By Professor Anthony Seaton
A member of the congregation of St Mary's Cathedral
and Emeritus Professor at the University of Aberdeen's School of Medicine, Medical Sciences and Nutrition
YOU WON'T REMEMBER IT, but your first breath was a miracle of nature. Previously, your lungs contained only fluid and your nourishment and oxygen had come from your mother through the umbilical cord. The midwife slapped your back, you took a deep breath and yelled. At that moment, the blood that your heart was pumping was diverted by reflex closure of vascular by-passes, so half now passed through your lungs, allowing it to pick up oxygen and to remove the carbon dioxide your muscles were generating. The cord was cut and you were an independent being, all within a minute or so. Everyone around you breathed a sigh of relief as your mother enjoyed her first cuddle. You had placed your first individual carbon footprint on the world around you.
From that moment on, we take air for granted and only think of it when we exert ourselves or when the wind moves it around. We see its power in moving trees and we have used that power for millennia to sail, drive machinery, and raise water; now wind is the most important source of renewable power for electricity generation and one on which human survival will soon be dependent. I hope you use it to dry your washing as did your mothers and grandmothers. Air does more than ensure you are given oxygen; like the oceans and rivers, its power can be harnessed. However, there is a negative side.
The most obvious threat from air comes from storms, cause of countless deaths of seamen over the centuries Storms at sea pick up energy from the water, the higher its temperature the stronger the storm - they are increasing in force and in destructiveness world-wide. As with their temperature-related cousins, drought and inland flood, these storms are serious displacers of people and populations, part of the cause of the current migration issue that we cannot afford to ignore in planning for the future of our islands and continent.
Air is also a medium for transport, most obviously of aeroplanes, birds and insects but also of pollen, fungal spores, bacteria and viruses. Throughout your life you have been inhaling this assortment of things and you will have suffered common colds, sore throats and, possibly, covid or pneumonia. The air carried the causative organisms and insect vectors of many of the fatal childhood diseases before the middle of the 20th century. At that time, survival to adulthood was a lottery, influenced by individual immunity which in turn was influenced by nutritional status, so the children of the wealthier were better protected. And over the 20th century, vaccines were developed, the main cause of the striking increase in our life expectancy over the past 100 years. When I was born, the life expectancy of a British male was 65 – the Welfare State and vaccines have given me an extra 20 years.
Thinking of my early years brings me to what was then the most obviously unpleasant feature of air, pollution by coal smoke. This still occurs in poorer countries and kills many older people from heart and lung failure. We are fortunate in the UK and Europe generally that this has been reduced in our cities most of the time to trivial levels, and it is now difficult for researchers to find significant acute effects on our health. It has however left a serious legacy as one of the important contributors to risk of heart and vascular disease and probably dementia in the many of us who have lived through more polluted times. The problem of acute effects on lungs and heart has now largely been exported to less wealthy countries, but the main cause, burning fossil fuel in vehicles and houses, is still producing far too much of the colourless, odourless pollutant, carbon dioxide (CO2).
The concentration of CO2 in our air has driven the world’s temperature over the past 12 months to an average of 1.6⁰C above that of pre-industrial times. The 2⁰C limit is now likely to be exceeded within a few decades even if we reach carbon zero by 2040. The risks of today’s disasters – extreme heat waves, floods, migration of the dispossessed, conflict over land and resources, deaths of trees, plankton, and many other species (including Homo sapiens) will increase. Coastal cities will flood, southern Europe will become a fiery desert, and hoards will migrate north. Starvation, drowning, and death by wildfire and warfare are some of the fatal consequences of climate change; Sudan is a current example. I have watched and warned as this has moved north to Europe, but most people seem to be in denial.
Since I took my first breath, I estimate I have breathed out around 80 tonnes of carbon dioxide. To offset this out would have required about100 hardwood trees to have been planted and to have survived to my 80th birthday (a tree will absorb roughly 1 tonne CO2 over a century). But my total carbon footprint is far higher, as I have driven cars, heated my houses, eaten meat, bought unrecyclable goods, and flown in aeroplanes far more than I should have done. It is this extra use of energy by all of us individually in the wealthier world, producing 10-13 tonnes carbon per annum or on average 10 times more in UK than we produce by breathing, that has driven climate change and is thus our personal responsibility.
Not until 25 years ago did I realise this and resolve to cut my carbon footprint and urge others to try to do the same. As I approach my final breath, I feel the guilt of my previously careless lifestyle but hope that my readers will get the message. It is almost, but not quite, too late to prevent the worst - the collapse of the biosphere of which we are a part from climate chaos.
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