Met Office warns cities must adapt to cope with killer heat waves

Met Office warns number of nights yearly of dangerous temperatures to increase 5-fold

by Michael Smith (Veshengro)

New report predicts number of city heat wave warnings will increase five-fold within the next 30 years

The number of nights each year when temperatures in British cities reach dangerous levels will increase five-fold within the next 30 years, according to a new report from the Met Office. The report warns town planners and developers will have to adapt to cope with rising average temperatures.

This report, which is based on the latest computer models, predicts that the anticipated two degree increase in average temperatures over the next 30 to 50 years will include a significant increase in the frequency of heat waves.

These heat waves will be particularly badly felt in urban centers, where the so-called "heat island effect" ensures that cities retain heat during the night.

According to the Met Office, it expects to issue official heat wave warnings for urban centers four times more frequently than it does currently as the number of nights each year when temperatures stay above 20C rises from two to 10.

Hot nights are one of the main causes of fatalities during heat waves as elderly people and young children in particular struggle to recover from the heat of the day. During the 2003 heat wave between 20,000 and 35,000 excess deaths were believed to have resulted from heat exhaustion, including 2,000 people in the UK.

The report will further increase pressure on town planners and developers to better adapt cities to cope with higher summer temperatures, by providing more shade, green spaces and efficient cooling technologies. It will also strengthen the case for pilot projects that propose painting building's white to help them keep cool and reduce the "heat island" effect.

"A 2C rise in average temperatures may not sound very much but there would be a much bigger rise in extreme temperatures on the hottest days and nights," said Vicky Pope, head of climate advice at the Met Office. "We will need to adapt if we are to avoid the sort of serious impact we saw in 2003."

The problem is that the report is based on “computer models” and this is where we hit a snag for any computer modeling works on the “GIGO” principle, that is to say that you get out what you put in, aka “garbage in garbage out”.

We must, in my opinion, be very careful with computer modeling. In 2009 we saw how great computer models are for even shortish range forecast when we were told that we were going to have a “barbeque summer” which turned out to be more like a wet seasons than a BBQ summer.

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