Search

The Australian Bureau of Meteorology (BoM) has recently operationalized a post-processing suite called ConvParams, which computes a wide array of convective parameters using output from the BoM’s global deterministic and ensemble NWP models. Outputs from the suite include parcel parameters such as CAPE and CIN (computed for a range of different initial parcels), kinematic diagnostics such as bulk wind difference and storm-relative helicity (computed for a range of different atmospheric layers), and composite indices such as the supercell composite parameter and significant tornado parameter. In addition, the suite also identifies important features in the atmospheric profile such as capping inversions and elevated mixed layers. A unique feature of ConvParams, compared to other similar codebases (NSHARP/SHARPpy, MetPy) is its use of high-order polynomials to approximate pseudoadiabatic processes, which permits parcel calculations that are both fast and highly accurate. Significant computational advantages also come from the use of an ahead-of-time compiler (Pythran), which “transpiles” the native Python code into fast C++ code. As well as being used in operations, ConvParams is being run as part of the second-generation BoM Atmospheric Regional Reanalysis for Australia (BARRA2), a regional downscaling of the ERA5 reanalysis, and the BoM Atmospheric Regional Projections for Australia (BARPA), a regional downscaling of CMIP6 climate projections. Once complete, these simulations will provide the most comprehensive picture of historical and future convective environments in Australia to date, supporting major research in this space over the coming years. This presentation will provide an overview of the ConvParams suite and highlight its applications in both operational forecasting and future research endeavours.

Operational guidance for thunderstorms and severe convective hazards at the Australian Bureau of Meteorology has undergone a major uplift in recent years, with the introduction of new NWP models, post-processing systems, and convection diagnostics. The latest guidance is based on the third generation of the Australian Community Climate and Earth-System Simulator (ACCESS) suite, which includes global and convection-allowing models run in both deterministic and ensemble configurations. In this presentation, we will introduce the ACCESS suite and discuss three sources of convective guidance based on its outputs. The first is the new ConvParams post-processing suite, which ingests model-level data from the ACCESS Global and Global Ensemble models and computes a wide array of convective parameters for use in ingredients-based forecasting of thunderstorms and associated hazards. The second is the Bureau’s lightning prediction system, Calibrated Thunder, which combines ACCESS Global Ensemble forecasts and recent lightning observations to produce calibrated probabilistic forecasts of lightning within a 10-km radius across Australia and surrounding coastal waters. The third comprises storm attributes from the ACCESS City and City Ensemble models, including simulated reflectivities, updraft helicity, and parameterised lightning flash rates. For the ensemble, these diagnostics are post-processed to obtain the ensemble maximum and neighbourhood-maximum ensemble probabilities (NMEPs), and interrogated using a variety of novel visualisation strategies. Our presentation will provide an overview of each of these guidance streams, describe how they are used in operations, and assess their strengths and limitations. We will also highlight promising avenues for future developments.

Proximity soundings have long been used to explore how the vertical structure of temperature, humidity, and winds influence convective storms and their associated hazards. In severe thunderstorm research and forecasting, convective parameters are often used to summarize certain characteristics of the sounding. While extremely useful, these parameters are unable to describe the rich complexity that is readily apparent in hodographs and skew T–logp diagrams. Motivated by a desire to retain more of these details, the present study uses self-organizing maps (SOMs) to group soundings based on their full vertical structure. The analysis makes use of a sample of more than 10 000 model proximity soundings for right-moving supercells associated with tornadoes and significant severe hail and straight-line winds in the contiguous United States (CONUS). Separate SOMs are developed for the wind and thermodynamic profiles, each with 3 × 3 nodes, resulting in a set of nine hodographs and nine skew T–logp diagrams that broadly represent the spectrum of near-storm environments for significant severe right-moving supercells in the CONUS. Both SOMs are shown to provide a good representation of the variability in key convective parameters, although, for the thermodynamic SOM, variations in LCL heights and midlevel lapse rates are somewhat limited. Based on the soundings assigned to them, the SOM nodes are characterized in terms of their associated hazards, their relationship with storm mode and mesocyclone strength, and their spatial and temporal variability. Potential applications of the SOMs in severe weather forecasting and idealized numerical simulations are also highlighted.

