In The UK, Spring Is The New Summer, According To The Woodland Trust - BBC

Two events in nature that usually herald the beginning of summer have started already, say researchers looking into reports from the public. The blossoming of hawthorn and return of migrating swifts - usually in May - have prompted the Woodland Trust to declare "spring is the new summer".

The trust has been analysing reports from members of the public taking part in the BBC Springwatch survey. It said it showed how climate change was affecting wildlife and seasons.

The return of the swift from warmer countries, usually expected in mid May, could mean summer has come early, said environment correspondent Sarah Mukherjee. Sightings of swifts have been reported across south-east England and Gloucestershire over the last few days.

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Dr Kate Lewthwaite of the Woodland Trust said: "Thanks to the exceptionally mild start to the year we are experiencing, this summer signal is arriving three weeks earlier than the 11 May average." Dr Lewthwaite added the timing of the seasons was changing, with the mild winter and warm spring contributing to warmer than average temperatures.

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http://news.bbc.co.uk/2/hi/uk_news/6566401.stm