Lilas river, the second-largest catchment of Euboea Island (Central Western Aegean Sea), for approximately the last three and a half millennia. The middle reaches (Gides basin) exhibit several historical alluvial terraces that were first recognised in the 1980s but have remained poorly studied, resulting in uncertain chronological control of palaeofluvial activity. In order to reconstruct the past fluvial dynamics of the Lilas river, a ca. 2.5 m thick stratigraphic profile has been investigated for granulometry and magnetic parameters. Absolute dating of the sediments was possible by applying Optically Stimulated Luminescence (OSL). The results reveal: (i) two coarse-grained aggradational episodes dated from the Mycenaean/Early Iron Age and the Roman periods, respectively, (ii) a phase of rapid fine-grained vertical accretion corresponding to the Late Byzantine to early Venetian periods, (iii) potential evidence for final alluvial deposition from the Little Ice Age/Ottoman period, and (iv) two major incision episodes inferred from Ancient Greek times and most of the Byzantine period. Based on the published core material, the paper also evaluates the direct impacts of the Late Holocene alluviation recorded mid-stream on the fluvial system situated downstream in the deltaic area. Sediment sourcing is attempted based on the magnetic properties of the catchment lithology and of alluvium collected upstream along the main stream bed. Finally, the present paper discusses the possible links between Late Holocene hydroclimatic oscillations and the aggradational/incision phases revealed in the Gides basin. Correlations are attempted with regional palaeoclimate records obtained for the Aegean. In addition to climatic variability, anthropogenic factors are considered: specific land use for agricultural purposes, in particular during the Mycenaean period, the Roman and the Late Byzantine/Early Venetian periods, might have enhanced sediment deposition. Archaeological information and pollen records were also evaluated to reconstruct regional land-use patterns and possible impacts on soil accumulation over the last 3.5 millennia. [ABSTRACT FROM AUTHOR]

This paper presents continuous, high resolution fossil pollen and microcharcoal records from Bo Langvlei, a lake in the Wilderness Embayment on South Africa's southern Cape coast. Spanning the past ~1300 years and encompassing the Medieval Climate Anomaly (MCA; c. AD 950–1250) and the Little Ice Age (LIA; c. AD 1300–1850), these records provide a rare southern African perspective on past temperature, moisture and vegetation change during these much debated periods of the recent geological past. Considered together with other records from the Wilderness Embayment, we conclude that conditions in the region during the MCA chronozone were – in the context of the last 1300 years – likely relatively dry (reduced levels of Afrotemperate forest pollen) and perhaps slightly cooler (increased percentages of Stoebe -type pollen) than present. The most significant phase of forest expansion, and more humid conditions, occurred during the transition between the MCA and the most prominent cooling phase of the LIA. The LIA is clearly identified at this locality as a period of cool, dry conditions between c. AD 1600 and 1850. The mechanisms driving the changes observed in the Bo Langvlei pollen record appear to be generally linked to changes in temperature, and changes in the influence of tropical circulation systems. During warmer periods, moisture availability was higher at Bo Langvlei, and rainfall was perhaps less seasonal. During colder periods, precipitation resulting from tropical disturbances was more restricted, resulting in drier conditions. While increased precipitation has been reported during the LIA from Verlorenvlei in the Western Cape as a result of an equatorward displacement of the westerly storm-track at this time, the opposing response at Bo Langvlei suggests that any increased influence of westerlies was insufficient to compensate for the concurrent reduction in tropical/local rainfall in the region. [ABSTRACT FROM AUTHOR]

The climate variability and related sea-level changes during the Holocene are still under discussion, especially in a regional context. Very little information comes from the southern and south-eastern Baltic coast. The aim of the paper is to gain insight on the history of regional environmental changes, particularly sea-level and storminess, and their driving forces. The investigations were located on a peatland on the coast of Puck Lagoon (Gulf of Gdańsk, southern Baltic Sea). The analysis of peat core comprised: radiocarbon dating, analysis of stable isotopes 18O and 13C and chemical components, as well as palynological and diatomic studies. Results showed the 1.0 m peat section accumulated over 1500 years, with a time resolution of 100 years per sample. The average water level in the Puck Lagoon rose by ca. 0.85 m during the last 1500 years in a cyclic mode, with a period cycle of ca. 600–550 years and an amplitude not exceeding 0.5 m. The accelerated sea level rise and frequent storminess occurred during the first half of the Dark Ages (1500−1300 years b2k) and LIA (750−450 years b2k) and since the beginning of the 20th century. Recognized environmental changes are well correlated with both temperature changes in the North Atlantic and changes in total solar irradiance, suggesting synchronous Northern Hemisphere-wide fluctuations. The solar forcing was an important constituent of natural climate variability in the past and of forcing climate warming during modern times - after the Little Ice Age. [ABSTRACT FROM AUTHOR]

Palaeoclimatic records from southern tip of South America during the Last Holocene, indicate important climate intervals, such as the Medieval Climate Anomaly and Little Ice Age, which offered new scenarios to hunter-gatherer groups who inhabited the region. The aim of this paper is to explore the social practices carried out by hunter-fisher-gatherer societies of the southern part of the Atlantic Coast of Tierra del Fuego island (53–55°S, 66–74°W) in order to deal with these environmental changes. From our perspective, foragers have played an active role in designing strategies to cope with environmental fluctuations. Consequently, we argue that in a context of ecological uncertainty, these societies would have developed flexible strategies in terms of subsistence, technology and settlement patterns. In order to test this proposal, zooarchaeological and technological analysis of different archaeological assemblages dated between the 1300 to 220 BP were undertaken. The results show that these hunter-fisher-gatherer societies exploited a broad range of faunal resources using a versatile technology which encompassed tools with low production values and high use values. Likewise, the analysis of landscape organization revealed a settlement strategy centered on the most productive habitats, which were preferentially reoccupied. We suggest that these strategies, supported by cumulative knowledge and material conditions, could have enhanced social resilience and sustainability. [ABSTRACT FROM AUTHOR]

