UCL open environment最新文献

Over the past decade or so, many large cities around the world have made little to no progress in lowering ground-level ozone concentrations, despite significant reductions in key precursor pollutants directly emitted into the atmosphere. Ozone comes from complex chemical reactions in the air that make it difficult to control. Current control measures implemented in some cities have apparently reached their limit. While stricter emission regulations, improvements in technology and cleaner fuels have prevented a return to previous ozone levels, they have not reduced them further. They have triggered changes in the mixture of precursor species (i.e., nitrogen oxides and volatile organic compounds) due to differences in the extent to which their emissions have been reduced, emerging emission sources and the increasing relevance of emissions previously overlooked, such as those related to cooking and the use of household cleaning and personal care products. Similarly, as the contribution of typical emission sources (e.g., combustion of fossil fuels) has decreased, biogenic contributions have become more important, as well as the influence of regional and transboundary pollution. These changes have also responded to increasing urbanisation in the face of a changing climate that favours ozone production. There is no recipe that all cities can follow to tackle ambient ozone; however, it is necessary to review why ozone concentrations have not decreased in some cities and what they are doing about it in order to use it as a reference to update, improve and develop control measures tailored to local conditions, as actions implemented in one city may be ineffective or impractical in another. In such a context, this article examines the cases of three metropolitan areas: the Mexico City Metropolitan Area, the Los Angeles Basin and the Beijing-Tianjin-Hebei (Jing-Jin-Ji) region. These urban conglomerations, with different geography, meteorology, socioeconomic conditions and governance, have succeeded in reducing concentrations of many regulated pollutants to levels near or below air quality standards set to protect public health, but not for ozone. While these cities have robust and timely air quality management (i.e., air quality monitoring, emission inventories and air quality models), the current ozone challenge requires even greater efforts to understand the physical and chemical processes at the local and regional scales. This will enable informed actions that can adjust to changing environmental, social and economic scenarios, following a science-policy approach with a perspective of human rights and social justice.

The Global South-Global North divide is widely defined using the Brandt Line, which proposed a geographical divide between more developed countries in the North and less developed countries in the South. Inequities in South-North research collaborations manifest in different ways and at different stages. Many researchers engaged in energy and development research are involved in collaborative projects with research partners across the divide. To ensure success, these collaborations must be inclusive and balanced. Researchers and multilateral organisations are starting to take notice of the potential negative impacts of unbalanced research collaborations. Critical assessments of these imbalances are scarce and there is a knowledge gap of ways to create more inclusive environments that allow researchers from the Global South to contribute solutions for challenges in their local contexts. Through workshops and a survey of researchers engaged in energy and development research, this paper attempts to partially fill this gap by investigating the challenges in collaborative projects faced by researchers in the Global South and Global North. The main findings show significant differences in the research experience of the two groups of researchers with respect to administrative burdens, access to resources, research roles and communication. We present several recommendations for how to address the inequities in collaborative research projects.

This paper investigates the application of nudge theory to reduce utility consumption within student accommodation, specifically focusing on the effectiveness of informational and competition-based nudges. With the pressing challenge of climate change and the significant contribution of the building sector to global energy use, finding innovative, cost-effective strategies to promote sustainable behaviour is critical. This study employs a quasi-experimental design across six buildings divided into four groups: Control, Information-only, Competition Without Prizes and Competition With Prizes. The research aims to explore the differential effects of informational feedback and competition, with and without prizes, on energy consumption. The study utilises a longitudinal approach, examining energy usage across multiple years to control for external factors such as occupancy fluctuations and seasonal effects. Results reveal that the informational nudge, contrary to expectations, increased energy consumption in certain accommodation, possibly due to rebound effects or moral licensing. Meanwhile, the competition without prizes nudge effectively reduced energy usage, highlighting the power of intrinsic motivation and social comparison. However, the competition with prizes nudge showed no significant effect, suggesting that extrinsic rewards might undermine the intrinsic motivation to save energy. This research contributes to the growing body of literature on behavioural change interventions in residential settings, particularly within transient and dense environments such as student accommodation. The findings underscore the need for nuanced, well-designed nudges that account for behavioural dynamics and suggest that low-cost strategies which utilise intrinsic motivators may be more effective than those that provide extrinsic rewards in fostering sustainable habits in student accommodation. Furthermore, the study highlights the importance of robust communication strategies to enhance the efficacy of behavioural interventions in reducing energy consumption.

Xerophilic fungi can proliferate in dry conditions and have been detected in cultural heritage sites and libraries. To protect the staff from fungal exposure and ensure the preservation of heritage collections, research must be focused on improving detection protocols for xerophilic fungi. Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry provides a strong method for the identification of fungi; however, this is dependent on the reference database. The aim of this study was to investigate whether it is possible to develop a supplementary matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry database of xerophilic/xerotolerant Aspergillus species. The database is intended to complement the current Bruker library; for this 19 Aspergillus species grown in four different broth media were included. The database was evaluated on samples from domestic homes, a museum and a warehouse. It was possible to create a database with mass spectra from the 19 species. For some species, it was possible to generate mass spectra from the four tested broth media, while other species required specific media and extended incubation time. Isolates from environmental samples identified by the Bruker fungi library were not misidentified by the supplementary database while some previously unidentified isolates (Aspergillus conicus, Aspergillus domesticus, Aspergillus glabribes and Aspergillus pseudogracilis) could be identified. Using low water-activity agar media had a profound effect on detection of these xerophilic/xerotolerant Aspergillus species. This work shows that it is possible to develop a supplementary matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry database for the identification of xerophilic/xerotolerant Aspergillus species, and that low-water activity broth media are recommended for the construction of a database and the following application.

