Global warming is posing a risk to river shipping in northwest Europe as summers are expected to become drier, the Dutch meteorological institute KNMI said on Tuesday. KNMI's climate scenarios envisage that summers would become hotter and the number of rainy days in summer would decrease by 2050, while winters would be milder and wetter, Rob van Dorland of the KNMI atmospheric research department told Reuters.

Drier summers will lead to more frequent problems with low water levels on the rivers Rhine and Meuse as well as other inland canals, which are key transportation routes in north-western Europe. "This has large consequences not only for the Netherlands but the whole Rhine area," van Dorland said.

"Higher precipitation in winter means increased peak discharges for the rivers. In summer time it would be the opposite. Then we'll get problems for shipping and cooling water for energy plants," he added. Heatwaves in the past several years in the Netherlands temporarily restricted power plants' ability to use river water for cooling and forced them to trim output at a time when people turned up air conditioning and refrigerators.

The Netherlands and other European countries have seen unusually hot weather this summer and autumn, which lowered river water levels and made shipping operators impose cargo surcharges. Experts have said that the average global temperature in 2006 is likely to be among the five or six hottest since records began nearly 150 years ago. This year is on track to be the warmest in the Netherlands since temperatures were first measured in 1706.

Van Dorland urged the Netherlands, where rivers and canals are abundant, to alter its water management and start storing more water during the winter, which could later be used for irrigation and drinking during dry summers. Rising sea levels is another big concern in the Netherlands, where two-thirds of the land mass is below sea level.

The KNMI predicts that global warming is likely to raise sea levels along the Dutch coast between 0.35 to 0.85 metres by the end of the century, forcing construction of higher dykes. The KNMI forecasts that Dutch temperatures will rise by 0.9 to 2.3 degrees by 2050. It also expects the number of heatwaves and extreme downpours to increase in northern Europe.
(Planet Ark, 13/12/2006)
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