Global Environmental Change最新文献

Objective

To explore the health effect of anomalous precipitation on deaths among children younger than 5 years (under-5 deaths) in low- and middle-income countries (LMICs).

Methods

Based on a sample of 1.6 million children from 56 LMICs, we conducted a sibling-matched Cox regression model to examine the association between under-5 deaths and anomalous precipitation in annual average. We established a nonlinear exposure–response function to characterize heterogeneity in the association, and checked its robustness by conducting a few sensitivity analyses. To illustrate absolute risks embedded in the complex climate-health linkage, across 100 LMICs, we calculated burden of under-5 deaths attributable to anomalous precipitation, and showed how the burden varied with the El Niño–Southern Oscillation (ENSO), a well-known predictable climate pattern affecting the rainfall cycle. We focused on the intertemporal inequality in the attributable burden.

Results

The epidemiological analyses showed a robust negative association between anomalous precipitation and under-5 deaths for arid areas, and a potentially positive association for humid areas. The anomalous precipitation was significantly associated to an intertemporal inequality in under-5 mortality. Across the 100 LMICs, 26.7% or 134 million under-5 children lived in ENSO-sensitive areas. Among them, anomalous rainfall decreased under-5 deaths by 46,246 (CI: 24,599–68,703) during an El Niño year (October 2015 to September 2016), and increased under-5 deaths by 77,505 (CI: 55,890–99,815) during a La Niña year (March 2008 to February 2009) across the 100 LMICs.

Conclusion

Anomalous precipitation can lead to intertemporal inequality in child health. Healthcare resources should be allocated according to predicted variability in precipitation, such as ENSO-mediated extreme rainfall.

Urgent action to tackle the climate crisis will only be possible with significant public support for radical lifestyle change. Arguments that seek to delay climate action and justify inadequate mitigation efforts, often termed ‘discourses of delay’, are widespread within political and media debate on climate change. Here we report the results of novel public deliberation and visioning workshops, conducted across the UK in 2020/2021 to explore visions of a 1.5 °C future. We found that despite very strong public support for many low-carbon lifestyle strategies in principle, entrenched discourses of delay are limiting beliefs that a fair, low-carbon future is possible. Consisting of four overarching narratives of climate inaction (Resisting personal responsibility; Rejecting the need for urgency; Believing change is impossible; and Defending the social contract), this public discourse of delay is characterised by three distinct repertoires (each with its own emotional resonance), that act to weaken support for climate action by producing defensive responses to discussions of low-carbon lifestyle change and undermining public sense of agency. We argue that countering these narratives, and the defensive responses they invoke, is essential for achieving meaningful public action on climate change.

A spatially explicit (0.5 degree resolution) analysis is presented of the impact of human lifestyle, diet and nutrient use efficiency in food production and wastewater treatment on exceedance of threshold concentrations for nitrate in groundwater, and total N and total P concentrations in surface water, as well as criteria for their ratio. This analysis starts from the middle-of-the-road (SSP2) and the sustainability (SSP1) Shared Socio-economic Pathways (SSP), focusing on the year 2050. The scenarios with changed lifestyle assume a reduction of food wastage and a low-meat diet for all world inhabitants, implying large reductions of meat and milk consumption and production in industrialized countries. Scenarios with improved nutrient use efficiencies assume maximum achievable efficiencies under practical conditions. The SSP2 scenario combined with assumptions on lifestyle and human diet leads to improvement in industrialized countries only, and increased levels in many other regions. A strong improvement is achieved in SSP1, but not in many developing countries, and SSP1 combined with changed lifestyle leads to improvement of groundwater and surface water quality in industrialized countries only. Therefore, changed lifestyle needs to be combined with efforts to improve the efficiency in food production systems and wastewater treatment to achieve reductions of the area affected by groundwater contamination and eutrophication of surface waters. Reduction strategies need to find a balance between N and P, since it is easier to reduce N in rivers to levels below the threshold than P.

Although it is widely recognized that migration is socially transformative, the potential contributions of migrants to transformations towards sustainability in their destination areas are often overlooked in mainstream discourse on environmentalism and sustainability. Here we seek to identify current narratives of migrants and sustainability across individual, urban, and national scales. Migrants are commonly framed in public policy as having no or even negative impacts on sustainability. The study hypotheses that the lived experience of sustainability by migrants within urban destinations differ from dominant discourses and perceptions of migrant populations within societies. We test and document such divergence using data from 21 interviews with key stakeholders from the city and Swedish national level, an attitudinal survey of 895 migrants and non-migrants in Malmö, Sweden; and a media analysis of local and national Swedish newspapers. Survey results show that migrants engage more extensively with a number of sustainability actions compared to non-migrants culminating in new insights on ‘migrants as sustainability actors’. By contrasting individual scale practices against urban to national sustainability narratives, the study illuminates current barriers to and the potential of migrants to play a transformative role in progress towards sustainability that is unrecognized in dominant policy discourses. To tap into this potential, the study emphasizes that sustainability policy across scales should embrace plurality and migration as fundamental parts of progress towards sustainability.

