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A numerical model is used to investigate the resonances of the Gulf of Carpentaria and the Arafura Sea. The model is forced at the shelf edge, first with physically realistic real values of angular velocity. The response functions at points within the region show maxima and other behaviour which imply that resonances are involved but it is difficult to be more specific. The study is then extended to complex angular velocities and the results then show a clear pattern of gravity wave and Rossby wave like resonances. The properties of the resonances are investigated and used to reinterpret the responses at real values of angular velocity. It is found that in some regions the response is dominated by modes trapped between the shelf edge and the coast or between opposing coastlines. In other regions the resonances show cooperative behaviour, possibly indicating the importance of other physical processes. [ABSTRACT FROM AUTHOR]

Digital inclusion research explores the complex inequalities among different societal groups that affect people's ability to fully participate in social, economic, and cultural life. Globally, digital inequalities exist between Indigenous and non-Indigenous people and this paper contributes to a growing body of literature focused on Indigenous digital inclusion in Australia. This paper outlines how a team of Indigenous and non-Indigenous researchers developed an Indigenous research methodology to investigate the digital inclusion challenges, and opportunities, for Aboriginal families living in a remote community on Mornington Island in the Gulf of Carpentaria. This methodology applies principles of decolonisation, through Indigenous yarning and photography, to foreground the voices of Indigenous people in articulating barriers and solutions to low levels of digital inclusion in their community. The findings detail the everyday and novel ways Indigenous families use the internet and digital devices, and how these insights might inform Indigenous-focused policy, practices and programs. [ABSTRACT FROM AUTHOR]

The diurnal cycle of precipitation and its associated land‐sea breeze circulation over coastal northern Australia are investigated using surface wind speed and enthalpy (latent and sensible heat) fluxes from the Cyclone Global Navigation Satellite System. Composite results during the austral summer of 2018–2022 show that diurnal precipitation propagates westward from the Cape York Peninsula into the Gulf of Carpentaria. The diurnal cycle of precipitation and surface wind speed are strongly coupled, with the wind speed maximum slightly leading the precipitation maximum. Additionally, analysis of the moist static energy budget shows that surface fluxes help support the westward‐propagation of diurnal precipitation. These results—based on novel satellite data and reanalysis—are consistent with previous studies that have examined the impact of the land‐sea breeze on the diurnal cycle of precipitation. The results provide a benchmark for model representation of this important atmosphere‐ocean‐land interaction. Plain Language Summary: The modulation of the diurnal cycle of precipitation over coastal northern Australia by surface winds was studied using the recently launched NASA Cyclone Global Navigation Satellite System (CYGNSS). Results show a strong connection between the daily cycles of precipitation and surface wind speed, with an offshore wind speed maximum leading the precipitation maximum by a few hours. Westward propagation of diurnal precipitation and wind speed signals occurs from the Cape York Peninsula into the Gulf of Carpentaria. A thermodynamic analysis supports the importance of the wind speed signal and associated surface fluxes for fostering offshore precipitation propagation. The novelty of this paper lies in the use of the new CYGNSS retrievals, which provide better space and time coverage of surface wind speed than previous satellite‐based measurements and are not as negatively affected by precipitation contamination. Key Points: Cyclone Global Navigation Satellite System wind speeds and latent heat fluxes are used to study the diurnal cycle over the northern Australia coastal regionEnhanced diurnal precipitation is associated with enhanced surface wind speed and convergenceDiurnal precipitation and surface wind speed signals propagate westward in tandem from the Cape York Peninsula [ABSTRACT FROM AUTHOR]

This paper introduces Xanthomelon amurndamilumila sp. nov. , a newly-discovered land snail species inhabiting the North East Isles, offshore from Groote Eylandt (= Ayangkidarrba), north-western Gulf of Carpentaria, in the Northern Territory, Australia. Specimens of this species were first collected during the 2021 Bush Blitz expedition to Groote Eylandt, a large offshore archipelago previously unexplored for land snails. The taxonomic status of the new species was established through a comprehensive analysis of comparative morphology and mitochondrial genetics: X. amurndamilumila forms a maximally supported clade closely related to X. arnhemense and is characterised by a unique combination of morphological characteristics, including smaller shell size, distinctive sculpture of collabral ridges and specific features of its reproductive anatomy. The genetic divergence and phylogenetic relationships suggest historical isolation. While the discovery of X. amurndamilumila sp. nov. enriches our understanding of land snail diversity in the Northern Territory, its conservation status is of concern on North East Island because of habitat degradation caused by feral deer. [ABSTRACT FROM AUTHOR]

