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Recent global fire activity has highlighted the importance of understanding fire dynamics across time and space, with records of past fire (palaeofire) providing valuable insights to inform current and future management challenges. New records from the recent increase in palaeofire studies from Australia and surrounds have not been captured in any database for broader comparisons, and Australasia is poorly represented in current international databases used for global modelling of palaeofire trends. These problems are addressed by SahulCHAR, a new collection of sedimentary charcoal and black carbon records from Sahul (Australia, New Guinea, and offshore islands) and New Zealand. Data are stored in the OCTOPUS relational database platform, with a structure designed for compatibility with the existing Global Paleofire Database. Metadata are captured at site-level and observation-level, with observations including age determinations and charcoal or black carbon data. SahulCHAR Version 1 contains 687 records of charcoal or black carbon, including digitized data, unchanged and modified records from the Global Paleofire Database, and original author-submitted data. SahulCHAR is a much-needed update on past regional palaeofire compilations that will also provide greater representation of records from Sahul and New Zealand in future global syntheses. [ABSTRACT FROM AUTHOR]

Background: As fire regimes continue to evolve in response to climate change, understanding how fire characteristics have responded to changes in the recent past is vital to inform predictions of future fire events. Aims and methods: Using Fourier Transform Infrared (FTIR) spectroscopy, we assessed how fire intensity has changed in two fire-prone landscapes in south-eastern Australia: (1) the Blue Mountains; and (2) Namadgi National Park during the past 3000 years. Key results: Higher aromatic/aliphatic ratios suggest increased high-intensity fire frequency in sediments at the surface of both cores. Increases in the frequency of extreme drought periods, coupled with the change in vegetation and anthropogenic ignitions following colonisation, could have increased the frequency of high-intensity fires in the past ~200 years. Conclusions: FTIR spectroscopy can be used in sediment deposits to infer that the frequency of high-intensity fire events has increased in the past 200 years compared to the previous ~3000 years. Implications: These results are important for understanding how past fire regimes have responded to climate, people and vegetation shifts in the past ~3000 years and can be used to inform models for future predictions and management strategies. Fourier Transform Infrared (FTIR) spectroscopy was applied to sediment deposits in southeastern Australia. The aromatic/aliphatic ratio was used as a proxy for high-intensity fires. The increased frequency of high-intensity fire events could result from interactions between climate, people, and vegetation. The existing fire record was extended by centuries to millennia. [ABSTRACT FROM AUTHOR]

Australian conservation targets commonly focus on preserving a vaguely defined ecological baseline, often conceptualised as a pre-European, 'natural' state. For instance, environmental legislation protects 'Endangered Ecological Communities' (EECs), which purportedly represent remnants of naturally occurring biota. However, EECs are often classified without long-term data, making it unclear as to whether the community being protected is indeed 'natural'. In this essay, we use history, ecology, and geography to map the long-term socio-environmental evolution of Sydney's freshwater wetland EECs, which were once key features of Australia's biggest city. Our data show that today's remnant wetlands are different from those of the early 1800s, highlighting how quickly landscapes can be misremembered. We encourage a reimagining of these wetlands not as snapshots of the past, but as human-impacted places with educational, ecological and historical importance. Our work emphasises the relevance of long-term, cross-disciplinary data for effective conservation, while highlighting limitations in post-colonial land management. [ABSTRACT FROM AUTHOR]

The drivers of fire regimes prior to the European occupation of Australia are still contentious, with some advocating regimes dominated by anthropogenic ignitions and others advocating a climate source or mixture of these elements. Here, we examine an 850-year history of fire regimes at Lake Werri Berri in south-east Australia, prior to and following European occupation. Macroscopic charcoal and FTIR spectroscopy were used to infer broad changes of the fire regime in proximity to the lake. We found little change through much of the 850-year period and most interesting, no apparent change following the initial displacement of Indigenous peoples and the introduction of farming and woodcutting to the region by Europeans. From the mid-20th Century onwards, there was an increase in both area burnt and fire severity or intensity, likely the result of increased fuel load and connectivity following an extended period of increased precipitation and heavier recreational land usage, which likely led to an increase in anthropogenic ignitions. [ABSTRACT FROM AUTHOR]

