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Our understanding of bird migration is heavily biased toward long-distance movements in the Northern Hemisphere, 1,2,3 with only fragmented knowledge from the Southern Hemisphere. 4,5 In Australia, while some species migrate, 4,6,7,8 the timing and direction of large-scale, multi-species seasonal movements remain critically understudied due to the complexity of movement in this region and a lack of research personnel and infrastructure. 7,9 It is still unclear whether there are pronounced and structured mass movements resembling those in the Northern Hemisphere. 10,11,12 Here, we analyze data from a latitudinal transect of weather radars spanning the entire coastline of Eastern Australia to determine the magnitude, directions, timing, and variability of bird migration compared to that of Northern Hemisphere migration systems. Bird movements exhibited sequential seasonal peaks along a latitudinal gradient with seasonally contrasting flight directions, confirming that a structured bird migration system exists. Three features were distinct from Northern Hemisphere migrations. First, distinct movements occurred around sunrise with comparable magnitudes to nocturnal migration, likely representing a strong diurnal component to the bird movements. Second, migration intensity averaged 0.06 million birds km−1 in autumn, much lower than Northern Hemisphere migrations. 11,12,13 Finally, flight directions were more dispersed, and the timing and amount of migration were highly variable between years compared to Northern Hemisphere migration systems, perhaps in response to variable climate. 7 This first quantification of continental-scale movements in Australia revealed a distinctive migration system, and it suggests that much remains to be discovered about the ecological and evolutionary factors shaping animal migrations in the Southern Hemisphere. • Weather radar network reveals a structured bird migration system in East Australia • Sequential migration peaks move latitudinally, and directions reverse seasonally • Magnitude is smaller than in the Northern Hemisphere but with larger daytime activity • Direction, timing, and magnitude vary more between years than in North America Shi et al. show that a structured migration system with seasonal peaks and contrasting flight directions exists in Eastern Australia. Unlike in the Northern Hemisphere, Australian migrations show a significant proportion of diurnal movement, with lower intensity and greater variability in timing, direction, and magnitude across years. [ABSTRACT FROM AUTHOR]

Biogeography is a valid scientific endeavour for exploring diatom distributions because the concept of endemism is generally accepted and not considered an irrelevant idea – endemism is taken seriously because it has been documented for many species in many areas around the globe. But to study biogeography meaningfully one does not just need the recognition of endemism. What is required is a problem, such as explaining the diversity of species or species groups in the Southern hemisphere. This requires the identification of species or species groups that are demonstrated to be endemic in at least some of the areas of interest and are related in a very specific way (monophyly). This paper deals with the genus Fragilariforma, which has ca. 30 + included species (taxa) that can be divided into a Northern component and a Southern component, the latter potentially speaking to the origin of the southern hemisphere biota. [ABSTRACT FROM AUTHOR]

Subantarctic Nothofagus forests are the southernmost forests in the world, with negligible atmospheric nitrogen (N) deposition. Most paradigms about the role of ectomycorrhizal (ECM) fungi in N cycling and plant N uptake at high latitudes have been tested in boreal coniferous forests, while in the southern hemisphere, ECM hosts are primarily angiosperms. Using ITS1 meta‐barcoding, we characterized ECM and saprotrophic fungal communities in evergreen and deciduous Nothofagus forests forming monodominant and mixed stands in the archipelago of Tierra del Fuego (Chile and Argentina). We assessed the N economy of Nothofagus by correlating host species with fungal relative abundances, edaphic variables, net N mineralization, microbial biomass N and the activity of eight extracellular soil enzymes activities. The N economy of deciduous N. pumilio forests was strikingly similar to boreal coniferous forests, with the lowest inorganic N availability and net N mineralization, in correlation to higher relative abundances of ECM fungi with enzymatic capacity for organic N mobilization (genus Cortinarius). In contrast, the N economy of evergreen N. betuloides forests was predominantly inorganic and correlated with ECM lineages from the family Clavulinaceae, in acidic soils with poor drainage. Grassy understory vegetation in deciduous N. antarctica forests likely promoted saprotrophic fungi (i.e., genus Mortierella) in correlation with higher activities of carbon‐degrading enzymes. Differences between Nothofagus hosts did not persist in mixed forests, illustrating the range of soil fertility of these ECM angiosperms and the underlying effects of soil and climate on Nothofagus distribution and N cycling in southern Patagonia. [ABSTRACT FROM AUTHOR]

The regional climate of New Zealand's South Island is shaped by the interaction of the Southern Hemisphere westerlies with the complex orography of the Southern Alps. Due to its isolated geographical setting in the south‐west Pacific, the influence of the surrounding oceans on the atmospheric circulation is strong. Therefore, variations in sea surface temperature (SST) impact various spatial and temporal scales and are statistically detectable down to temperature anomalies and glacier mass changes in the high mountains of the Southern Alps. To enable future studies on the processes that govern the link between large‐scale SST and local‐scale high‐mountain climate, we utilized dynamical downscaling with the Weather Research and Forecasting (WRF) model to produce a regional atmospheric modelling dataset for the South Island of New Zealand over a 16‐year period between 2005 and 2020. The 2 km horizontal resolution ensures realistic representation of high‐mountain topography and glaciers, as well as explicit simulation of convection. The dataset is extensively evaluated against observations, including weather station and satellite data, on both regional (in the inner domain) and local (on Brewster Glacier in the Southern Alps) scales. Variability in both atmospheric water content and near‐surface meteorological conditions is well captured, with minor seasonal and spatial biases. The local high‐mountain climate at Brewster Glacier, where land use and topographic model settings have been optimized, yields remarkable accuracy on both monthly and daily time scales. The data provide a valuable resource to researchers from various disciplines studying the local and regional impacts of climate variability on society, economies and ecosystems in New Zealand. The model output from the highest resolution model domain is available for download in daily temporal resolution from a public repository at the German Climate Computation Center (DKRZ) in Hamburg, Germany (Kropač et al., 2023; 16‐year WRF simulation for the Southern Alps of New Zealand, World Data Center for Climate (WDCC) at DKRZ [data set]. https://doi.org/10.26050/WDCC/NZ‐PROXY_16yrWRF). [ABSTRACT FROM AUTHOR]

To reduce influenza-associated morbidity and mortality, countries in South America recommend annual influenza vaccination for persons at high risk for severe influenza illness, including young children, persons with preexisting health conditions, and older adults. Interim estimates of influenza vaccine effectiveness (VE) from Southern Hemisphere countries can provide early information about the protective effects of vaccination and help guide Northern Hemisphere countries in advance of their season. Using data from a multicountry network, investigators estimated interim VE against influenzaassociated severe acute respiratory illness (SARI) hospitalization using a test-negative case-control design. During March 13– July 19, 2024, Argentina, Brazil, Chile, Paraguay, and Uruguay identified 11,751 influenza-associated SARI cases; on average, 21.3% of patients were vaccinated against influenza, and the adjusted VE against hospitalization was 34.5%. The adjusted VE against the predominating subtype A(H3N2) was 36.5% and against A(H1N1)pdm09 was 37.1%. These interim VE estimates suggest that although the proportion of hospitalized patients who were vaccinated was modest, vaccination with the Southern Hemisphere influenza vaccine significantly lowered the risk for hospitalization. Northern Hemisphere countries should, therefore, anticipate the need for robust influenza vaccination campaigns and early antiviral treatment to achieve optimal protection against influenza-associated complications. [ABSTRACT FROM AUTHOR]

