As temperatures soar, scientists have been collecting data amid the ancient ruins that symbolise the birthplace of western culture. These data, combined with measurements from aircraft and satellites, promise to improve 'urban heat island' forecasts to make life in modern-day Athens easier during heat waves.
Heat waves strike with relative frequency in the summer months across southern Europe but the Greek capital of Athens is notorious for its sweltering conditions. The city is particularly prone to high temperatures because of its dense layout, narrow streets, limited green space and long-standing air pollution problem. While the average daytime temperature for July is 33.5C, statistics show that the number of days that exceed 38C appears to be increasing dramatically.
Periods of hot weather are always felt more acutely in cities, especially at night. This is down to a phenomenon called an urban heat island, where the temperature in the city can be up to 10C higher than the surrounding countryside. The built-up urban environment tends to act like a giant storage heater, soaking up the heat during the day and releasing it at night. Air pollution, traffic, lack of open space and low evaporation also contribute to the heat of the city. In addition, appliances such as refrigerators and air conditioners have to work harder as the temperature rises. In turn, this adds more heat to the environment causing the situation to worsen.
Increased daytime temperatures and reduced night-time cooling have a huge impact on human health and comfort. Urban heat islands are associated with above-average rates of mortality, especially amongst the elderly. This is sadly illustrated by the 10-day heat wave that engulfed Athens in 1987 and responsible for claiming 926 lives. During this extreme event, the mercury climbed to 48C the all-time highest temperature recorded for metropolitan Athens.
In order to improve our understanding of the comple
|Contact: Robert Meisner|
European Space Agency