Health, Climate and Environment
The world's climate system is an integral part of the complex life-supporting processes. Climate and weather have always had a powerful impact on human health and well-being. And like other large natural systems, the global climate system is coming under pressure from human activities. Global climate change is a more recent challenge to ongoing efforts to protect human health. For example, climate change has critical health implications. Changes in rainfall will affect the presence and absence of vector- and water-borne pathogens (IPCC 2001).
Extreme climate events such as tropical cyclones, droughts, severe floods and abnormal monsoons may lead to adverse implications on the health sector and the safety of life and property. For example, food supplies are destroyed, resulting in malnutrition, and water supplies deteriorate. Secondary effects include an increased risk of infectious diseases due to a breakdown in sanitation, lack of clean freshwater, as well as damage to local health care infrastructure.
Vector and water borne diseases are influenced by climate, as are some physiological conditions. For instance, following the heavy rainfall caused by the 1997/1998 El Niño in north-eastern Kenya and southern Somalia, the associated outbreak of Rift Valley Fever, which had earlier been effectively eradicated, killed large numbers of cattle, and even spread to humans.
Severe weather can take many forms, which vary widely in terms of both time and space. Local events such as tornadoes and thunderstorms cause sudden threats to a relatively small number of people, while persisting phenomena such as flood-producing rain or drought occur on a much wider scale. In both the short-term severe weather events and the longer-term slow onset phenomena, the human distress caused by the spreading of disease and food scarcity are often much worse than the initial direct damage. Sometimes persistent climate-related events even lead to sustained problems of famine and mass emigration. While weather phenomena themselves cannot be prevented from happening, much can be done to mitigate their impacts and prevent them from becoming major disasters.