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[en] Gridded hourly temperature forecasts from the Bureau of Meteorology's Gridded Operational Consensus Forecasting (GOCF) system are combined in real time with the Australian Water Availability Project (AWAP) gridded daily temperature analyses to produce gridded daily maximum and minimum temperature forecasts with lead times from one to five days. These forecasts are compared against the historical record of AWAP daily temperature analyses (1911 to present), to identify regions where record or near-record temperatures are predicted to occur. This paper describes the GOCF/AWAP system, showing how the daily maximum and minimum temperature forecasts are prepared from the hourly forecasts, and how they are bias-corrected in real time using the AWAP analyses, against which they are subsequently verified. Using monthly climatologies of long-term daily mean, standard deviation and all-time highest and lowest on record, derived forecast products (for both maximum and minimum temperature) include ordinary and standardised anomalies, 'forecast - highest on record' and 'forecast - lowest on record'. Compensation for the climatological variation across the country is achieved in these last two products, which provide the necessary guidance as to whether or not record-breaking temperatures are expected, by expressing the forecast departure from the previous record in both 0C and standard deviations.
[en] The prediction of global sea-level rise is one of the major challenges of climate science. While process-based models are still being improved to capture the complexity of the processes involved, semi-empirical models, exploiting the observed connection between global-mean sea level and global temperature and calibrated with data, have been developed as a complementary approach. Here we investigate whether twentieth century sea-level rise could have been predicted with such models given a knowledge of twentieth century global temperature increase. We find that either proxy or early tide gauge data do not hold enough information to constrain the model parameters well. However, in combination, the use of proxy and tide gauge sea-level data up to 1900 AD allows a good prediction of twentieth century sea-level rise, despite this rise being well outside the rates experienced in previous centuries during the calibration period of the model. The 90% confidence range for the linear twentieth century rise predicted by the semi-empirical model is 13–30 cm, whereas the observed interval (using two tide gauge data sets) is 14–26 cm. (letter)
[en] Luminescent polymeric nanoparticles (LPNs) with aggregation-induced emission (AIE) feature have emerged as the most promising candidates for biological imaging owing to their unique AIE feature, great water dispersity, strong fluorescence, low cytotoxicity and biocompatibility. Although numerous successful strategies for construction of AIE-active LPNs have been developed, the preparation of dynamic linkages containing AIE-active LPNs based on multicomponent reactions has been rarely reported. In this work, we report a facile method for the formation of AIE-active LPNs via a one-pot conjugation of PEG-B(OH)2, 1-thioglycerol and AIE-active dye PhE-alc in short time under rather mild reaction conditions (e.g. ambient temperature, air atmosphere, absent of metal catalysts and in the present of water). The successful formation of AIE-active mPEG-PhE LPNs was confirmed by different characterization techniques in details. The great optical and biological properties certified their applicable for biological imaging application. More importantly, the novel method for the formation of AIE-active LPNs is rather simple, high efficiency and atom economy, which greatly enriched their practical biomedical applications. - Graphical abstract: A facile one-pot strategy based on the formation of dynamic bonds has been developed for the fabrication of luminescent polymeric nanoparticles with aggregation-induced emission feature. - Highlights: • Aggregation-induced emission luminescent polymeric nanoparticles • A one-pot multicomponent reaction • AIE-active LPNs containing dynamic linkages • The AIE-active LPNs are promising for biomedical applications.
[en] Single crystal X-ray and synchrotron X-ray powder diffraction have been used to probe the structure of Ba3NaIr2O9 from 300 K down to 20 K. Ba3NaIr2O9 is found to undergo a structural transition from hexagonal symmetry, P63/mmc, at ambient temperature to monoclinic symmetry, C2/c, at low temperature. The evolution of the unit cell volume upon cooling is indicative of a higher order structural transition, and the symmetry breaking becomes apparent as the temperature is decreased. The low temperature monoclinic structure of Ba3NaIr2O9 contains strongly distorted (NaO6) and (IrO6) octahedra in comparison to the room temperature hexagonal structure.
[en] The possibility of limiting the increase of the average earth atmospheric temperature to 2 Celsius degrees appears to belong to the past. Rich countries have succeeded in blocking or even reducing their emissions of greenhouse effect gases but they still rely heavily on fossil energies. As for developing countries their development is essentially based on fossil energies they use in a growing tendency. It is difficult to image how these trends could be reversed in a short time. In the article the carbon budget is defined as the cumulated quantity of carbon that will avoid exceeding a fixed value of temperature. For instance a 2 degrees increase of temperature correspond to a CO_2 concentration in the atmosphere of 450 ppm. In the case where nothing was done and that fossil energies were used until their exhaustion, the carbon budget would reach 657 ppm and the corresponding increase of temperature would be beyond 4 degrees. (A.C.)
[en] In this paper we have exploited the self-imaging or Talbot effect and Moire technique to measure the temperature distribution in the air enclosed between two paral led plates of different temperatures. This study shows that for the plates width of 60 cm a change of 1degC in 1 cm can be easily detected
[en] Most of us have heard or read about global warming. However, the messages we receive are often in conflict, raising more questions than answer. Is global warming a good or a bad thing? has it already started or is it part of our future? Are we, or are we not doing anything about it? Should we be concerned? This primer on Global Warming is designed to clear up some of this confusion by providing basic scientific information on global warming issue. It is clear that there is still much to learn about global warming. However, it is also clear that there is a lot that we already know - and that dose provide cause for concern. We must understand the global warming issue if we are to make wise decisions and take responsible actions in response to the challenges and opportunities posed by global warming. Chapter 1 of 'the primer on global Warming' set the stage with a brief overview of science of global warming within the context of climate change. In addition, it introduces the specific issues that surround the global warming problem. As far as the science of global warming is concerned the following questions are discussed. What is global climate? Is climate change natural? What causes climate to vary on a global scale? How does the composition of the atmosphere relate to climate change. but there are also certain issues discussed here which surround the global warming such as: If climate varies naturally, why is there a concern about 'global warming'? What are the potential consequences of 'global warning'. What human activities contribute to 'global warming'. (Author)
[en] Complete text of publication follows. Oscillatory modes with period of approximately 8 years were detected in monthly time series of geomagnetic activity aa-index, North Atlantic Oscillation index and near-surface air temperature from several mid-latitude European locations. Instantaneous phases of the modes underwent synchronization analysis and their statistically significant phase coherence, beginning from 1950's, has been observed.
[en] The influence of the ambient temperature and the thickness of the paint coating on the magnetic-noise parameters is investigated, in the diagnostics of steel structures. It is shown that nondestructive magnetic-noise diagnostics may be used to monitor the state of load-bearing structural elements in situ at any temperature, in extreme conditions.
[en] The quantum oscillations of population in an asymmetric double quantum dots system coupled to a phonon bath are investigated theoretically. It is shown how the environmental temperature has effect on the system