A new genus and species of staphylinid beetle, Cretafrica orapensis gen. nov. et sp. nov. is described using a single well-preserved impression fossil from an Upper Cretaceous fossil insect deposit, the Orapa Diamond Mine in Botswana. Cretafrica is placed in the extant subfamily Mycetoporinae based on its general habitus, typical sublimuloid medium-to-large body form, elongated head, visible ridge on ventral side of head under eyes, antennomeres increasing in length and width apically, scutellum with basal carina that is distinctly divided medially, elevated area along suture of the elytra, and presumably large metacoxae, and tapering abdomen. It differs from other Mycetoporinae by its triangular head and elytra with broadly rounded apico-lateral margins. A possible preservation distortion illustrates brush-like or fork-like mouthparts. The fossil insect may have been found in forest litter or fresh and rotting mushrooms at Orapa. It confirms the widespread distribution of mycetoporines with phytophagous or mycophagous lifestyles during the mid-Cretaceous. Moreover, like other described fossil staphylinids, the fossil portrays morphological stasis dating back to the Cretaceous. It further confirms the proposed punctuated equilibrium pattern of evolution. [ABSTRACT FROM AUTHOR]

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Premise: The Cenozoic Macquarie Harbour Formation (MHF) hosts one of the oldest and southernmost post‐Cretaceous fossil plant assemblages in Australia. Coinciding with the Early Eocene Climatic Optimum (EECO) and predating the breakup of Australia from Antarctica, it offers critical data to study the diversity and extent of the Austral Polar Forest Biome, and the floristic divergence between Australasia and South America resulting from the Gondwana breakup. Methods: The micromorphology and macromorphology of new fossil plant compressions from the MHF were described and systematically analyzed. Previously published non‐flowering plant records were reviewed and revised. Macrofossil abundance data were provided. The flora was compared with other early Paleogene assemblages from across the Southern Hemisphere. Results: Twelve species of non‐flowering plants were identified from the macrofossil record. Conifers include Araucariaceae (Araucaria macrophylla, A. readiae, A. timkarikensis sp. nov., and Araucarioides linearis), Podocarpaceae (Acmopyle glabra, Dacrycarpus mucronatus, Podocarpus paralungatikensis sp. nov., and Retrophyllum sp.), and Cupressaceae (Libocedrus microformis). Dacrycarpus linifolius was designated a junior synonym of D. mucronatus. Further components include a cycad (Bowenia johnsonii, Zamiaceae), a pteridosperm (Komlopteris cenozoicus, Umkomasiaceae), and a fern (Lygodium dinmorphyllum, Schizaeaceae). Conclusions: The fossil assemblage represents a mixed near‐polar forest with a high diversity of conifers. The morphology and preservation of several species indicate adaptations to life at high latitudes. The coexistence of large‐ and small‐leaved conifers implies complex, possibly open forest structures. Comparisons with contemporaneous assemblages from Argentina support a circumpolar biome during the EECO, reaching from southern Australia across Antarctica to southern South America. [ABSTRACT FROM AUTHOR]

Premise: Fossil infructescences and isolated fruits with characters of Malvoideae, a subfamily of Malvaceae (mallow family), were collected from early Eocene sediments in Chubut, Argentina. The main goals of this research are to describe and place these fossils systematically, and to explore their biogeographical implications. Methods: Fossils were collected at the Laguna del Hunco site, Huitrera Formation, Chubut, Patagonia, Argentina. They were prepared, photographed, and compared with extant and fossil infructescences and fruits of various families using herbarium material and literature. Results: The infructescences are panicles with alternate arrangement of fruits. They bear the fruits on short pedicels that are subtended by a bract; the fruits display an infracarpelar disk and split to the base into five ovate sections interpreted as mericarps. Each mericarp is characterized by an acute apex and the presence of a longitudinal ridge. The isolated fruits show the same features as those on the infructescences. The fossils share unique features with members of the cosmopolitan family Malvaceae, subfamily Malvoideae. Conclusions: The fossils have a unique combination of characters that does not conform to any previously described genus, justifying the erection of a new genus and species, Uiher karuen. This new taxon constitutes the first known Malvoideae reproductive fossils of the Southern Hemisphere, expanding the distribution of Malvoideae during the early Eocene. [ABSTRACT FROM AUTHOR]

Abstract The regional climate of New Zealand's South Island is shaped by the interaction of the Southern Hemisphere westerlies with the complex orography of the Southern Alps. Due to its isolated geographical setting in the south‐west Pacific, the influence of the surrounding oceans on the atmospheric circulation is strong. Therefore, variations in sea surface temperature (SST) impact various spatial and temporal scales and are statistically detectable down to temperature anomalies and glacier mass changes in the high mountains of the Southern Alps. To enable future studies on the processes that govern the link between large‐scale SST and local‐scale high‐mountain climate, we utilized dynamical downscaling with the Weather Research and Forecasting (WRF) model to produce a regional atmospheric modelling dataset for the South Island of New Zealand over a 16‐year period between 2005 and 2020. The 2 km horizontal resolution ensures realistic representation of high‐mountain topography and glaciers, as well as explicit simulation of convection. The dataset is extensively evaluated against observations, including weather station and satellite data, on both regional (in the inner domain) and local (on Brewster Glacier in the Southern Alps) scales. Variability in both atmospheric water content and near‐surface meteorological conditions is well captured, with minor seasonal and spatial biases. The local high‐mountain climate at Brewster Glacier, where land use and topographic model settings have been optimized, yields remarkable accuracy on both monthly and daily time scales. The data provide a valuable resource to researchers from various disciplines studying the local and regional impacts of climate variability on society, economies and ecosystems in New Zealand. The model output from the highest resolution model domain is available for download in daily temporal resolution from a public repository at the German Climate Computation Center (DKRZ) in Hamburg, Germany (Kropač et al., 2023; 16‐year WRF simulation for the Southern Alps of New Zealand, World Data Center for Climate (WDCC) at DKRZ [data set]. https://doi.org/10.26050/WDCC/NZ‐PROXY_16yrWRF).

The Triassic record of modern sharks, rays, and skates (Elasmobranchii) is scattered and geographically biased towards the Northern Hemisphere and Europe in particular. Here, we report the first Triassic elasmobranch teeth from the Southern Hemisphere, originating from Norian strata of New Zealand. The teeth are few in numbers but relatively well preserved and indicate the presence of three different taxa, that all can be included in the extinct order Synechodontiformes. Different dental characters and combinations of characters suggest that the teeth represent previously undescribed species with apparently no close relatives in the Triassic elasmobranch record from the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Biomass burning plays an important role in climate-forcing and atmospheric chemistry. The drivers of fire activity over the past two centuries, however, are hotly debated and fueled by poor constraints on the magnitude and trends of preindustrial fire regimes. As a powerful tracer of biomass burning, reconstructions of paleoatmospheric carbon monoxide (CO) can provide valuable information on the evolution of fire activity across the preindustrial to industrial transition. Here too, however, significant disagreements between existing CO records currently allow for opposing fire histories. In this study, we reconstruct a continuous record of Antarctic ice coreCObetween 1821 and 1995CE to overlap with direct atmospheric observations. Our record indicates that the Southern Hemisphere CO burden ([CO]) increased by 50% from a preindustrial mixing ratio of ca. 35 ppb to ca. 53 ppb by 1995 CE with more variability than allowed for by state-of-the-art chemistry-climate models, suggesting that historic CO dynamics have been not fully accounted for. Using a 6-troposphere box model, a 40 to 50% decrease in Southern Hemisphere biomass-burning emissions, coincident with unprecedented rates of early 20th century anthropogenic land-use change, is identified as a strong candidate for this mismatch. [ABSTRACT FROM AUTHOR]

