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CLIMATE
CHANGE AND HEALTH |
Suffering progress
Rising global temperatures will result in 290 million
more cases of malaria worldwide
About 2.5 million premature deaths will occur every
year in India due to air emissions
Asthma, diarrhoea, dengue, cancer, malnutrition will
burden public health
Climate change is bad news for global human
health. And fossil fuels are the greatest culprits. Studies have shown that the
atmospheric accumulation of gases stemming primarily from fossil fuel combustion could
increase the global surface temperature by 1.5-4°C. Global warming will expand the range
and incidence of vectorborne diseases, increase the incidence of pathogens in freshwater
and exacerbate heat-stress related mortality. This might be accompanied by the ill-effects
associated with ozone depletion, caused by emissions of chlorofluorocarbon (CFC) gases.
Effects would include increased skin cancers and cataracts, as well as possible impacts on
the human immune system that may weaken resistance to some infectious diseases.
Projections show that by the year
2100, the global average surface temperature will rise between 1.4°C to 5.8°C. The
twentieth century has been witness to unprecedented economic activity — an almost
twenty-fold rise over the previous decade — a major cause of climbing temperatures.
In addition, there has also been a dramatic increase in the world population that has now
exceeded the six billion mark. This is accompanied by a marked depletion in the
earth’s natural resources, radically changing the global environment.1 By
destroying forests, damming rivers, letting wetlands decay and disturbing climate
patterns, human actions are undermining ecological safety nets. Climate change results in
fluctuations in weather patterns, blurring of seasons, increase in sea-levels, melting of
glaciers and depletion in ozone level. Climate change also results in a fall in
agricultural productivity, increase in number of infectious diseases, instability in water
supply and the dying out of many species of plants, animals and birds. (see box: What is
climate change?).
What
is climate change? |
The short wave energy received
from the sun is absorbed by the atmosphere, ocean, ice, land and living organisms, whereas
the long wave radiation emitted by the warm surface of the earth gets partially absorbed
by trace gases in the atmosphere called greenhouse gases (GHGs). The main natural
greenhouse gases are water vapour (H2O), carbon dioxide (CO2) and methane (CH4). There is
usually a balance between the energy absorbed from solar radiation and the deflected
radiation from the earth and atmosphere. Increased levels of these GHGs in the atmosphere
are responsible for the increase in the global temperature. Since 1975, average world
temperature has increased by approximately 0.5°C and climate change could be due to
accumulation of GHGs in the lower atmosphere. This climate change encompasses temperature
changes on global, regional and local scales, and also changes in the rainfall, winds, and
possibly ocean currents.1 In India distinction between seasons has blurred. The monsoon
season has disappeared in Delhi. A mere two degree celsius rise in temperature along with
a seven per cent rise in rainfall would result in a cut down of 12 per cent of
agricultural revenues for India. States likeUttar Pradesh, Haryana and Punjab would record a 10 per cent
reduction in the production of wheat, thereby jeopardising food availability of the
country.2
References
1. Nathan Chan 1999, An integrated
assessment framework for climate change and infectious diseases, in
Environmental Health Perspectives, Vol 107, No 5, May, p 329.
2. Jagdeep Saxena 2002, Waiting for
devastation?, in Rashtriya Sahara, March. |
According to The World Health Report, 2002: Reducing
risks, promoting healthy life, climate change claimed 154,000 deaths through
diarrhoea, malaria and dengue fever in 2001.2 With production yields decreasing and
disruptions in food supply, undernourishment is going to increase. This could well
translate into more cases of stunted physical and intellectual growth in children, low
productivity in adults and their susceptibility to infectious diseases. Increase in carbon
dioxide emissions is also known to negatively affect the photosynthesis process in plants,
leading to an epidemic of malnutrition (see box: A malnourished world).
A
malnourished world |
| By 2100, plants will be exposed to
approximately 550 parts per million of CO2. Rising levels of CO2 makes plant barren and
denudes them of vital micronutrients such as iron, zinc, selenium and chromium. A raised
level of CO2 increases photosynthesis, which ruins the plant growth, stiffling the plants
capacity to absorb nutrients, hence making fewer amounts of nutrients available. Studies
on rice show a decline in nitrogen levels by 14 per cent, phosphorous 5 per cent, iron 17
per cent and zinc 17 per cent. Almost 84 per cent
of our calorie intake is provided directly by plants. Plants provide us with 32
nutritional elements, 24 of which are essential for the human body. Decline in
micronutrients like iron, leads to mental and physical impairment affecting almost 3.5
billion people — over half the world's population. Pregnancy complications resulting
in poor growth and health in childhood can be attributed to zinc deficiency in the diet of
the pregnant mother.
Sums up Irakli Loladze, biologist with the Princeton University,
New Jersey, USA, "To avoid malnutrition you have to consume more calories. To keep
the same calorie intake, you have to accept a diet low in essential elements. In either
case, not a healthy choice."1
Reference
1.
Irakli Loladze 2002, Rising atmospheric CO2 and human nutrition: toward globally
imbalanced plant stoichiometry, in Trends in Ecology and Evolution, Vol 17, pp
457-461. |
In 1990, out of the 21 billion tonnes of carbon emissions
globally, 14 billion tonnes were emitted by rich developed countries, with the US alone
contributing five billion tonnes.
 Power games
In 1992, 165 nations signed the United Nations Framework Convention on Climate Change
(UNFCCC) to combat climate change. The Kyoto Protocol was adopted under UNFCCC in 1997 and
it laid down a timetable for industrialised countries to reduce their greenhouse emissions
by at least 5.2 per cent compared to 1990 emissions levels by 2008-2012. The US agreed to
reduce emissions by seven per cent, Japan 6 per cent and European Union by 8 per cent
below 1997 levels. The Protocol also allowed any country committed to reducing emissions,
to gain credit points by setting up projects in developing countries that helped to reduce
the amount of greenhouse gases (GHGs) in the atmosphere. In 2001, the US refused to go
ahead with the Kyoto Protocol, citing reasons such as it "being unfair to the US
economy", "CO2 is not a pollutant", and "the science of global warming
is as yet unsure".3
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