These were the key messages outlined in a highly significant report: ‘The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health’ – an international research collaboration partnered and funded by the Wellcome Trust.

Leading doctors, academics and policy professionals from 26 partner organisations have jointly authored the report, the findings of which, outlined in The Lancet medical journal, demonstrate the myriad ways climate change is already affecting the health of people across the planet.

The Countdown research, which builds on the work of the 2015 Lancet Commission on Health and Climate Change, shows the challenges are greater than anticipated, and that the impacts of climate change are disproportionately felt by communities least responsible for climate change and those who are the most vulnerable in society.

Five themes, 40 indicators
Unavoidable increases in global temperature and the role of climate change as a threat multiplier and an accelerant of instability, means many trends identified are expected to worsen significantly. Providing the first global stocktake of these issues, the report drills down into 40 indicators of trends across five working groups: climate change impacts, exposure and vulnerabilities; adaptation planning and resilience for health; health benefits; financial and economic factors; and public and political engagement.

A few of the existing health impacts documented include:

• An average 5.3-per-cent fall in productivity for rural labour estimated globally since 2000, as a result of rising temperatures. In 2016, this effectively took more than 920,000 people globally out of the workforce, with 418,000 of them in India alone.
• Between 2000 and 2016, the number of people exposed to heatwave events has increased by about 125 million, with a record 175 million people exposed to heatwaves in 2015. This supports the Lancet’s existing research showing just under 1 billion additional heatwaves exposure events occurring by 2050.
• Undernutrition is identified as the largest health impact of climate change in the 21st century. Related impacts of climate change on crop production referenced in the report include a 6-per-cent decline in global wheat yields and a 10-per-cent fall in rice yields for each additional 1^OC rise in global temperature.
• More than 803,000 premature and avoidable deaths occurred in 2015 as a result of air pollution across 21 Asian countries, attributable to just one type of air pollution from coal power, transport and use of fossil fuels in the home.
• The vectorial capacity for the transmission of Dengue due to climate trends has increased by 3 per cent and 5.9 per cent, respectively, since 1990 for just two types of mosquito. With 50 to 100 million infections of Dengue estimated to occur each year, this will worsen the spread of the world’s most rapidly expanding disease.

Accelerated response
Despite these and many other stark trends, the authors stress that the necessary response to climate change still provides an opportunity to realise substantial gains in public health. The potential benefits and opportunities are staggering, including: cleaning-up the air of polluted cities; delivering more nutritious diets; ensuring energy, food and water security; and alleviating poverty, alongside social and economic inequalities.

“Climate change is happening and it’s a health issue today for millions worldwide,” explains Prof Anthony Costello, co-chair of the Lancet Countdown and a director at the World Health Organisation. “The outlook is challenging, but we still have an opportunity to turn a looming medical emergency into the most significant advance for public health this century.

“As we move in the right direction, we hope for a step-change from governments to tackle the cause and impacts of climate change. We need urgent action to cut greenhouse gas emissions. The health and economic benefits on offer are huge. The cost of inaction will be counted in preventable loss of life, on a large scale.”

Notwithstanding the scale of the challenge, the report points to clear reasons for optimism. Momentum in cutting emissions responsible for climate change is building across a number of sectors, with significant benefit for public health to follow. This transition is most apparent in trends across the energy and transport sectors. Notable examples include peak global coal use, with numerous national commitments to phase-out coal power – across Canada, Finland, France, Netherlands and the UK – the rapid rise of renewable energy, and emerging transformation of transport driven by electric vehicles. These interventions are inextricably linked to improved air quality and substantial benefits for human health.

Christiana Figueres, chair of the Lancet Countdown’s High-Level Advisory Board and former executive secretary of the UN Framework Convention on Climate Change, says: “Most countries did not embrace these opportunities when they developed their climate plans for the Paris Agreement. We must do better. When a doctor tells us we need to take better care of our health, we pay attention, and it’s important that governments do the same.”

Other findings of the report show that over one billion people globally will be faced with a need to migrate within 90 years, owing to a rise in sea level caused by ice shelf collapse, unless necessary action is taken. Some 87 per cent of a random sample of global cities are in breach of WHO air pollution guidelines, putting billions of people at risk of unsafe levels of fine particulate matter (PM_2.5). Global exposure to PM_2.5 air pollution has increased by 11.2 per cent since 1990.

The world has also seen a 46-per-cent increase in weather-related disasters since 2000. This contributed to $129 US billion of economic losses caused by climate-related events in 2016 alone; in low-income countries, 99 per cent of losses are currently uninsured.

Professor Hugh Montgomery, co-chair of the Lancet Countdown and director of the Institute for Human Health and Performance, University College London, concludes: “We’re only just beginning to feel the impacts of climate change. Any small amount of resilience we may take for granted today will be stretched to breaking point sooner than we may imagine.

“We cannot simply adapt our way out of this but need to treat both the cause and the symptoms of climate change. There are many ways to do both, which make better use of overstretched healthcare budgets and improve lives in the process.”