Thermal Thellier type palaeointensity (PI) experiments are the most popular technique in determining strength of the past geomagnetic field (GMF). However, the method often encounters high failure rate. Mineral magnetic properties can provide useful information to enhance the success rate. We conducted the first ever detailed mineral magnetic and Thellier type PI experiments on lava flows within a 1250 m stratigraphic section of the largest end-Cretaceous (~ 65–66 Ma) Deccan flood basalt. The lava flows mostly contain pseudo single domain (PSD) titano-magnetite/magnetite with, low viscosity index (≤ 5), high/moderate Koenigsberger ratio (Qn > 10/ < 10), isothermal remanent magnetisation parameters typical of ferromagnetic minerals, saturation remanence magnetization to saturation magnetization ratio (Mrs/Ms: 0.05–0.31), coercivity of remanence to coercive force ratio (Hcr/Hc: 1.53–3.72) and a single magnetic component pointing to origin or a minor viscous component during alternating field (AF) demagnetizations,. Their thermomagnetic responses are broadly group into 3 categories. The type 1 displays near perfect reversible heating/cooling curves with high Curie temperatures of 570–600 °C; other two types have either widely separated (type2) or quite dissimilar (type 3) heating/cooling curves. 76 samples from 19 flows were subjected to ZI (Zero field-Infield) experiments with pTRM and pTRM tail checks. 24 samples from eight flows display reasonable NRM-TRM linearity and positive pTRM checks and satisfy strict reliability criteria. 42 samples from 11 flows do not satisfy the reliability criteria. Samples of reliable PI results are all characterized by reversible thermomagnetic behaviour with excellent stability during AF/thermal treatment. Samples that failed to meet reliability criteria possess irreversible/widely separated thermomagnetic heating/cooling curves or poor stability to AF/thermal treatment but not significantly different from the successful samples in other magnetic properties. Thus, thermomagnetic behaviour and stability to AF/thermal treatment appear to be the overweighing factors than other mineral magnetic characteristics that govern the success rate of thermal PI experiments. The PI values of upper normal (29N) flows are relatively higher than the lower reverse (29R) flows; this suggests minor time lag in cooling of successive flows. The time averaged PI estimate is an important end-Cretaceous contribution from the Indian subcontinent to the poorly represented database of southern hemisphere. [ABSTRACT FROM AUTHOR]

The Southern Hemisphere climate and weather are affected by several modes of variability and climate phenomena across different time and spatial scales. An additional key component of the atmosphere dynamics that greatly influences weather is quasi-stationary Rossby waves, which attract particular interest as they are often associated with synoptic-scale extreme events. In the Southern Hemisphere extratropical circulation, the most prominent quasi-stationary Rossby wave pattern is the zonal wavenumber 3 (ZW3), which has been shown to have impacts on meridional heat and momentum transport in mid- to high latitudes and on the Antarctic sea ice extent. However, little is known about its impacts outside of polar regions. In this work, we use ERA5 reanalysis data on monthly time scales to explore the influence of phase and amplitude of ZW3 on temperature and precipitation across the Southern Hemisphere midlatitudes. Our results show a significant impact in various regions for all seasons. One of the most substantial effects is observed in precipitation over southeastern Brazil during austral summer, where different phases of the ZW3 force opposite anomalies. When using the ZW3 phase and amplitude as prior information, the probability of occurrence of precipitation extremes in this region increases up to three times. Additionally, we find that this ZW3 weather signature is largely independent of the zonally symmetric Southern Annular Mode (SAM); neither does it seem to be linked to El Niño–Southern Oscillation (ENSO) or Indian Ocean dipole (IOD) signal. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the reproductive parameters of porbeagle shark in the Southwest Atlantic Ocean and thus characterize the adult fraction of this population. Therefore, 1012 specimens were measured by scientific observers on board the commercial trawl fleet operating south of 50° S. The size range of the specimens was from 77 to 292 cm fork length (LF). The mean size at maturity was estimated to be 153 cm LF for males and 172 cm LF for females. Porbeagle shark catches were recorded throughout the year, with the highest frequency occurring between November and June. The presence of pregnant females was observed from December to July, along with an increase in the average size of embryos in each litter. The information presented in this study improves the knowledge of the reproductive biology and allows to propose a migratory pattern of adult porbeagle females in the Southwest Atlantic Ocean. The likely seasonal increase in vulnerability of this shark to austral trawl fishery, despite all conservation management measures established in Argentina, underscores the importance of promoting its proper management and conservation given the need to improve understanding of porbeagle population dynamics in the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

We describe a diverse aquatic insect assemblage from McGraths Flat, a Miocene Lagerstätte in central New South Wales, Australia that includes representatives of Sialidae, Limoniidae, Chironomidae and Chaoboridae. The aquatic insect fossils from this deposit consist predominantly of larvae. These include a new species of phantom midge (Chaoborus, Chaoboridae), three morphotypes of non‐biting midges (Chironomidae), one morphotype of cranefly (Limoniidae) and one morphotype of alderfly (Sialidae). The large number of fossil specimens enabled us to study the ontogeny of the new midge species. We discerned growth rates in fossil larvae, using morphometry of all four instars of Chaoborus. The simultaneous presence of taxa associated with still water and taxa associated with flowing water supports the hypothesis that McGraths Flat was deposited in an isolated water body (oxbow lake/billabong) with influence from a river during high water events. [ABSTRACT FROM AUTHOR]

Bioerosion traces are a powerful tool for reconstructing benthic paleo-communities through the geological record. The late Quaternary marine deposits of Patagonia (Argentina) are elongated ridges parallel to the present coast, rich in sand, gravel and shells, the latter being the main substrate for bioerosion traces. However, the ichnological studies in the Quaternary are scarce in high latitudes of the Southern Hemisphere. This work describes for the first time the bioerosion traces recorded in shells belonging to diverse taxa of mollusc from Quaternary deposits in Puerto Lobos, Southern of San Matias Gulf (Patagonia, Argentina). This study complements the scarce information on bioerosion traces in the Southern Hemisphere. A total of 710 mollusc shells were obtained from four Quaternary beach ridges at Puerto Lobos. As a result, 15 ichnotaxa were recorded for the first time in the site, 13 of them for the first time in the Holocene of San Matías Gulf. Through qualitative analysis, bioerosion patterns were observed in the late Quaternary of Puerto Lobos. The abundance of worm and sponge borings in the Pleistocene could be related to warm and sediment-free waters. On the contrary, the results of the bioerosion study in the Holocene and recent samples were very similar. This could indicate that the same environmental factor controlled both bioerosion patterns. For the Holocene, it was observed that the bioerosion pattern is mainly represented by trace produced by suspension and filter-feeding organisms, such as bryozoans, among others. Together with the increase in ichnodiversity, this could indicate an increase in nutrient availability in the San Matías Gulf associated with upwelling events. Therefore, our results reinforce the hypothesis proposed by previous authors that the upwelling events currently observed in the study area began during the mid-Holocene. [ABSTRACT FROM AUTHOR]