Rather than passively accepting development, some Indigenous communities have forced their demands into corporate decision-making. Accordingly, recognising and responding to community expectations becomes a matter of prudent strategy and 'enlightened self-interest'. This paper examines the case of Century Zinc Mine in Queensland's Gulf of Carpentaria where the miner undertook negotiations and reached agreement with local Indigenous communities. It was later held to account by communities concerned about insufficient implementation of this agreement. Discussion then explores the campaign against Jabiluka uranium mine in Australia's Northern Territory, especially why multinational miner Rio Tinto deferred to local community wishes surrounding development. These experiences show that Indigenous communities are most effective in bringing leverage over mining companies when they impact upon profit or future profit (often related to reputation with specific audiences). The parameters and consequent limitations of a company's responsiveness to community demands reinforce fundamental roles for the state as ultimate regulator and provider. [ABSTRACT FROM AUTHOR]

Ghost gear - abandoned, lost, or otherwise discarded fishing gear - has been recognised as a global environmental challenge since the mid-1980s, and yet little social science attention has fallen on the phenomenon. This paper explores how the burden of global fisheries, materialised through its gear, is experienced and managed. How is ghost gear encountered? How is it understood? What influence does it have, and what responses does it provoke? To consider these questions, the paper begins with detailing of an encounter with ghost gear and Aboriginal rangers on the eastern coast of the Gulf of Carpentaria, northern Australia. Understanding encounters as tangles of interlaced threads, rather than isolated intimacies, the paper also follows ghost gear beyond the experience of beach clean-up. How ghost gear journeys to this beach, and the mobilities and meetings that occur during its travels is explored, as well as the policy responses to ghost gear that figure it primarily as marine debris to be managed through territorial control as isolated 'waste'. These more-than-human stories offer insights into the distributed agencies, complex relations, and differential responsibilities involved in the phenomenon of ghost gear, and efforts to deal with it as part of land-sea assemblies. [ABSTRACT FROM AUTHOR]

The Investigator Tree, so named after Matthew Flinders' ship HMS Investigator, is an inscribed tree currently on display in the Queensland Museum. Before being accessioned into the Queensland Museum's collection in 1889, the Investigator Tree grew on the western shore of Sweers Island in the southern Gulf of Carpentaria. The tree's "Investigator" inscription, attributed to Flinders (1802), provided the catalyst for future and varied forms of European inscription making on Sweers Island, including a contentious additional "Investigator" inscription on the Investigator Tree carved by Thomas Baines in 1856. Previous researchers have speculated that Baines' second "Investigator" inscription has caused the faded original "Investigator" inscription to be misinterpreted as either a Chinese or Dutch inscription predating Flinders' visit to Sweers Island. For the first time, this study undertakes a physical examination of all markings on the Investigator Tree, including a second portion of the tree located at the Queensland Museum since 2009. In combination with a review of the archival and historical record, findings provide alternative interpretations regarding the (28) inscriptions to address outstanding questions. Archival documents demonstrate that there were at least three inscribed trees on Sweers Island. This paper also revisits the possibility of there once being pre-Flinders inscriptions on the Investigator Tree. [ABSTRACT FROM AUTHOR]

In 1859 the Dutch historian, L.C.D. van Dijk published a book on the voyages of discovery made by Jan Carstenszoon in 1623 and Jean Etienne Gonzal in 1756 to the Gulf of Carpentaria. The book contains a commentary of the two voyages as well as a copy of Carstenszoon's journal. It also contains a curious map that not only renames the Gulf of Carpentaria and the west coast of Cape York Peninsula, but also questions the naming of Arnhem Land and some of its named locations. This paper examines some of the possible reasoning behind this unusual map. [ABSTRACT FROM AUTHOR]

Copyright of Archaeology in Oceania is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Internal solitary waves frequently occur in the atmosphere. On rare occasions, they create the awe-inspiring spectacle known, for example, as the Morning Glory Clouds, a spectacular roll cloud, or series of roll clouds predictably appearing in the southern part of the Gulf of Carpentaria. Nevertheless, solitary wave–wave interactions have rarely been studied and documented; thus, we here focus on the long-time evolution of the superposition of two solitons featuring an X-shape and, more complicated, the interactions between three solitons initially posing as a Y-shape. To better understand the underlying dynamics of these phenomena, we derive a bidirectional and isotropic theoretical equation in a two-layer fluid system with variable bottom topography. This is accomplished by using its Hamiltonian structure and the Taylor expansion of the Dirichlet–Neumann operator for the potential theory. Essentially, the derived equation is an extension of the widely recognized Benjamin–Ono equation at two horizontal dimensions, and thereby, it possesses plane soliton solutions propagating in any horizontal direction. It is noted that the initial angles play an essential role in the oblique wave–wave interactions, manifested as the determination of waveforms, amplitudes, and the emergence of the Mach stem. In addition, the wave evolution is slightly modulated by the topographic effects, partly due to invoking the assumption of small topography. [ABSTRACT FROM AUTHOR]

