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The European Centre for Medium range weather forecast (ECMWF) on behalf of the Copernicus Emergency Management Service (CEMS) has recently widened the fire danger data offering in the Climate Data Store (CDS) to include a set of fire danger forecasts with lead times up to 7 months. The dataset incorporates fire danger indices for three different models developed in Canada, United States and Australia. The indices are calculated using ECMWF Seasonal Forecasting System 5 (SEAS5) and verified against the relevant reanalysis of fire danger based on the ECMWF Re-Analysis (ERA5). The data set is made openly available for the period 1981 to 2023 and will be updated regularly providing a resource to assess the predictability of fire weather at the seasonal time scale. The data set complements the availability of seasonal forecast provided by the Copernicus Emergency Management Service in real time. A preliminary analysis shows that globally anomalous conditions for fire weather can be predicted with confidence 1 month ahead. In some regions the prediction can extend to 2 months ahead. In most situations beyond this horizon, forecasts do not show more skill than climatology. However an extended predictability window, up to 6-7 months ahead is possible when anomalous fire weather is the results of large scale phenomena such as the El Niño Southern Oscillation and the Indian Ocean Dipole, often conducive of extensive fire burning in regions such as Indonesia and Australia. [ABSTRACT FROM AUTHOR]

The Pacific Northwest Pyrocumulonimbus Event (PNE) took place in British Columbia during the evening and nighttime hours between 12 and 13 August 2017. Several pyroconvective clouds erupted on this occasion, and released in the upper troposphere and lower stratosphere unprecedented amounts of carbonaceous aerosols (300 ktn). Only a few years later, an even larger pyrocumulonimbus (pyroCb) injection took place over Australia. This event, named "the Australian New Year (ANY) event", injected up to 1100 ktn of aerosol between 29 December 2019 and 4 January 2020. Such large injections of carbonaceous aerosol modify the stratospheric radiative budgets, locally perturbing stratospheric temperatures and winds. In this study, we use the Goddard Earth Observing System Chemistry Climate Model (GEOS CCM) to study the perturbations on the stratospheric meteorology induced by an aerosol injection of the magnitude of the PNE. Our simulations include the radiative interactions of aerosols, so that their impact on temperatures and winds are explicitly simulated. We show how the presence of the carbonaceous aerosols from the pyroCb causes the formation and maintenance of a synoptic-scale stratospheric anticyclone. We follow this disturbance considering the potential vorticity anomaly and the brown carbon aerosol loading and we describe its dynamical and thermodynamical structure and its evolution in time. The analysis presented here shows that the simulated anticyclone undergoes daily expansion–compression cycles governed by the radiative heating, which are directly related to the vertical motion of the plume, and that the aerosol radiative heating is essential in maintaining the anticyclone itself. [ABSTRACT FROM AUTHOR]

The mechanisms of earthquake rupture in lower continental crust, below the usual frictional‐viscous transition, remain uncertain. In addressing this problem, the study of pseudotachylyte (quenched frictional melt produced during seismic fault slip) and related structures from deeply exhumed rocks can provide direct observational constraints. A felsic granulite from the Musgrave Ranges (central Australia) exceptionally preserves pristine microstructures spatially related to a pseudotachylyte. This sample remained dry, without introduction of hydrous fluids, during pseudotachylyte development and subsequent exhumation. It was therefore unaffected by alteration and metamorphic re‐equilibration. Fractures in the damage zone developed asymmetrically to either side of the pseudotachylyte and are marked by new, randomly oriented quartz, feldspar, and garnet grains. Pulverization of garnet occurred locally between intersecting fractures with powder injected into dilatant fractures in a quartz inclusion within the garnet host. Injection of pulverized material can explain the growth of new, compositionally different minerals (quartz, feldspar, kyanite, ilmenite, magnetite, and rutile) along dilatant fractures developed in a short‐lived seismic event. The pseudotachylyte contains only clasts of quartz, suggesting an unusually high melting temperature. The sequentially developed microstructures provide a time‐lapse record of thermomechanical processes during a single earthquake event, including initial rupture propagation with associated off‐fault damage and local pulverization during very dynamic fluctuations in the local stress field; frictional heating and eventual melting during fault slip; flow and injection of melt; and rapid solidification (quenching) and crystallization of new minerals. This occurred under lower continental crustal conditions of ca. 650°C and 1.2 GPa about 550 Myrs ago. Plain Language Summary: Some special rocks (pseudotachylytes: quenched melts produced by frictional heating during seismic slip on a fault) exhumed from deep in the Earth's crust provide the opportunity to study old earthquakes that occurred at depths that are not directly observable. The pseudotachylyte we studied from the Musgrave Ranges in central Australia was formed during a single earthquake some 550 million years ago at depths of ca. 40 km and temperatures of ca. 650°C, but remained remarkably well preserved on its path to the Earth's surface. As a result, the sample preserves a complete time‐lapse record of the sequence of microstructures representative of different thermal and mechanical processes, which lasted only seconds to minutes during a seismic event, including initial fracture propagation, off‐fault damage with local pulverization, and development, flow, and final solidification of frictional melt. Key Points: Time sequence of microstructures related to pseudotachylyte formation in the lower continental crust (Musgrave Ranges, central Australia)Dry conditions with no infiltration of water‐rich fluid before, during, or after seismic rupturing and pseudotachylyte developmentAsymmetric fracturing, local garnet pulverization, and high‐temperature frictional melting represent different stages of a single earthquake rupture [ABSTRACT FROM AUTHOR]