Chinook salmon (Oncorhynchus tshawytscha) is invading South America. Both the high plasticity and genetic diversity of introduced propagules have been hypothesized to be responsible for the success of this species' invasion. Yet, the influence of environmental variability on the expressed phenology of the adult spawning migration has been overlooked in this region. Here, we examined the consistency in timing, duration, and relative abundance of adult salmon migrants and their associations with environmental river conditions and surrounding ocean in a regulated river system in Patagonia. We conducted monthly long-term snorkeling fish surveys (2010–2019) and collected associated environmental information from the river and ocean. We observed a recent increase in duration of the spawning migration and a decline in the relative abundance of adult migrants. A warming phase of the Southern Pacific Ocean (during the two previous years) was associated to an extended migration season, whereas a colder river in fall was associated to a lower number of adult migrants. Collectively, our findings suggest that rapid phenological shifts could occur in a recently established salmon population (circa 1980). This process could be explained by novel selective pressures and expression of life history traits in response to novel environmental regimes. Further long-term surveys of introduced salmon can aid in parsing the relationships between environmental regimes and the biology and persistence of these self-sustained populations. [ABSTRACT FROM AUTHOR]

Abstract Subantarctic Nothofagus forests are the southernmost forests in the world, with negligible atmospheric nitrogen (N) deposition. Most paradigms about the role of ectomycorrhizal (ECM) fungi in N cycling and plant N uptake at high latitudes have been tested in boreal coniferous forests, while in the southern hemisphere, ECM hosts are primarily angiosperms. Using ITS1 meta‐barcoding, we characterized ECM and saprotrophic fungal communities in evergreen and deciduous Nothofagus forests forming monodominant and mixed stands in the archipelago of Tierra del Fuego (Chile and Argentina). We assessed the N economy of Nothofagus by correlating host species with fungal relative abundances, edaphic variables, net N mineralization, microbial biomass N and the activity of eight extracellular soil enzymes activities. The N economy of deciduous N. pumilio forests was strikingly similar to boreal coniferous forests, with the lowest inorganic N availability and net N mineralization, in correlation to higher relative abundances of ECM fungi with enzymatic capacity for organic N mobilization (genus Cortinarius). In contrast, the N economy of evergreen N. betuloides forests was predominantly inorganic and correlated with ECM lineages from the family Clavulinaceae, in acidic soils with poor drainage. Grassy understory vegetation in deciduous N. antarctica forests likely promoted saprotrophic fungi (i.e., genus Mortierella) in correlation with higher activities of carbon‐degrading enzymes. Differences between Nothofagus hosts did not persist in mixed forests, illustrating the range of soil fertility of these ECM angiosperms and the underlying effects of soil and climate on Nothofagus distribution and N cycling in southern Patagonia.

Abstract During the middle Permian through the Triassic, Tasmania moved from paleo-latitudes of 78° to 69°S, wedged between Antarctica and Australia, within the paleo-South polar circle. During this time, significant global carbon cycle disturbances triggered major environmental and climatic changes and mass extinction events globally. The Bicheno-5 core from Eastern Tasmania, Australia, provides the opportunity to examine middle Permian and Upper Triassic sediments from the paleo-Antarctic, using high-resolution organic carbon isotope (δ13CTOC) chemostratigraphy, pXRF, and sedimentology, combined with new palynological data integrated with the existing radiometric age model. While there is a significant unconformity in the Upper Permian to the middle Triassic associated with eustatic sea-level fall as a result of regional uplift in eastern Australia, three distinct carbon isotope excursions (CIEs), characterized by negative shifts of up to − 6 ‰ were identified; the middle Permian Guadalupian Carbon Isotope Excursions (G-CIE), the Carnian Pluvial Episode (CPE), and the mid-Norian Event (MNE). These three events highlight a significant climate shift through glacial and interglacial cycles to warmer non-glacial intervals in the Late Triassic, with evidence of the polar record of the Carnian Pluvial Episode and the mid-Norian Event, which are poorly studied in the Southern Hemisphere, specifically within the Paleo-Antarctic circle.

Skillful prediction of the Southern Hemisphere (SH) eddy-driven jet is crucial for representation of mid-to-high-latitude SH climate variability. In the austral spring-to-summer months, the jet and the stratospheric polar vortex variabilities are strongly coupled. Since the vortex is more predictable and influenced by long-lead drivers 1 month or more ahead, the stratosphere is considered a promising pathway for improving forecasts in the region on subseasonal to seasonal (S2S) time scales. However, a quantification of this predictability has been lacking, as most modeling studies address only one of the several interacting drivers at a time, while statistical analyses quantify association but not skill. This methodological gap is addressed through a knowledge-driven probabilistic causal network approach, quantified with seasonal ensemble hindcast data. The approach enables to quantify the jet's long-range predictability arising from known late-winter drivers, namely, El Niño–Southern Oscillation (ENSO), Indian Ocean dipole (IOD), upward wave activity flux, and polar night jet oscillation, mediated by the vortex variability in spring. Network-based predictions confirm the vortex as determinant for skillful jet predictions, both for the jet's poleward shift in late spring and its equatorward shift in early summer. ENSO, IOD, late-winter wave activity flux, and polar night jet oscillation only provide moderate prediction skill to the vortex. This points to early spring submonthly variability as important for determining the vortex state leading up to its breakdown, creating a predictability bottleneck for the jet. The method developed here offers a new avenue to quantify the predictability provided by multiple, interacting drivers on S2S time scales. Significance Statement: Predictions of the Southern Hemisphere midlatitude jet stream are crucial for skillful forecasts of the austral mid-to-high latitudes. Several oceanic and atmospheric phenomena could, if better represented in models, improve spring-to-summer jet predictions on subseasonal to seasonal time scales. However, the combined potential skill arising from the inclusion of such phenomena has not been quantified. This study does so by using a probabilistic causal network model, representing the connections between those drivers and the jet with conditional probabilities, trained on large sets of model data. The stratospheric polar vortex is confirmed as crucial predictor of jet variability but is itself hard to predict a month in advance due to submonthly variability, creating a predictability bottleneck for the jet. [ABSTRACT FROM AUTHOR]

The interannual variation of intraseasonal (10–30-day) oscillation (ISO) intensity for the eastward- and westward- propagating types over the mid-high latitudes in austral summer is studied. It indicates that during strong ISO years, the wave train has a larger amplitude and wider zonal influencing range. The wave train propagates eastward in both strong and weak eastward-propagating ISO years, while it propagates westward only in strong westward-propagating ISO years. One possible explanation for the larger magnitude of the wave train in strong ISO years is that the ISO perturbation acquires more energy from the mean flow through the barotropic kinetic energy and potential energy conversion. Based on the diagnostic results of the geopotential height trend, the maximum contributor to the eastward propagation is the same during strong and weak ISO years, as well as for the westward propagation. However, the relative contribution of the relative vorticity's meridional advection in weak years is smaller than that in strong years, which may be the reason why there is no significant westward propagation in weak ISO years. Due to the difference in amplitude and influencing range of the wave train during strong and weak ISO years, the two ISO types have different effects on the surface air temperate over land areas at the Southern Hemisphere. The interannual variation of the eastward-propagating ISO intensity appears to be linked to the El Niño-Southern Oscillation and Southern Annular Mode, while the westward-propagating ISO appears unrelated to them. [ABSTRACT FROM AUTHOR]