In coastal areas of the globe, open shell matrix sites are commonly used to establish regional chronologies of human occupation and identify patterns of cultural change, particularly for the Holocene, post-sea-level stabilisation period. Despite this, many basic sedimentary analyses that are routinely applied to rockshelter deposits (e.g. geophysical characterisation, particle size etc) are rarely applied to these sites. Magnetic susceptibility, occasionally used in rockshelters, has never been used to investigate shell matrix sites in Australia, despite several international studies identifying its efficacy for other types of open sites. This paper reports a pilot project applying a range of conventional sedimentary and archaeological analyses, as well as magnetic susceptibility at three anthropogenic shell mounds on Mornington Island, Gulf of Carpentaria, Australia. Results are compared to, firstly, assess site integrity and, secondly, to ascertain whether magnetic signatures are related to cultural or natural site formation processes. The results establish that the mounds were repeatedly visited, despite the archaeological evidence, including radiocarbon ages, suggesting effectively 'instantaneous' deposition. This has important implications for studies of other shell mounds where the limitations of radiocarbon dating precision may also mask multiple deposition events. [ABSTRACT FROM AUTHOR]

Between late 2015 and early 2016, more than 7,000 ha of mangrove forest died along the coastline of the Gulf of Carpentaria, in northern Australia. This massive die-off was preceded by a strong 2015/2016 El Niño event, resulting in lower precipitation, a drop in sea level and higher than average temperatures in northern Australia. In this study, we investigated the role of hydraulic failure in the mortality and recovery of the dominant species, Avicennia marina , 2 years after the mortality event. We measured predawn water potential (Ψpd) and percent loss of stem hydraulic conductivity (PLC) in surviving individuals across a gradient of impact. We also assessed the vulnerability to drought-induced embolism (Ψ50) for the species. Areas with severe canopy dieback had higher native PLC (39%) than minimally impacted areas (6%), suggesting that hydraulic recovery was ongoing. The high resistance of A. marina to water-stress-induced embolism (Ψ50 = −9.6 MPa), indicates that severe water stress (Ψpd < −10 MPa) would have been required to cause mortality in this species. Our data indicate that the natural gradient of water-stress enhanced the impact of El Niño, leading to hydraulic failure and mortality in A. marina growing on severely impacted (SI) zones. It is likely that lowered sea levels and less frequent inundation by seawater, combined with lower inputs of fresh water, high evaporative demand and high temperatures, led to the development of hyper-salinity and extreme water stress during the 2015/16 summer. [ABSTRACT FROM AUTHOR]

In this study, we introduce a localized definition of the onset and retreat of the northern Australian rainy season that is solely based on gridded rainfall analysis. Our analysis shows that the local onset/retreat of the rainy season has considerable spatial heterogeneity. Onset is earlier and the length of the rainy season is longer to the west of the Gulf of Carpentaria than to its east. Furthermore, we also find the local onset/retreat is influenced by the wet and dry spells of the 30–60-day intraseasonal oscillation. Much of the retreat of the rainy season occurs in the dry phases of the intraseasonal oscillation. However, intriguingly, a majority of the local onset of the rainy season occurs during dry phases of the intraseasonal oscillation. The ENSO teleconnection with the variable-length northern Australian rainy season also exhibits spatial heterogeneity and significant differences from rainfall anomalies using the fixed-length boreal winter season. The onset, the retreat, the length, and the seasonal rainfall anomalies of the rainy season display a stronger correlation with the ENSO SST anomalies for the region east of 140°E relative to its west. The strong covariability of the local onset date with the corresponding seasonal length and seasonal rainfall anomalies over northern Australia offers the advantage of monitoring the onset of the northern Australian rainy season to provide an outlook for the forthcoming season. The proposed local definition of onset/retreat of the northern Australian rainy season is simple, objective, and unambiguous and is ideally suited for real-time monitoring of the evolution of the season. [ABSTRACT FROM AUTHOR]

Freshwater is a critical input to estuaries but is under increasing demand to support upstream human activities. In this study, otolith biochronology was used to quantify the relationship between river discharge and juvenile growth rates of barramundi (Lates calcarifer) in three regions of the Gulf of Carpentaria in northern Australia. In all regions, river discharge had a strong positive effect on juvenile growth rates. Models were also developed which incorporated the Southern Oscillation Index (SOI) and the Madden–Julian Oscillation (MJO). SOI values corresponding to La Niña events had strong positive consequences for juvenile barramundi growth rates in all regions, and the intensity of positive wet season MJO pulses had a strong positive effect on growth rates in the perennially flowing river, but not the intermittently flowing rivers. The consequences of three hypothetical water development scenarios were estimated for the perennial river. The model predicted a 12%, 8% and 1% reduction in annual barramundi growth rates under proposed scenarios for 18%, 8%, and 3% reduction in river discharge, respectively. Fish growth is a robust, quantitative metric that can be monitored pre and post water resource development to identify the least impactful development scenario and monitor its compliance and success through time. [ABSTRACT FROM AUTHOR]

