Climate change is "the biggest global health threat of the 21st Century", according to a key research review published in a leading medical journal.
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University College London (UCL) climatologist Mark Maslin called it "the Stern report for medics," referring to the 2006 review that outlined the future impacts of the climate change situation in economic terms and advocated comprehensive, early-stage action to address it.
"The medical profession has to wake up if we're going to save billions of lives. This is why it's in the Lancet - it is the only way to do this is working with medics and other professionals to get that message across," Professor Maslin said.
"Being a climatologist and jumping up and down pulling my hair out and saying 'we're all going to die in a horrible way' does not work."
Managing the health effects of climate change is a Lancet Commission Report resulting from a collaboration between the Lancet and University College london.
The commission has laid out a five-part assessment of the global health threat, taking into account the social and political aspects of the task at hand.
"Apart from a small dedicated band of researchers, I think the health lobby has come late to this debate, but there's much that we can do to protect billions of people now and in the future," said lead author Professor Anthony Costello from the Institute for Global Health.
The framework consistently touches on several themes: adaptation to a warmer world is a key concern for healthcare infrastructure; and widespread, local knowledge of climate change effects on health is essential.
It also stresses the value of adding the healthcare lobby's weight to the call for decisive action from politicians and policymakers on climate and carbon mitigation issues.
Although disease vectors, such as salmonella, are affected by temperature changes and are likely to ravage some populations, the authors believe that the primary global threat is from people themselves.
Climate change will exacerbate the divide between rich and poor, hitting the poorest communities first and hardest.
Population growth, primarily in least developed regions, will combine with climatic effects to cause instability of food and water supplies. That in turn will drive mass migrations and create civil unrest, they say.
"The Indian government has nearly completed plans for seven-foot-high double-thickness razor wire and steel fence 4500 kilometres long along the entire border with Bangladesh and it's there to keep out the climate migrants," said Institute for Health and Human Performance professor Hugh Montgomery.
Despite its core call to arms, the report is not a purely negative assessment of the situation.
"We felt that our report should somehow try to create a framework for hope and for action because a lot of people have gone from denial into a sense of shock and helplessness about climate change," said Professor Costello.
The commission will, with the report as its guiding document, try to raise the alarm throughout the global healthcare community.
It will also hold a summit in two years to assess progress toward a more adaptable, informed global healthcare industry.
"We've got the set of priorities now," Lancet editor Richard Horton told BBC "What we have to do is take them to every climate change conference, write about them, gather evidence and work to the summit in two years' time - you really can use the science to change policy."
Ther report is available on the Lancet Website.