Every day around 93% of children under the age of 15 (1.8 billion children) breathe outdoor air that is so polluted it puts their health and development at serious risk. Due to the pandemic, however, ventilation of buildings using outdoor air has become an important safety technique to prevent the spread of COVID-19. With the mounting ev-idence suggesting that air pollution is impactful to human health and educational out-comes, this contradictory guidance may be problematic in schools with higher air pol-lution levels, but keeping kids COVID-19 free and in school to receive their education is now more pressing than ever. To understand if all schools in an urban area are ex-posed to similar outdoor air quality and if school infrastructure protects children equally indoors, we installed research grade sensors to observe PM2.5 concentrations in indoor and outdoor settings to understand how unequal exposure to indoor and out-door air pollution impacts indoor air quality among high- and low-income schools in Salt Lake City, Utah. Based on this approach, we found that during atmospheric inver-sions and dust events, there was a lag ranging between 35 to 73 minutes for the out-door PM2.5 concentrations to follow a similar temporal pattern as the indoor PM2.5. This lag has policy and health implications and may help to explain the rising concerns re-garding reduced educational outcomes related to air pollution in urban areas. These data and resulting analysis show that poor air quality may impact school settings, and the potential implications with respect to environmental inequality.

Abstract Smoke plume dynamic science focuses on understanding the various smoke processes that control the movement and mixing of smoke. A current challenge facing this research is providing timely and accurate smoke information for the increasing area burned by wildfires in the western USA. This chapter synthesizes smoke plume research from the past decade to evaluate the current state of science and identify future research needs. Major advances have been achieved in measurements and modeling of smoke plume rise, dispersion, transport, and superfog; interactions with fire, atmosphere, and canopy; and applications to smoke management. The biggest remaining gaps are the lack of high-resolution coupled fire, smoke, and atmospheric modeling systems, and simultaneous measurements of these components. The science of smoke plume dynamics is likely to improve through development and implementation of: improved observational capabilities and computational power; new approaches and tools for data integration; varied levels of observations, partnerships, and projects focused on field campaigns and operational management; and new efforts to implement fire and stewardship strategies and transition research on smoke dynamics into operational tools. Recent research on a number of key smoke plume dynamics has improved our understanding of coupled smoke modeling systems, modeling tools that use field campaign data, real-time smoke modeling and prediction, and smoke from duff burning. This new research will lead to better predictions of smoke production and transport, including the influence of a warmer climate on smoke.

ABSTRACT We examined evolutionary pathways for water quality policies in relation to changing pollution events and socio-political system changes in Oregon, USA, and South Korea. Despite geographic and temporal differences, strong oversight and financial support of the governments with public pressure played a crucial role in point source control. As point sources came under control, focus shifted to nonpoint source policies that have evolved through different pathways according to the regional socio-hydrological context. In Oregon, cross-scale collaborative governance and watershed approaches have been encouraged from the beginning. While the South Korean government relied on the rules of the point source era in the early period, it emphasized collaborative and inclusive policies in the later period. The trajectories of both regions illustrate that the pivotal policies in the point source era do not necessarily guarantee successes in nonpoint source management, and hydra-headed problems such as climate change can further complicate water quality management.

Abstract Recovery trajectories from restoration projects are poorly understood, making it difficult to set restoration targets as part of project planning. As part of the Delaware River Watershed Initiative (DRWI), we collected baseline environmental and biological data at 84 sites in watersheds where agricultural Best Management Practices (BMPs) are being implemented and forested land is being preserved. The objective of this study was to understand which diatom and macroinvertebrate community measures best characterize biological integrity along a gradient of land cover, habitat measures, and water chemistry in order to later set targets for recovery. To this end, we ran separate Redundancy Analysis (RDA) ordinations in which environmental variables constrained (1) community metrics and (2) relative abundance (taxonomic composition) for macroinvertebrates and diatoms. To understand where along the environmental gradient the sites were represented differently by the respective biotic community measures (community metrics and taxonomic composition), the two constrained ordinations were then compared using Procrustes distance. For macroinvertebrate communities, we saw the most agreement in site characterization between the ordinations at intermediate % agricultural land, but disagreement at both high and low % agricultural land. For diatom communities, we saw the most agreement between the site characterizations at high to intermediate % agricultural land, with increasing disagreement associated with increasing % forested land cover. Use of baseline data to set targets for ecosystem recovery requires consideration of which data are most relevant for the site conditions and what amount of change is feasible based on project implementation and effectiveness. A key aspect of choosing endpoints is when the loss of information inherent to metrics makes them less useful for accurately evaluating ecological integrity, especially when looking to capture incremental changes. Based on our findings, we suggest the use of some community metrics and some key taxa to set targets of recovery in biotic communities in agricultural streams, and that these targets be adjusted to best fit the ecological conditions at a given site within a larger data set. Accordingly, monitoring must take place in the context of regional conditions and must be designed to inform target‐setting.

Abstract Spread of nonindigenous organisms by shipping is one of the largest threats to coastal ecosystems. Limited monitoring and understanding of this phenomenon currently hinder development of effective prevention policies. Surveying ports in North America, South America, Europe, Southeast Asia, and Australia we explored environmental DNA community profiles evident of ship-born species spread. We found that community similarities between ports increased with the number of ship voyages, particularly if the ports had similar environments, and when indirect stepping-stone connections were considered. We also found 57 known non-indigenous taxa, some in hitherto unreported locations. We demonstrate the usefulness of eDNA-based tools for global biodiversity surveys, and highlight that shipping homogenizes biodiversity in predictable that could inform policy and management.