During the strong El Niño event of 2015–2016 large‐scale dieback of mangrove forests was observed in the Gulf of Carpentaria region of northern Australia. These and other intertidal communities are also extensive along the 7,400 km coastline of north‐eastern Australia. Determination of their floristic composition, potential carbon (C) store and sequestration capacity, and vulnerability to climate extremes is required for their effective conservation management and was the aim of this study.Standardized, state‐wide quantitative classification methods identified five mangrove forest and three saltmarsh communities covering 2,604 km2 along this coastline.Estuarine and oceanic mangrove forests were mapped separately. Carbon storage and sequestration capacity of the intertidal communities and their vulnerability to strong El Niño events were estimated using published data and GIS analyses.An estimated potential 126.2 (± 27.3 SEM) Tg C and 8.3 (±0.4 SD) Tg C were stored in the mangrove forests and saltmarshes, respectively. Comparatively, the rainforests of the region stored an estimated equivalent amount of C but covered three times the area, and the most widespread woodlands (Eucalyptus tetrodonta) of the region stored an estimated 1.5 times the C but covered 16 times the area. The C stored in the intertidal communities was estimated as equivalent to 493.47 Tg of CO2, valued at AU$6.8 billion on the Australian carbon market in December 2018. Annual C sequestration potential was 0.18–0.34 Tg C/year, valued between AU$8.9 and $17 million.Approximately 360 ha of mangrove forest was estimated as lost because of dieback during the 2015–16 El Niño event. Three types of mangrove forest were identified as potentially vulnerable to dieback from El Niño‐driven climate events.This study highlights the national and global significance of these intertidal systems and our findings need to be incorporated in future conservation and development planning of northern Australia. [ABSTRACT FROM AUTHOR]

A combination of elemental analysis, bulk stable isotope analysis (bulk SIA) and compound-specific stable isotope analysis of amino acids (CSIA-AA) was used to assess and monitor carbon (C), nitrogen (N) and sulfur (S) cycling of a mangrove ecosystem that suffered mass dieback of trees in the Gulf of Carpentaria, Australia in 2015–2016, attributed to an extreme drought event. Three field campaigns were conducted 8, 20 and 32 months after the event over a period from 2016 to 2018 to obtain biological time-series data. Invertebrates and associated organic matter including mangroves and sediments from the impacted ecosystem showed enrichment in 13 C, 15 N and 34 S relative to those from an adjacent unimpacted reference ecosystem, likely indicating lower mangrove carbon fixation, lower nitrogen fixation and lower sulfate reduction in the impacted ecosystem. For example, invertebrates representing the feeding types of grazing, leaf feeding and algae feeding were more 13 C enriched at the impacted site, by 1.7 ‰–4.1 ‰, and these differences did not change over the period from 2016 to 2018. The CSIA-AA data indicated widespread 13 C enrichment across five essential amino acids and all groups sampled (except filter feeders) within the impacted site. The seedling density increased from 0.2 m -2 in 2016 to 7.1 m -2 in 2018 in the impacted forest, suggesting recovery of the vegetation. Recovery of CNS cycling, however, was not evident even after 32 months, suggesting a biogeochemical legacy of the mortality event. Continued monitoring of the post-dieback forest is required to predict the long-term trajectory of ecosystem recovery. This study shows that time-series SIA can track biogeochemical changes over time and evaluate recovery of an impacted ecosystem from an extreme event. [ABSTRACT FROM AUTHOR]

With recent advances in sequencing technology, genomic data are changing how important conservation management decisions are made. Applications such as Close‐Kin Mark‐Recapture demand large amounts of data to estimate population size and structure, and their full potential can only be realised through ongoing improvements in genotyping strategies. Here we introduce DArTcap, a cost‐efficient method that combines DArTseq and sequence capture, and illustrate its use in a high resolution population analysis of Glyphis garricki, a rare, poorly known and threatened euryhaline shark. Clustering analyses and spatial distribution of kin pairs from four different regions across northern Australia and one in Papua New Guinea, representing its entire known range, revealed that each region hosts at least one distinct population. Further structuring is likely within Van Diemen Gulf, the region that included the most rivers sampled, suggesting additional population structuring would be found if other rivers were sampled. Coalescent analyses and spatially explicit modelling suggest that G. garricki experienced a recent range expansion during the opening of the Gulf of Carpentaria following the conclusion of the Last Glacial Maximum. The low migration rates between neighbouring populations of a species that is found only in restricted coastal and riverine habitats show the importance of managing each population separately, including careful monitoring of local and remote anthropogenic activities that may affect their environments. Overall we demonstrated how a carefully chosen SNP panel combined with DArTcap can provide highly accurate kinship inference and also support population structure and historical demography analyses, therefore maximising cost‐effectiveness. [ABSTRACT FROM AUTHOR]

