Earth-shastra

Climate change is the biggest environmental challenge. The Intergovernmental Panel on Climate Change (IPCC) had warned that "climate is changing and that these changes are in large part caused by human activities", which it said, "is largely irreversible". This was reflected at the Paris summit on climate change in December, 2015, where 195 countries decided to reduce carbon emissions, a major factor responsible for  climate change. The signatories set a goal of keeping the rise in atmospheric temperature to below 2°C from the pre-industrial era. Later, at Incheon (South Korea) meeting of the IPCC on October 6, 2018, the goal was further revised to below 1.5°C. This signifies the commitment to bring down greenhouse gases to about half of their 2010 levels by 2030 and to zero by 2050, against an earlier target of 2075.

While climate change predominantly affects the environment, it directly and indirectly impacts health. For example, flash floods following the rise in temperature and heat waves can lead to increased incidence of heat stroke. The melting of glaciers result in the formation of glacial lakes, which may burst to cause flash floods that could be detrimental to  people living in the Himalayan and sub-Himalayan region. The rising sea level is a matter of existential crisis to islands such as the Maldives, Kiribati and Bangkok, as well as coastal regions of Bangladesh and India. 

Indirectly, changes in physical and biological conditions and ecosystem create an environment conducive for transmission of diseases such as diarrhoeal and vector-borne diseases. The World Bank estimates that an additional 150 million people could be at risk from malaria if the temperature was allowed to increase beyond 2°C. At the same time, if global efforts can contain rise in temperature to less than 1.5°C, around 3.3 million cases of dengue could be prevented in Latin America and the Caribbean alone. 

The floods in Mumbai (2005) and Kerala (2018) were followed by outbreaks of leptospirosis or rat fever. Similarly, the rise in sea surface temperature has been shown to increase the proliferation of cholera bacilli. Intense heat can create drought conditions and crop failures that would compromise food security and lead to malnutrition. 

Air pollution associated with climate change is a major risk factor for an increase in asthma and respiratory problems, especially among children in urban areas. More than 153 million premature deaths occur due to air pollution. It  can be prevented by 2100 if the rise in temperature is restricted to less than 1.5°C. Unfortunately, people at risk are the poor, the elderly and children. They have, however, no active role in contributing to climate change. How to tackle the climate change issue? There is a global consensus on two main strategies - the first is mitigation or reducing the carbon emissions, and the second, adaptation that relates to enhancing the capacity to respond to and cope with health consequences resulting from climate change. 

Major sources of gas emissions include industries, the transport sector, agriculture and housing.  Therefore, risk mitigation involves reducing carbon emissions by closing down polluting factories or making them use greener technology, enacting legislation to curb vehicular emissions, preventing the burning of crop residues and garbage, switching from carbon-producing fossil fuel to renewable sources of energy, and planting trees or green spaces as carbon sink. 

While the government role is to enact environment-friendly legislation or formulate policies, citizens can contribute through lifestyle and dietary changes such as cutting down on the consumption of red meat, adopting solar power, increasing the use of public transport, using energy-efficient implements and walking to the neighbourhood market. 

India has committed to reduce its emission levels by 33-35 per cent (from the 2005 levels) by 2030. It has placed more emphasis on renewable energy sources such as solar, wind, hydropower and nuclear that would constitute 40 per cent of its energy mix by 2030. 

Readiness to tackle health issues due to climate change is also required. The health sector must take a lead in these efforts specifically by systematically strengthening its response capacity by establishing an integrated environmental and health surveillance and early warning system. With the ability to anticipate the impact of climate change, health system must be prepared for an effective and rapid response to health emergencies, including disasters. 

Disasters such as floods and untimely snowfall damage crops and disrupt livelihoods of people. Adequate compensation should be provided to such affected communities so that they can rebuild and rehabilitate their lives.

Climate change is indeed a major global challenge for the 21st century. Among the outstanding issues include the transfer of clean technology and the financing for the mitigation and adaptation efforts by developing countries like India. Inspite of the ambivalence demonstrated by developed nations, particularly the US, which is historically responsible for climate change, all countries must realise the gravity of the situation and its impact on public health. The recognition of health impacts by global leaders is the first step that would hopefully lead to concrete and well-coordinated actions at the ground level across the world. 

— The writers are former Directors of the World Health Organisation, Regional Office for South-East Asia, New Delhi