During 2013, multiple tornadoes occurred across Australia, leading to 147 injuries and considerable damage. This prompted speculation as to the frequency of these events in Australia, and whether 2013 constituted a record year. Leveraging media reports, public accounts, and the Bureau of Meteorology observational record, 69 tornadoes were identified for the year in comparison to the official count of 37 events. This identified set and the existing historical record were used to establish that, in terms of spatial distribution, 2013 was not abnormal relative to the existing climatology, but numerically exceeded any year in the bureau’s record. Evaluation of the environments in which these tornadoes formed illustrated that these conditions included tornado environments found elsewhere globally, but generally had a stronger dependence on shear magnitude than direction, and lower lifting condensation levels. Relative to local environment climatology, 2013 was also not anomalous. These results illustrate a range of tornadoes associated with cool season, tropical cyclone, east coast low, supercell tornado, and low shear/storm merger environments. Using this baseline, the spatial climatology from 1980 to 2019 as derived from the nonconditional frequency of favorable significant tornado parameter environments for the year is used to highlight that observations are likely an underestimation. Applying the results, discussion is made of the need to expand observing practices, climatology, forecasting guidelines for operational prediction, and improve the warning system. This highlights a need to ensure that the general public is appropriately informed of the tornado hazard in Australia, and provide them with the understanding to respond accordingly.

National meteorological and hydrological services provide severe weather warning information to inform decision-making by emergency management organisations. Such information also helps communities to take defensive and mitigating actions prior to and during severe weather events. Globally, warning information issued by meteorological and hydrological services varies widely. This can range from solely hazard-based to impact-based forecasting encompassing the exposure and vulnerability of communities to severe weather. The most advanced of these systems explicitly and quantitatively model the impacts of hazards on affected assets or infrastructure such as vehicle traffic or housing. Incorporating impact information into severe weather warnings contextualises and personalises the warning information, increasing the likelihood that individuals and communities will take preparatory action. However, providing useful and detailed impact information remains a challenge. This paper reviews a selection of current severe weather warnings and impact forecasting capabilities globally and highlights uncertainties that limit the forecasting and modelling of multi-hazard events.

This paper reports on the status of a comprehensive ten-year research and development effort toward hybrid system-in-foil (HySiF). In HySiF, the merits of high-performance integrated circuits on ultra-thin chips and of large-area and discrete electronic component implementation are combined in a complementary fashion in and on a flexible carrier substrate. HySiF paves the way to entirely new applications of electronic products where form factor, form adaptivity and form flexibility are key enablers. In this review paper the various aspects of thin-chip fabrication and embedding, device and circuit design under impact of unknown or variable mechanical stress, and the on- and off-chip implementation of sensor, actuator, microwave, and energy supply components are addressed.

Insights into oncogenesis derived from cancer susceptibility loci (SNP) hold the potential to facilitate better cancer management and treatment through precision oncology. However, therapeutic insights have thus far been limited by our current lack of understanding regarding both interactions of these loci with somatic cancer driver mutations and their influence on tumorigenesis. For example, although both germline and somatic genetic variation to the p53 tumor suppressor pathway are known to promote tumorigenesis, little is known about the extent to which such variants cooperate to alter pathway activity. Here we hypothesize that cancer risk-associated germline variants interact with somatic TP53 mutational status to modify cancer risk, progression, and response to therapy. Focusing on a cancer risk SNP (rs78378222) with a well-documented ability to directly influence p53 activity as well as integration of germline datasets relating to cancer susceptibility with tumor data capturing somatically-acquired genetic variation provided supportive evidence for this hypothesis. Integration of germline and somatic genetic data enabled identification of a novel entry point for therapeutic manipulation of p53 activities. A cluster of cancer risk SNPs resulted in increased expression of prosurvival p53 target gene KITLG and attenuation of p53-mediated responses to genotoxic therapies, which were reversed by pharmacologic inhibition of the prosurvival c-KIT signal. Together, our results offer evidence of how cancer susceptibility SNPs can interact with cancer driver genes to affect cancer progression and identify novel combinatorial therapies. Significance: These results offer evidence of how cancer susceptibility SNPs can interact with cancer driver genes to affect cancer progression and present novel therapeutic targets.