A massive mangrove dieback event occurred in 2015–2016 along ∼1000km of pristine coastline in the Gulf of Carpentaria, Australia. Here, we use sediment and wood chronologies to gain insights into geochemical and climatic changes related to this dieback. The unique combination of low rainfall and low sea level observed during the dieback event had been unprecedented in the preceding 3 decades. A combination of iron (Fe) chronologies in wood and sediment, wood density and estimates of mangrove water use efficiency all imply lower water availability within the dead mangrove forest. Wood and sediment chronologies suggest a rapid, large mobilization of sedimentary Fe , which is consistent with redox transitions promoted by changes in soil moisture content. Elemental analysis of wood cross sections revealed a 30- to 90-fold increase in Fe concentrations in dead mangroves just prior to their mortality. Mangrove wood uptake of Fe during the dieback is consistent with large apparent losses of Fe from sediments, which potentially caused an outwelling of Fe to the ocean. Although Fe toxicity may also have played a role in the dieback, this possibility requires further study. We suggest that differences in wood and sedimentary Fe between living and dead forest areas reflect sediment redox transitions that are, in turn, associated with regional variability in groundwater flows. Overall, our observations provide multiple lines of evidence that the forest dieback was driven by low water availability coinciding with a strong El Niño–Southern Oscillation (ENSO) event and was associated with climate change. [ABSTRACT FROM AUTHOR]

Summary: Growing evidence indicates that tree‐stem methane (CH4) emissions may be an important and unaccounted‐for component of local, regional and global carbon (C) budgets. Studies to date have focused on upland and freshwater swamp‐forests; however, no data on tree‐stem fluxes from estuarine species currently exist.Here we provide the first‐ever mangrove tree‐stem CH4 flux measurements from  >50 trees (n = 230 measurements), in both standing dead and living forest, from a region suffering a recent large‐scale climate‐driven dieback event (Gulf of Carpentaria, Australia).Average CH4 emissions from standing dead mangrove tree‐stems was 249.2 ± 41.0 μmol m−2 d−1 and was eight‐fold higher than from living mangrove tree‐stems (37.5 ± 5.8 μmol m−2 d−1). The average CH4 flux from tree‐stem bases (c. 10 cm aboveground) was 1071.1 ± 210.4 and 96.8 ± 27.7 μmol m−2 d−1 from dead and living stands respectively. Sediment CH4 fluxes and redox potentials did not differ significantly between living and dead stands. Our results suggest both dead and living tree‐stems act as CH4 conduits to the atmosphere, bypassing potential sedimentary oxidation processes.Although large uncertainties exist when upscaling data from small‐scale temporal measurements, we estimated that dead mangrove tree‐stem emissions may account for c. 26% of the net ecosystem CH4 flux. [ABSTRACT FROM AUTHOR]

Projections of sea level rise (SLR) will lead to increasing coastal impacts during extreme sea level events globally; however, there is significant uncertainty around short-term coastal sea level variability and the attendant frequency and severity of extreme sea level events. In this study, we investigate drivers of coastal sea level variability (including extremes) around Australia by means of historical conditions as well as future changes under a high greenhouse gas emissions scenario (RCP 8.5). To do this, a multi-decade hindcast simulation is validated against tide gauge data. The role of tide–surge interaction is assessed and found to have negligible effects on storm surge characteristic heights over most of the coastline. For future projections, 20-year-long simulations are carried out over the time periods 1981–1999 and 2081–2099 using atmospheric forcing from four CMIP5 climate models. Changes in extreme sea levels are apparent, but there are large inter-model differences. On the southern mainland coast all models simulated a southward movement of the subtropical ridge which led to a small reduction in sea level extremes in the hydrodynamic simulations. Sea level changes over the Gulf of Carpentaria in the north are largest and positive during austral summer in two out of the four models. In these models, changes to the northwest monsoon appear to be the cause of the sea level response. These simulations highlight a sensitivity of this semi-enclosed gulf to changes in large-scale dynamics in this region and indicate that further assessment of the potential changes to the northwest monsoon in a larger multi-model ensemble should be investigated, together with the northwest monsoon's effect on extreme sea levels. [ABSTRACT FROM AUTHOR]