Many human-introduced alien species economically impact industries worldwide. Management prioritisation and coordination efforts towards biological invasions are hampered by a lack of comprehensive quantification of costs to key economic sectors. Here, we quantify and estimate global invasion costs to seven major sectors and unravel the introduction pathways of species causing these costs — focusing mainly on primary economic sectors: agriculture, fisheries and forestry. From 1970 to 2020, costs reported in the InvaCost database as pertaining to Agriculture, Fisheries, and Forestry totaled $509 bn, $1.3 bn, and $134 bn, respectively (in 2017 United States dollars). Pathways of costly species were diverse, arising predominantly from cultural and agricultural activities, through unintentional contaminants with trade, and often impacted different sectors than those for which species were initially introduced. Costs to Agriculture were pervasive and greatest in at least 37 % (n = 46/123) of the countries assessed, with the United States accumulating the greatest costs for primary sectors ($365 bn), followed by China ($101 bn), and Australia ($36 bn). We further identified 19 countries highly economically reliant on Agriculture, Fisheries, and Forestry that are experiencing massive economic impacts from biological invasions, especially in the Global South. Based on an extrapolation to fill cost data gaps, we estimated total global costs ranging from at least $517–1,400 bn for Agriculture, $5.7–6.5 bn for Fisheries, and $142–768 bn for Forestry, evidencing substantial underreporting in the Forestry sector in particular. Burgeoning global invasion costs challenge sustainable development and highlight the need for improved management action to reduce future impacts on industry.

Significance

With rapidly rising biological invasion rates, efficient management is critical for economic and environmental impact mitigation. Specifically, improved quantification of the economic cost of biological invasions to the world’s primary economic sectors could provide crucial information for policymakers who must prioritise actions to limit ongoing and future impacts. We show that since 1970, over $600 bn in impacts has been incurred across Agriculture, Fisheries and Forestry, with the largest share reported in Agriculture. We further identify 19 countries, which rely heavily on primary sectors, facing comparatively high impacts from invasions, requiring urgent action. However, gaps in cost reporting across invasive taxa and countries suggest that these impacts are grossly underestimated. Proactive prioritisation by policymakers is needed to mitigate future impacts to primary sectors.

A rapid and full decarbonisation of both energy and industry is essential to meet the targets in the Paris agreement, which brings coal- and carbon-intensive regions under significant pressure. Some regions have advanced in their transition and can provide insights in the system change processes. In this paper, we investigate the socio-economic transition processes of Essen and Duisburg as part of the wider structural change in the Ruhr Region/ Germany. We explore causes and effects of their trajectories in the last 30 + years and identify differences in outcome as a function of the interventions and/or contextual differences, while investigating whether either city crossed a tipping point in their transition process (yet). Therefore, we specifically evaluate the cities’ development trajectories by seeking evidence for “no”, “incremental” or “radical or tipping” changes in sets of qualitative and quantitative indicators.

Our analysis shows that both cities experienced incremental changes in their demographic, economic and political trajectories but we found no evidence for either city to have crossed a tipping point in their transition process yet. However, distinct developments in the cities’ policy narratives and visions indicate qualitative changes while putting them on different development trajectories potentially leading to tipping points in the future. Our study shows that the sequence of interventions and timing are important factors for the trajectory of a region determining the quality of societal change. It also suggests that radical change and tipping are the exception rather than the rule, especially in the highly complex social systems of cities.