During the middle Permian through the Triassic, Tasmania moved from paleo-latitudes of 78° to 69°S, wedged between Antarctica and Australia, within the paleo-South polar circle. During this time, significant global carbon cycle disturbances triggered major environmental and climatic changes and mass extinction events globally. The Bicheno-5 core from Eastern Tasmania, Australia, provides the opportunity to examine middle Permian and Upper Triassic sediments from the paleo-Antarctic, using high-resolution organic carbon isotope (δ13CTOC) chemostratigraphy, pXRF, and sedimentology, combined with new palynological data integrated with the existing radiometric age model. While there is a significant unconformity in the Upper Permian to the middle Triassic associated with eustatic sea-level fall as a result of regional uplift in eastern Australia, three distinct carbon isotope excursions (CIEs), characterized by negative shifts of up to − 6 ‰ were identified; the middle Permian Guadalupian Carbon Isotope Excursions (G-CIE), the Carnian Pluvial Episode (CPE), and the mid-Norian Event (MNE). These three events highlight a significant climate shift through glacial and interglacial cycles to warmer non-glacial intervals in the Late Triassic, with evidence of the polar record of the Carnian Pluvial Episode and the mid-Norian Event, which are poorly studied in the Southern Hemisphere, specifically within the Paleo-Antarctic circle. [ABSTRACT FROM AUTHOR]

The Antarctic seaspider Pentanymphon antarcticum is a benthic species in the Southern Ocean, but little is known about its pathogen profile. In this study, we provide a draft genome for a new iridovirus species that has been identified using metagenomic techniques. The draft genome totals 157 260 bp and encodes 188 protein-coding genes. The virus shows greatest protein similarity to a 'carnivorous sponge-associated iridovirus' from a deep-sea sponge host. This study represents the first discovery of a pycnogonid iridovirus and the first iridovirus from the Antarctic region. [ABSTRACT FROM AUTHOR]

International trade in table grapes is expanding rapidly, with Peru overtaking South Africa as the second-largest exporter from the Southern Hemisphere behind Chile. The primary objective of the study was to the determine whether South Africa, with 75% of its exports destined for Europe, will be negatively affected by changes in Peru and Chile's export orientation. This question is addressed by breaking it down into four key factors. The first is the role of policy by applying Anderson et al.'s (2006) empirical framework of nominal rate of assistance (NRA) followed by measures of competitiveness, namely relative trade advantage (RTA), normalised revealed comparative advantage (NRCA) and the logarithmic relative export advantage (InRXA). The last two measures – indirect freight cost and trade barriers - zoom in on trade from one country to a specific destination. The results and discussion highlight that Peru, operating in close to a zero-distorted environment, has the potential to increase its competitiveness in the global table grape market. Whilst South Africa's table grape exporters also have this potential, given the advantages of a depreciating rand, broader and more favourable market access outside the EU and UK is paramount. [ABSTRACT FROM AUTHOR]

In recent decades, there have been significant problems worldwide related to global warming and the intensification of extreme temperature and rainfall events. This research evaluated daily temperature and rainfall indices trends to identify whether warming signals have occurred in South Australia over the past fifty years. Extreme cold, hot, and rainfall events were calculated using climatic data from 37 weather stations. A Mann–Kendall test was used for trend analysis with Sen's estimator. As a result, we determined that for the 1970–2021 period, the maximum and minimum temperatures increased by 1.1 and 0.7 °C, respectively, while precipitation had a negative trend (−52.2 mm per period). Since statistical significance was found in analysing extreme cold and hot events, we find that warming signals have several impacts on South Australia. In the case of rainfall events, we identified a heterogeneous pattern characterised by a reduction in the annual amount and an increase in extreme rainfall events. The findings enable us to conclude that the area shows signs of global warming that could affect the intensity and magnitude of droughts. This information is essential for continuing with current management strategies to adapt and mitigate the effects of global warming in South Australia. [ABSTRACT FROM AUTHOR]

This paper examines sightings of dwarf minke whales during the SOWER cruises. A total of 12 sightings were made between 1994/95 and 2003/04, across a relatively wide latitude (37°S–62°S) but limited longitude, between IWC Management Area III (0–70°E) and V (130°E–170°W), with no sightings in Area I (0–60°W) or II (60°W–120°W). Despite this low number of sightings, most were close to the Antarctic Convergence at 58°S–65°S. There may be some seasonality in their southbound migration. [ABSTRACT FROM AUTHOR]

Abiostratigraphic assessment of the benthic foraminiferal record at International Ocean Discovery Program (IODP) Site U1513 in the Mentelle Basin (southeast Indian Ocean, offshore western Australia), yielding a Turonian through Santonian deep-water benthic foraminiferal assemblage is presented. Predominantly calcareous deep-water benthic foraminifera are recovered, whereas agglutinated benthic taxa show a rare occurrence. Epifaunal benthic foraminifera make up ~50% of the total assemblage during the Turonian to Santonian. The most frequently recorded taxa are gavelinellids and gyroidinoids. Adistal, bathyal depositional environment is inferred. Two distinct benthic foraminiferal associations, the Gavelinella berthelini association and the Notoplanulina rakauroana association, were identified in the 160 m-thick succession, and together they yield over 190 taxa. At Site U1513 the occurrence of important benthic foraminiferal markers such as Gavelinella berthelini and the Notoplanulina lineage allows a good correlation with other localities in the southern hemisphere and tentatively with the Pacific Realm. Gavelinella bethelini, which is present from the base of the Turonian succession, shows its last occurrence shortly after the Turonian/Coniacian boundary. Notoplanulina rakauroana is recorded to range from the lower Coniacian through the uppermost Santonian. Throughout the Southern Hemisphere, a similar sequence of benthic foraminiferal bioevents in the Upper Cretaceous can be identified at the Walvis Ridge, in South Africa, Argentina, Southern India, the Kerguelen Plateau, the Great Australian Bight, and in New Zealand. This study aims at contributing to the development of an Upper Cretaceous calcareous benthic foraminiferal zonation applicable to the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

Apomictic plants mostly occur at higher latitudes and higher elevations, where they tend to occupy deglaciated areas. By analysing samples of the alpine floras of different latitudinal zones of the Americas (Argentina, Bolivia, Ecuador, USA), we investigated whether the proportion of gametophytic apomixis is comparable between the temperate alpine zones of the Northern Hemisphere and the Southern Hemisphere and whether the proportion of apomictic species increases from the alpine tropics towards the temperate alpine zone. The reproductive systems of 196 species and 275 individuals were determined by a flow-cytometric seed screening of 999 seeds. Phylogenetic logistic regression was used to evaluate differences in the proportion of apomictic species in samples of regional alpine floras. The apomictic embryo:endosperm ratio was determined for 33 species (two pseudogamous species and 31 species with autonomous apomixis) belonging to 28 genera of 13 families. The probability of a species being apomictic did not significantly differ between the regions. The highest probability of a species being apomictic was estimated for the northern temperate zone (29.6%), followed by the tropical zone (12.5%), and the southern temperate zone (11.9%). Our results show that asexual plant reproduction by apomixis is not restricted to the alpine zone of the Northern Hemisphere and its representation in alpine floras of the Southern Hemisphere, including the alpine tropics, has been substantially underestimated. [ABSTRACT FROM AUTHOR]

