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The Global Fire Assimilation System (GFASv1.0) calculates biomass burning emissions by assimilating Fire Radiative Power (FRP) observations from the MODIS instruments onboard the Terra and Aqua satellites. It corrects for gaps in the observations, which are mostly due to cloud cover, and filters spurious FRP observations of volcanoes, gas flares and other industrial activity. The combustion rate is subsequently calculated with land cover-specific conversion factors. Emission factors for 40 gas-phase and aerosol trace species have been compiled from a literature survey. The corresponding daily emissions have been calculated on a global 0.5° × 0.5° grid from 2003 to the present. General consistency with the Global Fire Emission Database version 3.1 (GFED3.1) within its accuracy is achieved while maintaining the advantages of an FRP-based approach: GFASv1.0 makes use of the quantitative information on the combustion rate that is contained in the observations, and it detects fires in real time at high spatial and temporal resolution. GFASv1.0 indicates omission errors in GFED3.1 due to undetected small fires. It also exhibits slightly longer fire seasons in South America and North Africa and a slightly shorter fire season in Southeast Asia. GFASv1.0 has already been used for atmospheric reactive gas simulations in an independent study, which found good agreement with atmospheric observations. We have performed simulations of the atmospheric aerosol distribution with and without the assimilation of MODIS aerosol optical depth (AOD). They indicate that the emissions of particulate matter need to be boosted with a factor of 2–4 to reproduce the global distribution of organic matter and black carbon. This discrepancy is also evident in the comparison of previously published top-down and bottom-up estimates. For the time being, a global enhancement of the particulate matter emissions by 3.4 is recommended. Validation with independent AOD and PM₁₀ observations recorded during the Russian fires in summer 2010 show that the global Monitoring Atmospheric Composition and Change (MACC) aerosol model with GFASv1.0 aerosol emissions captures the smoke plume evolution well when organic matter and black carbon are enhanced by the recommended factor. In conjunction with the assimilation of MODIS AOD, the use of GFASv1.0 with enhanced emission factors quantitatively improves the forecast of the aerosol load near the surface sufficiently to allow air quality warnings with a lead time of up to four days

We explore the implications of online social endorsement for the Covid-19 vaccination program in the United Kingdom. Vaccine hesitancy is a long-standing problem, but it has assumed great urgency due to the pandemic. By early 2021, the United Kingdom had the world’s highest Covid-19 mortality per million of population. Our survey of a nationally representative sample of UK adults ( N = 5,114) measured socio-demographics, social and political attitudes, media diet for getting news about Covid-19, and intention to use social media and personal messaging apps to encourage or discourage vaccination against Covid-19. Cluster analysis identified six distinct media diet groups: news avoiders, mainstream/official news samplers, super seekers, omnivores, the social media dependent, and the TV dependent. We assessed whether these media diets, together with key attitudes, including Covid-19 vaccine hesitancy, conspiracy mentality, and the news-finds-me attitude (meaning giving less priority to active monitoring of news and relying more on one’s online networks of friends for information), predict the intention to encourage or discourage vaccination. Overall, super-seeker and omnivorous media diets are more likely than other media diets to be associated with the online encouragement of vaccination. Combinations of (a) news avoidance and high levels of the news-finds-me attitude and (b) social media dependence and high levels of conspiracy mentality are most likely to be associated with online discouragement of vaccination. In the direct statistical model, a TV-dependent media diet is more likely to be associated with online discouragement of vaccination, but the moderation model shows that a TV-dependent diet most strongly attenuates the relationship between vaccine hesitancy and discouraging vaccination. Our findings support public health communication based on four main methods. First, direct contact, through the post, workplace, or community structures, and through phone counseling via local health services, could reach the news avoiders. Second, TV public information advertisements should point to authoritative information sources, such as National Health Service (NHS) and other public health websites, which should then feature clear and simple ways for people to share material among their online social networks. Third, informative social media campaigns will provide super seekers with good resources to share, while also encouraging the social media dependent to browse away from social media platforms and visit reliable and authoritative online sources. Fourth, social media companies should expand and intensify their removal of vaccine disinformation and anti-vax accounts, and such efforts should be monitored by well-resourced, independent organizations.

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This article describes a new capability for high-precision 14 C measurement of CO 2 from air at the Rafter Radiocarbon Laboratory, GNS Science, New Zealand. We evaluate the short-term within-wheel repeatability and long-term between-wheel repeatability from measurements of multiple aliquots of control materials sourced from whole air. Samples are typically measured to 650,000 14 C counts, providing a nominal accelerator mass spectrometry (AMS) statistical uncertainty of 1.3‰. No additional uncertainty is required to explain the within-wheel variability. An additional uncertainty factor is needed to explain the long-term repeatability spanning multiple measurement wheels, bringing the overall repeatability to 1.8‰, comparable to other laboratories measuring air materials to high precision. This additional uncertainty factor appears to be due to variability in the measured 14 C content of OxI primary standard targets, likely from the combustion process. We observe an offset of 1.4‰ in our samples relative to those measured by the University of Colorado INSTAAR, comparable to interlaboratory offsets observed in recent intercomparison exercises.

Incidental exposure to shared news on Facebook is a vital but understudied aspect of how citizens get involved with politics. This experiment investigates the influence of recommender characteristics (tie strength, political knowledge, political similarity) and different media sources (tabloids, legacy, and digital-born outlets) including multiple mediators(e.g., social pressure, outlet credibility) on incidental exposure to political news on Facebook. A 3 × 3 multi-stimulus, between-subject Experiment with two additional quasi-factors and 135 different stimuli was conducted using a representative sample (N = 507). Results showed that strong ties and recommenders with high knowledge increase news exposure, but the impact of knowledge is limited to recommenders with similar political opinions. Similar effects occur for different media types, which also have an independent impact on news exposure. Structural equation modeling reveals that media source effects are mediated through media perceptions, whereas recommender effects work via the desire for social monitoring and perceived issue importance.

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Editors note: For easy download the posted pdf of the State of the Climate for 2014 is a very low-resolution file. A high-resolution copy of the report is available by clicking here. Please be patient as it may take a few minutes for the high-resolution file to download.