Ethnographic observations suggest that Indigenous peoples employed a distinct regime of frequent, low-intensity fires in the Australian landscape in the past. However, the timing of this behaviour and its ecological impact remain uncertain. Here, we present detailed analysis of charcoal, including a novel measure of fire severity using Fourier transform infrared (FTIR) spectroscopy, at a site in eastern Australia that spans the last two glacial/interglacial transitions between 135–104 ka and 18–0.5 ka BP (broadly equivalent to Marine Isotope Stage (MIS) 6-5 and 2-1, respectively). The accumulation of charcoal and vegetation composition was similar across both periods, correlating closely with Antarctic ice core records, and suggesting that climate is the main driver of fire regimes. Fire severity was lower over the past 18,000 years compared to the penultimate glacial/interglacial period and suggests increasing anthropogenic influence over the landscape during this time. Together with local archaeological records, our data therefore imply that Indigenous peoples have been undertaking cultural burning since the beginning of the Holocene, and potentially the end of the Last Glacial Maximum. We highlight the fact that this signal is not easily discernible in the other proxies examined, including widely used charcoal techniques, and propose that any anthropogenic signal will be subtle in the palaeo-environmental record. While early Indigenous people's reasons for landscape burning were different from those today, our findings nonetheless suggest that the current land management directions are based on a substantive history and could result in a reduction in extreme fire events. [ABSTRACT FROM AUTHOR]

The human visual system is tasked with the problem of extracting information about the world from images that contain a conflated mixture of environmental sources and optical artifacts generated by the focal properties of our eyes. In most contexts, our brains manage to distinguish these sources, but this is not always the case. Recent work showed that shading gradients generated by smooth three-dimensional (3D) surfaces can elicit strong illusory percepts of optical defocus 1,2 — the perception of illusory blur is only eliminated when the surface appears attached to self-occluding contours 3 , surface discontinuities 1 , or sharp specular reflections 1,2 , which all generate sharp ('high spatial frequency') image structure. This suggests that it should also be possible to eliminate the illusory blur elicited by shaded surfaces by altering the surface geometry to include small-scale surface relief, which would also generate high-frequency image structure. We report the surprising result here that this manipulation fails to eliminate the perception of blur; the fine texture fails to perceptually 'bind' to the low-frequency image structure when there is a sufficient gap between the spatial scales of the fine and coarse surface structure. These findings suggest that discontinuous 'gaps' in the spatial scale of textures are a segmentation cue the visual system uses to extract multiple causes of image structure. He visual system must somehow distinguish image properties caused by objects from image artifacts such as optical defocus. The authors show that gaps in spatial scale cause fine image texture to appear detached from coarse texture, which induces illusory percepts of defocus. These results suggest that scale continuity is a general grouping principle needed for texture to appear perceptually coherent. [ABSTRACT FROM AUTHOR]

This study examined the effects of commonly used oxidants in sedimentary macroscopic charcoal analysis on two sediment cores from Thirlmere Lakes National Park, Southeast Australia. The cores, from Lake Werri Berri (WB3) and Lake Couridjah (LC2), span ~900 years and 135,000 years, respectively. The Charcoal Accumulation Rate (CHAR) for both charcoal area and count was quantified using four different chemical treatments and compared to a control using only water. We also quantified the Charring Intensity (CI) of isolated charcoal fragments, a proxy for the severity/intensity of fire, determined using the FTIR spectral characteristics of the remaining charcoal after each treatment. We found significant differences in both the area and number of particles across all treatments in both cores. Significantly, we found substantial differences in CI between treatments, with few charcoal particles formed in low-severity fire (e.g., below ~400 °C or 3.0 °C.s.106) in groups treated with an oxidant. In contrast, the control group displayed a wider range of CI values and contained lightly pyrolyzed particles. This suggests that methods using an oxidant to concentrate sedimentary charcoal are potentially biasing records towards high-intensity or -severity fires. We suggest that consideration should be used when choosing laboratory methods based on the hypotheses being tested. [ABSTRACT FROM AUTHOR]