This document provides an outsider's perspective on the liturgical scene in the United States, comparing it to the author's experiences in Australia. The author notes the multicultural nature of American churches, with different ethnic groups often having their own churches, while Australian churches are more inclusive and diverse. The document also discusses the importance of indigenous culture and Christianity in Australia, which is not given much attention in the US liturgical field. The author highlights the performative culture and unbound imagination of US rituals, contrasting it with the more subdued approach preferred by Australian communities. The article also explores the influence of political culture on worship and the challenges of adapting liturgical resources from the US to other contexts. It concludes by acknowledging the valuable contributions of US liturgical scholarship, particularly in the areas of social justice and feminist thought. [Extracted from the article]

Subseasonal‐to‐seasonal (S2S) prediction has gained momentum in the recent past as a need for predictions between the weather forecasting timescale and seasonal timescale exists. The availability of S2S databases makes prediction and predictability studies possible over all the regions of the globe. Most S2S studies are, however, relevant to the northern hemisphere. In this review, the S2S literature relevant to the southern hemisphere (SH) are presented. Predictive skill, sources of predictability, and the application of S2S predictions are discussed. Indications from the subseasonal predictability studies for the SH regions suggest that predictive skill is limited to 2 weeks in general, particularly for temperature and rainfall, which are the variables most frequently investigated. However, temperature has enhanced skill compared to rainfall. More S2S prediction studies that include the quantification of the sources of predictability and the identification of windows of opportunity need to be conducted for the SH, particularly for the southern African region. The African continent is vulnerable to weather‐ and climate‐related disasters, and S2S forecasts can assist in alleviating the risk of such disasters. [ABSTRACT FROM AUTHOR]

As charismatic and iconic species, penguins can act as "ambassadors" or flagship species to promote the conservation of marine habitats in the Southern Hemisphere. Unfortunately, there is a lack of reliable, comprehensive, and systematic analysis aimed at compiling spatially explicit assessments of the multiple impacts that the world's 18 species of penguin are facing. We provide such an assessment by combining the available penguin occurrence information from Global Biodiversity Information Facility (>800,000 occurrences) with three main stressors: climate‐driven environmental changes at sea, industrial fisheries, and human disturbances on land. Our analyses provide a quantitative assessment of how these impacts are unevenly distributed spatially within species' distribution ranges. Consequently, contrasting pressures are expected among species, and populations within species. The areas coinciding with the greatest impacts for penguins are the coast of Perú, the Patagonian Shelf, the Benguela upwelling region, and the Australian and New Zealand coasts. When weighting these potential stressors with species‐specific vulnerabilities, Humboldt (Spheniscus humboldti), African (Spheniscus demersus), and Chinstrap penguin (Pygoscelis antarcticus) emerge as the species under the most pressure. Our approach explicitly differentiates between climate and human stressors, since the more achievable management of local anthropogenic stressors (e.g., fisheries and land‐based threats) may provide a suitable means for facilitating cumulative impacts on penguins, especially where they may remain resilient to global processes such as climate change. Moreover, our study highlights some poorly represented species such as the Northern Rockhopper (Eudyptes moseleyi), Snares (Eudyptes robustus), and Erect‐crested penguin (Eudyptes sclateri) that need internationally coordinated efforts for data acquisition and data sharing to understand their spatial distribution properly. [ABSTRACT FROM AUTHOR]

The inter-dataset agreement of trends in subweekly near-surface (850 hPa) temperature variability over Southern Hemisphere midlatitude land masses is assessed among 12 global atmospheric reanalysis datasets. A comparison of the climatological temperature variance and dominant sources and sinks of the variance reveals that, except for NCEP-NCAR (R1) and NCEP-DOE (R2), there is a relatively good agreement for their magnitudes and spatial distributions during the satellite era (1980–2022), which indicates that the key features of subweekly variability are sufficiently well represented. A good agreement is noted for the positive trends found in subweekly variability over the satellite era affecting South Africa in September–October–November (SON) and South America in December–January–February (DJF). Although there is agreement in most of the reanalyses concerning the positive trend affecting Australia in SON, this has not yet emerged from the noise associated with interannual variability when considering only the satellite era. It is significant, however, when the period is extended (1954–2022) or limited to the most recent decades (1990–2022). The trends are explained primarily by a more efficient generation of subweekly temperature variance by horizontal temperature advection. This generation is also identified as a source of biases among the datasets. The trends are found to be reproduced even in those reanalyses that do not assimilate satellite data (JRA-55C) or that assimilate surface observations only (ERA-20C, 20CRv2c, and 20CRv3). [ABSTRACT FROM AUTHOR]

There is a close correlation between sunspot number and sunspot area. Through the distribution of sunspot number and area size, we could note significantly disagreements for the two hemispheres. The paper concentrates on the relationship for the northern, the southern hemispheres and the global, and we propose a new method from segmentation regression for description the relationship between the sunspot number and sunspot area of different hemispheres and the global. By the sunspot number, we divide up the data into three parts, the low, the medium, and the high. The results indicate that the segmentation regression method could better describe the relation between sunspot area and number, in particular at the lower solar activity part and the higher part. We could obtain a better regression result for these parts, data more or less static, and data more discrete. Moreover, sunspot area and number behave very differently relationship for the north, the south and the global. In addition, the sunspot number being equal, the sunspot area of the south is usually greater than the north. [ABSTRACT FROM AUTHOR]

Baleen whales (mysticetes) include the largest animals on the Earth. How they achieved such gigantic sizes remains debated, with previous research focusing primarily on when mysticetes became large, rather than where. Here, we describe an edentulous baleen whale fossil (21.12–16.39 mega annum (Ma)) from South Australia. With an estimated body length of 9 m, it is the largest mysticete from the Early Miocene. Analysing body size through time shows that ancient baleen whales from the Southern Hemisphere were larger than their northern counterparts. This pattern seemingly persists for much of the Cenozoic, even though southern specimens contribute only 19% to the global mysticete fossil record. Our findings contrast with previous ideas of a single abrupt shift towards larger size during the Plio-Pleistocene, which we here interpret as a glacially driven Northern Hemisphere phenomenon. Our results highlight the importance of incorporating Southern Hemisphere fossils into macroevolutionary patterns, especially in light of the high productivity of Southern Ocean environments. [ABSTRACT FROM AUTHOR]

The causes of historical changes in the Southern Hemisphere (SH) monsoon are less understood than the Northern Hemisphere (NH) counterpart. Unlike the decline in the NH monsoon during 1901–2014, we found that the SH land monsoon precipitation significantly increased during 1901–2014 in observation, reanalysis, and most historical simulations from phase 6 of the Coupled Model Intercomparison Project (CMIP6). The observed increase in SH land monsoon precipitation is dominated by the Australian and South American monsoons. Moisture budget analysis suggests that half of the wettening is attributable to the strengthening of monsoon circulation, and only one-fifth is caused by atmospheric moistening. The SH monsoon circulation change is mainly affected by the sea surface temperature (SST) gradient between the Indo-Pacific and the eastern Pacific. It enhances the tropical zonal circulation that redistributes the moisture from tropical oceans to land monsoon regions by strengthening the lower-tropospheric convergence and convection. The CMIP6 models, which successfully reproduced the SST contrast between the Indo-Pacific and eastern Pacific, simulate the wettening of the SH monsoon during the historical period; otherwise, the SH monsoon is weakened. In a meridional sense, reanalysis and CMIP6 simulations both demonstrated that the strengthening of SH monsoon convection plays a vital role in the long-term change of zonal mean Hadley circulation, albeit the monsoon band only accounts for 1/3 of the global longitudinal area. Results from this study are useful for constraining the future projection of SH monsoon and understanding the long-term change of Hadley circulation. [ABSTRACT FROM AUTHOR]

