Heatwaves and Droughts Facts

Heatwaves and droughts kill more people than floods, hurricanes and tornados combined, force the birth rate down and the murder rate up, and studies have shown that more boys are likely to be conceived during a heatwave. Heat waves are a force to be reckoned with.



  • A heat wave is defined as a phenomenon resulting from certain combinations of temperature, humidity, air movement and duration, with the potential to adversely affect communities. Simply stated, they are major killers.
  • There are three main definitions of drought: meteorological: a prolonged period with less than average rainfall; agricultural: when there is insufficient moisture for successful crop production; and hydrological: when available water reserves fall below the average due to increased consumption.
  • The highest recorded world temperature was 136 degrees Fahrenheit in Al Aliziyah, Libya, on 13 September 1922.

Around the World

  • In twentieth century Australia, heat waves caused more deaths than any other natural hazard after disease and illness. Heat waves, it has been estimated, kill more people than floods, tornadoes and hurricanes combined.
  • The 2003 August heatwave killed over 14,000 (mostly) elderly people in France and 2,000 in England and Wales.
  • The US summer of 1995 was so hot that by the end of August, methane started to emit within bales of freshly cut hay causing them to spontaneously combust.
  • In 1936 25 million people starved to death in the Sichuan Province of China. The African Horn faces an almost continuous battle with drought and famine.
  • The 1991 - 1992 Subsaharan drought covered 6.7 million square miles and affected 110 million people.

Quick Facts

  • Over 75 per cent of British workers say a heat wave hampers their ability to work effectively and more than half admitted to taking "sun-bathing days".
  • Studies have also shown that more boys than girls are likely to be conceived during a heat wave.
  • A 1988 New York heat wave saw the murder rate increase by 75 per cent.
  • Philadelphia, Pennsylvania, is one of many US cities that operate a "buddy system" during a heat wave. A designated person in each street checks on elderly and vulnerable people.
  • Following the British drought of 1976, the birth rate dropped to a record low, proving that the advice of the most popular car sticker of the year was not being followed: "Save Water, Take a Bath with a Friend".
  • A 1986 US study also showed reports of Domestic Violence peaked at the same time each year as maximum temperatures in five locations around the nation.
  • In 1842 a Belgian mathematician concluded "Crimes against property reach a maximum in winter months, and crimes against the person and against morals, in the summer months."