On Saturday, King Willem-Alexander celebrates his 58th birthday. How has the climate changed during his life? And what will it look like when he turns 70 in 2037? And when Crown Princess Amalia turns 70?
58 Times the Weather on April 27
On the birthday of Willem-Alexander on April 27, 1967, the weather was dry and sunny, with a maximum temperature of 15 °C in De Bilt (image 1). Over the years, Willem-Alexander has experienced strongly varying temperatures on his birthday. The warmest was on his 40th birthday in 2007, when it reached no less than 27.3 °C. His 18th birthday in 1985 was the coldest, with a temperature of only 7.4 °C. Often needing a coat, but also years when the coat could stay in the closet.
And the Climate?
The climate is actually nothing more than the average weather. The weather is fickle and varies greatly from day to day and from year to year, hence the large differences you see on the Kings birthday.
Due to the unpredictability of the weather on individual days, it is difficult to say anything about a change in climate on a specific day. There are simply too few measurements and the variability is too great. For the same reason, we never look at daily records.
When you compare the first 29 birthdays of Alexander with the last 29, you do see some changes (image 1). The average maximum temperature on his birthday in the first half of his life was 13.5 °C, in the second half 16.2 °C. On average, it is a lot warmer. And on his 26th birthday, the temperature first exceeded 20 °C, which has now happened five times.
But to see more precisely how the climate has changed during the Kings life, it is better to look at the average temperature for the entire month of April or for the whole year.