19 research outputs found

    Global fire emissions buffered by the production of pyrogenic carbon

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    Landscape fires burn 3–5 million km2 of the Earth’s surface annually. They emit 2.2 Pg of carbon per year to the atmosphere, but also convert a significant fraction of the burned vegetation biomass into pyrogenic carbon. Pyrogenic carbon can be stored in terrestrial and marine pools for centuries to millennia and therefore its production can be considered a mechanism for long-term carbon sequestration. Pyrogenic carbon stocks and dynamics are not considered in global carbon cycle models, which leads to systematic errors in carbon accounting. Here we present a comprehensive dataset of pyrogenic carbon production factors from field and experimental fires and merge this with the Global Fire Emissions Database to quantify the global pyrogenic carbon production flux. We found that 256 (uncertainty range: 196–340) Tg of biomass carbon was converted annually into pyrogenic carbon between 1997 and 2016. Our central estimate equates to 12% of the annual carbon emitted globally by landscape fires, which indicates that their emissions are buffered by pyrogenic carbon production. We further estimate that cumulative pyrogenic carbon production is 60 Pg since 1750, or 33–40% of the global biomass carbon lost through land use change in this period. Our results demonstrate that pyrogenic carbon production by landscape fires could be a significant, but overlooked, sink for atmospheric CO2

    False Beliefs About Asylum Seekers to Australia: The Role of Confidence in Such Beliefs, Prejudice, and the Third Person Effect

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    There has been much controversy about the treatment of asylum seekers in Australia in recent years, with the Australian Government continuing to enforce a very hard-line stance on asylum seekers who arrive to Australia by boat. The present study examined attitudes towards asylum seekers using 164 Australian community members during June 2015 by way of questionnaire. Our primary research question involved how five variables predicted false beliefs about asylum seekers. Specifically, we measured prejudice, the third-person effect, and confidence in the answers given to false beliefs about asylum seekers. Regression results indicated that the main predictors of false beliefs were right-wing political orientation, prejudice, confidence in espousing false beliefs, and the third-person effect (politicians). Furthermore, most of our community participants accepted a large number of false beliefs as being true, with approximately two-thirds of our participants scoring above the midpoint. This reflects similar findings over the last decade or so. Our results indicate that, if one believes in bottom-up change, a more nuanced approach needs to be undertaken with community anti-prejudice interventions

    The Molecular Identification of Organic Compounds in the Atmosphere: State of the Art and Challenges

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    Fluorescent organosilica micro- and nanoparticles with controllable size

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    This paper reports on the synthesis of uniformly dye-doped organosilica particles with narrow size distribution. The particle size can be controlled from tenths of nanometers up to several micrometers, whilst still maintaining monodispersity. Microparticles were observed to swell in various solvents up to ∼2.5 times their original volume, suggesting the presence of a gel-like internal structure. As shown by confocal microscopy, this morphological control of particle swelling has important implications for the encoding of the nano/micro particles with organic dyes, such as rhodamine B isothiocyanate. Swelling allows the dye to penetrate the organosilica matrix and produce uniformly dye-doped nano- and microparticles. Finally, we suggest a coagulation model for the particle formation which significantly differs from conventional Stöber synthesis

    A tunable high-pass filter for simple and inexpensive size-segregation of sub-10-nm nanoparticles

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    Recent advanced in the fields of nanotechnology and atmospheric sciences underline the increasing need for sizing sub-10-nm aerosol particles in a simple yet efficient way. In this article, we develop, experimentally test and model the performance of a High-Pass Electrical Mobility Filter (HP-EMF) that can be used for sizing nanoparticles suspended in gaseous media. Experimental measurements of the penetration of nanoparticles having diameters down to ca 1nm through the HP-EMF are compared with predictions by an analytic, a semi-empirical and a numerical model. The results show that the HPEMF effectively filters nanoparticles below a threshold diameter with an extremely high level of sizing performance, while it is easier to use compared to existing nanoparticle sizing techniques through design simplifications. What is more, the HP-EMF is an inexpensive and compact tool, making it an enabling technology for a variety of applications ranging from nanomaterial synthesis to distributed monitoring of atmospheric nanoparticles.ChemE/Materials for Energy Conversion & Storag

    Facial and Vocal Cues in Perceptions of Trustworthiness

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    Abstract. The goal of the present research was to study the relative role of facial and acoustic cues in the formation of trustworthiness impressions. Furthermore, we investigated the relationship between perceived trustworthiness and perceivers ’ confidence in their judgments. 25 young adults watched a number of short clips in which the video and audio channel were digitally aligned to form five different combinations of actors’ face and voice trustworthiness levels (neutral face + neutral voice, neutral face + trustworthy voice, neutral face + non-trustworthy voice, trustworthy face + neutral voice, and non-trustworthy face + neutral voice). Participants provided subjective ratings of the trustworthiness of the actor in each video, and indicated their level of confidence in each of those ratings. Results revealed a main effect of face-voice channel combination on trustworthiness ratings, and no significant effect of channel combination on confidence ratings. We conclude that there is a clear superiority effect of facial over acoustic cues in the formation of trustworthiness impressions, propose a method for future investigation of the judgment-confidence link, and outline the practical implications of the experiment.

    Can We Make a Difference? Prejudice Towards Asylum Seekers in Australia and the Effectiveness of Antiprejudice Interventions

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    Over the past few decades, Australia has implemented increasingly restrictive measures to try and deter the arrival of asylum seekers. In our article, we review what is known in the literature about the antecedents of prejudice against asylum seekers. We outline 11 mechanisms, or variables, as being particularly important. We then draw out the practical implications as they relate to antiprejudice interventions. Within the research and implications, we discuss our own experiences of working directly with asylum seekers over the past decade and in running antiprejudice interventions. We conclude that even though the situation is bleak in Australia at the time of writing this article (at the end of 2014), we must continue with attempts to combat the demonisation of asylum seekers both on an individual level and a structural level
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