An established tidal model, validated for present-day conditions, is used to investigate the effect of large levels of sea-level rise (SLR) on tidal characteristics around Australasia. SLR is implemented through a uniform depth increase across the model domain, with a comparison between the implementation of coastal defences or allowing low-lying land to flood. The complex spatial response of the semi-diurnal M 2 constituent does not appear to be linear with the imposed SLR. The most predominant features of this response are the generation of new amphidromic systems within the Gulf of Carpentaria and large-amplitude changes in the Arafura Sea, to the north of Australia, and within embayments along Australia's north-west coast. Dissipation from M 2 notably decreases along north-west Australia but is enhanced around New Zealand and the island chains to the north. The diurnal constituent, K 1 , is found to decrease in amplitude in the Gulf of Carpentaria when flooding is allowed. Coastal flooding has a profound impact on the response of tidal amplitudes to SLR by creating local regions of increased tidal dissipation and altering the coastal topography. Our results also highlight the necessity for regional models to use correct open boundary conditions reflecting the global tidal changes in response to SLR. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Royal Anthropological Institute is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Across their range, mangroves are responding to coastal environmental change. However, separating the influence of human activities from natural events and processes (including that associated with climatic fluctuation) is often difficult. In the Gulf of Carpentaria, northern Australia (Leichhardt, Nicholson, Mornington Inlet, and Flinders River catchments), changes in mangroves are assumed to be the result of natural drivers as human impacts are minimal. By comparing classifications from time series of Landsat sensor data for the period 1987-2014, mangroves were observed to have extended seawards by up to 1.9 km (perpendicular to the coastline), with inland intrusion occurring along many of the rivers and rivulets in the tidal reaches. Seaward expansion was particularly evident near the mouth of the Leichhardt River, and was associated with peaks in river discharge with Li DAR data indicating distinct structural zones developing following each large rainfall and discharge event. However, along the Gulf coast, and particularly within the Mornington Inlet catchment, the expansion was more gradual and linked to inundation and regular sediment supply through freshwater input. Landward expansion along the Mornington Inlet catchment was attributed to the combined effects of sea level rise and prolonged periods of tidal and freshwater inundation on coastal lowlands. The study concluded that increased amounts of rainfall and associated flooding and sea level rise were responsible for recent seaward and landward extension of mangroves in this region. [ABSTRACT FROM AUTHOR]

In this work, variations in mass-induced sea surface height (SSH, ocean bottom pressure) in the Gulf of Carpentaria are investigated on seasonal to decadal timescales using altimetry data, Gravity Recovery and Climate Experiment (GRACE) estimates, and steric sea surface height measurements derived from subsurface temperature and salinity analyses. Seasonal variability in gulf-mean SSH can be attributed to local wind forcing. On an interannual and decadal timescale, SSH is the dominant factor affecting total sea surface height, and is related to large-scale modes such as the El Niño Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). Oceanic waves propagating from the western Pacific and the corresponding water exchange between the deep ocean and the shallow Gulf of Carpentaria, rather than local wind variability associated with climate modes, are responsible for the low-frequency variations in SSH in the gulf. Over 2003-2011, SSH rose at a rate of about 8.0 ± 1.5 mm/year, and the PDO accounted for about 65 % of gulf-scale mass variation. [ABSTRACT FROM AUTHOR]

Biodiversity assessments by research scientists are often logistically difficult and expensive to implement in remote areas. Locally-based approaches have the potential to overcome some of these challenges by capitalising on the knowledge and capacity of local people. Many Indigenous people in northern Australia are custodians of coastal areas that support globally significant populations of tropical marine mammals, including coastal dolphins and dugongs. The objective of our study was to design and implement a locally-based approach in a cross-cultural environment to assess the distribution of marine mammals in the remote waters of the Gulf of Carpentaria, Northern Territory. The study was conducted as a partnership between Yanyuwa Aboriginal families, research scientists, government officers and the li-Anthawirriyarra Sea Rangers. We conducted a series of participatory mapping workshops to share and record local observations of dolphins and dugongs. These observations provided the longitudinal information required to inform the design of the first dedicated marine mammal vessel survey in the Gulf of Carpentaria. The vessel surveys found three species of dolphins present in the area (Australian snubfin, humpback and bottlenose dolphins), even though sightings were low; dugongs being much more common. We found that the integrative and locally-based approach built the capacity of both the li-Anthawirriyarra Sea Rangers and research scientists to assess the distribution of marine mammals. If replicated over longer time-frames and coordinated over broader spatial scales, information on distribution and abundance derived from locally-based approaches has the potential to inform the status of marine mammals. [ABSTRACT FROM AUTHOR]

Dramatic changes in shellfishing behaviors occur across northern Australia during the late Holocene, marked most conspicuously by the cessation of large shell mound construction in some areas, and the reorganization of shellfishing behaviors towards more intensive production in the last 1,000 years. Excavations reveal rapid and widespread changes within coastal sites, an increasing diversification in overall subsistence resources, and patterns of increase in site establishment and use. Some of these changes have been argued to be associated with increasing climate variability and a trend towards increasing aridity during the late Holocene, thought to have transformed coastal ecosystems and mollusc availability. However, when these hypotheses are tested at the local level, more nuanced patterns of human-environment interaction emerge, which call into question interpretations based on broad-scale climate records. We suggest that disjunctions in the timing of the cessation of shell mound construction noted between the west and east Gulf of Carpentaria may be related, at least in part, to the timing and intensity of external cultural contacts with Macassan seafarers, associated with reorganization of mobility and production strategies, rather than as yet undemonstrated environmental changes impacting on shellfish availability. [ABSTRACT FROM PUBLISHER]

The article focuses on the definition of fire in the Carpentaria's southern Gulf in Australia. Topics discussed include the equivocation in perception suggesting the world was conceived of before turning to real, the role played by fire in the cultural ecology of life in the planet, and the conflict between Aboriginal and non-Aboriginal people on their understanding of fire. Also mentioned was the declaration of the Australian government in 2004 that the region was a fire natural disaster area.