Assessed academic locus of control, self-esteem, and geographical distance from home (actual and perceived) as predictors of college adjustment in 88 female college freshmen. An internal academic locus of control, a high level of self-esteem, and a perception that the distance from home was "just right" were related to four dimensions of college adjustment. (Author/LLL)

This study investigated the effects a dilute solution of bleach (4% sodium hypochlorite), has on charcoal. We were particularly interested in considering if charcoal formed under different conditions of pyrolysis was differentially affected by this treatment, which is commonly used for the quantification of charcoal in sediments. We first produced a series of charcoal samples, under laboratory conditions (at temperatures between 250°C and 800°C and under oxygen limited conditions) and then measured total surface area of charcoal before and after treatment in a solution of 4% bleach. We found that charcoal formed ⩽400°C showed nearly complete bleaching after 24 h, while high temperature charcoal (>400°C) was much more resistant. These results indicate this treatment bleaches charcoal formed at lower temperatures: this means particles charred at low temperature may not be quantified in common optical counting or image analysis methods. This could have serious ramifications for sediment-based paleofire research as low intensity fire may be lost from a record, and the resulting fire history biased towards high intensity (high temperature) fires. Our findings suggest the need for a new, non-destructive method for extracting charcoal from sediment. [ABSTRACT FROM AUTHOR]

Visual deficits in children that result from brain injury, including cerebral/cortical visual impairment (CVI), are difficult to assess through conventional methods due to their frequent co-occurrence with cognitive and communicative disabilities. Such impairments hence often go undiagnosed or are only determined through subjective evaluations of gaze-based reactions to different forms, colors, and movements, which limits any potential for remediation. Here, we describe a novel approach to grading visual health based on eye movements and evidence from gaze-based tracking behaviors. Our approach—the "Visual Ladder"—reduces reliance on the user's ability to attend and communicate. The Visual Ladder produces metrics that quantify spontaneous saccades and pursuits, assess visual field responsiveness, and grade spatial visual function from tracking responses to moving stimuli. We used the Ladder to assess fourteen hospitalized children aged 3 to 18 years with a diverse range of visual impairments and causes of brain injury. Four children were excluded from analysis due to incompatibility with the eye tracker (e.g., due to severe strabismus). The remaining ten children—including five non-verbal children—were tested multiple times over periods ranging from 2 weeks to 9 months, and all produced interpretable outcomes on at least three of the five visual tasks. The results suggest that our assessment tasks are viable in non-communicative children, provided their eyes can be tracked, and hence are promising tools for use in a larger clinical study. We highlight and discuss informative outcomes exhibited by each child, including directional biases in eye movements, pathological nystagmus, visual field asymmetries, and contrast sensitivity deficits. Our findings indicate that these methodologies will enable the rapid, objective classification and grading of visual impairments in children with CVI, including non-verbal children who are currently precluded from most vision assessments. This would provide a much-needed differential diagnostic and prognostic tool for CVI and other impairments of the visual system, both ocular and cerebral. [ABSTRACT FROM AUTHOR]