This paper presents findings from a large-scale survey of 2429 students in Years 7-9 (ages 11-14) in England, exploring their experiences and expectations of climate change and sustainability education. The study reveals that while most students learn about climate change and sustainability in school, primarily through geography and science lessons, there is a desire for a more comprehensive and engaging approach. Students express a strong interest in learning about the future impacts of climate change, practical solutions and global perspectives. They emphasise the importance of outdoor learning, hands-on activities and opportunities for meaningful participation in school and community initiatives. The findings highlight the need for climate change and sustainability education to be embedded across the school curriculum, to provide opportunities for outdoor learning, and to nurture student agency. Explored within a framework of children's rights to education and wellbeing and respective inequalities, this research provides valuable insights for stakeholders seeking to improve climate change and sustainability education and empower young people to address the climate and environmental crisis.

Research on flood vulnerability has mainly focussed on social, economic and human vulnerability and the few studies that have attempted to analyse the physical vulnerability of buildings to natural hazards (seismicity and floods) have been done at the subnational spatial scale resulting in generalised vulnerability outcomes. Additionally, most of the studies used models to analyse vulnerability which are known for uncertainties in the results. This study investigated the physical vulnerability of buildings to flooding in low-income settlements of Biwi and Kawale 1 in Malawi's capital city, Lilongwe. Statistical Package for the Social Sciences 20 was used for descriptive statistics frequency, cross-tabulation and chi-square analysis to correlate exposure factors and the physical vulnerability of buildings. The study found that exposure factors variably influenced the physical vulnerability of individual building types, and that building typology and floodwater depth were important factors. Irrespective of their location, buildings constructed using fired bricks with cement mortar walls and cement floors had low vulnerability while buildings constructed using fired bricks in mud mortar walls and cement floors had high vulnerability. Buildings with protective measures such as high foundations had low vulnerability. The chi-square correlation test showed that the physical vulnerability was influenced by building typologies and floodwater level with a significance value of 0.001 (p < 0.001) and 0.004 (p < 0.005), respectively. Rather than urban planners and disaster management officials emphasising stream reserves as a preventive measure, advocating for the construction of buildings using flood-resistant materials and with high enough foundations in flood-prone areas should be considered central to urban flood risk reduction. Flood vulnerability studies should be conducted in other flood-prone cities of Malawi to support effective citywide urban planning and disaster risk management.

With the increasing public legislation aimed at reducing plastic pollution, compostable plastics have emerged as an alternative to conventional plastics for some food packaging and food service items. However, the true value of compostable plastics can only be realised if they do not enter the environment as contaminants but instead are processed along with food waste using industrial composting facilities. Distinguishing compostable plastics from other plastics in this waste stream is an outstanding problem. Currently, near-infrared technology is widely used to identify polymers, but it falls short in distinguishing plastics contaminated with food waste. This study investigates the application of hyperspectral imaging to address this challenge, enhancing the detection and sorting of contaminated compostable plastics. By combining hyperspectral imaging with various machine learning algorithms we show it is possible to accurately identify and classify plastic packaging with food waste contamination, achieving up to 99% accuracy. The study also measures the impact of plastic features such as darkness, size and level of contamination on model performance, with darkness having the most significant impact. The developed machine learning model can detect plastic with higher levels of contamination more accurately compared to our previous study. Implementing hyperspectral imaging in waste management systems can significantly increase composting and recycling rates, and improve the quality of recycled products. This advanced approach supports the circular economy by ensuring that both compostable and recyclable plastics are effectively processed and recycled, minimising environmental impact.

With a wide range of stoves and appliances available in the ever-evolving Kenyan cooking market, it is important to understand which options are the most cost, time and energy efficient to use. This information can help households to make more informed decisions about their energy use and policy makers to better understand which solutions to promote. Despite its importance, the existing literature offers scant evidence to guide optimal stove and fuel choices. In this research, we utilised controlled cooking tests to investigate the fuel required to cook six regularly prepared dishes on 10 prevalent stove and fuel combinations (including liquified petroleum gas, ethanol, charcoal, kerosene and electric appliances). We also tested the efficiency improvements from pre-soaking beans and using stovetop pressure cookers. We collected primary fuel cost data from across Nairobi in June 2023 and collated historical fuel prices from secondary sources spanning 2019-2023. The prices of liquified petroleum gas, charcoal and kerosene varied considerably by variables such as brand and location, whereas ethanol and on-grid electricity were more stable. The electric pressure cooker was the most cost- and energy-efficient device. For liquified petroleum gas and charcoal, combining pre-soaking beans with a pressure cooker substantially reduced fuel consumption, but was still costlier than the electric pressure cooker. The longitudinal comparison highlighted the dynamic nature of fuel prices in Kenya and how a household's cost-optimal cooking stack can change at short notice. These findings demonstrate how comparative affordability varies both temporally and spatially and can be heavily affected by wider market and policy incentives.

Formally, state parties are equal in all United Nations negotiations. In theory, every state, regardless of its size, economic or political power, has the same opportunities and rights to participate. Nevertheless, United Nations negotiations, such as those on climate, are often considered highly unequal in practice. Many states struggle to meaningfully engage in complex and highly technical multilateral negotiations, including because their delegations are smaller. Here we examine delegation size in United Nations climate negotiations through a procedural justice lens. Starting from normative principles of procedural justice, we argue that equitable negotiations demand the capability of all parties to send a sufficient number of delegates - around 15. Using descriptive analysis of data on delegation sizes of recent Conferences of the Parties, we then highlight that many parties in practice send smaller delegations. Based on these results, we suggest two routes for making climate negotiations more equitable: (i) providing additional resources to poor states to increase their delegation size; and (ii) trimming the overall negotiation agenda to lower the sufficiency threshold.