WHY DO FLOWERS COME OUT EARLIER THAN IN THE PAST?

This question is often raised as being evidence for global warming. There is clear evidence for it, but what is not clear is exactly why it is happening. This article looks at the issue in detail. In the comments several readers show links to articles on the urban heat island (UHI) effect as a possible cause, while others point to the fact that there has been a preponderance of milder winters in the UK in recent years (which are welcomed by most people). The article itself from the Royal Society shows on its graph that springs have been both warmer and cooler in the period studied, so there is no single trend.