Introduction: Traumatic Brain Injury (TBI) is a prevalent health issue in the US and even more prevalent amongst members of the armed forces. The purpose of this project was to evaluate the association between history of TBI and rates of dental treatment performed, endodontic therapy, and high caries risk. Methods: This was a retrospective medical and dental records study. The first 100 of a chosen dental hygienist's patients in 2016 who were seen for dental prophylaxis appointments were chosen as subjects. Armed Forces Health Longitudinal Technology Application (AHLTA) and Corporate Dental System (CDS) records were used to gather information on these subjects including rank, age, gender, duty status, tobacco use, history of TBI, total number of dental procedures, total Dental Weighted Value (DWV), number of endodontic procedures, endodontic DWV, high caries risk categorization, total days dental fitness class 1, and total days dental fitness class 3. From these subjects, a "TBI group" and a "Non-TBI group" were formed. T-Test analyses were performed to compare these groups to each other in categories of total number of dental procedures, total DWV, total days dental fitness class 1, and total days class 3. Relative risks ratio analysis was used to compare these groups in terms of high caries risk categorization. Results: Eight out of 100 subjects had a history of TBI. All TBI events were mild. Six subjects had 1 event, 1 had 2 events, and 1 had 4 events. The TBI group had a statistically higher mean number of dental procedures (P=0.00000025) and mean total DWV (P=0.0000062) compared to the non-TBI group. No subjects from the TBI group had an endodontic procedure. The TBI group had lower mean days in dental fitness class 1 and more mean days in dental fitness class 3, but the results were not statistically significant. The TBI group had lower high caries risk categorization rates than the non-TBI group, but the results were not statistically significant. Conclusions: Patients with a history of TBI had a significantly higher number of dental procedures performed and DWV generated compared to patients without a history of TBI. [ABSTRACT FROM AUTHOR]

Objectives: Plantar heel pain (PHP) is the most common cause of heel pain and can be debilitating; 20% of patients are refractory to standard of care. The Fascial Distortion Model (FDM), a novel manual diagnostic and treatment strategy, is purported to be effective for chronic pain; however, no rigorous studies document its effectiveness. We assessed the FDM for care of PHP. Design: Single arm prospective effectiveness study. Settings/Location: Outpatient primary care clinic; Fort Gordon, GA. Subjects: Outpatient adults. Interventions: Participants received an FDM-informed diagnostic and treatment strategy to identify fascial "distortions" at the foot based on patient-reported pain patterns and palpatory examination and then to provide distortion-specific manual therapy at baseline and 1 week. Outcome Measures: Primary outcome measure (0, 1, and 16 weeks): the Foot Pain subscale on the validated Foot Health Status Questionnaire (FHSQ; 0–100 points on each of eight separate subscales); secondary outcome measures (0, 1, and 16 weeks): the seven remaining subscales on the FHSQ, visual analog pain scale (VAS, 0–100 points), and plantar fascia thickness of the most effected foot assessed by ultrasound (0 and 16 weeks). Analysis was performed per protocol using repeated-measures analysis of variance. Results: One hundred and ninety-seven participants were screened; 33 were enrolled. Twenty-eight participants received two FDM procedures. Compared with baseline, improvement on the FHSQ Foot Pain (33.8–23.6 points) and Foot Function (23.9–19.8 points) subscales and VAS (44.7–27.7 points) at 16 weeks was statistically significant (all p's < 0.001) and clinically important representing large effect sizes. Relative to baseline, 16-week ultrasound demonstrated reduced average plantar fascia thickness (0.6–0.9 mm [p = 0.001]). Demographic characteristics were unrelated to response. Satisfaction was high. There were no serious adverse events; side effects included consistent mild-to-moderate self-limited pain. Conclusions: Participants with PHP who received FDM-informed care reported significant and sustained improvement on validated foot pain and foot function measures; additional findings included decreased plantar fascial thickness. These results require corroboration in a larger randomized controlled study. Clinical Trial Registration No: DDEAMC17005. [ABSTRACT FROM AUTHOR]

