Geoscience Reference
In-Depth Information
Human health
The potential health impacts of climate change are immense, and managing those impacts
will be an enormous challenge. Climate change will increase deaths from heat waves,
droughts, storms, and floods. However, higher global temperatures will also be a challenge
for many societies, particularly those that rely heavily on subsistence agriculture. As higher
air temperatures will make working outside more difficult and increase the likelihood of
hyperthermia. This will impact on the health of anyone who has to work outside regularly,
including construction and farm workers. Conversely, it has been suggested that the death
rate may drop in some countries: since many elderly people die from cold weather, warmer
winters would reduce this cause of death. However, this view has been contested as recent
research has shown that better housing, improved health care, higher incomes, and greater
awareness of the risks of cold have been responsible for the reduction of excess winter
deaths in the UK since 1950. Hence in many societies adaptation to cold climate and im-
proved protection for the most vulnerable members of society means that warmer winters
will have little or no effect in reducing the death rate.
The 2009 the University College London's
Lancet
report 'Managing the Health Effects of
Climate Change' identified two major areas that could affect the health of billions of
people: water and food. The most important threat to human health is lack of access to
fresh drinking water. At present there are still one billion people who do not have regular
access to clean, safe drinking water. Not only does the lack of water cause major health
problems from dehydration, but a large number of diseases and parasites are present in
dirty water. The rising worldwide human population, particularly those concentrated in urb-
an areas, is putting a great strain on water resources. The impacts of climate
change—including changes in temperature, precipitation, and sea levels—are expected to
have varying consequences for the availability of fresh water around the world. For ex-
ample, changes in river run-off will affect the yields of rivers and reservoirs, and thus the
recharging of groundwater supplies. An increase in the rate of evaporation will also affect
water supplies and contribute to the salination of irrigated agricultural lands. Rising sea
levels may result in saline intrusion in coastal aquifers. Currently, approximately 1.7 billion
people, one-quarter of the world's population, live in countries that are water-stressed. By
2030 it is predicted there will be a 30 per cent increase in the demand for fresh water due to
increasing access to safe drinking water, and the 50 per cent increase in demand for food
and energy, both of which require large quantities of water.
