The picture that is emerging as Tim compares the records gives cause for concern.
Chris Packham: For centuries, people all over Britain have recorded the arrival of Spring. To chat about this desire to make natural notes and lists, and to explain what it reveals about the global climate, I’ve met up with wildlife recording expert Tim Sparks at my New Forest home.
Tim, look at this. This is just around the back of the barn here. These bees were here last year and I noticed them for the first time yesterday. So this is the sort of thing that’s going to make my diary, but why do you think people are so preoccupied by recording these sorts of signs?
Tim Sparks: Well, I think people are just desperate for the end of winter. And we saw that particularly this year because it was such a hard winter. People are so fed up with snow and cold they’re really keen to start recording these events. So, whether it be the first activity of bees or whether it be the first flowers in their lawn, whatever it might be, they’re desperate to see those and they’re very keen to record those in their diaries.
Chris: Tim has become one of Britain’s leading experts on the study of these seasonal events. It’s a science known as phenology. He believes phenology could give us vital clues about one of the biggest problems facing nature today, climate change. He’s gone back and found a vast array of records like this 17th Century book to try and piece together all of the evidence and see what it actually reveals.
Tim, have you been able to pull together all of this data over a period of years from a succession of sources to sort of produce any comprehensive picture?
Tim: Yes, we have. I mean, what we’ve done is, we’ve gone back to about 1750 in the UK. We’ve taken every scrap of flowering phenology data that we can find. We’ve combined all of this into the single series of the flowering dates of plants in the UK.
Chris: And what’s the story?
Tim: Well, the story is, they’re now earlier in the last 25 years than at any other point during that 250 year record.
Chris: The last 25 earlier than the previous 250?
Chris: So there’s no doubt in your mind at all then that we’re seeing effects of climate change with earlier springs?
Tim: No, none at all, and these flowering events are very strongly tied to temperature. So, for every one degree that it’s warmer, they’re flowering approximately five days earlier.
Chris: It’s a crucial piece of evidence and it helps us understand how climate change is affecting our natural world. And what’s amazing Is, it wouldn’t have been discovered without the likes of you and me having that passion to record the natural world around us.