A compliance-based excavation on Parramatta River (western Sydney) found evidence of a brief visitation by Aboriginal people during the terminal Pleistocene (c.14 ka), from which an exotic raw material–medium-grained porphyroblastic andalusite-cordierite hornfels–was recovered. This raw material is rare in the region, only found in the Megalong Valley situated some 75 km west of the site in Parramatta, and separated from the site by the Blue Mountains–a 40 km wide, 1 km high dissected sandstone upland. Historical observations and geological evidence suggest that the Coxs River, which runs through the upland, formed the probable connection between the two locales. The formation of the site at c.14 ka, along with our broader understanding of the region, suggests that the upland was only explored after the Last Glacial Maximum (LGM) and that the Great Dividing Range may have formed a significant barrier to early peopling of Sahul. Further, a delay between the end of the LGM and the exploration of the region implies populations were severely affected by the event and required considerable time to recover. The coincident timing of rapid sea-level rise from Meltwater Phase Pulse 1A and an increased supply of moisture associated with the Antarctic Climate Reversal at the time of many site initiations may have been factors in the upland and south west slopes visitation. Finally, the movement of the unusual hornfels artefact provides a coarse indication of the ranging territory for hunter-gatherers living in a temperate region (c. 8,000 km2) at this time. This is probably a lower estimate but begins to provide a quantitative value with which to begin to ratify the increasing divergence between archaeological and genomic studies in their definitions of mobility, sedentism and regional nomadism. [ABSTRACT FROM AUTHOR]

In Australia, the drivers of precolonial fire regimes remain contentious, with some advocating an anthropogenic-dominated regime, and others highlighting the importance of climate, climatic variability or alternatively some nexus between climate and human activity. Here, we explore the inter-relationships between fire, humans and vegetation using macroscopic charcoal, archaeology and palynology over the last ~5430 cal. year BP from Broughton Island, a small, near-shore island located in eastern Australia. We find a clear link between fire and the reduction of arboreal pollen and rainforest indicators on the island, especially at ~4.0 ka and in the last ~1000 years. Similarities with comparable palaeoenvironmental records of fire in the region and a record of strong El Niño (dry, fire-prone) events supports the contention that climate was a significant influence on the fire regimes of Broughton Island. However, two periods of enhanced fire activity, at ~4000 years BP and ~<600 years BP have weaker links to climate, and perhaps reflect anthropogenic activity. Changes to the fire regime in the last ~600 years corresponds with the earliest evidence of Indigenous archaeology on the island, and coincides with implications that Polynesian people were present in the region. After the mid-Twentieth Century a human-dominated fire regime is also an obvious feature of the reconstructed fire record on Broughton Island. [ABSTRACT FROM AUTHOR]

Fire interactions and their relation with climate in Australia were evaluated using paleorecords. The records studied show that fires or burning was facilitated during periods of climate change.

Aim: Determine the extent to which remote, high‐altitude (Afroalpine) aquatic ecosystems in tropical Africa have been impacted by global and regional‐scale environmental change processes. Location: Two volcanic crater lakes (Bisoke and Muhavura) in the Afroalpine zone, Albertine (Western) Rift, central Africa. Methods: Sediment cores were collected from Bisoke and Muhavura lakes and dated using radiometric techniques. A range of sediment‐based proxies was extracted from the cores and quantified. Sedimentary data were subjected to statistical analyses that contributed to the identification of influential environmental variables and their effects on diatom assemblages, the determination of variations in spatial beta diversity and estimates of the rate of compositional turnover over the last c. 1,200 years. Results: Sediments from the two sites provide evidence of the sensitivity of remote, Afroalpine aquatic ecosystems to perturbation. Climate variability has been a major driver of ecological change, particularly at Bisoke Lake, throughout the c. 1,200‐year‐long record, while Muhavura Lake has been directly impacted by and recovered from at least one volcanic eruption during this time. The effects of climatic warming from the mid‐ to late 19th century and especially from the late 20th century, possibly accentuated by atmospheric deposition‐driven nutrient enrichment, appear increasingly in lockstep. Effects include changes in diatom community composition, increased productivity and compositional turnover, and biotic homogenization (reduced spatial beta diversity) between the two sites. Main conclusions: The two Afroalpine sites record changes in atmospheric conditions and their effects on diatom assemblage composition, particularly over the last c. 150 years. Drivers of these changes have the potential to disrupt ecosystems at lower altitudes in the Albertine Rift, including biodiverse areas of forest, and across tropical Africa more widely. [ABSTRACT FROM AUTHOR]

