By: John Gibbons

In early 1855, a cholera epidemic was sweeping through the Soho district of London, and the death toll was rising daily. A local doctor John Snow, observed that most of the cases of cholera seemed to be clustered in the vicinity of one public water pump in Broad Street.

He persuaded the local authority to remove the pump’s handle – and the epidemic was contained. This was a defining moment in public health, and to this day, the removal of the Broad Street pump handle is revered as the founding event in the science of epidemiology, which is the study of diseases, how they originate and how they spread.

Though may be hard to believe it in Ireland today, up until relatively recently, cities were dangerous places to live. Up until the late 19th century, death rates were so high in cities that the only way their populations didn’t collapse was the constant influx of people from the countryside.

Today, one in two of people live in cities, and by 2030, that figure is expected to rise to 60%. Each of these cities is in itself a human ecosystem, and a fragile one at that, depending totally on a wide range of critical services, from safe drinking water, effective control of sewage and refuse to a reliable supply of food and fuel.

Cities themselves, of course, are virtually 100% dependent on ‘importing’ these vital supplies from elsewhere. And if these services fail for any length of time, the consequences for the totally dependent urban populations are dire. Witness the chaos and disruption created by even very short-term power cuts.

In Ireland, our vulnerability is even more so as an island nation. We depend on huge amounts of goods being delivered to our ports by ship (air freight accounts for only a tiny amount of total imports). We are also heavily dependant on imported energy in the form of oil, and worryingly, we are right at the end of long and complex supply chains for these vital supplies…

A major new report published in early 2008 by the UK’s Faculty of Public Health, warns that much of the progress made in public health in the last century is now in jeopardy. The culprit? Climate chaos, which now threatens “the basic elements of our existence – access to water, food production and land use – with huge implications for health and wellbeing”.

This firmly places climate change as the most severe health challenge in the decades ahead, outstripping any of the 20th Century’s great health bogies, such as cancers and heart disease.

“We’re facing a global health catastrophe”, according to Professor Alan Maryon-Davis, president of the Faculty of Public Health. “It’s up to all of us to use our collective knowledge and skills to lead the change to a healthy, sustainable future”. Strong words indeed.

And despite the impression given by the Irish government’s current advertising campaign, just one or two little changes will not set us on the road to a sustainable future. What is required is “nothing less than a total cultural change”, in the words of Sir David King, who served as Tony Blair’s Chief Scientific Advisor.

This sounds like a daunting, even frightening prospect, and it is. Yet, the Faculty points out that joined-up thinking can make dramatic differences that actually result in positive health benefits. For example, we all use our cars too much. If we reduce this usage (by walking, cycling and using public transport when possible) we get an immediate health gain in reductions in obesity, heart disease etc.

In turn, reduced car use means safer roads and public spaces. This eases the health burden of road accidents, and also encourages more people to cycle and walk, as they and their children feel safer on quieter roads.

Seeing your neighbours and their children out walking or cycling has a positive effect on people’s behaviour and helps motivate others. Best of all, these actions cause CO2 emissions to decline, so both personal health and the wider environment benefit.

In its landmark Fourth Report, published in 2007, the Intergovernmental Panel on Climate Change (IPCC) warned that climate change is “likely to affect the health status of millions of people across the globe”. Risks include:

1. Increased rate of heat-related deaths, especially among older, ill, very young and socially isolated people
2. Food and water (especially safe water) shortages
3. Malnutrition
4. Water-borne and food-borne diseases
5. Deaths, injuries and homelessness from flooding and other severe weather events

Looking at the list above, you may recognise that many of these effects are already in evidence in areas such as sub-Saharan Africa. It would, however, be a big mistake to think these are only other people’s problems.

In 2003, a severe heatwave in mainland Europe caused at least 30,000 premature deaths, with 11,500 in France – a highly developed First World country – alone, see graphic below. Heatwaves with temperatures of 35–40 degrees C are forecast to become almost commonplace in the next two decades.

By mid-century, these may well be the new ‘normal’ in central Europe, with huge health consequences for our European neighbours, many of whom are likely to have to flee northwards to escape the severe weather, droughts and constant fires.

This massive movement of homeless migrants will in turn place even greater strain on the health systems of countries such as Ireland, which are likely to be still habitable.

This may sound like science fiction, but it is in fact widely accepted among the scientific community, which has been tracking the relentless rise in temperatures worldwide for decades. Looking forward just 22 years – to 2030 – assuming CO2 concentrations in the atmosphere remain as high as they are today, global average temperatures will have risen two degrees C above their pre-industrial levels.

Two degrees doesn’t sound like much, but on a global scale it will take us to “the point beyond which catastrophic – and in some cases irreversible – impacts are likely”. This, remember, is not a warning issued by Friends of the Earth, but the august UK Faculty of Public Health. Ireland’s Institute of Public Health (IPH) also identifies climate change as a huge threat. It recently produced a booklet entitled ‘Sustaining a healthy future – taking action on climate change’.

IPH chief, Dr Jane Wilde says: As in many other areas of public health the impact will be felt most greatly by people in vulnerable groups. Our main focus must be to ensure that improving equity in health is at the forefront of our action. We want to support other colleagues in the UK and internationally to tackle one of the most significant issues in public health.'

Meanwhile, a major study, published last month in the British Medical Journal, pointed out that between 20–70 million more people will be living in malarial regions by 2080. “The health risks are massive, and the best way to mitigate them is to minimise the extent of climate change”, said the researchers. “Global community health is the climate change issue”.

While much of the focus has been on the possible economic impacts of climate change, in fact its consequences on human health far outweigh the economic costs. Put simply, our health depends on the planet’s health, and what threatens it, threatens us.

Were he alive today, it’s easy to imagine Dr Snow would now be a leading voice in the battle against pumping more and more carbon into our already highly stressed environment.

John Gibbons is Publisher of Climatechange.ie