The 10–20-day quasi-biweekly oscillation (QBWO) is active in the southwestern Indian Ocean (SWIO) during austral summer. Compared with comprehensive analyses of the QBWO in the Asian monsoon regions during boreal summer, studies focusing on the austral summer QBWO in the SWIO are relatively scarce. In this study, the diversity of the austral summer QBWO in the SWIO is examined based on K-means cluster analysis, which objectively classifies two distinct modes: an eastward-propagating mode (EM) and a poleward-propagating mode (PM). For the EM (PM), an active convection center originates from the subtropical ocean (tropical ocean) and exhibits an eastward (poleward) propagation path. Moisture budget analysis reveals that positive moisture time tendency anomalies show a phase-leading relationship relative to both QBWO convection centers. This phase leading in moisture tendency anomalies is mainly due to horizontal moisture advection. Further analysis demonstrates that meridional moisture transport (i.e., the summer mean moisture advected by the meridional quasi-biweekly wind) is fundamentally responsible for moisture phase leading in both QBWO modes in their mature phases. The combined scale interaction among low frequency, quasi-biweekly, and high frequency contributes to the initial movement for both modes in the growing phases. Although the two modes in the SWIO are initiated in different regions and exhibit distinct evolutionary features, they are regulated by similar moisture dynamics: the northerlies (northeasterlies) of the cyclonic wind response bring higher mean moisture levels east (south) of the convective center, which leads to the eastward (southward) movement of the EM (PM). Significance Statement: The quasi-biweekly oscillation (QBWO), which can affect extreme weather events, such as extreme precipitation and heat waves, is active in the southwestern Indian Ocean (SWIO) during austral summer. Compared with previous studies of the QBWO in the Asian monsoon regions during boreal summer, studies focusing on the austral summer QBWO in the SWIO are relatively scarce. Specifically, we objectively classify the austral summer QBWO in the SWIO into two distinct modes: an eastward-propagating mode (EM) and a poleward-propagating mode (PM). Through moisture tendency diagnosis, we find that the two QBWO modes are regulated by similar moisture dynamics, although they are initiated in different regions and exhibit distinct evolutionary features. This improved understanding may provide insights into the monitoring and prediction of the QBWO. [ABSTRACT FROM AUTHOR]

The relationship between the seasonal Antarctic sea ice concentration (SIC) variability and the extratropical southern Indian Ocean (SIO) sea surface temperature (SST) is explored in this study. It is found that the Antarctic SIC in a wide band of the SIO, Ross Sea, and Weddell Sea is significantly related to an SIO dipole (SIOD) SST anomaly on the interannual time scale during austral spring. This relationship is linearly independent of the effects of El Niño–Southern Oscillation, the Indian Ocean dipole, and the Southern Hemisphere annular mode. The positive phase of the SIOD, with warm SST anomalies off of western Australia and cold SST anomalies centered around 60°E in high latitudes, stimulates a downstream wave train that induces large-scale cyclonic circulations over the SIO and the Ross and Weddell Seas. Subsequently, anomalous horizontal moisture advection causes water vapor divergence, changes the surface energy budget, and cools the underlying ocean, which leads to the increased SIC over the region in the SIO, Ross Sea, and Weddell Sea. This SIOD SST anomaly reached a record low during the austral spring of 2016 and promoted the prominent wave pattern at high latitudes, contributing to the dramatic decline of sea ice in the 2016 spring. In addition, the proportion of the SIC trend that is linearly congruent with the SIOD SST trend during austral spring is quantified. The results indicate that the trend in the SIOD SST may account for a significant component of the 1979–2014 SIC trend in the Ross Sea with the congruency peaking at 60%. [ABSTRACT FROM AUTHOR]

Abstract Subseasonal‐to‐seasonal (S2S) prediction has gained momentum in the recent past as a need for predictions between the weather forecasting timescale and seasonal timescale exists. The availability of S2S databases makes prediction and predictability studies possible over all the regions of the globe. Most S2S studies are, however, relevant to the northern hemisphere. In this review, the S2S literature relevant to the southern hemisphere (SH) are presented. Predictive skill, sources of predictability, and the application of S2S predictions are discussed. Indications from the subseasonal predictability studies for the SH regions suggest that predictive skill is limited to 2 weeks in general, particularly for temperature and rainfall, which are the variables most frequently investigated. However, temperature has enhanced skill compared to rainfall. More S2S prediction studies that include the quantification of the sources of predictability and the identification of windows of opportunity need to be conducted for the SH, particularly for the southern African region. The African continent is vulnerable to weather‐ and climate‐related disasters, and S2S forecasts can assist in alleviating the risk of such disasters.

Using NCEP–NCAR reanalysis data, the atmospheric intraseasonal oscillation (ISO) over the mid-high latitudes in the Southern Hemisphere during austral summer is studied. Two types of 10–30-day eastward- and westward-propagating ISO at mid-high latitudes are extracted by extended empirical orthogonal functions. The analysis of wave activity flux reveals that the energy sources of the eastward-propagating wave train are in the southwest Pacific and southern Indian Ocean, and the westward-propagating wave train is over the east coast of South America. The diagnosis of geopotential height tendency shows that the zonal gradient of ISO relative vorticity guided by mean zonal wind plays a major role in the eastward propagation of the wave train, while the meridional gradient of mean relative vorticity and geostrophic vorticity guided by ISO meridional wind plays a major role in the westward propagation of the wave train. Energy analysis shows that the amplitude enhancement over the South Pacific is due to the ISO disturbance gaining energy from the mean flow. The eastward-propagating ISO obtains energy from the mean flow through kinetic and potential energy conversion, while the westward-propagating ISO cannot obtain energy through potential energy conversion. The surface air temperature and precipitation in South America are affected by the circulation and propagation corresponding to both types of ISO. The useful forecasting skills by the subseasonal-to-seasonal forecasting project for eastward- and westward-propagating types can reach to 17 days, while the potential forecasting skills improve to 20 and 19 days, respectively. Significance Statement: The intraseasonal oscillation (ISO) has important effects on regional weather and climate, and we focus on the ISO over mid-high latitudes in the Southern Hemisphere, which has been paid little attention. We reveal two leading types of the mid-high-latitude ISO during austral summer, namely, the eastward- and westward-propagating types. Also, the characteristics and effects of the two types are explored. To understand their dynamical process, the geopotential height tendency and energy conversion are diagnosed. It is also found that the two ISO types can be predicted up to 17 days in advance by the subseasonal-to-seasonal project, which may provide guidance for the extended-range forecasts. [ABSTRACT FROM AUTHOR]