Highlights • Shady is a new open-source cross-platform visual stimulus toolbox for Python. • A compiled engine overcomes Python's deficiencies regarding timing precision. • Effective dynamic range is enhanced automatically via noisy-bit dithering. • Powerful programming tools allow easy real-time stimulus animation—even interactively. • Shady performs well under challenging conditions (sub-optimal systems; multi-tasking). Abstract Background Precise definition, rendering and manipulation of visual stimuli are essential in neuroscience. Rather than implementing these tasks from scratch, scientists benefit greatly from using reusable software routines from freely available toolboxes. Existing toolboxes work well when the operating system and hardware are painstakingly optimized, but may be less suited to applications that require multi-tasking (for example, closed-loop systems that involve real-time acquisition and processing of signals). New method We introduce a new cross-platform visual stimulus toolbox called Shady (https://pypi.org/project/Shady)—so called because of its heavy reliance on a shader program to perform parallel pixel processing on a computer's graphics processor. It was designed with an emphasis on performance robustness in multi-tasking applications under unforgiving conditions. For optimal timing performance, the CPU drawing management commands are carried out by a compiled binary engine. For configuring stimuli and controlling their changes over time, Shady provides a programmer's interface in Python, a powerful, accessible and widely-used high-level programming language. Results Our timing benchmark results illustrate that Shady's hybrid compiled/interpreted architecture requires less time to complete drawing operations, exhibits smaller variability in frame-to-frame timing, and hence drops fewer frames, than pure-Python solutions under matched conditions of resource contention. This performance gain comes despite an expansion of functionality (e.g. "noisy-bit" dithering as standard on all pixels and all frames, to enhance effective dynamic range) relative to previous offerings. Conclusions Shady simultaneously advances the functionality and performance available to scientists for rendering visual stimuli and manipulating them in real time. [ABSTRACT FROM AUTHOR]

Radiocarbon (14C) dating is widely used to determine the age of organic material in palaeoenvironmental research. Here we compare 14C dates (n=17) resulting from macro-charcoal (>250 μm), short-lived plant macrofossils and pollen-rich residues isolated from two mire environments in eastern Australia. In most samples we found that short-lived plant macrofossils were the youngest organic component, the charcoal samples most often fell into the middle and the pollen-rich residues consistently returned older dates than the other samples. Although pollen-rich residues have been widely used for 14C dating in Australasia we suggest some caution in their use, perhaps because in our fire-prone environments these samples often also contain fine charcoal and other oxidative resistant organic matter that is older than the surrounding sediment matrix. The macro-charcoal samples also often returned older calibrated ages compared to short-lived plant macrofossils from the same depth, although this difference was relatively small (<245 years). Our results demonstrate that 14C dating of short-lived plant macrofossils are likely to yield more accurate chronologies and we advocate their routine use in palaeoenvironmental research when they are available. [ABSTRACT FROM AUTHOR]