Garnet is a high-strength mineral compared to other common minerals such as quartz and feldspar in the felsic crust. In felsic mylonites, garnet typically occurs as porphyroclasts that mostly evade crystal plastic deformation, except under relatively high-temperature conditions. The microstructure of granulite facies garnet in felsic lower-crustal rocks of the Musgrave Ranges (Central Australia) records both fracturing and crystal plastic deformation. Granulite facies metamorphism at ∼1200 Ma generally dehydrated the rocks and produced millimetre-sized garnets in peraluminous gneisses. A later ∼550 Ma overprint under sub-eclogitic conditions (600–700 ∘ C, 1.1–1.3 GPa) developed mylonitic shear zones and abundant pseudotachylyte, coeval with the neocrystallization of fine-grained, high-calcium garnet. In the mylonites, granulite facies garnet porphyroclasts are enriched in calcium along rims and fractures. However, these rims are locally narrower than otherwise comparable rims along original grain boundaries, indicating the contemporaneous diffusion and fracturing of garnet. The fractured garnets exhibit internal crystal plastic deformation, which coincides with areas of enhanced diffusion, usually along zones of crystal lattice distortion and dislocation walls associated with subgrain rotation recrystallization. The fracturing of garnet under dry lower-crustal conditions, in an otherwise viscously flowing matrix, requires transient high differential stress, most likely related to seismic rupture, consistent with the coeval development of abundant pseudotachylyte. Highlights. Garnet is deformed by fracturing and crystal plasticity under dry lower-crustal conditions. Ca diffusion profiles indicate multiple generations of fracturing. Diffusion is promoted along zones of higher dislocation density. Fracturing indicates transient high-stress (seismic) events in the lower continental crust. [ABSTRACT FROM AUTHOR]

Geophysical evidence for lower continental crustal earthquakes in almost all collisional orogens is in conflict with the widely accepted notion that rocks, under high grade conditions, should flow rather than fracture. Pseudotachylytes are remnants of frictional melts generated during seismic slip and can therefore be used as an indicator of former seismogenic fault zones. The Fregon Subdomain in Central Australia was deformed under dry sub-eclogitic conditions of 600-700 °C and 1.0-1.2 GPa during the intracontinental Petermann Orogeny (ca. 550 Ma) and contains abundant pseudotachylyte. These pseudotachylytes are commonly foliated, recrystallized, and cross-cut by other pseudotachylytes, reflecting repeated generation during ongoing ductile deformation. This interplay is interpreted as evidence for repeated seismic brittle failure and post- to inter-seismic creep under dry lower-crustal conditions. Thermodynamic modelling of the pseudotachylyte bulk composition gives the same PT conditions of shearing as in surrounding mylonites. We conclude that pseudotachylytes in the Fregon Subdomain are a direct analogue of current seismicity in dry lower continental crust. [ABSTRACT FROM AUTHOR]

