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Endless sunshine: Spring 2020 was the sunniest on record, and one of the driest / KNMI: Driest spring ever measured




KNMI: Driest spring ever measured

The Netherlands experiences the driest spring on record. It is drier than in 2011, so far spring with the largest rainfall deficit. It fits in with a trend: the rainfall deficit in The Months of April and May has increased by almost 50% over the past 50 years.

Cor Bacon Cutter May 28, 2020, 9:00AM

Due to persistent drought, spraying is prohibited in some regions. No more spray water may be extracted from ditches, streams and canals.

This is reported by the KNMI in its weekly climate report. The precipitation deficit, a measure of drought, is the difference between the evaporation and the amount of precipitation. By the end of this week this will have risen to a record high in the Netherlands: 150 millimetres. Over the past half century, the rainfall deficit has increased by an average of almost 1 percent, or 0.57 millimeters, annually. This is mainly due to the increased evaporation. The amount of precipitation has hardly changed in the same period.

The increase in evaporation is due to rising temperatures, an increase in the number of hours of sunshine and a stronger solar radiation due to cleaner air and reduced cloud cover, says Peter Siegmund, climate researcher at the KNMI. Twice as much solar radiation gives twice as much evaporation. Per degree temperature increase, evaporation increases by 2 percent (in summer) to 3 percent (in winter).

Earlier this week, research by KNMI and Utrecht University showed that there are regional differences in the summer drought: it affects the interior harder and more frequently than the coastal regions of the Netherlands. On the coast, the amount of summer precipitation has increased in recent decades. These figures are for a different period of the year, Siegmund  explains. They are about precipitation deficits in the 'growth period' from April to September; the new drought figures relate only to the months of April and May.

Differences
Unlike in the spring, when the amount of precipitation has remained virtually the same in recent decades, the average amount of precipitation throughout the Netherlands continues to increase during the growing period. Like summer, spring has regional differences in rainfall deficits: evaporation and solar radiation, and therefore the deficiency of precipitation, are increasing more strongly inland than on the coast.

The Netherlands has had two dry and exceptionally warm summers. After a wet start to this year, not much rain has fallen since March. The effects of the drought are most evident in the East and South of the Netherlands, especially in agriculture and nature, reports the National Coordination Committee on Water Distribution (LCW). Due to the large rainfall deficit, groundwater levels there are on average very low for the time of year. It is not possible to supply river water to these areas. According to the weather forecast, the dry weather will persist for the time being.

According to the LCW, water management is in order and the drought has no impact on the drinking water supply. 'There are no bottlenecks in the sources (ground and surface water) for the preparation of drinking water', according to the LCW. The water supply through the Rhine and the Meuse is less than normal, but still sufficient for the drinking water supply. In the coming weeks, water supplies through these rivers are expected to decrease. In much of eastern and southern The Netherlands, bans or restrictions on the extraction of surface water.



Netherlands driest spring ever measured

Posted by Bart Verheggen on 28 May 2011

You might not say it after such a rainy day, but this spring is exceptionally dry in the Netherlands so far. The few rains that have fallen in recent weeks are  far from sufficient to fill the rainfall deficit (more evaporation than precipitation):

There was a lot of sun with high temperatures, which caused a lot of evaporation. Moreover, there has been little precipitation.

KNMI on the long-term trend and the current season:

The rainfall deficit in the Netherlands in the spring has been increasing in recent years. (...) The increasing trend is linked to an increase in evaporation, which in turn is the result of more sun and higher temperatures. (...) The increasing trend is not related to a decreasing trend in precipitation, the precipitation is increasing rather than decreasing in recent years. This spring, however, the amount of precipitation is very small. In addition, there is a lot of sun and the temperature is high, so there is a lot of evaporation. As a result, the rainfall deficit this spring is greater than ever.

The climate portal keeps a file on the drought in the Netherlands:

The Netherlands is facing the driest spring on record. The water levels in the Meuse and the Rhine are exceptionally low.

This has implications for agriculture and nature. By dewatering, peatlands emit additional greenhouse gases. The government is taking measures to minimise the negative effects of the drought.



Endless sunshine: Spring 2020 was the sunniest on record, and one of the driest
Society June 1, 2020
https://www.dutchnews.nl/news/2020/06/endless-sunshine-spring-2020-was-the-sunniest-on-record-and-one-of-the-driest/
The meteorological spring of 2020 will go down as the sunniest on record by far, with 790 hours of sunshine, compared with 517 in an average year. The new record also beats the previous one, set in 2011 by 47 hours, the KNMI weather bureau has confirmed. April was the sunniest April of all time and both March and May are in the top five. De Kooij, near Den Helder in Noord Holland had the most sunshine – 830 hours in total, while Twente had the least – 741 hours. Spring was also extremely dry, with just 77 millimetres of rain falling, compared with 172 in an average year. Most rain fell in March, and April and May are both among the driest on record. The lack of rain is also beginning to cause problems for water boards, and the situation has been made worse by the increase in demand because so many people are at home. This weekend drinking water company Vitens, which supplies 2.5 million homes in Overijssel, Gelderland, Friesland, Utrecht and Flevoland, lowered the pressure in its pipes to make sure it could guarantee supplies. Vitens is ‘urgently’ calling on customers not to water their gardens and to reduce the length of time they shower for, as well as to avoid using blow-up swimming pools.

Read more at DutchNews.nl:

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