In this paper, we undertake a high-resolution palynological analysis of a sediment core covering the last 1500 years obtained from Lake Ayakum in the northern Tibetan Plateau, to improve the understanding of regional climate fluctuations and their driving mechanisms. The pollen spectra are dominated by herbaceous species such as Artemisia , Chenopodiaceae, Cyperaceae and Poaceae, which grew in various alpine desert settings. Four pollen assemblage zones are identified using stratigraphically constrained cluster analysis, representing climate history at different stages. The Artemisia /Chenopodiaceae (A/C) ratio and axis score of the first principal component are used to infer regional moisture conditions and reveal a temporal pattern that is consistent with various records from central Asia. The source of Cyperaceae pollen is mainly from marsh wetlands distributed around the lake, which responded sensitively to the lake level fluctuations. In contrast, arboreal pollen is mainly a long-distance transported component, reflecting changes in regional vegetation. Our findings show that the northern Tibetan Plateau experienced relatively wet conditions during the Dark Age Cold Period and the Little Ice Age, while relatively dry conditions occurred during the Medieval Warm Period and the last two centuries. Fluctuations in moisture levels are broadly consistent with moisture records elsewhere in western China, and show a good correlation with phase changes of the North Atlantic Oscillation. The climate changes in the northern Tibetan Plateau are supposed to be primarily triggered by the NAO phases through south-north migrations of the mid-latitude westerlies during the late Holocene. • Fossil pollen based 1500-year vegetation and climate changes on the northern Tibetan Plateau. • Major pollen species were analyzed and interpreted in terms of regional moisture variations. • Four vegetation and climate stages during the late Holocene were determined accordingly. • NAO phases affected northern TP climate through south-north migrations of the westerlies. [ABSTRACT FROM AUTHOR]

This paper aims to reconstruct paleoenvironmental conditions and sea-level changes over the last 5500 years. Multi-proxy investigations of sediment types, foraminiferal records, geochemistry parameters and paleotidal elevation changes were conducted on a short sediment core KHAR1 (225 cm long) retrieved from the intertidal area of the Al-Kharrar Lagoon. The sediment age was determined using 14C dating of marine mollusk shells. Results showed that two prominent warming events during AD 750–1500 and 1750–present and a cooling event during AD 1500–1750 were inferred from the variation of benthic foraminiferal composition in core KHAR1. Before 3000 BC interval, the core sediment was deposited under intertidal–subtidal conditions as indicated by the presence of terrestrial sediments (siliciclastic materials), a decrease in subtidal-deep species and a slight drop in the paleotidal elevation about 0.50 cm below the present lowest astronomical tide (LAT). From 3000 to 750 BC, deep-lagoonal species such as S. costigera, T. trigonula, T. serrulata and S. communis dominated this interval and co-occurred with a decrease in coarse sand and an increase in muddy substrates, indicating a prevalence of subtidal environmental conditions during the deposition of this interval. With the beginning of the 1st millennium, symbiotic (epiphytic) species started to increase, reaching the highest abundances between AD 800 and 1500. This increase in symbiotic species during the AD 800–1500 interval coincided with a stepwise increase in sea level and may indicate the prevalence of seagrasses associated with the occurrence of warm water due to climate warming prevailed in/around the lagoon during the deposition of this interval that corresponds to the 'Medieval Warm Period' (MWP). The MWP was followed by cooler (arid) conditions of the Little Ice Age (AD 1500–1750), causing a decrease in the abundance of the epiphytic species S. orbiculus and P. planatus (up to 14%) and a drop in paleotidal elevations. After this, the modern warming conditions prevailed until the present day. [ABSTRACT FROM AUTHOR]

This paper presents high-resolution (multi-decadal) paleoenvironmental data of the last 1400 years in the northwestern sector of the dry Puna, Jujuy Province (Argentina). This information results from the analysis of the diatom assemblies recovered from sediment core samples collected at Laguna Pululos (22°32'43'' S; 66°48'25'' W), a shallow lake located at 4557 m.a.s.l. In this work we present and discuss the main results regarding the species composition of the diatom assemblages, and the observed paleoenvironmental trends related to the main characteristics and chronology of the medieval climatic anomaly (MCA) and little ice age (LIA). The results of the study indicate the onset of very arid conditions between ~800 and 1500 AD, and a sharp change to moister conditions from the latter period until the end of the XIX century. Noteworthy, two periods could be recognized, one between 600 and 800 AD (the moistest phase of the last 1400 years), and between 1366 and 1463 AD (a particularly arid phase). These periods recorded in Laguna Pululos apparently shared characteristics with the MCA and LIA, although, showing differences with chronologies found in the North Hemisphere, with an extended span of the arid conditions during the MCA in comparison with other paleoenvironmental records of the Andes. [ABSTRACT FROM AUTHOR]

This paper explores variation in maize consumption among human societies in arid environments of central-western Argentina over the last 2500 years. Increasingly positive human d 13 C signatures suggest a high intake of C 4 resources (maize) until ca . A.D. 1400. After this time, the importance of maize in the diet drops and never reaches pre-Hispanic consumption rates, despite the known importance of maize to Inka and other late-prehistoric societies in the region. This decline appears to be related to colder temperatures during the Little Ice Age from the beginning of the 15th to the mid19th centuries. [ABSTRACT FROM AUTHOR]