The skill of subseasonal (multiweek) forecasts of tropical cyclone (TC) occurrence over the Southern Hemisphere is examined in the Australian Bureau of Meteorology's (BoM) multiweek to seasonal prediction system, ACCESS-S2. Relative to its predecessor, ACCESS-S1, ACCESS-S2 shows improved biases in spatial TC frequency in the South Pacific and Southwest Indian Ocean. However, there is no improvement to the known negative bias in TC frequency off the coast of NW Australia. The ability of ACCESS-S2 to provide probabilistic forecasts of TC occurrence for the Southern Hemisphere on multiweek timescales is examined using reliability measures and Brier skill scores. For the period November-February 1990-2012, both ACCESS-S1 and ACCESS-S2 show positive skill relative to climatology for calibrated forecasts out to week 5. However, the skill of ACCESS-S2 is slightly reduced compared to ACCESS-S1 at all lead times, which may be due to the fewer number of ensemble members available. For the full ACCESS-S2 hindcast period, November-April 1981-2018, ACCESS-S2 again shows positive skill of calibrated forecasts over climatology out to week 5. For weeks 1-2, skill is reduced compared to the shorter 1990-2012 period; whereas it is marginally improved for longer lead times (weeks 3-5). Use of lagged ensembles, an alternative linear regression calibration, as well as removing weaker model TCs were examined to potentially improve the skill of ACCESS-S2 forecasts; however, none of these methods were able to significantly increase skill at all lead times. Continued use of the original calibration method is therefore recommended in order to retain skill and continuity of service of the BoM operational and public multiweek TC forecasts. [ABSTRACT FROM AUTHOR]

We investigated reproductive behavior and sexual patterns in two odacid fish—Rainbow cale Heteroscarus acroptilus and Herring cale Olisthops cyanomelas—inhabiting temperate reefs in Australia on the basis of underwater observations and histological studies. The males of both species established a territory and continuously courted females they encountered in the territory. The males and females went up in the water column to release gametes in pairs. We found ovarian cavities in the gonadal tissue of H. acroptilus males, suggesting that protogynous sex change occurred in this species. Dichromatism is reported in O. cyanomelas, with males having a dark blue body color while females have a brown body color; however, we found small mature males also included among brown individuals. Furthermore, we diagnosed O. cyanomelas with gonochorism, which is rare in closely related labrids. We compared the similarities and differences in reproductive behavior and sexual patterns between the two species and with labrids. [ABSTRACT FROM AUTHOR]

The boreal summer intraseasonal oscillation (BSISO) features more distinctive and complex propagation characteristics than its wintertime counterpart, the Madden–Julian oscillation (MJO). While the relationship between the MJO and the Arctic stratosphere during boreal winter has been widely documented, the linkage between the BSISO and the Antarctic stratosphere during austral winter has not been extensively discussed. Here, after identifying the Southern Hemisphere (SH) stratospheric polar vortex warming (SPVW) events, we reveal the bidirectional connection between BSISO and SPVW. Before onset of the SPVW events, the occurrence frequency and amplitude of BSISO phase 5 (P5) shows a significant increase. The most significant responses of the SH polar stratospheric temperature to the BSISO are found about 10 days after BSISO P5. Thus, to some extent, BSISO P5 can be regarded as a precursor to the SH SPVW event, which is attributed to the enhanced upward propagation and dissipation of planetary waves in the SH stratosphere induced by the BSISO P5. After onset of the SPVW events, a significant increase in the occurrence and amplitude of BSISO P6 is observed, corresponding to the enhanced convection over the South China Sea and southern Philippine Sea. Tropical upwelling associated with the strengthened Brewer–Dobson circulation (BDC) induced by the SPVW tends to result in unstable circumstances in the tropical upper troposphere. Then the high correlation between static stability at 150 hPa and outgoing longwave radiation (OLR) anomalies over the South China Sea and southern Philippine Sea provides robust evidence that the intensity of convective activity in the tropics can indeed be modulated by the variability in SH stratospheric polar vortex. Significance Statement: The relationship between the boreal summer intraseasonal oscillation (BSISO) and the Southern Hemisphere (SH) polar stratosphere remains unclear. After selecting the stratospheric polar vortex warming (SPVW) events, we reveal the two-way connection between BSISO and SPVW. Before the SPVW, the significant increase in occurrence and amplitude of BSISO phase 5 (P5) suggests that BSISO P5 can be regarded as a precursor to the weakened polar vortex. After the SPVW, the significant increase in occurrence and amplitude of BSISO phase 6 (P6) establishes that environmental alteration in tropical upper troposphere induced by the SPVW provides a favorable condition for the growth of ensuing convective activity. The results here help us better understand the potential link between stratospheric polar vortex and tropical intraseasonal oscillation. [ABSTRACT FROM AUTHOR]

The recently developed average latitudinal displacement (ALD) methodology is applied to assess the waviness of the austral-winter subtropical and polar jets using three different reanalysis data sets. As in the wintertime Northern Hemisphere, both jets in the Southern Hemisphere have become systematically wavier over the time series and the waviness of each jet evolves quite independently of the other during most cold seasons. Also, like its Northern Hemisphere equivalent, the Southern Hemisphere polar jet exhibits no trend in speed (though it is notably slower), while its poleward shift is statistically significant. In contrast to its Northern Hemisphere counterpart, the austral subtropical jet has undergone both a systematic increase in speed and a statistically significant poleward migration. Composite differences between the waviest and least wavy seasons for each species suggest that the Southern Hemisphere's lower-stratospheric polar vortex is negatively impacted by unusually wavy tropopause-level jets of either species. These results are considered in the context of trends in the Southern Annular Mode as well as the findings of other related studies. [ABSTRACT FROM AUTHOR]

Evaluations of vaccine effectiveness during the March– September Southern Hemisphere influenza season can provide valuable information for countries currently experiencing the influenza season and preceding the October–May Northern Hemisphere influenza season. Since 2013, multiple countries have participated in the Network for the Evaluation of Vaccine Effectiveness in Latin America and the Caribbean–influenza (la Red para la Evaluación de Vacunas en Latino América y el Caribe—influenza [REVELAC–i]) to estimate and monitor vaccine effectiveness (VE) in preventing severe acute respiratory infection (SARI)–associated hospitalization. Based on data contributed by Argentina, Brazil, Chile, Paraguay, and Uruguay on 2,780 SARI patients hospitalized during March 27–July 9, 2023, the adjusted VE against SARI hospitalization associated with any influenza virus during the 2023 Southern Hemisphere season was 51.9% (95% Confidence Interval [CI] 39.2%– 62.0%), including 55.2% (95% CI: 41.8%–65.5%) against the predominating A(H1N1)pdm09. These early, interim estimates, provided before the expected end of seasonal influenza virus circulation, suggest that vaccination substantially reduced the risk for severe influenza illnesses, underscoring the benefits of influenza vaccination. In anticipation of Northern Hemisphere influenza virus circulation, the World Health Organization and CDC recommend that health authorities encourage health care providers to administer annual influenza vaccination to all eligible persons, particularly emphasizing the importance of vaccination for persons at increased risk for severe outcomes (e.g., very young children, persons with preexisting health conditions [including pregnant women], and older adults). [ABSTRACT FROM AUTHOR]

There is still a high diversity of lichen-forming fungi that remains undescribed, especially cryptic lineages at the species level. Integrating morphological, chemical, and DNA sequence data has proved useful in corroborating species descriptions and delimitations. Here we reviewed morphological features, secondary metabolites and the DNA sequences of ITS, mtSSU and nuLSU markers to study the diversity of Xanthoparmelia in southern Africa. A total of 37 species were recorded. Three of these appear undescribed, and we therefore describe them here as new: Xanthoparmelia nimisii , with a sorediate thallus and broad lobes, is well supported as a clade separate from X. annexa ; X. pseudochalybaeizans with a white medulla is phylogenetically distinct from the otherwise similar X. chalybaeizans ; and X. sipmaniana , well supported as a separate clade from the similar X. hypoprocetrarica. In addition, the separation of Xanthoparmelia capensis and X. tinctina requires further studies. [ABSTRACT FROM AUTHOR]