The central east coast of Australia is frequently impacted by large hail and damaging winds associated with severe convective storms, with individual events recording damages exceeding AUD 1 billion. These storms present a significant challenge for forecasting because of their development in seemingly marginal environments. They often have been observed to intensify upon approaching the coast, with case studies and climatological analyses indicating that interactions with the sea breeze are key to this process. The relative importance of the additional lifting and vorticity along the sea-breeze front in comparison with the change to a cooler, moister air mass with stronger low-level shear behind the front has yet to be investigated. Here, the role of the sea-breeze air mass is isolated using idealized numerical simulations of storms developing in a horizontally homogeneous environment. The base-state substitution (BSS) modeling technique is utilized to introduce the sea-breeze air mass following initial storm development. Relative to a simulation without BSS, the storm is longer lived and more intense, ultimately developing supercell characteristics including increased updraft rotation, deviant motion to the left of the mean wind vector, and a strong reflectivity gradient on the inflow edge. Separately simulating the changes in the thermodynamic and wind fields reveals that the enhanced storm longevity and intensity are primarily due to the latter. The change in the low-level environmental winds slows gust-front propagation, allowing the storm to continue to ingest warm, potentially buoyant environmental air. At the same time, increased low-level shear promotes the development of persistent updraft rotation that causes the storm to make a transition from a multicell to a supercell.

In this paper, a rigorous methodology for extracting the thermal compact model parameters of packaged chips is presented. The methodology is based on using a custom-designed test chip with multiple heating and temperature sensing elements in order to predict the temperature distribution in packaged chips after packaging. The technique involves measurement of various chips with different thicknesses, different packages, and for different power dissipation scenarios through which the thermal model parameters can be extracted. The results show that ultrathin chips with a total thickness below $20~\mu \text{m}$ experience a dramatically increased temperature for localized heat dissipation. In addition to this, the measurements conducted in time domain and frequency domain show that at high enough frequencies of heat pulsing, the temperature variations become independent of the thermal boundary conditions of the chip. The measurement results are compared to the finite-element method simulation data. The simulations together with the measurement methodology serve as a technique to extract the thermal compact model parameters of packaged chips after being fabricated and packaged in an accurate and efficient way.

This paper presents the design, fabrication and characterization of digital logic gates, flip-flops and shift registers based on low-voltage organic thin-film transistors (TFTs) on flexible plastic substrates. The organic transistors are based on the p-channel organic semiconductor dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT) and have channel lengths as short as 5 μ m and gate-to-contact overlaps of 20 μ m. The organic TFT is modeled which allows us to simulate different logic gate architectures prior to the fabrication process. In this study, the zero-VGS, biased-load and pseudo-CMOS logic families are investigated, where their static and dynamic operations are modeled and measured. The inverter and NAND gates use channel length of 5 μ m and operate with a supply voltage of 3 V. Static and dynamic master-slave flip-flops based on biased-load and pseudo-CMOS logic are designed, fabricated and characterized. A new design for biased-load dynamic flip-flops is proposed, where transmission gate switches are implemented using only p-channel transistors. 1-stage shift registers based on the new design and fabricated using TFTs with a channel length of 20 μ m operate with a maximum frequency of about 3 kHz.