Observations and analyses of low-level convergence lines over the Gulf of Carpentaria region of northeastern Australia made during the second and third Gulf Lines EXperiments (GLEX II and GLEX III) are reported. During GLEX II, the initiation of the North Australian Cloud Line (NACL) was documented using a small autonomous aircraft and two Doppler sodars. NACLs are long convergence lines that form on the western side of northern Cape York Peninsula and are typically marked by a line of contiguous cumulus or cumulus congestus cloud. The observations show that the degree of asymmetry between west-coast and east-coast sea breezes (as characterized by the wind field) depends on the strength of the background easterlies, and that NACLs develop only when the background easterlies are sufficiently large (≥ 5 m s−1). GLEX III focused on morning glories, which are (mostly) southwestward-moving bore-like convergence lines that originate over the southern part of the gulf region. The field experiment involved Doppler sodar measurements as well as high-temporal-resolution data from operational automatic weather stations. The sodar measurements showed that undular bore-like morning glory cloud lines develop only when the background easterlies are sufficiently weak (≤ 10 m s−1) and that strong bore-like morning glories develop when the background winds exceed about 10 m s−1. If the background easterlies are too strong, no morning glories develop. Numerical simulations show that the structure of convergence line produced depends on the strength of the collision between the sea breezes from each side of the Cape York Peninsula, which in turn depends on the strength of the background easterlies. When the easterlies are weak (≤ 10 m s−1), the sea breezes have similar depths and strengths, and their collision is relatively violent, whereas when the background easterlies are strong (> 10 m s−1) the sea breezes have very different depths and strengths and their collision is comparatively benign. [ABSTRACT FROM AUTHOR]

Anthropologists often construe “property” in terms of rights, obligations, and interests, or use “property” in a largely undefined way. The use of the language of rights as a metalanguage is questionable for it is culturally specific, having developed in the Early Modern period in Europe in the context of the spread of market relations and the growth of contract law. One might ask, how are “rights” expressed and constituted in the indigenous languages? The article examines the role of language in the constitution of possession relations with reference to three case studies: ownership of land by Kaiadilt people of Bentinck Island in the Gulf of Carpentaria, possession more generally among Navajo of the southwest United States, and family/household “property” of the Southern Song dynasty of China. It focuses on the constitution of possessors, possessions and connections between them, and the expression of norms entailed by relations between possessor and possessum. (Property, possession, rights, Kayardild language, Navajo language, Southern Song dynasty, metalanguage)* [ABSTRACT FROM AUTHOR]

The article discusses research on the discovery of the new species of Kanekonia leichhardti or Leichhardt's velvetfish from the eastern Gulf of Carpentaria in Queensland, published in 2013. A description of the new species is presented. The materials and methods used to conduct the study are also discussed.

The article provides photographic evidence of a White-throated Nightjar Eurostopodus mystacalis flying low above the sea in the Gulf of Carpentaria, Queensland, on August 25, 2010. Nightjars behaving similarly in the same area in the days before obtaining the conclusive photographs are also observed. It suggests that the Nightjars were on southerly migration, returning from their wintering sojourn in New Guinea to their breeding grounds in Australia. It also cites other relevant sightings and discusses the significance of this behaviour.

The diurnal and seasonal variations of the northern Australian dryline are examined by constructing climatologies of low-level dynamic and thermodynamic variables taken from the high-resolution Australian Bureau of Meteorology’s Limited Area Prediction Scheme (LAPS) forecasts from 2000 to 2003. The development of the dryline is analyzed within the framework of the frontogenesis function applied to the mixing ratio and the airstream diagnostics of Cohen and Schultz. A case study of 12–13 October 2002 illustrating the airmass boundaries over the Australian region is also examined. Daytime surface heating produces sea-breeze circulations around the coast and a large inland heat trough that extends east–west along northern Australia. At night, air parcels accelerate toward low pressure, increasing convergence and deformation within the heat trough. This sharpens the moisture gradient across the tropical and continental airmass boundary into a dryline. This is different than the dryline of the Great Plains in the United States, which generally weakens overnight. The Australian dryline is strongest in spring just poleward of the Gulf of Carpentaria, where the moisture gradient across the heat trough is enhanced by the coast, and the axis of dilatation is closely aligned with mixing ratio isopleths. The dryline is weakest in winter, when the heat trough is weak. The LAPS 3-h forecasts are in good agreement with observations obtained from the Automatic Weather Station network. The 3-h forecasts capture the observed diurnal and seasonal cycle of the airmass boundaries. However, the sea-breeze circulation and ageostrophic flow into the surface heat trough is limited by the model resolution. The LAPS 3-h forecasts may therefore underestimate the nocturnal intensification of the dryline, especially since the inland moisture content is overestimated. [ABSTRACT FROM AUTHOR]