Every model is, by definition, a simplification of the system under investigation. Although it would be desirable to reduce the gap between the simulated and the observed behaviors of the system to zero, this reduction is generally impossible owing to the unavoidable uncertainties inherent in any modeling procedure. Uncertainty analyses can provide useful insights into the best model approach to be used for obtaining results with a high level of significance and reliability. The evaluation of parameter uncertainties is necessary for calibration and for estimating the impact of these uncertainties on model performance. In this context, the uncertainty of a river water-quality model developed in previous studies is presented. The main goal is to gain insights into the modeling approaches concerning small rivers. Previous works generally focused on modeling the large river while neglecting the small one. Following a model calibration, the model uncertainty has been assessed by means of the generalized likelihood uncertainty estimation (GLUE). The results showed that the biological process related to the biological oxygen demand (BOD) removal influenced mainly by the parameters characterizing deoxygenation and nitrogen removal. On the other hand, the biological processes related to nitrogen removal were influenced not only by the parameters related to the nitrogen removal but also to oxygen concentration. The application of the GLUE methodology shows that the river quality model considered is suitable for simulating the important processes involved. Uncertainty bounds showed different amplitudes with respect to the pollutant species considered. In particular, the oxygen uncertainty bounds were narrower with respect to the other model components suggesting much attention must be paid to both model algorithms and quality data to be gathered. The study confirmed the suitability of the GLUE methodology as a powerful tool as a simplified screening methodology to assess uncertainty. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the risks of coronary heart disease (CHD) and total mortality among adults with subclinical hypothyroidism. The study included 55,287 adults in the U.S., Europe, Australia, Brazil and Japan, who were followed up from 1972 to 2007. Of the total study participants, 3,450 developed subclinical hypothyroidism, while 51,837 had euthyroidism. Study authors found that increased thyroid-stimulating hormone (TSH) concentration increased the risk of CHD and CHD-related mortality. They concluded that patients with subclinical hypothyroidism have higher risk of CHD.

The article presents a study which explores the sex-specific migratory behavior of humpback whales in genetic aspect. The method of the study includes the assessment of the mitochondrial DNA (mtDNA) distribution among 135 sampled humpback whales taking an annual migration from eastern Australia to New Zealand and neighboring coasts. The result of the study shows that female whales prefer to take the shortest route or perpendicular path towards the feeding area, while males which are assumed to come from wide range of population, prefer to take the longest route.

Unlabelled: For many families and their children, the use of complementary/alternative medicine (CAM) is an accepted adjunct or alternative to conventional therapy, even if data available in the literature regarding risks and adverse drug reactions (ADRs) pertaining to childhood populations are scarce. Moreover, despite widespread and increasing use of CAM, there are limited data on how paediatricians communicate with mothers and/or patients about CAM. Therefore, we report the studies available in the literature in the paediatric field and summarise what is known about ADRs and risks of CAM, taking into account in particular problems related to interactions between phytotherapy and conventional medicines and to counselling.Conclusion: from the analysis of the literature, some interesting aspects emerge: (1) the extent of CAM use in the paediatric field is increasingly sought by parents of children with chronic illnesses; (2) most parents who choose CAM medicine for their children believe that these therapies are "natural" and thus "safe" and (3) physicians often feel to know too little about CAM and wish to learn more for different reasons including "to dissuade whether the alternative method is unsafe and/or ineffective". Therefore, paediatricians should be prepared to discuss alternative therapies with parents, since talking about CAM may help to minimise the risks and to restrain parental misconceptions and doubts. Educational interventions for parents should also be performed to bring about a more aware use of traditional and alternative medicines. [ABSTRACT FROM AUTHOR]

The use of Engineered Wood Systems (EWS) as structural alternatives or complements of traditional materials, such as steel and concrete, is of growing interest and acceptance in the architecture, engineering, and construction industries. Gathering evidence from the Australian context, this paper proposes a roadmap for the adoption of EWS as the primary structural materials of medium-rise buildings, with the scope of increasing levels of public awareness about the potential and current shortcomings of these building technologies. A nation-wide survey with stakeholders at the forefront of adoption in structural design, construction, and property development, indicates that the demand for timber in multi-storey projects has promising prospects of growth, but faces circumstantial industry-wide hurdles in the short to medium term. Awareness of benefits and inclination towards more use of timber among designers are positive factors that provide a promising base for further adoption. The translation of positive front-end design attitudes into adoption, however, requires holistic long-term investment efforts with industry-wide education. The pathway to innovation for timber in multi-storey projects needs to grow beyond mere promotional strategies of its benefits, seeking to expand technical knowledge through education and reaching out beyond a group of already committed and knowledgeable stakeholders at the forefront of adoption. [ABSTRACT FROM AUTHOR]

