How Will Climate Change Impact India And What Can Be Done?
With respect to climate change, mean annual temperature has increased, with an increase of 0.56 degree Celsius per 100 years between 1901 and 2007. Unusual and unprecedented spells of hot weather are expected to occur far more frequently and cover much larger areas. Under 4°C warming, the west coast and southern India are projected to shift to new, high-temperature climatic regimes with significant impacts on agriculture. With built-up urban areas rapidly becoming “heat-islands”, urban planners will need to adopt measures to counteract this effect.
A decline in monsoon rainfall since the 1950s has already been observed. The frequency of heavy rainfall events has also increased. A 2°C rise in the world’s average temperatures will make India’s summer monsoon highly unpredictable. At 4°C warming, an extremely wet monsoon that currently has a chance of occurring only once in 100 years is projected to occur every 10 years by the end of the century. An abrupt change in the monsoon could precipitate a major crisis, triggering more frequent droughts as well as greater flooding in large parts of India. India’s northwest coast to the south eastern coastal region could see higher than average rainfall. Dry years are expected to be drier and wet years wetter. Improvements in hydro-meteorological systems for weather forecasting and the installation of flood warning systems can help people move out of harm’s way before weather-related disaster strikes. Building codes will need to be enforced to ensure that homes and infrastructure are not at risk.
Evidence indicates that parts of South Asia have become drier since the 1970s with an increase in the number of droughts. Droughts have major consequences. In 1987 and 2002-2003, droughts affected more than half of India’s crop area and led to a huge fall in crop production. Droughts are expected to be more frequent in some areas, especially in north-western India, Jharkhand, Orissa and Chhattisgarh. Crop yields are expected to fall significantly because of extreme heat by the 2040s. Investments in R&D for the development of drought-resistant crops can help reduce some of the negative impacts.
More than 60% of India’s agriculture is rain-fed, making the country highly dependent on groundwater. Even without climate change, 15% of India’s groundwater resources are overexploited. Although it is difficult to predict future ground water levels, falling water tables can be expected to reduce further on account of increasing demand for water from a growing population, more affluent life styles, as well as from the services sector and industry. The efficient use of ground water resources will need to be incentivized.
Mumbai has the world’s largest population exposed to coastal flooding, with large parts of the city built on reclaimed land, below the high-tide mark. Rapid and unplanned urbanization further increases the risks of sea water intrusion. With India close to the equator, the sub-continent would see much higher rises in sea levels than higher latitudes. Sea-level rise and storm surges would lead to saltwater intrusion in the coastal areas, impacting agriculture, degrading groundwater quality, contaminating drinking water, and possibly causing a rise in diarrhoea cases and cholera outbreaks, as the cholera bacterium survives longer in saline water. Kolkata and Mumbai, both densely populated cities, are particularly vulnerable to the impacts of sea-level rise, tropical cyclones, and riverine flooding. Building codes will need to be strictly enforced and urban planning will need to prepare for climate-related disasters. Coastal embankments will need to be built where necessary and Coastal Regulation Zone codes enforced strictly.
Even without climate change, world food prices are expected to increase due to growing populations and rising incomes, as well as a greater demand for biofuels. While overall rice yields have increased, rising temperatures with lower rainfall at the end of the growing season have caused a significant loss in India’s rice production. Without climate change, average rice yields could have been almost 6% higher (75 million tons in absolute terms). Recent studies show that wheat yields peaked in India and Bangladesh around 2001 and have not increased since despite increasing fertilizer applications. Observations show that extremely high temperatures in northern India - above 34°C - have had a substantial negative effect on wheat yields, and rising temperatures can only aggravate the situation. Seasonal water scarcity, rising temperatures, and intrusion of sea water would threaten crop yields, jeopardizing the country’s food security.
Should current trends persist, substantial yield reductions in both rice and wheat can be expected in the near and medium term. Under 2°C warming by the 2050s, the country may need to import more than twice the amount of food-grain than would be required without climate change. Crop diversification, more efficient water use, and improved soil management practices, together with the development of drought-resistant crops can help reduce some of the negative impacts.
Climate change is expected to have major health impacts in India- increasing malnutrition and related health disorders such as child stunting - with the poor likely to be affected most severely. Child stunting is projected to increase by 35% by 2050 compared to a scenario without climate change. Malaria and other vector-borne diseases, along with and diarrheal infections which are a major cause of child mortality, are likely to spread into areas where colder temperatures had previously limited transmission. Heat waves are likely to result in a very substantial rise in mortality and death, and injuries from extreme weather events are likely to increase. Health systems will need to be strengthened in identified hotspots.
