The Weekly Dose: Climate change is killing us
If global warming continues to accelerate at its present rate, India’s annual mean temperature will shoot up by anything between 2.5 to 5 °C, by the end of this century. These temperatures are killing us.
46.9 °C. A few days ago, this was the temperature recorded at Maharashtra’s Akola, making it the second-hottest city in the world at the time. On that day, 12 of the world’s 15 hottest cities were in India. As I write this in the relatively ‘cool’ climes of 32 °C Mumbai, a bead of sweat oozes out of my worried temple, trickles down my cheek, and drops onto my T-shirt.
In the last thirteen decades, the world has warmed by about 0.85 °C, and not cooled back down. Each of the last three decades has been successively warmer than any preceding decade since 1850. 18 of the last 19 years have been the hottest ever recorded. Should global warming continue to accelerate at its present rate, India’s annual mean temperature will shoot up by anything between 2.5 to 5 °C, by the end of this century. If any old prattler moans about how it’s getting hotter, you now know the numbers that authenticate their claims.
What you may not know – and what I didn’t either, until I started researching for this column – is that these temperatures are killing us. According to the World Health Organisation, between 2030 and 2050, climate change alone will claim 250,000 additional lives. Every year.
A majority of those who succumb will be children, senior citizens, workers engaged in manual labour, and communities with inadequate access to healthcare. People living on small islands, in mountainous and coastal regions, and in megacities, are most vulnerable. India – with its numerous inhabited islands, extensive mountain ranges, densely populated 7,500 km coastline, and five mega-cities – should be very, very worried.
While heatstroke is the most obvious heat-related cause of death – heatwaves in Odisha and Andhra Pradesh in 1998 and 2003 killed over 2,000 and over 1,400 Indians respectively – climate change is decimating us in many other ways.
In school, we learnt how the ozone layer – high up in the stratosphere – protects life on earth. However, when the same ozone is formed at the earth’s surface, it enters our lungs, interferes with oxygen transfer to our blood, and stresses out our hearts. Higher the temperature, more the sunlight, greater the concentration of greenhouse gas nitrous oxide, more is the ‘bad’ ozone formed. Hence, extremely high temperatures can trigger irregular heartbeats, heart attacks, strokes, and premature death in patients of heart disease.
These burning temperatures, which also dry the air of moisture and make it dustier, promote the entry of small particulate matter into our lungs and bloodstream, which goes on to wreak havoc in our bodies, resulting in increased emergency department visits and hospital admissions.
While we associate the exacerbation of lung diseases primarily with winter, soaring temperatures can be equally lethal. The aforementioned dust particles can irritate the airways, provoke coughing and difficulty in breathing, hamper lung function, and lead to chronic bronchitis. Globally, 300 million people are asthmatic; extreme heat ramps up the levels of pollen and other allergy-inducing stimuli in the air we breathe, triggering an attack.
Climate change interferes with the water cycle, unpredictably causing both drought and deluges. Drought favours the growth of a fungus which produces a toxin that is a known cause of liver cancer; those who consume nuts and corn infected with this fungus are at a higher risk of developing it. Drought also promotes crop-pest infestation; DDT is a commonly used pesticide in India, which, when it enters and remains in the bloodstream of pregnant women, causes their daughters to have shortened menstrual cycles and a lesser chance of conceiving, several years later.
In the last half-century, weather-related natural disasters have more than tripled; the frequency and intensity of floods are expected to increase this century. Rising temperatures melt glaciers faster, causing devastating flash floods. These deluges leach surface-level pollutants into the ground-water; worldwide, over 100 million people are thus exposed to arsenic, which impedes foetal development and causes spontaneous abortions. Mercury and lead become concentrated in seafood, which, when consumed by a pregnant woman, reduces the future IQ of her child.
A study conducted in rural Tamil Nadu found that heavy rainfall may bring germs accumulated during dry weather into contact with children through their drinking water; searing days followed by heavy rainfall were associated with a two-to-three times higher chance of contracting diarrhoea.
Irregular rainfall shrinks the pool of available potable water, leading desperate communities to draw on unsafe sources of water; in the next forty years, climate change alone will be responsible for up to a 21% increase in India’s diarrhoea cases. Sultry climes favour the blooming of harmful types of algae in freshwater sources, as well as ramp up the rates of food-borne germ-caused diseases. Rising sea surface temperatures can result in an increase in the species of bacteria which cause cholera.
Have you noticed that many recent epidemics – SARS, avian influenza, Zika, Nipah – originated from insects and animals? Since higher temperatures favour the survival of the mosquito that transmits malaria, changes in climate lengthen the window for its transmission. For example, this window will soon increase from 4-6 months to 7-9 months in a year in Madhya Pradesh. Global warming of 2-3°C is projected to increase the number of people at risk of malaria by up to 5 percent globally: 150 million people.
Indian scientists have proved that in hotter weather, the dengue virus needs lesser time to mature in mosquitoes, thus increasing its transmission rate. Extremes in climate create ideal ecological conditions for the multiplication of mosquitoes which spread chikungunya. Global warming allows the creatures that spread disease to enter new areas that were previously too cold for them, and reintroduces diseases at places where they had earlier been eradicated.
As I write this, a sixteen-year-old Swedish schoolgirl named Greta Thunberg is traveling across Europe (by train, to reduce her carbon footprint), urging governments to act in order to arrest climate change. In response, the United Nations Secretary-General wrote: “These schoolchildren have grasped something that seems to elude many of their elders: we are in a race for our lives, and we are losing.”