• Energy Research

The ocean provides resources key to human health and well-being, including food, oxygen, livelihoods, blue spaces, and medicines. The global threat to these resources posed by accelerating ocean acidification is becoming increasingly evident as the world’s oceans absorb carbon dioxide emissions. While ocean acidification was initially perceived as a threat only to the marine realm, here we argue that it is also an emerging human health issue. Specifically, we explore how ocean acidification affects the quantity and quality of resources key to human health and well-being in the context of: (1) malnutrition and poisoning, (2) respiratory issues, (3) mental health impacts, and (4) development of medical resources. We explore mitigation and adaptation management strategies that can be implemented to strengthen the capacity of acidifying oceans to continue providing human health benefits. Importantly, we emphasize that the cost of such actions will be dependent upon the socioeconomic context; specifically, costs will likely be greater for socioeconomically disadvantaged populations, exacerbating the current inequitable distribution of environmental and human health challenges. Given the scale of ocean acidification impacts on human health and well-being, recognizing and researching these complexities may allow the adaptation of management such that not only are the harms to human health reduced but the benefits enhanced.

High ambient heat can directly influence blood pressure (BP) through the vasodilation of the skin vasculature and indirectly by affecting urinary volume and electrolyte levels. We evaluated the direct and urine electrolyte-mediated effects of ambient temperature on BP. We pooled 5,624 person-visit data from a community-based stepped-wedge randomized control trial in southwest coastal Bangladesh from December 2016 to May 2017. Same-day ambient temperature data from local weather stations were linked to participant BP and urine electrolytes using geo-locations of their residential addresses. We implemented causal mediation analyses using the product methods of coefficients with linear mixed models under the sequential ignorability assumption. Separate models were run for each urinary electrolyte mediator (sodium, potassium, calcium, and magnesium), followed by combined models to evaluate the natural direct and electrolyte-mediated indirect effects of temperature on BP. Models had participant-level random intercepts and were adjusted for age, sex, body mass index (BMI), religion, exercise, smoking status, sleep hours, alcohol consumption, urine creatinine, time trend, household assets, drinking water salinity, and seasonality. For the combined mediators (sodium, potassium, calcium, and magnesium), for every 5°C increase in average daily temperature: the direct effect on systolic BP was -1.42 (95 % CI: -1.94, -0.92) mmHg and urine sodium mediated effect was -0.12 (95 % CI: -0.20, -0.05) mmHg; while urine potassium mediated effect was 0.15 (95 % CI: 0.08, 0.25) mmHg; urine calcium-mediated effect 0.06 (95 % CI: 0.01, 0.12) mmHg; and urine magnesium mediated effect -0.00 (95 % CI: -0.03, 0.02) mmHg. We detected similar associations for diastolic BP, pulse pressure, and mean arterial pressure. We found a significant inverse direct effect of ambient temperature on BP compared to minimally mediated urine electrolyte effects. Further studies are needed to uncover the underlying mechanisms of ambient heat and BP associations and to describe the clinical consequences of these associations.

Campylobacteriosis is a major public health concern. The weather factors that influence spatial and seasonal distributions are not fully understood.To investigate the impacts of temperature and rainfall on Campylobacter infections in England and Wales, cases of Campylobacter were linked to local temperature and rainfall at laboratory postcodes in the 30 days before the specimen date. Methods for investigation included a comparative conditional incidence, wavelet, clustering, and time series analyses.The increase of Campylobacter infections in the late spring was significantly linked to temperature two weeks before, with an increase in conditional incidence of 0.175 cases per 100,000 per week for weeks 17 to 24; the relationship to temperature was not linear. Generalized structural time series model revealed that changes in temperature accounted for 33.3% of the expected cases of Campylobacteriosis, with an indication of the direction and relevant temperature range. Wavelet analysis showed a strong annual cycle with additional harmonics at four and six months. Cluster analysis showed three clusters of seasonality with geographic similarities representing metropolitan, rural, and other areas.The association of Campylobacteriosis with temperature is likely to be indirect. High-resolution spatial temporal linkage of weather parameters and cases is important in improving weather associations with infectious diseases. The primary driver of Campylobacter incidence remains to be determined; other avenues, such as insect contamination of chicken flocks through poor biosecurity should be explored.

A healthy ocean is essential for human health, and yet the links between the ocean and human health are often overlooked. By providing new medicines, technologies, energy, foods, recreation, and inspiration, the ocean has the potential to enhance human health and wellbeing. However, climate change, pollution, biodiversity loss, and inequity threaten both ocean and human health. Sustainable realisation of the ocean's health benefits will require overcoming these challenges through equitable partnerships, enforcement of laws and treaties, robust monitoring, and use of metrics that assess both the ocean's natural capital and human wellbeing. Achieving this will require an explicit focus on human rights, equity, sustainability, and social justice. In addition to highlighting the potential unique role of the healthcare sector, we offer science-based recommendations to protect both ocean health and human health, and we highlight the unique potential of the healthcare sector tolead this effort.

The impacts of climate on health and wellbeing occur in time and space and through a range of indirect, complicated mechanisms. This diversity of pathways has major implications for national public health planning and influence on interventions that might help to mitigate and adapt to rapidly changing environmental conditions, nationally and internationally. This paper draws upon evidence from public health and adverse impact studies across climate science, hydrology, agriculture, public health, and the social sciences. It presents a conceptual model to support decision-making by recognizing both the proximal and distal pathways from climate-induced environmental change to national health and wellbeing. The proximal and distal pathways associated with food security, migration and mobility illustrate the diverse climate change influences in different geographic locations over different timescales. We argue that greater realization and articulation of proximal and distal pathways should radically alter how climate change is addressed as a national and international public health challenge.