The number of voluntary interventions seeking to generate carbon offsets by reducing deforestation and forest degradation, generally known as REDD+ projects, has increased significantly over the past decade. Offsets are issued based on project performance in comparison to a baseline scenario representing the expected deforestation in a project area in the absence of REDD+. Baselines from most ongoing REDD+ projects were established following four methodologies approved by the largest voluntary carbon offset certification scheme worldwide, the Verified Carbon Standard (VCS) from Verra. These methodologies often rely on oversimplified assumptions about deforestation that remain overlooked by project developers, certification bodies, and buyers. Here, we explore what these methodological assumptions are and their implications. We then construct alternative deforestation baselines for four ongoing VCS-certified projects using the four VCS-REDD+ methodologies and examine how they differ. Overall, we observe large discrepancies among the project baselines. On average, the highest baseline value we calculate for each project is more than 14 times greater than the lowest value across the four projects studied. This illustrates the lack of robustness and consistency across the VCS-REDD+ methodologies. The results also call into question the additionality of carbon offsets issued based on these methodologies. New baseline methods need to be urgently developed if voluntary REDD+ projects are to reliably estimate their additional contribution to climate change mitigation. The incorporation of causal inference methods represents current best practices in measuring the efficacy of REDD+ interventions. Regrettably, these methods remain largely overlooked by project developers, certification standards, and governmental and international bodies. Dynamic baselines developed by independent analysts could potentially enable project developers to distinguish the impacts of the REDD+ intervention from confounding factors and properly estimate additionality.

Latin American cities are increasingly impacted by floods and this trend is likely to be further exacerbated under the combined effects of climate change and urbanisation. To reduce urban flood risk, green infrastructure and the ability to preserve and rehabilitate green spaces is often mentioned as an option to improve the hydraulic response of cities. Yet, little empirical evidence exists about the degree to which a greener city land cover can reduce the impacts of extreme rainfall on urban economic activity. Using earth observations from 630 cities across Latin America, this paper shows that extreme rainfall has a negative impact on urban economic activity, as proxied by cities’ night lights. Importantly, it finds that this negative impact diminishes as city’s land cover becomes greener: for cities where dense vegetation represents more than 20 % of total city area, the marginal impact of extreme rainfall is broadly halved vis-a-vis cities below this threshold. A counterfactual analysis for the year 2015 suggests that increasing the greenness of 25 % of the cities in our sample could have reduced losses by US$ 6,500 million -equivalent to a 19 % reduction of total estimated losses. These results evidence the benefits that a greener city land cover that makes room for green infrastructure can provide to adapt to more erratic rainfall patterns.

Byproduct metals are essential to global low carbon transition since they are irreplaceable in modern renewable energy technologies. Gallium (Ga) is classified as one critical byproduct metal due to its extensive use in electronic applications and low carbon technologies, as well as its limited resource endowment. It is urgent to uncover the global and regional Ga stocks and flows so that the potential supply risks can be mitigated. This study maps the global and regional Ga cycles for the period of 2000–2020 by employing a trade-linked multiregional material flow analysis (MFA) method. Our results show that 79% of the global Ga co-mined from bauxite ended up in red mud or entered the aluminum cycle as an impurity, indicating a significant recycling potential. Different involved regions have different but complementary roles in the global Ga supply chain. China dominates the global primary Ga production, accounting for 97% of the global total in 2020. Japan and the United States are key players in high-purity Ga refining and rely on Ga to support their electronic devices manufacturing. Unfortunately, Ga recycling practices are still not occurring due to the low Ga concentrations in major applications. Since the global demand for Ga will continue to grow in the near future, it is urgent to initiate collaborative efforts so that Ga recycling can be enhanced. These efforts are critical to ensure the sustainable Ga supply and facilitate the global transition toward low carbon development.

Current agricultural practices in Europe are increasingly aggravating societal and environmental safety concerns. This creates social and regulatory pressures on farmers, which can lead to declining material and social status of farmers, farmer discontent, and anti-regulation protests. These tensions are rooted in conflicting value systems for agricultural development, which can range from productivist pathways (i.e. valuing production above all else) to increasing multifunctionality pathways (i.e. valuing agriculture for its contribution to multiple economic, environmental and societal needs). It is largely unknown to what degree individual farms and agricultural landscapes are transitioning towards increasing productivism or multifunctionality in practice. Here, we mapped landscape changes and interviewed farmers (n = 274) to examine the diversity of agricultural development pathways in 17 study sites across Europe over the last 20 years (2000–2020). We also assessed the associations between the development pathways and farmers’ perceptions of socio-economic outcomes, namely job satisfaction, societal valuation, and economic performance. Farm-level development was largely aligned with productivist pathways, while landscape-level changes aligned more closely with an increasing multifunctionality pathway. Farmers on pathways of increasing multifunctionality did not perceive improved outcomes on livelihood indicators as compared to productivist farmers. Furthermore, farms on increasing multifunctionality pathways were concentrated in sites with very high management intensities that face strong pressure from environmental regulations, as well as low-intensity, mountainous sites, where opportunities for intensification are limited. These results suggest that current pathways that increase multifunctionality arise mostly by necessity. Successful agricultural transformation will therefore require policy to create enabling environments that provide socioeconomic benefits for farmers to increase multifunctionality, and a civil society and market conditions that value sustainable agriculture.