The hot weather in the summer of 2003 led to between 1,000 and 1,400 more deaths than normal in this period. The death rate was highest during the heat wave in August, but at the beginning of June and in the second half of July, too, more people died than usual in these months.
Estimated extra deaths
Highest mortality in August
The weekly death rate correlates with temperature levels, with an average delay of three days. An average increase in temperature of one degree results in 25 to 35 more deaths a week.
The hottest period was in the first half of August. In the fourteen days between 31 July and 13 August temperatures in De Bilt were higher than 25 degrees and on seven days even more than thirty degrees. Normally in August the temperature is just over 22 degrees. If this had been the case this year, four to five hundred fewer people would have died. For the whole of august, between 450 and 650 more people died than normal for this month.
Deaths per week, summer 2003
More deaths in June and July too
Temperatures of over 22 degrees were also often recorded in June and July. In June between 250 and 350 more people than usual died because of the heat. The beginning of June in particular was hot and in the first week there were 150 more deaths than normal for this period. Between 13 and 26 July the heat claimed three to four hundred extra lives.
Joop de Beer and Carel Harmsen