Why it's important
Phenology, the science of recording natural regularly occurring events, already provides some of the longest written biological records in Britain.
If we continue to collect this valuable information on seasonal occurrences we will be able to demonstrate how climate change is affecting our wildlife habitats.
Evidence for climate change
The Woodland Trust believes that climate change is the biggest single threat to what little remains of our ancient woodland heritage.
The 20th century has seen a steady increase in temperature with the 1990s being the warmest on record. The mean temperature for January-March in the 1960s was 4.2°C compared to 5.6°C in the 1990s. The mean temperature in the spring of 1999 was 6.1°C. October 2001 was the warmest October on record with the average temperature for the month 3°C higher than usual. The global surface temperature for 2002 was the second highest on record, and 2002 in the UK was the fourth warmest year on record.
Phenology offers real evidence that climate change is happening now and that it is already having a significant effect on our wildlife. Trees are coming into leaf sooner, and some typical spring flowers are increasingly being seen coming into bloom in November and December.
View our live maps to see what is happening this season. Butterflies are appearing earlier and the red admiral butterfly, the chiffchaff and blackcap (two woodland birds) are increasingly over wintering in the UK.