Loud and clear

The World Environment Day is observed every year on June 5. The COVID-19 Pandemic has made us think that the issue of environmental degradation and climate change cannot be just a ritual discussion but one that has to be taken very seriously.

Climate change is a significant change in temperature, wind patterns and precipitation that may occur in cycles over decades, hundreds, thousands and millions of years; sometimes these changes may be random occurrences. These may result in extreme weather events like thunderstorms, cyclones, tornados, etc. In recent years, we have witnessed the impact of climate change occurring much faster and in a much shorter period.

In the last century, scientists detected that the temperature of the earth was rising abnormally. It was found that oceans were warming up and snow was melting leading to rising sea-levels. It was also found that there was a perceptible rise in the carbon dioxide concentration in the atmosphere.

Greenhouse Gases (GHGs) resulting from mainly industrial development and urbanisation, agriculture and changes in land-use patterns are the cause of global warming. Different gases have different Global Warming Potential (GWP) which denotes how much damage they cause to the

environment. Carbon dioxide (CO2) has a GWP of 1; Methane has a GWP

of 21 and Nitrous oxide has a GWP of 310.

The effects have been felt in India as well. There was an all India drought in 2002. There was an all India severe drought in 2009. The year 2010 was one of the warmest years. In the year 2013, there were extreme rainfall events in Uttarakhand. We have seen mountains areas becoming barren due to large scale cutting of trees. This is resulting in hills becoming more fragile as ecosystems. Tsunami and Amphan and now Nisarga are knocking on our western coast.

Climate and weather have always had a powerful impact on human health and well-being. Global climate change is a newer challenge to ongoing efforts to protect human health. In the past few years, there has been increased mosquito breeding, malaria, dengue and yellow fever. Increase in temperature by 2-3º C would increase the number of people who, in climatic terms, are at risk of malaria by around 3-5 per cent, which would equate to several hundred million people globally. According to the World Health Report 2002, climate change was estimated to be responsible in 2000 for approximately 2.4 per cent of worldwide diarrhoea, and 6 per cent of malaria in some middle-income countries.

In this century, we have witnessed the outbreak of SARS, H1N1 Flu, Swine Flu and now COVID-19. Several hypotheses are attributed to such outbreaks. The changing climate as

a result of human activity has caused several changes in the flora and fauna. Viruses are known to mutate and climate change is hastening the process.

Changes in atmosphere coupled with vehicular and industrial emissions lead to smog and poisonous gases which cause difficulty for those with cardiovascular disease, respiratory disorders as asthma, emphysema, chronic bronchitis and allergy problems.

Similarly, water pollution-related diseases are on the rise. Water and more importantly, drinking water is of poor quality because water resources are threatened by drought, leading to bacterial, viral, protozoal and parasitic diseases.

Climate change has several indirect effects on our health. As a result of rising sea levels and flooding of the coastal areas, there is an increase in population density in certain areas due to migration of people to safe areas. People have to live in makeshift camps in poor, unhygienic living conditions which cause several infectious diseases. Children lose access to education. There may be an upswing in incidences of violence for want of food and other basic amenities.

Human-induced depletion of stratospheric ozone is another issue affecting human health. Stratospheric ozone absorbs much of the incoming solar ultraviolet radiation (UVR), especially the biologically more damaging, shorter-wavelength, UVR. The solar ultraviolet radiation may cause diseases of the skin like malignant melanoma, non-melanocytic skin cancer, etc. They may affect our eyes in the form of

acute photokeratitis and photo conjunctivitis, Climatic droplet keratopathy, pterygium, cancer of the cornea and conjunctiva, cataract, uveal melanoma, acute solar retinopathy and macular degeneration. There is also an observable negative impact on immunity in the form of suppression of cell-mediated immunity, increased susceptibility to infection and impairment of prophylactic immunisation and activation of latent virus infection.

Climate change also leads to altered general well-being, disturbed sleep/wake cycles, seasonal affective disorder and disturbance in mood.

The health effects of climate change also depend on other relevant factors like age and gender, socio-economic condition, geographic locations, population density, sanitation and healthcare, nutrition, preexisting diseases, public healthcare system, literacy and infrastructure. People who are socially, economically, culturally, politically, institutionally, or otherwise marginalised are especially vulnerable to climate change.

There is an urgent need to take steps to prevent climate change to safeguard health. These may include policy-making and strategies to reduce the risks of climate change. There is a need to develop better infrastructure to combat the negative effect of climate change. A holistic approach is needed for the healthcare structure in the form of better nutrition, job opportunities, housing, shelter, clean water, etc.

"We have the means to limit climate change," said R. K. Pachauri – Former Chair of the IPCC. "The solutions are many and allow for continued economic and human development. All we need is the will to change, which we trust will be motivated by knowledge and an understanding of the science of climate change."

Views expressed are personal