Observations of northward-moving borelike convergence lines over the southern part of the Gulf of Carpentaria region of northern Australia are described. Eleven such disturbances were documented during the 45-day period of the 2002 Gulf Lines Experiment. Of these, six were classified as major and five as minor, depending on their coherence throughout the region. The mean synoptic conditions leading to the two types of events were found to differ. The data for the events provide further insight into the structure and origin of borelike disturbances in the region. Two of the major events, those of 28–29 September and 9 October, are particularly noteworthy. The first of these had a clear double-change structure at all surface stations in the southeastern gulf region with an undular borelike wave preceding and separating from an airmass change in the form of a dryline. It is probably one of the best documented cases of its type. The second, which was documented in unprecedented detail by an instrumented research aircraft, consisted of three separate disturbances: one moving from the southeast, one from the south, and one from the northeast, all of which collided over the gulf. It is believed that the aircraft measurements are the first of their kind anywhere in the world. The aircraft made two long low-level transects through the disturbances and a higher-level transect where they were colliding. Various soundings were also made. The aircraft data showed clearly the undular borelike nature of the southeasterly disturbance. Measured vertical velocities in the waves were as high as 3 m s-1 at a mean altitude of about 230 m. Vertical velocities as high as 5 m s-1 were measured in the region of the collision at an altitude of about 1 km. The longevity of the bores is not explained by the vertical structure of the Scorer parameter, which indicates a leaky waveguide. [ABSTRACT FROM AUTHOR]

Observations of dry-season north Australian cloud lines (NACLs) that form in the Gulf of Carpentaria region of northern Australia and the sea-breeze circulations that initiate them are described. The observations were made during the 2002 Gulf Lines Experiment (GLEX) and include measurements made by an instrumented research aircraft. The observations are compared with numerical simulations made from a two-dimensional cloud-scale model. Particular emphasis is placed on the interaction between the east coast and west coast sea breezes near the west coast of Cape York Peninsula. The sea breezes are highly asymmetric due to the low-level easterly synoptic flow over the peninsula. The west coast sea breeze is well defined with a sharp leading edge since the opposing flow limits its inland penetration, keeping it close to its source of cold air. In contrast, the east coast sea breeze is poorly defined since it is aided by the easterly flow and becomes highly modified by daytime convective mixing as it crosses over the peninsula. Both the observations and the numerical model show that, in the early morning hours, the mature NACL forms at the leading edge of a gravity current. The numerical model simulations show that this gravity current arises as a westward-moving land breeze from Cape York Peninsula. Convergence at the leading edge of this land breeze is accompanied by ascent, which when strong enough produces cloud. Observations show that the decay of the NACL is associated with a decline in the low-level convergence and a weakening of the ascent. [ABSTRACT FROM AUTHOR]

Mangrove forests are of high biological, economic, and ecological importance globally. Growing within the intertidal zone, they are particularly vulnerable to the effects of climate change in addition to being threatened on local scales by over-exploitation and aquaculture expansion. Long-term monitoring of global mangrove populations is therefore highly important to understanding the impact of these threats. However, data availability from satellites is often limited due to cloud cover. This problem can be mitigated using a season-trend modelling approach such as Continuous Monitoring of Land Disturbance (COLD). COLD operates by using every available observation on a pixel-wise basis, removing the need for whole cloud free images. The approach can be used to better classify land cover by taking into account the underlying seasonal variability, and can also be used to extrapolate between data points to obtain more accurate long term trends. To demonstrate the utility of COLD for global mangrove monitoring, we applied it to five study sites chosen to represent a range of mangrove species, forest types, and quantities of available data. The COLD classifier was trained on the Global Mangrove Watch 2010 dataset and applied to 30 years of Landsat data for each site. By increasing the period between model updates, COLD was successfully applied to all five sites (2253 scenes) in less than four days. The method achieved an overall accuracy of 92% with a User's accuracy of 77% and a Dice score of 0.84 for the mangrove class. The lowest User's accuracy was for North Kalimantan (49.9%) due to confusion with mangrove palms. However, the method performed extremely well for the Niger Delta from the 2000s onwards (93.6%) despite the absence of any Landsat 5 data. Observation of trends in mangrove extent over time suggests that the method was able to accurately capture changes in extent caused by the 2014/15 mangrove die-back event in the Gulf of Carpentaria and highlighted a net loss of mangroves in the Matang Forest Reserve over the last two decades, despite ongoing management. COLD is therefore a promising methodology for global, long-term monitoring of mangrove extent and trends. [ABSTRACT FROM AUTHOR]

Examines the chenier plain of the southern coast of the Gulf of Carpentaria, Northern Australia. Depositional model for a chenier plain; Formation of chenier ridges during periods of reduced sediment flux by wave induced sorting and redistribution process; Occurrence of an alternation of increased and decreased sediment flux from fluvial sources during the upper Holocene; Temporal fluctuations in rainfall over the drainage basin which surrounds the southern and eastern Gulf.