Abstract The over 600 km long Woodroffe Thrust developed at lower to mid-crustal levels during the intracontinental Petermann Orogeny at ca. 560–520 Ma. Ductile deformation with a top-to-north shear sense was accommodated along a shallowly (≤30°) south-dipping surface. Metamorphic conditions during deformation are established along a 60 km N-S transect, providing an ideal framework for studying variation in microstructure and crystallographic preferred orientations with changing temperature (ca. 520–620 °C) and pressure/depth in dominantly dry felsic crust. In the Woodroffe Thrust mylonites, dynamic recrystallization of quartz was dominated by subgrain rotation, whereas feldspar underwent grain size reduction by neocrystallization. Differential stress, estimated from quartz grain size piezometry, decreases with increasing metamorphic grade (i.e., deeper structural levels), and indicates a long-term average strain rate of around 10−11–10−12 s−1. We propose a qualitative rheological model to explain the observed cyclic interplay between ductile shearing (mylonitization) and brittle fracturing (pseudotachylyte formation) in the relatively dry middle crust. The model involves the downward migration of earthquake ruptures from the overlying seismogenic zone, which transiently triggers seismic slip at mid-crustal levels. Highlights • The Woodroffe Thrust involves an interplay between brittle and ductile deformation. • Microstructures are analyzed along a ~60 km section in the direction of thrusting. • Quartz recrystallized mainly by subgrain rotation, feldspar by neocrystallization. • The long-term average strain rate of the Woodroffe Thrust was ca. 10–11–10-12 s-1. • Transient coseismic strain rate increase can trigger earthquakes at mid-crustal levels. [ABSTRACT FROM AUTHOR]

• The first expedition to the depths of the Southern Ocean facing Bremer canyon systems. • First ROV images of these unique deep-sea environments and inhabitants (180 to 3300 m) • Discovery of spectacular 'animal forests' in the Bremer and Hood canyons. • Scleractinian corals found well below the aragonite saturation horizon (>1000 m) • Major fossil coral deposits occur at all three study areas, especially Mount Gabi. Here we present the outcomes of the first deep-sea remotely operated vehicle study of previously unexplored submarine canyon systems along the southwest Australian continental margin. This was conducted around: (1) the Bremer Marine Park; (2) the Mount Gabi seamount and nearby slope-shelf margin at the interface of the Southern and Indian oceans; with new information from (3) the Perth Canyon Marine Park located in the SE Indian Ocean. These canyons differ from many explored around the world in having no connectivity to continental river systems, thus little detrital input, with the Bremer systems and Mount Gabi facing the Southern Ocean which plays a key role in the global ocean circulation and climate systems. Such studies in the vast deep waters around the Australian continent are rare given the lack of local ROV capability available for research, thus little is known about these environments. Using the resources of the Schmidt Ocean Institute, we characterised the submarine topography from high-resolution bathymetric mapping, geology, physical and chemical oceanography, and provide an overview of these environments including the fauna observed and collected. We show that these Southern Ocean-influenced environments incorporate South Indian Central Water, Subantarctic Mode Water, Antarctic Intermediate Water, and Upper and Lower Circumpolar Deep Water, with Antarctic Bottom Water present in deep water just south of the Bremer canyon systems. The richness in megabenthos, especially along the steep, rocky substrates of the canyon heads and walls around the Bremer canyon systems, contrasts to the comparatively depauperate fauna of the more northerly Perth Canyon. Various corals serve as important substrates for a range of other species and often exhibit particular faunal associations. Especially notable are distinct ecological zones including a bryozoan and sponge-dominated (animal) forest on the shelf edge, spectacular coral gardens along canyon margins, and the occurrence of solitary scleractinians well below the aragonite saturation horizon. Subfossil coral deposits were discovered across all three study areas, reflecting periodic waxing and waning of deep-water Scleractinia throughout this southwest region. Extensive pre-modern assemblages at Mount Gabi contrast markedly with the sparse populations of living species and suggest that it might have once been a major coral hotspot, or whether they reflect long-term coral aggregations is yet to be determined. Nevertheless, stark differences in both living and past coral distribution patterns across our study sites point to at least localised fluctuations in Southern Ocean-derived nutrient and/or oxygen supplies to these deep-sea communities. [ABSTRACT FROM AUTHOR]