Medical Sciences and climate breakdown: time to move beyond evidence to action

Medical Sciences and climate breakdown: time to move beyond evidence to action

Oxford's Medical Sciences Division is home to a number of groups investigating and tackling the climate crisis.

Over recent weeks and months, global actions on climate led by youth strikers, and the latest IPCC report on the Oceans and Cryosphere, in addition to those on land use and the IPCC Special Report on 1.5°C,  have highlighted the extent of climate crisis and the need for urgent action.

The effects of temperature increases are already being felt, with increasingly frequent and severe extreme weather events such as this year’s record heatwaves, droughts and forest fires. Warming beyond  1.5°C will result in considerably greater impact on human health, food security and water supply, and the biodiversity and ecosystems we co-exist with. These changes will disproportionately affect the most disadvantaged and vulnerable populations. The IPCC Special Report on 1.5°C highlighted the urgency of action needed, showing that a reasonable chance of limiting global warming to 1.5°C requires halving greenhouse gas emissions globally by around 2030 – a profound change needing 'rapid and far-reaching' system transitions.

Climate breakdown, and efforts to control it, will impact all aspects of our lives. The WHO called it the greatest challenge of the 21st century, saying it 'undermines the social and environmental determinants of health, including people’s access to clean air, safe drinking-water, sufficient food and secure shelter.' We are already witnessing health impacts, from extreme weather events causing public health emergencies, to increases in mortality caused by excessive summer heat and air pollution.

Universities have a significant role to play in efforts to understand and tackle the climate emergency. These efforts are by their nature interdisciplinary, exemplified through university initiatives such as the Rockefeller Foundation Economic Council on Planetary Health at the Oxford Martin School and the ONE network.

As a leading medical sciences research institution, the Medical Sciences Division is home to a number of groups investigating and tackling the climate crisis. Agriculture, forestry and land use contribute around 23% of global greenhouse gas emissions and this is strongly linked to our dietary choices. Public health researchers in the division have been investigating what dietary choices are most likely to lead to both sustainable and healthy outcomes; ten years ago the evidence was already sufficient for them to conclude that the most important driver for healthy, sustainable diets is to reduce meat and dairy consumption. The Nuffield Department of Population Health is home to the EPIC-Oxford prospective cohort, one of the largest investigations of the health impact of vegan and vegetarian diets in the world. Data from EPIC-Oxford participants were vital in establishing that the carbon footprint of self-selected vegan diets is half that of a meat-based diet. Since then, epidemiologists, behavioural scientists and public health modellers from across the division have united with physicists, geographers and political scientists in the multi-disciplinary LEAP (Livestock, Environment and People) project, which has published the latest evidence on the links between meat consumption and health outcomes, modelled the global health and environmental impact of moves towards sustainable diets, reviewed the evidence on nudging people towards plant-based diets, and contributed to the recent EAT-Lancet report on global healthy and sustainable diets. The LEAP project is holding a conference in Oxford to showcase the latest work on sustainable, healthy diets in December.

Changes in climate will alter the patterns of diseases that we research within the division. Changes in vector-borne diseases have already been noted, with global vectorial capacity for dengue the highest on record in 2016, increased environmental suitability for transmission of malaria, and worsening health outcomes in Lyme disease. Both the increased geographic range of these diseases, and climate-related displacement of human populations, will expose populations without innate resistance to diseases such as malaria and dengue, increasing disease severity in these regions.

We must also acknowledge that both healthcare and academia are significant contributors to greenhouse gas emissions. Many worry about the carbon footprint of our work. We need to start rethinking the way we communicate and cooperate as academics, and there are multiple steps we can take as researchers to mitigate our impact and show leadership on this issue.

Many of us work in complex international collaborations, with frequent flights for meetings and conferences the norm. Unfortunately, by 2050 – when global emissions must be net zero – aviation could have emitted one quarter of all the emissions we have left to 'spend' for a 1.5°C target, and still be emitting more than ever. Only a small fraction of the global population flies at all, and of these only a small fraction are frequent fliers, so the bulk of this large problem rests with a tiny minority. A massive scale up of 'sustainable' biofuels strongly challenges the growing needs to use land for food production and for increasingly threatened biodiversity, and so demand must be reduced.

Being particularly selective about long-distance conference attendance is a good first step. By choosing to fly less and communicating this, each person can influence many more. Changing attitudes towards travel as an indicator of career progression would be another (preliminary evidence suggests that air miles do not correlate with academic success), with the knock-on benefit of creating a level playing field for academics with significant caring commitments. Multiple-site conferences, with videoconferencing linking regional hubs, would allow networking but reduce total travel, permitting travel by train which has far lower emissions per passenger per mile. Ultimately, nearly carbon neutral conferences are possible, and may become a more common-place model. Changing these behaviours collectively as an academic community would overcome the 'first to act loses' attitude.

Our own researchers are producing convincing evidence of the impact of meat and dairy consumption on climate change (and other important environmental factors such as water use) and human health. We could support this with action in our own work environment, such as reducing meat and dairy options in workspace canteens and at catered events, following the lead of Goldsmiths and Cambridge.

Ultimately, however, there is a need to go beyond individual life-style changes and even our professional advancement of the science, and take action for bigger changes. As Greta Thunberg notes, 'What is the point of learning facts when the most important facts given by the finest scientists are ignored by our politicians?' As health researchers we are well placed to understand the evidence and implications; we must add our voices to those now calling for translation of evidence into action.