Flowers bloom earlier as United Kingdom warms
By Richard Black
Environment correspondent, BBC News British plants are flowering earlier now than at any time in the last 250 years, according to new analysis. Researchers stitched together nearly 400,000 first flowering records covering 405 species across the nation. Writing in the journal Proceedings B, they show that the average first flowering date has been earlier in the last 25 years than in any other period. Flowering dates are closely linked to temperatures recorded in the Central England Temperature Record. This is the longest continuous instrumental record of temperatures anywhere in the world, dating back to measurements made in 1659. During the 1980s and 1990s, the temperatures it registered rose by about 1C, although there is large variability from year to year. “There is a strong correlation between the flowering index and temperature, so what you see is in large part a reflection of the CET (Central England Temperature Record),” said Richard Smithers, UK conservation adviser at The Woodland Trust and one of the researchers on this project. “There have been other periods [in the record] when temperatures were warm, but the last 25 years is certainly the period when the index has been earliest,” he told BBC News. Across the plant record, researchers found that a temperature difference between two years of 1C equates to a difference in flowering time of about five days, with some species responding much more than others. …
