Intended for healthcare professionals


Climate change: the challenge for healthcare professionals

BMJ 2013; 347 doi: (Published 09 October 2013) Cite this as: BMJ 2013;347:f6060
  1. Anthony Costello, director,
  2. Hugh Montgomery, professor of intensive care,
  3. Nick Watts, research fellow
  1. 1Institute for Global Health, University College London WC1N 1EH, UK
  1. Anthony.costello{at}

They need to use their ability to communicate bad news in a way that stimulates a positive response

The key conclusions of the Intergovernmental Panel on Climate Change are profoundly worrying, not only for our environment but also for public health.1 Warming of the climate system is unequivocal, and, since the 1950s, many of the observed changes have been unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, the sea level has risen, and concentrations of greenhouse gases have increased relentlessly.

Despite the sceptic led publicity about the “pause” in surface temperature (using 1998, the warmest year on record, as an arbitrary baseline), each of the past three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850.2 (See appendix on for the panel’s detailed predictions.)

So why does global warming pose a problem to health? An increase in the frequency and severity of extreme weather events, worsening air quality, and changing patterns of vectorborne diseases will all have serious implications for global health. Extreme weather events (heatwaves, flooding, and droughts) will affect habitation and agricultural productivity, as will the rise in sea level. Mass migration may result, leaving those anchored in large cities by poverty or social disadvantage unable to escape the detrimental consequences.3 4 Conflict is probable.5

The biggest threat, however, may come from Donald Rumsfeld’s “unknown unknowns.” Biologists know that the most common cause of species collapse, or extinction, is coextinction. Small changes in average growing temperature, atmospheric carbon dioxide, ocean acidity, salinity, precipitation, and peak seasonal temperatures can have huge consequences for the life cycles and ecological balance of bacteria, fungi, plants, plankton, insects, amphibians, birds, and mammals—the ecological pyramid on which we rely.

Although the resilience of populations can rise with wealth, so too do the impacts of climate risks over time. The current trends and future projections from the intergovernmental panel’s report suggest that the risks from food insecurity, water insecurity, epidemics of emerging infections, and human conflict (as a result of competition for resources, population growth, and migration) present an absolute and unacceptably high risk to public health. Oxfam shares this view. In a new report, the organisation shows that climate change already threatens the production and distribution of food, reduces people’s ability to access food by undermining livelihoods and destabilising prices, and damages diets by putting at risk the quality of food produced.6

What can health professionals do? Climate change is a “superwicked” problem.7 It is time limited; difficult to define; without any “stopping rules;” the manifestation of many other problems; and “difficult or impossible to solve because of incomplete, contradictory, and changing requirements that are often difficult to recognise.7 We cannot assume that a future geek or Nobel prize winner will fix it. Nor have we faith that the body politic will be the driving force for climate stability when none wishes to lead. Finally, we cannot hope that unavailable and unproved solutions (such as geo-engineering on a global scale) will be safe or effective.

Health workers should consider five actions. Firstly, mitigation. Three to four degrees of warming presents an unacceptably high risk of catastrophe for public health. We cannot escape our responsibility to reduce carbon emissions any more than that for alleviating poverty or reducing tobacco use. Carbon taxes, renewable energy sources, and technological innovation are all part of the solution. Taxation should reward investment in new technologies and energy sources, and subsidies for fossil fuels should be reduced. There will be a price to pay, but the sooner we start, the lower the cost.8

Secondly, we need to shout from the rooftops that climate change is a health problem. The risks and hazards to public health are unacceptably high. Electorates worry more about health (their own and their children’s) than the survival of bears or bees. Doctors and nurses might be listened to more than environmentalists. The medical model has other benefits—when a patient is acutely sick, emergency doctors consider their options for the golden hour before seeking stability. For climate change, we are in our golden hour. Action can be delayed no longer.

Thirdly, climate change is about poverty and equity. We must speed up our attainment of sustainable development goals and protect the most vulnerable populations. Earthquakes of similar magnitude can kill tens of thousands in poor vulnerable populations but just a handful in wealthier countries, where resilience has been carefully planned. It will be the same for many effects of climate change. The poorest human populations rightfully need energy security for essential improvements in health and human development indicators, which will increase emissions in the short term. Consumption by the wealthy is the main problem for mitigation.

Fourthly, health professionals must advocate for political leadership and high level intergovernmental bodies to reduce the risk of climate change. At the same time, behavioural change for a sustainable lifestyle will depend on mass political movements—civil society, social media, and old fashioned community groups leading a transition to energy conservation and green prosperity.

Finally, we must advocate the mass scale-up of currently available solutions (insulation, recycling, conservation in energy and agriculture, solar power) in the health sector and beyond. We know what can be done but must evaluate how to do it at scale. Carbon capture and storage, green aviation, and renewable energy solutions need the massive capital investment they deserve. Energy companies need a vision of profits from carbon-free alternatives.

Climate change is a bad dream that won’t go away. As health professionals we have learnt to communicate bad news in a manner that stimulates a positive response rather than just anger, denial, or depression. The latest report shows that time is of the essence. Decisions made now will set the trajectory for climate instability and public health risks over the coming century.


Cite this as: BMJ 2013;347:f6060


  • Competing interests: We have read and understood the BMJ Group policy on declaration of interests and declare the following interests: None.

  • Provenance and peer review: Commissioned; not externally peer reviewed.


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