Introduction: Military Service Members (SMs) with post-concussive symptoms are commonly referred for further evaluation and possible treatment to Department of Defense Traumatic Brain Injury Clinics where neuropsychological screening/evaluations are being conducted. Understudied to date, the base rates of noncredible task engagement/performance validity testing (PVT) during cognitive screening/evaluations in military settings appears to be high. The current study objectives are to: (1) examine the base rates of noncredible PVTs of SMs undergoing routine clinical or Medical Evaluation Board (MEB) related workups using multiple objective performance-based indicators; (2) determine whether involvement in MEB is associated with PVT or symptom exaggeration/symptom validity testing (SVT) results; (3) elucidate which psychiatric symptoms are associated with noncredible PVT performances; and (4) determine whether MEB participation moderates the relationship between psychological symptom exaggeration and whether or not SM goes on to demonstrate PVTs failures - or vice versa.Materials and Methods: Retrospective study of 71 consecutive military concussion cases drawn from a DoD TBI Clinic neuropsychology clinic database. As part of neuropsychological evaluations, patients completed several objective performance-based PVTs and SVT.Results: Mean (SD) age of SMs was 36.0 (9.5), ranging from 19-59, and 93% of the sample was male. The self-identified ethnicity resulted in the following percentages: 62% Non-Hispanic White, 22.5% African American, and 15.5% Hispanic or Latino. The majority of the sample (97%) was Active Duty Army and 51% were involved in the MEB at the time of evaluation. About one-third (35.9%) of routine clinical patients demonstrated failure on one or more PVT indicators (12.8% failed 2) while PVT failure rates amongst MEB patients ranged from 15.6% to 37.5% (i.e., failed 2 or 1 PVTs, respectively). Base rates of failures on one or more PVT did not differ between routine clinical versus MEB patients (p = 0.94). MEB involvement was not associated with increased emotional symptom response bias as compared to routine clinical patients. PVT failures were positively correlated with somatization, anxiety, depressive symptoms, suspicious and hostility, atypical perceptions/alienation/subjective cognitive difficulties, borderline personality traits/features, and penchant for aggression in addition to symptom over-endorsement/exaggeration. No differences between routine clinical and MEB patients across other SVT indicators were found. MEB status did not moderate the relationship between any of the SVTs.Conclusion: Study results are broadly consistent with the prior published studies that documented low to moderately high base rates of noncredible task engagement during neuropsychological evaluations in military and veteran settings. Results are in contrast to prior studies that have suggested involvement in MEB is associated with increased likelihood of poor PVT performances. This is the first to show that MEB involvement did not enhance/strengthen the association between PVT performances and evidence of SVTs. Consistent with prior studies, these results do highlight that the same SMs who fail PVTs also tend to be the ones who go on to endorse a myriad of psychiatric symptoms and proclivities. Implications of variable or poor task engagement during routine clinical and MEB neuropsychological evaluation in military settings on treatment and disposition planning cannot be overstated. [ABSTRACT FROM AUTHOR]

The Amundsen Sea Low (ASL) plays a major role in the climate and environment of Antarctica and the Southern Ocean, including surface air temperature and sea ice concentration changes. Unfortunately, a relative dearth of observational data across the Amundsen and Bellingshausen seas prior to the satellite era (post-1979) limits our understanding of the past behaviour and impact of the ASL. The limited proxy evidence for changes in the ASL are primarily restricted to the Antarctic where ice core evidence suggests a deepening of the atmospheric pressure system during the late Holocene. However, no data have previously been reported from the northern side of the ASL. Here we report a high-resolution, multi-proxy study of a 5000-year-long peat record from the Falkland Islands, a location sensitive to contemporary ASL dynamics which modulates northerly and westerly airflow across the southwestern South Atlantic sector of the Southern Ocean. In combination with climate reanalysis, we find a marked period of wetter, colder conditions most likely the result of enhanced southerly airflow between 5000 and 2500 years ago, suggesting limited ASL influence over the region. After 2500 years ago, drier and warmer conditions were established, implying more westerly airflow and the increased projection of the ASL onto the South Atlantic. The possible role of the equatorial Pacific via atmospheric teleconnections in driving this change is discussed. Our results are in agreement with Antarctic ice core records and fjord sediments from the southern South American coast, and suggest that the Falkland Islands provide a valuable location for reconstructing high southern latitude atmospheric circulation changes on multi-decadal to millennial timescales. [ABSTRACT FROM AUTHOR]